Art
[1]
The present invention relates to a video signal processing method and apparatus.
BACKGROUND
[2]
Recently, the demand for high-resolution, high-quality video, such as HD (High Definition) video and UHD (Ultra High Definition) video is increasing in various application areas. Since the image data has been increasing the amount of high resolution, high quality is the more relatively data compared to traditional image data if the stored transmit image data using a medium such as an existing wired or wireless broadband, or with a conventional storage medium, transmission cost and It increases storage costs. In order to address these issues as the picture data of high resolution, high quality image can be compressed with high efficiency techniques are utilized.
[3]
A video compression techniques inter picture predicting the pixel values ​​of the current picture from a previous or subsequent picture in the current picture prediction techniques, by using the pixel information in the current picture screen for predicting the pixel values ​​of current picture prediction techniques, It may assign a short code to a value of high appearance frequency, and transmitted or stored until there is a variety of techniques, such as an entropy encoding technique for assigning a long code to the low frequency of appearance values, and effectively compressing the image data by using such a video compression technology.
[4]
On the other hand, with the increased demand for high-definition video, and even with increased demand for stereoscopic content as a new video service. There is ongoing debate about the resolution and second video compression technology to provide a high-resolution stereoscopic content effectively.
Detailed Description of the Invention
SUMMARY
[5]
An object of the present invention is to provide a method and apparatus capable of efficiently performing intra-prediction for a method as coding / decoding a video signal, an encoding / decoding block.
[6]
An object of the present invention is to provide a method and apparatus for performing intra-prediction by the weighted prediction using the plurality of reference samples, as in encoding / decoding a video signal.
[7]
SUMMARY OF THE INVENTION In the present invention are not limited to the technical problem mentioned above, it is not mentioned another technical problem will be clearly understood to those of ordinary skill in the art from the following description It will be.
Problem solving means
[8]
A video signal decoding method and apparatus according to the present invention, to determine the intra-prediction mode of the current block, based on the intra-prediction mode, and determines the first reference samples of the prediction samples contained in the current block, wherein 1 by using a reference sample, generating a first prediction samples for the prediction sample, the first prediction sample and using the second reference samples of different positions and wherein the first reference sample, for the prediction sample it is possible to generate a second prediction samples.
[9]
Video signal coding method and apparatus according to the present invention, to determine the intra-prediction mode of the current block, based on the intra-prediction mode, and determines the first reference samples of the prediction samples contained in the current block, wherein 1 by using a reference sample, generating a first prediction samples for the prediction sample, the first prediction sample and using the second reference samples of different positions and wherein the first reference sample, for the prediction sample it is possible to generate a second prediction samples.
[10]
In the video signal encoding / decoding method and apparatus according to the present invention, the second reference sample is at least one of the prediction reference placed on the same vertical line with the reference samples or the prediction sample is placed in the same horizontal plane with the destination sample Sample It may contain.
[11]
In the video signal encoding / decoding method and apparatus according to the present invention, the first reference sample and reference and the second sample may be adjacent to, each different boundary of the current block.
[12]
In the video signal encoding / decoding method and apparatus according to the present invention, the position of the second reference sample, can be determined based on the direction of the intra-prediction mode.
[13]
In the video signal encoding / decoding method and apparatus according to the present invention, the second prediction samples, the first sample and the prediction may be generated based on the weighted sum of the second reference samples.
[14]
In the video signal encoding / decoding method and apparatus according to the present invention, the first prediction sample and the second reference weight applied to the samples, respectively, the location and the second location, the first reference samples of the prediction samples of the position of the reference sample it can be determined based on at least one.
[15]
Whether or not in the video signal encoding / decoding method and apparatus according to the present invention, which to generate the second prediction sample, it can be determined according to the direction of the intra-prediction mode.
[16]
The for the invention briefly summarized above features are merely exemplary of yangsangil detailed description of the invention which will be described later, and are not intended to limit the scope of the invention.
Effects of the Invention
[17]
According to the present invention, efficient intra prediction can be performed for encoding / decoding the current block.
[18]
According to the invention, it may perform intra prediction on the basis of the weighted prediction using the plurality of reference samples.
[19]
Effects that can be obtained in the present invention is not limited to the effects mentioned above, are not mentioned other effects can be clearly understood to those of ordinary skill in the art from the following description will be.
Brief Description of the Drawings
[20]
Figure 1 is a block diagram showing an image encoding apparatus according to an embodiment of the present invention.
[21]
Figure 2 is a block diagram showing an image decoding apparatus according to an embodiment of the present invention.
[22]
Figure 3 illustrates an example of dividing the one embodiment to which the present invention is applied, coded block on the basis of the tree structure (tree structure) in a hierarchical manner.
[23]
Figure 4 is a view of the partition form of the invention is in one embodiment, the partitioning of the binary tree-based allowed to be applied.
[24]
Figure 5 is a view showing one embodiment to which the present invention is applied, for example, only a particular form of binary tree-based partition allowed.
[25]
Figure 6 is one embodiment to which the present invention is applied, a view for explaining an example in which the information relating to the division number allows a binary tree to be encoded / decoded.
[26]
7 is a view according to an embodiment to which the present invention is applied, illustrating a partition mode that can be applied to the coded block.
[27]
8 is a group according to an embodiment to which the present invention is applied, a video coder / decoder groups - shows a kind of definition of an intra-prediction mode.
[28]
Figure 9 is one embodiment to which the present invention is applied, showing the type of the extended intra-prediction mode.
[29]
Figure 10 is one embodiment to which the present invention is applied, a flow chart schematically showing the intra-prediction method.
[30]
Figure 11 is one embodiment to which the present invention is applied, on the basis of difference information of the neighboring sample illustrates a method for correcting the predicted samples for the current block.
[31]
Also as an embodiment 12 and 13 to which the present invention is applied, showing the method of correcting the prediction samples based on a predetermined correction filter.
[32]
Figure 14 is one embodiment to which the present invention is applied, showing the range of the reference samples for the intra prediction.
[33]
15 to 17 as an embodiment to which the present invention is applied, showing an example of a reference sample to filter.
[34]
Figure 18 is a using a plurality of reference samples, in accordance with one embodiment of the present invention, the view showing an example of inducing the right side reference sample or reference samples lower.
[35]
19 and 20 is a diagram illustrating determining the right side reference sample and the reference sample for the lower side, a non-square block in accordance with one embodiment of the present invention.
[36]
21 and 22 are diagrams showing the reference samples are rearranged dimensional reference sample group in a line.
[37]
23 is a view for explaining the distance between the first reference sample and the prediction sample.
[38]
24 and 25 are a view showing the positions of the first reference sample and the second reference samples.
[39]
26 is a view showing the positions of the first reference sample and the second reference samples.
[40]
27 is a flowchart illustrating a process for obtaining a residual sample in one embodiment where the present invention is applied.
Mode for the Invention
[41]
The invention will be described in bars, illustrated in the drawings certain embodiments that may have a variety of embodiments can be applied to various changes and detail in the Detailed Description. This, however, is by no means to restrict the invention to the specific embodiments, it is to be understood as embracing all included in the spirit and scope of the present invention changes, equivalents and substitutes. In describing the drawings was used for a similar reference numerals to like elements.
[42]
First, the term of the second, etc., can be used in describing various elements, but the above elements shall not be restricted to the above terms. These terms are only used to distinguish one element from the other. For example, without departing from the scope of the present invention, the first component may be referred to as a second configuration can be named as an element, similar to the first component is also a second component. And / or the term includes any item of the items described concerning the combination or plurality of the plurality of related items disclosed.
[43]
It understood that when one element is described as being "connected" or "coupled" to another element, but may be directly connected or coupled to the other components, may be other element in between It should be. In contrast, when an element is referred to there being "directly connected" to another element or "directly connected", it should be understood that other components in the middle that does not exist.
[44]
The terms used in the present specification are merely used to describe particular embodiments, and are not intended to limit the present invention. Expression in the singular number include a plural forms unless the context clearly indicates otherwise. In this application, the terms "inclusive" or "gajida" terms, such as is that which you want to specify that the features, numbers, steps, actions, components, parts, or one that exists combinations thereof described in the specification, the one or more other features , numbers, steps, actions, components, parts, or the presence or possibility of combinations thereof and are not intended to preclude.
[45]
With reference to the accompanying drawings, it will be described in detail preferred embodiments of the invention. The same reference numerals for the same components on the accompanying drawings and the description redundant with respect to the same elements will be omitted.
[46]
[47]
Figure 1 is a block diagram showing an image encoding apparatus according to an embodiment of the present invention.
[48]
1, the image encoding device 100 includes a picture dividing unit 110, a prediction unit (120, 125), the conversion unit 130, a quantization unit 135, a reordering unit 160, an entropy coding unit ( 165), it may include an inverse quantization unit 140, an inverse transformation unit 145, filter unit 150 and memory 155. the
[49]
FIG constituent parts shown in Fig. 1 does not mean that each independently shown to represent another characteristic feature, made of an constituent parts are separate hardware or a software unit in the image encoding apparatus. That is, the respective constituent parts combined addition of convenience, each of the configuration of at least one constituent part that includes the list part two configurations described or made part a configuration, it is possible to perform a divided parts of one configuration addition plurality of configuration functions for each of these one is included in the scope of the present invention configured without departing from the spirit of the present invention, examples of an integrated and separate exemplary embodiment portion.
[50]
In addition, some of the components are not the essential components that perform essential functions in the present invention can only be an optional component to improve the performance. Structure of the present invention can only be implemented to include only the essential component parts to implement the essence of the present invention except for the components that are used to improve performance, including only optional configuration required components except the elements that are only used for better performance It is also included in the scope of the present invention.
[51]
A picture dividing unit 110 can divide an input picture into at least one processing unit. At this time, in units of prediction unit may be: (CU Coding Unit) (Prediction Unit:: PU) may be a, a translation unit (TU Transform Unit) and may be a coding unit. Picture division section 110 into a plurality of coding unit, a prediction unit, and the combination of the transform unit for the one picture and a predetermined reference (for example, a cost function), as a coding unit, a prediction unit and a translation unit, a combination to select it can be encoded in the picture.
[52]
For example, one picture can be divided into a plurality of coding units. Coding in order to divide the unit of encoding in a picture may be used a recursive tree structure, such as a quad tree structure (Quad Tree Structure) by one of the picture or the maximum size of the encoding unit (largest coding unit) to the root which is divided into different coding units unit may be divided to have the child nodes as many as the number of the divided coded unit. In accordance with a predetermined limit that is no longer divided coding unit is a leaf node. That is, if we assume that the square divided only possible for one of the coding unit, a coding unit may be divided into up to four different coding units.
[53]
Hereinafter, embodiments in the coding unit of the present invention may be used to mean a unit for performing the encoding, it can be used to mean a unit for performing the decoding.
[54]
Prediction unit may be divided to have the form of at least one of the square or rectangle of the same size within a coding unit, one of the any of the prediction unit of the divided prediction unit in the coding units prediction of other It may be partitioned to have a unit with a different shape and / or size.
[55]
If not the minimum coding unit when generating a prediction unit which performs intra prediction based on the encoding unit may perform intraprediction not divided into a plurality of NxN prediction unit.
[56]
Prediction unit 120, 125 may comprise an intra predictor 125 to perform the inter-prediction unit 120 and the intra-prediction for performing inter-prediction. For the prediction unit whether to use the inter prediction or decision whether to perform intra prediction, it is possible to determine the specific information (e.g., intra-prediction modes, motion vectors, reference picture, and so on) for each prediction method. At this time, the prediction process unit is performed and the prediction method and the specific process unit to be the content determined may be different. For example, the prediction method and the prediction mode and the like is determined as a prediction unit, for performing prediction may be performed in a conversion unit. Residual values ​​between the generated prediction block and the original block (residuals block) can be input to the converter 130. Further, the prediction mode information used for prediction, and motion vector information which are coded by the entropy coding unit 165 together with the residual value may be delivered decoding groups. When using a specific encoding mode, instead of generating a prediction block by the prediction unit (120, 125), by directly coding the source block it is also possible to transfer the decrypting unit.
[57]
Inter prediction section 120 thus is predicted based on the information of a part of the coding in the current picture is complete, if the current and of the previous picture or a subsequent picture of the picture also at least predicting the prediction unit, based on information in the one picture, It may predict the unit. Inter prediction section 120 may include a reference picture interpolation, motion prediction unit, a motion compensation unit.
[58]
The reference picture interpolation may receive service information from the reference picture memory 155, it generates the pixel information of more than integer pixels in a reference picture. Can be used for luminance pixel, quarter-8-tap interpolation filter (DCT-based Interpolation Filter) in the DCT-based otherwise the filter coefficient to generate the pixel information of the integer pixels in units of pixels or less. For the color difference signals is 1/8 4-tap interpolation filter (DCT-based Interpolation Filter) in the DCT-based having different filter coefficients on a pixel-by-pixel basis to generate the pixel information of integer pixels or less can be used.
[59]
A motion prediction unit may perform motion estimation based on the reference picture in a reference picture interpolation by the interpolation. There are various methods as a way to calculate a motion vector (Full search-based Block Matching Algorithm) FBMA, TSS (Three Step Search), NTS (New Three-Step Search Algorithm) or the like can be used. A motion vector may have a motion vector value of 1/2 or 1/4 pixel units on the basis of the interpolation pixel. The motion predictor by different motion prediction methods to predict the current prediction unit. Motion predicting method in the skip (Skip) method, merge (Merge) method, AMVP (Advanced Motion Vector Prediction) method, such as an intra block copy (Intra Block Copy) method can be used a variety of methods.
[60]
Intra predictor 125 may generate the pixel information of the current prediction unit based on the reference pixel information of neighboring blocks in the current picture. If it is, the neighboring blocks of the prediction unit then blocks the performing inter-prediction, the reference pixel is a pixel which performs the inter-prediction, with reference of the reference pixel contained in the block performing the inter prediction performs intra prediction for the neighboring blocks of pixels It may be replaced by information. In other words, if reference pixels are not available, it may be replaced by at least one reference pixel in the reference pixels available for reference information that is not available pixels.
[61]
In the intra-prediction mode, prediction may have a non-directional mode that does not use the directional information for the performance of the directional prediction mode, the prediction using the reference pixels in accordance with information on a prediction direction. And a mode for predicting the mode and color difference information to predict the luminance information may be different, it is possible to take advantage of the intra-prediction mode information or the prediction luminance signal information used to estimate the brightness information to estimate the color difference information.
[62]
Intra-prediction for a case the same size of the size of the translation unit of the prediction unit when performing the intra prediction, a pixel that exists on the left side of the prediction unit, and the pixel, the prediction unit based on the pixels existing in the top of existing in the upper left the can be performed. But it can be when the size of the prediction unit to perform the intra-prediction size and phase conversion unit, using the reference pixel on the basis of a conversion unit to perform intra prediction. It is also possible to use the intra-prediction using the NxN split only for the minimum coding unit.
[63]
Intra-prediction method may generate a prediction block after applying (Adaptive Intra Smoothing) AIS filter the reference pixels according to the prediction mode. Type of AIS filters that are applied to the reference pixel may be different. The intra-prediction mode of the current prediction unit for performing intra prediction method may be predicted from the intra-prediction mode of the prediction unit existing in the vicinity of the current prediction unit. When prediction a prediction mode of the current prediction unit using the mode information predicted from the surrounding prediction unit, the intra prediction mode is the same when using the predetermined flag information, the current prediction unit and the surrounding prediction unit for the current prediction unit and the surrounding prediction unit a prediction mode and to transmit the same information that, if the can when the prediction mode of the current prediction unit and the peripheral units of different prediction by performing the entropy coding to encode the prediction mode information of the current block.
[64]
In addition, a residual block that contains the prediction section 120, 125 predicted by performing a prediction based on a prediction unit of the unit to the original block of the prediction unit and the difference value of the residual values ​​(Residual) information generated by the can be generated. The generated residual block may be input to the converter 130.
[65]
Conversion unit 130 in the source block and the prediction unit (120, 125) (Discrete Cosine Transform), DCT residual block including residual value (residual) information of the predicted unit generation via, DST (Discrete Sine Transform), KLT and using the same conversion method can be converted. To apply the DCT transform to the residual block, the intra-prediction mode information of the prediction unit used to generate the residual block might seem apply to apply the DST or KLT can be determined based on.
[66]
The quantization unit 135 may quantize the values ​​converted into the frequency domain in a transform unit 130. The Based on the importance of the image or depending on the block quantization coefficient it may be varied. A value calculated by the quantization unit 135 may be provided to the inverse quantization unit 140 and the reordering unit 160.
[67]
Reordering unit 160 may perform the reordering of the coefficient value for the quantized residual values.
[68]
Rearrangement unit 160 may change the form factor of the two-dimensional block by a coefficient scanning method (Coefficient Scanning) in the form of a vector of 1 dimension. For example, the rearrangement unit 160, the zig-zag scanned using a scan (Zig-Zag Scan) method from the DC coefficient to the coefficients of the high frequency region can be changed to a one-dimensional vector format. May be used instead of the horizontal scanning to scan zag scan vertical scan to scan two-dimensional coefficients of the block type in the column direction, the block coefficient of the two-dimensional form in the row direction according to the size of the transformation unit and the intra prediction mode jig. That is, according to the size and the intra-prediction mode of the conversion unit of zig-zag scanning may determine whether, any scanning method of the vertical scan and the horizontal scan will be used.
[69]
The entropy encoding unit 165 may perform entropy-encoding on the basis of the value calculated by the reordering unit 160. The Entropy encoding, for example, exponential Golomb (Exponential Golomb), may be used for various coding methods such as CAVLC (Context-Adaptive Variable Length Coding), CABAC (Context-Adaptive Binary Arithmetic Coding).
[70]
The entropy encoding section 165 rearrangement unit 160 and the prediction unit (120, 125) from the residual value of the coefficient of the coding unit information and block type information, prediction mode information, the division unit information, a prediction unit of information and transmission unit information, motion vector information, and reference frame information, interpolation information, filter information of the block can be encoded in a variety of information.
[71]
The entropy coding unit 165, the entropy encoding may be the coefficients of a coded unit of input in the rearrangement unit 160. The
[72]
The inverse quantization unit 140 and inverse transform unit 145 inverse quantizes the values ​​quantized by the quantization unit 135 and inverse transform the values ​​converted by the conversion unit 130. Residual value (Residual) generated by the inverse quantization unit 140 and inverse transformation unit 145 is the prediction unit restoring combined with the motion estimator, a motion compensator, and intraprediction predicted through parts prediction unit comprises a (120, 125) it is possible to produce a block (block Reconstructed).
[73]
Filter unit 150 may include at least one of a deblocking filter, offset correction, ALF (Adaptive Loop Filter).
[74]
De-blocking filter may be removed and the resulting block distortion due to the interface between the block in the reconstructed picture. To perform a de-blocking can be determined whether or not to apply the deblocking filter to the current block based on pixels included in several rows or columns included in the block in order to determine. For the application of the deblocking filter to the block can be applied in a strong filter (Strong Filter) or a weak filter (Weak Filter) in accordance with the necessary de-blocking filter strength. Also note that when applying the deblocking filter for vertical filtering and horizontal filtering can be done in parallel for processing the horizontal filter and vertical filter.
[75]
Offset compensation unit for performing a de-blocking the image it is possible to correct the offset of the original image in pixels. Offset and then divided into the area of ​​the number of certain of the pixels included in the image to perform the offset correction for the specified picture determines the area to perform the offset considering a method of applying an offset to the area or edge information of each pixel you can use the method of applying.
[76]
(Adaptive Loop Filtering) ALF may be performed on the basis of a comparison of the original picture and the filtered reconstructed image value. Divide the pixels included in the image in a predetermined group can be performed by determining the differential filter as a single filter to be applied to the group for each group. Information relating to whether to apply the ALF is a luminance signal is shaped, and the filter coefficients of the filter to be applied in accordance with the ALF coding unit (Coding Unit, CU) each block can have, to be transmitted by each may vary. Further, the application may be applied to the ALF filter of the same type (fixed type) regardless of the characteristics of the current block.
[77]
Memory 155 may store the reconstructed picture block or output through a filter section 150, the stored recovery block or picture may be provided at the time of performing inter-prediction predictor (120, 125).
[78]
[79]
Figure 2 is a block diagram showing an image decoding apparatus according to an embodiment of the present invention.
[80]
2, the video decoder 200, an entropy decoding unit 210, a reordering unit 215, an inverse quantization unit 220, an inversion unit 225, a prediction unit (230, 235), the filter unit ( 240), may be included in the memory 245.
[81]
If the video bit streams from the video encoder input, the input bit stream can be decoded in the process of a video encoder and opposite.
[82]
The entropy decoding unit 210 may perform entropy decoding in the reverse procedure to that performing the entropy coding in the entropy coding unit of the video encoder. For example, it is possible to correspond to the process performed in the video encoder be subject to a variety of methods such as exponential Golomb (Exponential Golomb), CAVLC (Context-Adaptive Variable Length Coding), CABAC (Context-Adaptive Binary Arithmetic Coding).
[83]
The entropy decoding unit 210, the can decrypt the information with regard to intra-prediction and inter-prediction performed in the encoder.
[84]
Reordering unit 215 may perform reordering based on the way rearrange the entropy decoded bitstream in the entropy decoding unit 210 in the encoding unit. The coefficients represented as one-dimensional vector form may be further rearranged to restore it to the coefficients of the blocks in the form of two-dimensional. Reordering unit 215 by the received provided information related to the coefficient scanning performed on the coding unit based on the scanning procedure performed in the encoding unit may perform reordering by a method of scanning in reverse.
[85]
The inverse quantization unit 220 may perform inverse quantization based on the count value of the reordered block and the quantization parameter provided by the encoder.
[86]
Inverse transform unit 225 may be for a conversion that is, DCT, DST, and KLT performed in converting unit for performing a quantization result by the image encoder performs the inverse transformation that is, reverse DCT, reverse DST and inverse KLT. The inverse transform may be performed on the basis of the transmission unit is determined from the video encoder. The inversion unit 225 of the video decoder prediction method, the transformation method (e.g., DCT, DST, KLT) based on the current block of the plurality of information such as the size and direction of prediction can be carried out selectively.
[87]
Predictor (230, 235) may generate a prediction block based on a previously decoded block, or picture information provided by the entropy decoding unit 210, a prediction block generated additional information and the memory 245 provided in the.
[88]
Present on equally to the operation of the video encoder, the size of the size and the conversion unit of the prediction unit of the same when performing the intra prediction, pixel, the upper present in the pixels, the upper left corner existing on the left side of the prediction unit as described above, on the basis of pixels that performs intra-prediction for a prediction unit, however, the case where the size of the transformation unit of the prediction unit for the performance of intra prediction different, using a reference on the basis conversion units of pixels to perform the intra prediction can. It is also possible to use the intra-prediction using the NxN split only for the minimum coding unit.
[89]
Predictor (230, 235) may include predicting unit determining unit, an inter prediction unit and the intra-prediction unit. Prediction unit judging section receives a variety of information such as the motion prediction information of the entropy decoding unit 210, prediction unit information, the intra-prediction method to be input in the prediction mode information and inter-prediction method of the separate prediction unit of the current coding unit, and prediction if the unit is performing inter prediction or it can be determined whether to perform intra prediction. The inter-prediction unit 230 is provided in the video encoder using the information necessary for inter-prediction of the current prediction unit are predicted on the basis of the information contained in the at least one picture of the previous picture or a subsequent picture of a current picture containing the current prediction unit It may perform inter prediction on the unit. It may perform inter-prediction based on the information of the restored partial area - or, a group within a current picture containing the current prediction unit.
[90]
Motion predicting method in the prediction unit included in the coding unit, based on the coding units for performing inter-prediction is a skip mode (Skip Mode), merge mode (Merge mode), AMVP mode (AMVP Mode), the intra-block copy mode of what kind of method can determine whether or not.
[91]
An intra prediction unit 235 may generate a prediction block based on a pixel information in the current picture. When the prediction unit of the prediction unit that performs intra prediction, based on the intra-prediction mode information of the prediction unit provided in the video encoder to perform intra prediction. An intra prediction unit 235 may include a (Adaptive Intra Smoothing) AIS filter, the reference pixel interpolating units, DC filter. AIS filter may be applied to determine whether a filter is applied in accordance with the prediction mode of the current prediction unit as a part that filters the current block of the reference pixel. Using the prediction mode information of the prediction filter and the AIS unit provided in the video encoder may perform the AIS filtering the current block of the reference pixel. If the current mode is a prediction mode of the block does not perform filtering AIS, AIS filter can not be applied.
[92]
Reference pixel interpolation unit may if the prediction mode of the prediction unit of one prediction unit which performs intra prediction based on the pixel value interpolation reference pixels, by interpolating the reference pixel to generate a reference pixel of a pixel unit or less constant value. If the prediction mode of generating a predictive block without the prediction mode of the current prediction unit interpolates the reference pixels a reference pixel can not be interpolated. DC filter has a prediction mode of the current block to generate a prediction block through the filter when the DC mode.
[93]
The reconstructed block or picture may be provided to filter unit 240. Filter unit 240 may include the deblocking filter, offset correction, ALF.
[94]
From the video encoder can be provided with information and di was applied when the blocking filter, information on whether the applied strong filter or apply a weak filter to whether on whether or not applying the deblocking filter to the block or picture. The deblocking filter of a video decoder being provided for the de-blocking filter-related information provided from the video encoder may perform deblocking filtering on the block in the video decoder.
[95]
Offset correcting unit may perform the offset correction on the restored image based on the information such as the type and the offset value of the offset compensation applied to the video encoding operation.
[96]
ALF may be applied to the encoding unit on the basis of whether the ALF application provided from the encoder information, ALF coefficient information, and the like. The ALF information may be provided to include a particular parameter set.
[97]
Memory 245 stores the reconstructed picture blocks or can to be used as a reference picture or a reference block may also provide the reconstructed picture as an output module.
[98]
In the following embodiments, the present invention as described above, used as a term for convenience coding unit (Coding Unit) coding units of description, but the encoding may be not only a unit for performing the decoding.
[99]
Also, the current block, to indicate the coding / decoding the current block, the encoding / accordance with the decoding phase, the coding tree block (or coding tree unit), an encoding block (or encryption unit), the conversion block (or a conversion unit), or prediction block It can be an indication or the like (or the prediction unit).
[100]
[101]
One picture can be divided into the basic blocks of the square or non-square shape encoding / decoding. In this case, the basic blocks may be referred to as the coding tree unit (Coding Tree Unit). Coding tree unit may be defined as the largest size allowed by the encoding unit sequence or a slice. Coding tree unit information related to the size of the square or non-square shape and whether or coding tree unit may be signaled through a sequence parameter set, picture parameter set or a slice header and the like. Coding tree unit may be divided into a smaller size for the partition. In this case, if the generated partition tree by splitting a coding unit as to the depth 1, the partitions created by dividing the depth of 1 partitions can be defined as the depth 2. That is, by dividing the generated within the depth k of the partition tree coding unit partition may be defined as having a depth k + 1.
[102]
Coding tree unit may be defined as a coding unit for partitioning the generated arbitrary size as the split. The coding unit is divided or recursively, may be divided into a basic unit for performing a predictive, quantized, transformation, or in-loop filtering, and the like. For example, any size of the partition generated as the coding units is split may be defined or the coding unit, defined as the predicted, quantized, transformation, or the basic unit of conversion unit or a prediction unit for performing such loop filter.
[103]
Partitioning of the coding tree unit or a coding unit, a vertical line may be performed based on at least one of (Vertical Line) or horizontal (Horizontal Line). In addition, the number of vertical and horizontal lines that partition the coding tree unit or a coding unit may be at least at least one. For example, as a vertical line, or one with a horizontal line, the coding tree unit or dividing the coding unit into two partitions, or two vertical and two by a horizontal line, the three partitions the coding tree units or coding unit It can be split. Or, by using a single vertical line and one horizontal line, it is possible to divide the coding tree units or coding unit to the four partitions of the length and width of one-half.
[104]
If the coding tree units or coding unit by using at least one vertical or at least one horizontal line is divided into a plurality of partitions, the partitions may have a uniform size, or may have a different size. Alternatively, it may also be any one of the partitions have a different size from the rest of the partition.
[105]
In the embodiments to be described hereinafter, the coding tree units or coding unit is assumed to be divided into a quad tree or a binary tree structure. However, it can also be further divided in the coding tree units or coding unit by using a large number of vertical line or a larger number of horizontal lines of the.
[106]
Figure 3 illustrates an example of dividing the one embodiment to which the present invention is applied, coded block on the basis of the tree structure (tree structure) in a hierarchical manner.
[107]
The input video signal is decoded by a predetermined block unit, the basic unit is referred to as a coded block for decoding Thus the input video signal. Coding block may be a unit for performing the intra / inter-prediction, transformation, quantization. Further, the coding block unit prediction mode is determined (e.g., the intra-prediction mode or the inter-prediction mode), the prediction block included in the coded blocks, it is possible to share the determined prediction mode. Coded block may be a square or non-square blocks of arbitrary size of 8x8 to 64x64 belonging to the range, it can be 128x128, 256x256, or a square or non-square block having a size more.
[108]
Specifically, the coding block can be divided into a hierarchical tree based on at least one of a quad (quad tree) with a binary tree (binary tree). Here, the division of the quad-tree based 2Nx2N block coding scheme is a split of a binary tree-based divided into four NxN coded block may represent a method of coding a block is divided into the two coded blocks. Although the division of a binary tree-based were carried out, in the lower depths may be present in the square in the coding block.
[109]
Dividing the binary tree-based may be performed symmetrically, and may be performed asymmetrically. The coded blocks divided by a binary tree-based block may be a square, but may be non-square block such as a rectangular. For example, as shown in the example in shown in Figure 4 the partition shape which the division of a binary tree-based allow, symmetric (symmetric) of 2NxN (horizontal non-square coding unit) or Nx2N (vertically non room coding unit), an asymmetric of the type (asymmetric) in nLx2N, nRx2N, 2NxnU 2NxnD or it may include at least one.
[110]
Division of the binary tree-based and may be limited to allow only one of a symmetric or asymmetric form of partition. In this case, it is for constituting the coding tree unit, a square block for the quadtree partitioning CU, configure coding tree unit, in a non-symmetric square block may correspond to a binary tree partitioning. What constitutes a tree-coding unit in a square block with symmetric non-square block may correspond to a quad, and a binary tree CU partitioning.
[111]
Dividing the binary tree-based may be performed on a coding block is divided in the quad-tree based it is no longer performed. For the coded blocks divided by a binary tree-based partition of the quad-tree based can no longer be performed.
[112]
Further, division of sub-depth may be determined dependent on the division form of the parent depths. If a one embodiment, the partitioning of the binary tree based on more than one depth allows, only a binary tree split and forms the same type of binary tree-based partition of the upper depth, this can be tolerated at lower depths. For example, if the binary tree based on the parent depths to form 2NxN division is carried out, even in the lower depth of the division of a binary tree-based 2NxN form can be carried out. Or, in the case of a binary tree-based Nx2N to form in the upper division depth is carried out, even in the lower depth of the division of a binary tree-based Nx2N shape can be allowed.
[113]
On the other hand, it is also possible to allow at lower depths, only a binary tree split and form different types of binary tree-based partition of the upper depth.
[114]
For a sequence, a slice, the coding tree unit or a coding unit, may be limited to only a particular form of binary tree-based partitioning is used. For example, it is possible to limit the allowed 2NxN or only division of a binary tree-based Nx2N form for coding tree unit. Partition type may be acceptable to code the information about the partition type that encoder or decoded groups may be defined based, not allowed, or allowed to form partition signaling on the bit stream.
[115]
5 is a view showing an example in which only a particular form of binary tree-based partition allowed. Figure 5 (a) represents an example that only a limited partitioning of the binary tree based Nx2N This allows, also (b) the 5 shows an example that only a limited partitioning of the binary tree based 2NxN This allowed. Indicating the division of the information, a binary tree based on the size / depth of the quad-tree or a binary tree-based adaptive that this information, quad split tree-based allow for instructing the division of the quad-tree basis to implement the partition coded block for information, a binary tree based on whether the division is the division of information or a binary tree based on the size / depth of the information, a binary tree-based coding block is divided is not permitted for the size / depth of the coded blocks which allow the vertical direction or include information about whether the horizontal direction may be used.
[116]
Further, a coding tree unit or for a given coding unit, a binary tree, the number of times the division is permitted, a binary tree split, such as the number of depth or a binary tree, the split allows the depth is allowed to be obtained. The information may be transmitted via the group decoding, the bitstream is coded in the coding tree unit or units of the coding unit.
[117]
For example, it is through the bit stream, the syntax 'max_binary_depth_idx_minus1' represents the maximum depth that a binary tree segmentation is allowed to be coded / decoded through the bit stream. In this case, max_binary_depth_idx_minus1 + 1 may point to a maximum depth which is a binary tree split allowed.
[118]
Referring to Figure 6, in the example illustrated, shown as a in Fig. 6, a binary tree split for the depth 2 encoding unit 3 and the depth of the coding units performed. Accordingly, the coding tree unit in the binary tree splitting is carried out a number of times (twice), representing the information, the coding tree unit in the binary tree splitting the maximum allowed depth information or coding tree unit indicating (depth 3) in the binary tree split the number of acceptable depth at least one of information indicating (2, depth 2, depth and 3) can be encoded / decoded by the bitstream.
[119]
As another example, a binary tree split is allowable number of times, at least one of the number of the binary tree or a binary tree split the depth segmentation is allowed to be acceptable depth may be obtained by sequence slice. For example, the information, is encoded in a sequence, picture or slice units may be transmitted on a bit stream. Accordingly, it is possible to the first slice and the second slice, a binary tree split count, a binary tree split, at least one of the number of maximum depth or a binary tree depth is divided allowed allowed disparity. For example, in the first slice, while the one which is allowed only in a binary tree split depth, the second slice, a binary tree split can be tolerated in the two depths.
[120]
In yet another example one slice or picture time the level identifier (TemporalID) in accordance with a binary tree split the permitted number, the binary tree segmentation is allowed depth or a binary tree split is acceptable may differently set at least one of a number of depth that is to be the have. Here, the time the level identifier (TemporalID), the point (view), the space (spatial), time (temporal) or the image quality (quality) of the at least one scalability (Scalability) for identifying a plurality of layers each image having a will be.
[121]
3, the depth divided (split depth) k is the first coding block 300 may be divided into a plurality of second coding block based on the quad-tree (quad tree). For example, the second coding block 310 to 340 is a square block that has a half size of the width and height of the first coded block, dividing the depth of the second coded block can be increased to k + 1.
[122]
Dividing the depth k + 1 of the second coding block 310 may be divided into a plurality of third code block division depth of k + 2. Second dividing the coding block 310 can be carried out according to the division method by selectively using any one of the quart tree or a binary tree. Here, the division method may be determined based on at least one of information indicating a division of the divided information or a binary tree-based indicative of a quadtree-based.
[123]
The second coding block 310 two quarts case that is divided into a tree-based, the second coding block 310 is divided into four third coded block 310a having a half size of the width and height of the second coded block, the third coded block 310a dividing the depth may be increased to k + 2. On the other hand, in a case that is divided into second coding block 310 is a binary tree based on the second coding block 310 may be divided into two third block coding. At this time, each of the two third coded block is one half the size of the non-square blocks of the width and height of the second coded block, split-depth can be increased to k + 2. The second coded block according to the dividing direction may be determined in a non-square block in the transverse direction or the longitudinal direction, dividing direction may be determined based on information on whether the division of a binary tree-based portrait or landscape orientation.
[124]
On the other hand, the second coding block 310 may be determined by end-coded blocks which are no longer dividing, based on the quad-tree or a binary tree, in this case, the coding block may be used as a predicted block or a transform block.
[125]
Third coding block 310a of the second terminal or determined by the coding block dividing, like the coding block 310 and may be further divided based on the quad-tree or a binary tree.
[126]
On the other hand, the three coded blocks divided by a binary tree-based 310b are further based on a binary tree may be further divided into the coding blocks (310b-2) or a coded block (310b-3) in the horizontal direction in the vertical direction, the coding division depth of the block can be increased to k + 3. Alternatively, the third coded block 310b based on the binary tree further may be determined by non-dividing end-coded block (310b-1), In this case, the coding block (310b-1) can be used as a predicted block or a transform block can. However, the above-described segmentation process allows the division of information or a binary tree based on the size / depth of the information, a binary tree-based coding block is divided is allowed on the size / depth of the coded blocks allowed the division of the quad-tree based on the size / depth of the non-coded block may be performed in a limited based on at least one of information.
[127]
Size of the coding block can have, or are limited to a predetermined number, the size of the unit within the predetermined coding blocks may have a fixed value. For example, the size or the size of the coding block of the picture within the coded block sequences, can be limited to 256x256, 128x128 or 32x32. The information indicating the size of the sequence or the picture within the coding block may be signaled by a sequence header or picture header.
[128]
Division result based on the quad-tree and tree-by battery, the coding unit may ttil a rectangle or square of any size.
[129]
[130]
Coding block is a skip mode, and is coded using the intra prediction, at least one of the prediction method or inter-picture skipped. If the coding block is determined, it can be divided through the prediction of the coding block to determine the predicted block (Block Prediction). Prediction of the coding block dividing may be performed by a partition mode (Part_mode) showing a split in the form of coded blocks. Size or shape of the prediction block may be determined according to a partition mode of the coded block. For example, the size of the prediction block, which is determined according to the mode partition can have the same or a smaller value as the size of the coding block.
[131]
7 is a diagram illustrating a partition mode that can be applied to the coded block when the coded block is coded in inter picture prediction.
[132]
If the coding block coded by inter picture prediction, coding block, as shown in the example in shown in Figure 7, any of the eight partition mode can be applied.
[133]
If the coded blocks are coded with intra picture prediction, the coding block may be subject to a partition mode PART_2Nx2N or PART_NxN.
[134]
PART_NxN is applicable when the coded blocks having the minimum size. Here, the minimum size of the coding block can be defined based on the encoder and decoder. Alternatively, information on the minimum size of the coding block may be signaled through a bitstream. For example, the minimum size of the coding block is signaled through the slice header, and therefore, a minimum size of the coding block can be defined by each slice.
[135]
In general, the size of the prediction block may have a size of from 64x64 4x4. However, if the coded block coded by inter picture prediction, when performing motion compensation, to reduce the memory bandwidth (memory bandwidth), it is possible to prevent the prediction blocks have a 4x4 size.
[136]
[137]
8 is a group according to an embodiment to which the present invention is applied, a video coder / decoder groups - shows a kind of definition of an intra-prediction mode.
[138]
Video coder / decoder group may perform intra prediction by using any one of a defined intra-prediction mode. Group for intra-prediction-intra-prediction mode defined may be of a non-directional prediction mode (e.g., Planar mode, DC mode) and 33-directional prediction mode (directional prediction mode).
[139]
Alternatively, the directional prediction modes of a greater number than 33 directional prediction modes can be used to improve the accuracy of intra prediction. That is, it can further subdivide the angle (angle) of the directional prediction mode defines the M number of the extended-directional prediction mode and (M> 33), group-a predetermined angle using at least one of a definition of 33-directional prediction mode It can be used to derive the directional prediction mode with.
[140]
35 the larger number of intra prediction modes than the intra-prediction mode shown in Figure 8 may be used. For example, the more granular the angle of the directional prediction mode, or using at least one of a directional mode of the predetermined number of defined group, it decodes the directional prediction modes with a predetermined angle, a large number of more than 35 intra-prediction mode of You may use the intra-prediction mode. In this case, the use of a greater number than 35 intra-prediction mode of intra prediction modes may be referred to La extended intra-prediction mode.
[141]
9 is an example of the extended intra-prediction mode, the extended intra-prediction mode may be composed of two non-directional prediction mode, the 65 extended-directional prediction mode. The extended intra-prediction mode may equally be used for the luminance components and the chrominance components, it is also possible to use different numbers of intra prediction modes for each other by each component. For example, the luminance component using the 67 extended intra-prediction mode, the color difference component can be used for intra-prediction mode 35.
[142]
Or, using the intra-prediction mode of a different number, depending on the chrominance format (format) may perform intra prediction. For example, a 4: 2: when the 4 format: performing intra-prediction using a 67 intra-prediction mode in the case of 0 format includes the luminance component and the chrominance component may use the 35 intra prediction modes, 4:04 in all, the luminance components and the color difference component by using the intra-prediction mode 67 intra-prediction may also be used.
[143]
Alternatively, depending on the size and / or shape of the block can each other by using the intra-prediction mode of a different number of performing the intra prediction. That is, using a 35 intra-prediction mode or the intra-prediction mode 67, depending on the size and / or shape of the PU or CU may perform intra prediction. For example, the size of the CU or PU is less than 64x64 or asymmetric partitions if (asymmetric partition) is using the 35 intra prediction modes, and can perform the intra-prediction, the CU or PU size equal to 64x64, or larger case may perform intra prediction by using a 67 intra-prediction mode. In Intra_2Nx2N may allow the 65 intra prediction modes, the Intra_NxN may only be 35 directional intra-prediction mode.
[144]
Sequence, each picture or slice, it may be differently set the size of the block to apply the extended intra-prediction mode. For example, the first slice in the, in the set to be applied to the intra-prediction mode, extended to larger blocks than 64x64 (e.g., CU or PU), the second slice set so that the intra-prediction mode, extended to larger blocks than 32x32 applied can. Information indicating the size of the block in which the extended intra-prediction mode is applied, can be signaled by a sequence, picture or slice units. For example, information indicating the size of which is the extended intra-prediction mode applied to a block may be defined as a 'log2_extended_intra_mode_size_minus4' by subtracting the integer 4 after taking the logarithm of the size of the block. For example, it is the value of log2_extended_intra_mode_size_minus4 is 0, it indicates that it is possible to apply the intra-prediction mode, extended to a block having a larger size than the block or 16x16 with 16x16 or larger, the value of the log2_extended_intra_mode_size_minus4 1, 32x32 or more size a has may indicate that block, or can be applied to the extended intra-prediction mode in a block having a size larger than 32x32.
[145]
In consideration of the above, the color difference component, the color difference format, at least one of size or shape of the block described above, it may be determined if the number of intra-prediction mode. Beyond the described example, the encoding / decoding block to the intra prediction mode, intra prediction mode, which is used to determine which of the candidate (e.g., the number of MPM) on a road, a color difference component, the color difference format, at least one of size or shape of the block It may be determined in accordance with. Reference to the drawings will be described below by using the encoding / decoding method for determining the intra-prediction mode of the target block and the intra-prediction mode is determined, and a look at how to perform intra prediction.
[146]
[147]
Figure 10 is one embodiment to which the present invention is applied, a flow chart schematically showing the intra-prediction method.
[148]
10, it is possible to determine the intra-prediction mode of the current block (S1000).
[149]
Specifically, the intra-prediction mode of the current block may be derived based on the candidate list with the index. Here, the candidate list includes a plurality of candidates, a plurality of candidates may be determined based on the intra-prediction mode of peripheral blocks adjacent to the current block. Neighboring blocks may comprise a top of the current block, the lower, the left, at least one of the block located on the right side or corner. The index may specify any one of a plurality of candidates that belong to the candidate list. A candidate specified by the index may be set to the intra-prediction mode of the current block.
[150]
The intra-prediction mode using neighboring blocks in the intra-prediction can be set as a candidate. In addition, the intra-prediction mode of a similar direction and an intra-prediction mode of the surrounding block may be set as a candidate. Here, the intra-prediction mode of a similar orientation may be determined by the value plus or minus the predetermined constant value in the intra-prediction modes in the neighboring blocks. A predetermined constant value may be one, two or more integer.
[151]
The candidate list may further include a default mode. The default mode may include at least one of the planar mode, DC mode, a vertical mode, a horizontal mode. The default mode may be more adaptively in consideration of the maximum number of candidates included in the candidate list for the current block.
[152]
Maximum number of candidates included in the candidate list is 3, 4, 5, may be six or more. Maximum number of candidates included in the candidate list based video encoder / decoder groups-can be a value set a fixed, may be determined as a variable on the basis of the properties of the current block. Property may refer to the location / size / shape, the block is available number / type of intra-prediction mode, the color-difference property, the color difference format of the block. Or, and information indicating the maximum number of candidates included in the candidate list may additionally be ring signal, it may be a maximum number of candidates included in the candidate list to be determined variably by. Information indicating the maximum number of the candidate may be a ring signal from at least one of the sequence level, picture level, slice level or block level.
[153]
Corresponds to the case of the 35 intra prediction modes defined to be selectively used, conversion to the index corresponding to the intra-prediction mode, extended intra-prediction mode of a neighboring block, or 35 intra-prediction mode-extended intra-prediction mode, the group It is converted into an index that can lead to a candidate. Groups to convert the index - may be defined using a table, a scaling operation based on a predetermined value may be used. Here, the group-defined table may be defined by a mapping relation between the intra-prediction modes are different from each other group (e.g., an extended intra prediction mode 35 and the intra-prediction mode).
[154]
For example, using the left neighboring blocks are 35 intra-prediction mode, when the intra-prediction mode 10 (horizontal mode) of the left neighboring blocks, to be converted to an index 16 corresponding to a horizontal mode in the intra-prediction mode, it extended it can.
[155]
Or, using the intra-prediction mode, the upper neighboring blocks extended and, when the intra-prediction mode index of the upper neighboring block of 50 (vertical mode), to convert it to an index 26 corresponding to vertical mode at 35 intra-prediction mode have.
[156]
The above-described intra-prediction mode and for each determination method the luminance components and the chrominance components on the basis of independently be the intra prediction modes derived, the color difference component may be derived in dependence on intra-prediction mode of the luminance component.
[157]
Specifically, the intra-prediction mode of the color difference component may be determined on the basis of the intra-prediction mode of the luminance component as shown in Table 1.
[158]
TABLE 1
Intra_chroma_pred_mode[xCb][yCb] IntraPredModeY[xCb][yCb]
0 26 10 1 X(0<=X<=34)
0 34 0 0 0 0
1 26 34 26 26 26
2 10 10 34 10 10
3 1 1 1 34 1
4 0 26 10 1 X

[159]
In Table 1 intra_chroma_pred_mode means information that is signaled to a specific intra-prediction mode of the color difference components and, IntraPredModeY shows an intra-prediction mode of the luminance component.
[160]
10, may derive the reference sample for the intra prediction of the current block (S1010).
[161]
Specifically, it is possible on the basis of surrounding samples of the current block to derive a reference sample for the intra prediction. Surrounding the sample may be the means that reconstructed samples of the above-mentioned neighboring blocks, which may be restored after the sample of the in-loop filter to the previous reconstructed samples, or in-loop filter is applied has been applied.
[162]
It may be the surrounding sample restore the current block prior to use as a reference sample, a sample close to the filter based on a predetermined intra-filter may be used as a reference sample. To filter out near the sample by using the intra-filter it may also be referred to as reference sample smoothing (smoothing). The intra-filter may include at least one of the second intra-filter applied to a plurality of peripheral sample located in the first intra-filter or the same vertical line that is applied to a plurality of peripheral sample located in the same horizontal line. And either the first filter or the second intra-intra-filter based on the location of the sample is close to be selectively applied, the two intra-filter may be applied redundantly. In this case, the first may be an intra-filter or a second at least one filter coefficient of the intra-filter (1,2,1), but is not limited to this.
[163]
The filtering may be performed adaptively based on at least one of the size of the conversion block of the intra-prediction mode or the current block of the current block. For example, the filter when the intra-prediction mode of the current block, the DC mode, a vertical mode or horizontal mode can not be performed. If the size of the conversion block NxM, filtering may not be performed. Here, N and M may be the same or may be a value different from one another, 4, 8, 16 or any one of more values. For example, when the size of the transform block is 4x4, the filtering may not be performed. Alternatively, a current block of an intra-prediction mode, a vertical mode (or landscape mode) different from the group of - may be based on a comparison result between the (threshold) defined threshold can optionally perform filtering. For example, it is possible to perform the filtering only when the difference between the intra-prediction mode, the vertical mode of the current block is larger than the threshold value. The threshold may be defined by the size of the transform block as shown in Table 2.
[164]
TABLE 2
8x8 transform 16x16 transform 32x32 transform
Threshold 7 1 0

[165]
The intra-filter image encoder / decoder groups group can be determined by any one of a plurality of intra-defined filter candidates. Of a plurality of candidate intra-filter for this purpose there is a separate index that specifies the intra-filter for the current block can be signaled. Alternatively, it is also an intra-filter determined on the basis of at least one of a current block of the size / shape, the change of the information, or close to the sample on the size / shape of the transform block, the filter strength (strength) (variation).
[166]
10, may perform intra prediction by using the intra-prediction mode, the reference samples in the current block (S1020).
[167]
That is, by using the intra-prediction mode and a reference sample derived from a determined in S1010 S1000 may obtain the prediction samples of the current block. However, it can cause poor image quality of the prediction image problem due to use boundary samples in the case of intra prediction adjacent blocks. Thus, with reference to the calibration procedure it may further involve, and 11 to 13 below for generating the predicted sample using the prediction process described above will be in view at detail. However, the calibration process will be described later that is not limited to be applied only to the intra prediction sample, the sample can be applied to inter-prediction or reconstructed samples. FIG.
[168]
[169]
Figure 11 is one embodiment to which the present invention is applied, on the basis of difference information of the neighboring sample illustrates a method for correcting the predicted samples for the current block.
[170]
On the basis of difference information of the plurality of surrounding samples for the current block it can be corrected prediction samples of the current block. The correction may be performed for all the samples belonging to the current prediction block may be performed only for the prediction sample that belongs to a predetermined partial area of. Some areas may be one line / ten days in a row / column or more, which group for the compensation in the video coder / decoder - may be a motion area. For example, a plurality of row / column correction can be performed from a boundary of one of the rows / columns or the current block is located at the boundary of the current block. Or, some areas may be determined by a variable based on at least one of the current size / shape or the intra-prediction mode of the block.
[171]
Surrounding the sample may belong to at least one of the neighboring blocks in the upper of the current block, the left side, the upper left corner. The number of neighboring samples used for calibration may be two, three, four or more. Location of nearby samples may be determined variably according to the position of the target within the sample prediction compensation current block. Alternatively, some of the surrounding sample has a fixed position regardless of the position of the prediction target sample the correction, and the other may have a variable position depending on the position of the prediction samples subject to correction.
[172]
Difference information of neighboring samples could mean the difference between the samples around the sample, it may mean a value scaled to the difference samples to a predetermined constant value (e.g., 1, 2, 3, etc.). Here, the predetermined constant value can be determined in consideration of the position of the target compensation prediction samples, the position of the column or row to which it belongs prediction samples subject to correction, the position of the prediction samples in the rows or columns and so on.
[173]
For example, by using a difference between the current sample block of the intra prediction mode is the vertical mode is the case, close to the sample adjacent to the left boundary of the current block p (-1, y) and the upper left around the sample p (-1, -1) then it is possible to obtain a final prediction samples as shown in equation 1.
[174]
[Formula 1]

[175]
For example, by using a difference between the current sample block of the intra prediction mode is the horizontal mode is the case, close to the sample adjacent the upper boundary of the current block p (x, -1) and the upper left around the sample p (-1, -1) then it is possible to obtain a final prediction samples as shown in equation 2.
[176]
[Formula 2]

[177]
For example, by using a difference between the current sample block of the intra prediction mode is the vertical mode is the case, close to the sample adjacent to the left boundary of the current block p (-1, y) and the upper left around the sample p (-1, -1) you can obtain the final prediction samples. At this time, may be added to the difference samples to sample prediction, then scaling the difference samples to a predetermined constant value, it may be adding it to the prediction samples. Predetermined constant values ​​used in scaling can be determined differently according to the columns and / or rows. As an example, then it is possible to correct the prediction samples as in equation (3) and equation (4).
[178]
[Formula 3]

[179]
[Formula 4]

[180]
For example, by using a difference between the current sample block of the intra prediction mode is the horizontal mode is the case, close to the sample adjacent the upper boundary of the current block p (x, -1) and the upper left around the sample p (-1, -1) It may obtain the final prediction sample, which is the same as described above in a vertical mode. As an example, it is possible to correct the prediction samples as shown in Equation 5 and Equation 6.
[181]
[Formula 5]

[182]
[Formula 6]

[183]
[184]
Also as an embodiment 12 and 13 to which the present invention is applied, showing the method of correcting the prediction samples based on a predetermined correction filter.
[185]
Based on the peripheral samples and a predetermined correction filter of the prediction target sample the correction can be corrected prediction samples. At this time, around the sample it can be specified by the current line angle (angular line) of the block-directional prediction modes, and may be one or more samples in the same line and the angle prediction correction target sample. Further, around the sample may be a prediction sample that belongs to the current block, may be reconstructed samples belonging to the neighboring blocks in the current block is restored before.
[186]
The number of taps of the compensation filter, the strength (strength) or the filter coefficients, at least one of whether or not, the angle, the periphery of the intra-prediction mode, the directional prediction mode of the current block if the prediction sample is located at the boundary of the current block is target position, correction of the prediction samples subject to correction prediction mode (inter or intra mode) or the block may be determined based on at least one of the size / shape of the current block.
[187]
12, the at least one prediction / reconstructed samples and the final prediction sample by using a predetermined correction filter is located in the lower left corner of the prediction samples subject to correction as shown In Figure 12, if the one-directional prediction mode index of 2 or 34 It can be obtained. Here, the prediction / reconstructed samples of the left lower end may be belonging to the previous line of the line belonging to the prediction samples subject to correction, which may be part of the same block as the current sample, and may be belonging to the surrounding blocks adjacent to the current block.
[188]
Filtering of the prediction samples may only be performed on-line in the block boundary, and may be performed on a plurality of lines. Each line may have at least one compensation filter is different from the number of taps or filter coefficients of the filters used. For example, for the nearest left of the first line with the block boundary (1 / 2,1 / 2) can be used for filters, it can be used in the case of the second line (12/16, 4/16) filter, and the third line cases (14/16, 2/16), and using a filter, may be used in the case of fourth lines (15/16, 1/16) filter.
[189]
Alternatively, the one directional prediction mode index from 3 to 6, if a value between, or between 30 to 33, it is possible to perform filtering on the block boundary as shown in Figure 13, to correct the predicted sample using the correction filter of 3-tap have. Using the correction of the 3-tap filter to the lower left sample, the lower the sample and the correction target prediction sample at the bottom left of a correction target sample prediction samples as input may perform filtering. Location close to the sample used for the correction filter can be differently determined based on the directional prediction mode. The filter coefficient of the correction filter can be differently determined according to a directional prediction mode.
[190]
If a neighboring block is the inter mode has a different correction filter can be applied depending on whether the intra mode. If the surrounding block in intra mode encoding may be used for filtering to give more weight to the prediction samples than if the coding in inter mode. For example, if the intra-prediction mode 34, when a neighboring block is coded in inter mode, when using a (1 / 2,1 / 2) filter and a neighboring block is coded in intra mode (4/16 , you can use the 12/16) filter.
[191]
Current number of blocks of the line that is within the current block filter in accordance with the size / shape (for example, a coding block, a prediction block) may be different. For example, if the current block size to be the case is less than 32x32 or equal to, the performing the filtering only one line in the block boundary, and otherwise, performs filtering on a plurality of lines, including one line in the block boundary may.
[192]
12 and 13 can be applied in the same / similar in the case of using the described one, the extended intra prediction mode based on the case of using the 35 intra prediction modes that are discussed in FIG.
[193]
[194]
Figure 14 is one embodiment to which the present invention is applied, showing the range of the reference samples for the intra prediction.
[195]
Intra prediction of the current block may be performed by using a reference sample derived based on the reconstructed samples included in the neighboring blocks. Here, the sample is restored, the current block indicates that the unit / decoding unit before / decryption is complete, the. For example, the reference sample P (-1, -1), P (-1, y) around the current block (0 <= y <= 2N-1), P (x, -1) (0 <= x < based on at least one of = 2N-1), it can be an intra-prediction for the current block is performed. In this case, all the intra-prediction mode of the current block (e.g., an index of intra-prediction mode, orientation, angle, etc.) or based on at least one of the size of the conversion block of the current block, to selectively perform the filtering for the reference sample can.
[196]
By using the intra-group filter defined in the encoder and decoder may perform the filtering for the reference sample. For example, using the intra-filter filter coefficient (1,2,1) or the intra-filter coefficients (2,3,6,3,2), it can lead to the final reference sample to be used for intra-prediction.
[197]
Alternatively, by selecting at least one of a plurality of candidate intra-filter to perform filtering for the reference sample. Here, the plurality of candidate intra-filter has at least one filter strength, the filter coefficient or the tap (e.g., the number of filter coefficients, the filter length) may be different from each other. A plurality of candidate intra-filter may be defined in a sequence, a picture, a slice, at least one of the block level. That is, the sequences belong to the current block, a picture, a slice, or block can use the same plurality of candidate intra-filter.
[198]
For the following, convenience of description, a plurality of candidate intra-filter includes a first filter and a second intra-intra-filter, the first filter is an intra (1,2,1) 3-tap filter, the second filter is an intra (2,3,6,3,2) assumed to be 5-tap filter.
[199]
When filtering the reference sample by applying the first intra-filter, the filtered reference samples may be derived as the following equation (7).
[200]
[Expression 7]

[201]

[202]

[203]
When filtering the reference sample by applying the second intra-filter, the filtered reference samples may be derived as the following equation (8).
[204]
[Formula 8]

[205]

[206]

[207]
In Equation 7, and 8, x is an integer between 0 and 2N-2, y may be an integer between 0 and 2N-2.
[208]
Alternatively, it is possible to specify any one of a plurality of candidate intra-filter based on the location of the reference samples, and perform the filtering for the reference sample by using this. See, for example, samples that belong to the first range applies to a first intra-filter, and has reference samples belong to the second range may be applied to the second intra-filter. Here, the first range and the second range is, whether close to the boundary of the current block is divided into a reference whether or not, or whether at the top of the current block or or articulated relative to the whether or not the position to the left, close to the corner of the current block whether it can be classified as standard. For example, the reference current block boundary is adjacent to a sample P (-1, -1), P (-1,0), P (-1,1) as shown in Figure 15, ..., P (- 1, N-1) and P (0, -1), P (1, -1), ..., by applying a first intra-filter P (N-1, -1) filter as shown in equation (7) to perform, and that is not currently adjacent to the block boundary, and the other reference samples may perform filtering, such as the second equation (8) by applying the intra-filter a plurality of intra-filter on the basis of the conversion type used in the current block selecting one of the candidates, and can use them to perform the filtering for the reference sample. Here, the conversion type (1) may refer to a conversion technique such as a DCT, DST, KLT, could mean a (2) 2D transform, 1D conversion, conversion mode indicator, such as non-conversion, (3) primary transformation, it may mean the number of conversion as the second conversion. Hereinafter, conversion type for convenience of explanation, it is assumed to mean a conversion technique such as DCT, DST, KLT.
[209]
For example, if the current block is, if the encoded using a DCT is performed filtering with a first intra-filter, and the current block is coded using the DST, use the second intra-filter to perform filtering have. Or, if the current block is, if the encoded using the DCT or DST is performed filtering with a first intra-filter, and the current block is coded using a KLT, use the second intra-filter to perform filtering have.
[210]
Using the selected filter based on the location of the conversion type and a reference sample of the above-described present block may perform the filtering. For example, if the current block is coded using the DCT, the reference sample P (-1, -1), P (-1,0), P (-1,1), ..., P (-1, N-1) and P (0, -1), P (1, -1), ..., P (performs the filtering using a first filter, intra, that reference other than N-1, -1) samples may perform filtering using a second filter intra. If the current block is coded using the DST, the reference sample P (-1, -1), P (-1,0), P (-1,1), ..., P (-1, N-1 ) and P (0, -1), P (1, -1), ..., see perform filtering by P (N-1, -1) is used for the second intra-filter, other than that the sample is 1 may use the intra-filter to perform filtering.
[211]
Reference neighbor block containing the sample conversion type and based on whether or not the same between the present conversion type of the block by selecting any of a plurality of candidate intra-filters, and can use them to perform the filtering for the reference sample. For example, in the case of using the current block and the neighboring blocks have the same conversion type in the case of performing filtering by using a first intra-filter, and the current block and a transform type is different from each other neighboring block has a second intra-filter It can be used to perform the filtering.
[212]
Selecting any one of a plurality of candidate filters on the basis of the intra-type conversion of the neighboring blocks, and can use them to perform the filtering for the reference sample. That is, in consideration of the type of transformation belonging the reference sample block may select the desired filter. For example, as shown in Figure 16, the current block and the block adjacent to the left / bottom left is coded block by using the DCT, when the block adjacent the top / upper right is the coded block using the DST, the left / reference sample adjacent to the left lower part by applying a first reference filter intra performing the filtering, and adjacent the top / upper right samples may perform filtering by applying a second intra filter.
[213]
With a predetermined area unit, the filter available for the zone may be defined. Here, the predetermined area unit of a sequence, a picture, a slice, a block group (e. G., Coding tree unit row), the blocks (e.g., coding tree unit) may be any one of, share one or more filter a separate region may be defined. Reference sample may be filtered using a filter that blocks the current map to the region belongs.
[214]
For example, it is possible, as illustrated in Figure 17, with a different filter to the CTU unit to perform the filtering for the reference sample. In this case, the sequence in the parameter set (SPS) or picture parameter set (PPS), has the sequence or the information indicating whether the picture is to use the same filter, the type of filter used for each CTU, the available intra filter the CTU of candidate there is an index that specifies a filter or the like used can be signaled.
[215]
The above-described intra-filter may be applied to the encoding unit basis. For example, for the reference sample of the surrounding coding unit, the first may be applied to an intra-filter or a second intra filter performs the filtering.
[216]
[217]
When using a directional prediction mode, or DC mode, there is a possibility cause image quality degradation at the block boundary. On the other hand, if the planar mode, the image degradation of the block boundary relative to the prediction mode that has a relatively small advantage.
[218]
Planar prediction, the reference using the sample, the first prediction of the horizontal direction of the image (i.e., the first prediction samples) and the second prediction image (i.e., the second prediction samples) to generate a back, a first prediction image in the vertical direction and it may be performed by weighted prediction to predict the second image.
[219]
Here, the first prediction image is placed in the horizontal direction of the predicted target sample may be generated based on the reference samples adjacent to the current block. In one embodiment, the first prediction image can be generated based on the weighted sum of the reference sample placed in the horizontal direction of the prediction sample, weight applied to each of the reference sample is the distance to prediction samples, or for the current block size, and a it can be determined in consideration. Samples in the horizontal direction are, may include a right side reference sample placed at the right of the left-hand side reference sample and the prediction sample is placed on the left side of the prediction samples. At this time, refer to the right samples, may be derived from the upper reference samples of the current block. For example, see the right sample or derived by copying the value of any one of the upper reference samples, may be derived as a reference sample, such as the upper side of a weighted sum or average value. Here, the upper reference sample, a reference sample is located on the same vertical line with the right side reference sample may be a reference sample adjacent to the upper-right corner of the current block. Or, depending on the position of the prediction samples, the position of the upper reference sample may be determined differently.
[220]
A second predicted image is placed in the vertical direction of the prediction target sample may be generated based on the reference samples adjacent to the current block. For example, the second predicted image may be generated based on the weighted sum of the reference sample placed in the vertical direction of the prediction samples, the weight applied to each of the reference sample is the distance to prediction samples, or for the current block size, and a it can be determined in consideration. The sample located in the vertical directions, and may include a lower reference sample placed at the bottom of the upper side reference sample and the prediction sample is placed on top of the prediction samples. At this time, the lower reference sample, reference sample can be derived from the left of the current block. For example, see the lower sample or derived by copying the value of any one of the left reference sample may be derived in such a weighted sum or average of the left reference sample. Here, the left reference sample, a reference sample is located on the same horizontal line and the lower reference sample may be a reference sample adjacent to the bottom left corner of the current block. Or, depending on the position of the prediction samples, the position of the upper reference sample may be determined differently.
[221]
As another example, it is also possible to derive the right side reference sample and the lower reference sample by using a plurality of reference samples.
[222]
For example, it is possible to use both, lead to the right side reference sample or reference samples to lower the upper left reference samples and the reference samples in the current block. For example, at least one of the right side reference sample or reference samples may be determined in a lower weighted sum or average of the upper reference samples and the reference samples left of the current block.
[223]
Alternatively, it is possible to derive the current block, the upper side reference sample and then calculating a weighted sum or average of the left reference sample, the right side reference sample as a weighted sum or average value of the calculated value and the upper side of the reference sample. When inducing the right reference samples using a weighted sum calculation of the calculated value and an upper reference sample, taking into account the distance between the current block size, position or the right side reference sample and an upper reference sample in the form of a right reference sample of the current block it is possible to determine the weight.
[224]
Further, it is possible to induce a current block, the upper side reference sample and then calculating a weighted sum or average of the left reference sample, the lower reference sample as a weighted sum or average value of the calculated value and the left side of the reference sample. When inducing the right reference samples using a weighted sum calculation of the calculated value with the reference left samples, in consideration of the current block size, the type of the current block, the lower reference sample position or the reference lower sample and the distance between the left reference sample it is possible to determine the weight.
[225]
Position of the right side reference sample or a plurality of reference samples that are used to derive the left reference sample may be fixed and may be changed according to the position of the prediction samples. For example, an upper reference sample, having a locked position as a reference sample adjacent to the upper-right corner of the current block which is located in the same vertical line with the right side reference sample, the left reference sample is a current block which is located on the same horizontal line and the lower reference sample a may have a fixed position as a reference sample adjacent to the lower left corner. Or, in the case of inducing the right side reference sample, reference upper samples, but using a reference sample in a fixed position adjacent the upper-right corner of the current block, the left reference samples are available for the reference sample placed on the same horizontal line and the prediction sample have. When inducing the lower reference sample, see left samples, but using a reference sample in a fixed position adjacent to the bottom left corner of the current block, the upper reference sample may be a reference sample placed at the same vertical line and the prediction sample.
[226]
18 is a view showing an example of using a plurality of reference samples, leads to the right side reference sample or reference samples lower. The current block is assumed to be a block having a size WxH.
[227]
Referring to (a) of Figure 18, first, based on a weighted sum or average value of the current upper side of the reference sample block P (W, -1) and the left reference samples P (-1, H), see lower-right corner of the sample P It may generate a (W, H). Then, the lower right refer to the sample P (W, H) and to the upper reference sample P (W, -1) a base, to generate a prediction target sample (x, y) the right reference sample P (W, y) for the have. For example, a right prediction sample P (W, y) may be computed as a weighted sum or average value of the bottom right of reference sample P (W, H) and an upper reference sample P (W, -1). Further, it is possible to generate a lower reference sample P (x, H) for the target prediction samples (x, y) based on the reference lower-right corner of the sample P (W, H) and the left reference samples P (-1, H) . For example, the lower reference sample P (x, H) may be computed as a weighted sum or average value of the bottom right of reference sample P (W, H) and the left reference samples P (-1, H).
[228]
When the right side reference sample and the lower reference sample is generated by using the generated reference samples, a first prediction of the prediction samples a sample as shown in (b) of FIG. 18 P h (x, y) and the second prediction sample P v may generate the (x, y). In this case, the first prediction sample P h (x, y) is generated based on the weighted sum of the left reference samples P (-1, y) and the right side reference sample P (W, y), the second prediction samples Pv (x , y) may be generated based on the weighted sum of the upper reference sample P (x, -1) and the lower reference sample P (x, H).
[229]
The first position of the reference sample used for generating a prediction image and the second prediction image may vary depending on the size or type of the current block. In other words, it is the position of the upper left reference sample or reference samples are used to derive a reference sample or a right lower side reference sample according to the size or type of the current block vary.
[230]
For example, the current block is derived from a case of the square blocks of NxN in size, and the right reference sample, P (N, -1), see lower sample, can be derived from the P (-1, N). Or, the right side reference sample and the reference sample is lower, it may be converted to P (N, -1), and based on at least one of the weighted sum, average, minimum or maximum value of P (-1, N). On the other hand, if the current block is a non-square shape, the position of the reference sample which is used to derive the right side reference sample and the reference sample in accordance with the lower aspect of the current block may be differently determined.
[231]
19 and 20 is a diagram illustrating determining the right side reference sample and the reference sample for the lower side, a non-square block in accordance with one embodiment of the present invention.
[232]
As with the example in shown in Figure 19, and the current block is (N / 2) For non-square blocks of size xN, on the basis of the upper reference sample P (N / 2, -1), leading to the right side reference sample, a left reference sample P (-1, N) may derive a reference sample on the basis of the lower side.
[233]
Alternatively, the upper reference sample P (N / 2, -1) and the left reference samples P (-1, N) leading to the right side reference sample or reference samples to lower the weighted sum, average, minimum value or based on at least one of the maximum value of You may. For example, P (N / 2, -1) and P (-1, N) leading to the right side reference sample as a sum or a weighted average, or the right side reference sample as a weighted sum or the average between the calculated value and the upper side of the reference sample It can be derived. Or, P (N / 2, -1) and P (-1, N) leading to the lower reference sample as a sum or a weighted average, or a lower reference sample as a weighted sum or the average between the calculated value and the left side of the reference sample It can be derived.
[234]
On the other hand, as shown in the example shown in Figure 20, and the current block is Nx (N / 2) if the size of the non-square blocks, on the basis of the upper reference sample P (N, -1), leading to the right side reference sample, left reference sample on the basis of the P (-1, N / 2), may lead to a lower reference sample.
[235]
Alternatively, the upper reference sample P (N, -1) and the left reference samples P (-1, N / 2) weighted sum, average, minimum or induce the right side reference sample or reference samples based on the lower side at least one of a maximum value of You may. For example, P (N, -1) and P (-1, N / 2) leads to the right side reference sample as a weighted sum or average, or the right side reference sample as a weighted sum or the average between the calculated value and the upper side of the reference sample It can be derived. Or, P (N, -1) and P (-1, N / 2) weighted sum or average of the sample leads to a lower reference, or the lower reference sample as a weighted sum or the average between the calculated value and the left side of the reference sample It can be derived.
[236]
That is, the lower reference sample, the lower left corner reference of the current block is placed on the same horizontal line and the lower reference sample sample or placed in the same vertical line with the right side reference sample is derived as a current based on at least one of the upper reference sample the right side of the block, the right side reference samples, may be derived based on at least one of a reference sample at the bottom left of the current block is placed on the same horizontal line and the right side reference sample and the reference upper right of the current block is placed on the same vertical line or a reference sample the lower sample.
[237]
[238]
First prediction image may be calculated on the basis of the weighted prediction of the reference sample placed on the same horizontal line and the prediction sample. In addition, the second prediction image may be calculated on the basis of the weighted prediction of the reference sample placed on the same vertical line and the prediction sample.
[239]
Not only in the above-described example, the average, minimum or maximum value, such as of reference sample may generate a first prediction image or the second prediction image.
[240]
Whether a prediction sample is contained in a predetermined area within the current block, a method for differently set, or the first lead to the prediction image or the second prediction image is a method of inducing the reference sample according to the size or type of the current block It can be differently set. Specifically, based on the location of the prediction sample and the right, or different from the position of the reference number of samples or reference samples are used to using a lower reference sample to determine or a first prediction image or be used to derive a second predicted image It can be differently set the number of weights or reference samples.
[241]
For example, the right side reference sample to be used when generating the first prediction image by the prediction samples included in a predetermined region is derived using only the upper reference sample, and the first prediction image by the prediction samples contained in the outer predetermined area when generating the reference sample is the right to be used it can be derived based on a weighted sum or average of the upper reference samples and the reference samples left.
[242]
For example, as shown in the example in shown in Figure 19, if the current block is a height of a long non-square block than the width, the current block included in a predetermined region reference (x, y) the right side of the prediction samples of position samples P can be derived from an (N / 2, -1). On the other hand, it contained in a predetermined region outside the current block (x ', y') right side of the prediction samples of the reference sample position is P (N / 2, -1), and a weighted sum or average value of P (-1, N) a it can be converted to the base.
[243]
Or, as in the example in shown in Figure 20, if the current block is a width of a long non-square block than the height, see the lower side of the prediction samples of the location (x, y) included in a predetermined region within the current block samples P It can be derived from (-1, N / 2). On the other hand, it contained in a predetermined region outside the current block (x ', y') of the prediction samples of a reference position lower sample P (N, -1) and P (-1, N / 2) weighted sum or average value of a it can be converted to the base.
[244]
For example, the prediction samples included in a predetermined regions, on the basis of the weighted sum of the reference sample, it is possible to generate a first prediction image or the second prediction image. On the other hand, prediction samples outside the predetermined regions, the reference sample average value of the minimum value or generating a first prediction image or the second prediction image to the maximum value, or by using either one of the positions defined group of reference samples first It may generate a prediction image or the second prediction image. For example, as shown in the example in shown in Figure 19, if the current block is a height of a long non-square block than the width, prediction samples of the location (x, y) included in a predetermined region within the current block, P (N / 2, see the right side derived from 1) the sample P (N / 2, y) or P (-1, y) by using either one of the left reference position of the sample may generate a first prediction image. On the other hand, prediction of the sample location that is (x ', y') is not included in the predetermined region, the P shown at right derived from the (N / 2, -1) sample P (N / 2, y ') and P ( -1, y ') it may generate a first prediction image based on a weighted sum or average of the reference sample in position.
[245]
Or, as in the example shown in Figure 20, if the current block is a long width, the non-square block than the height, the position of the prediction samples (x, y) included in a predetermined region within the current block, P (-1 , a reference derived from the lower N / 2) sample P (x, N / 2), or P (x, -1) may generate a second prediction image by using only one of the upper reference position of the sample. On the other hand, is not included in the predetermined region (x ', y') of the prediction sample position, P (-1, N / 2) sample P (x ', N / 2) derived from a lower reference, and P ( -1, y ') may generate a second prediction image based on a weighted sum or average of the reference sample in position.
[246]
In the above-described embodiment, the predetermined region or the outer region of a predetermined area, can include a residual area other than the sample located on the boundary of the current block. Boundary of the current block may include a left boundary and the right boundary, at least one of the upper boundary or lower boundary. In addition, the number or position of the boundary comprises an outer predetermined area or a predetermined area, it can be configured differently based on the type of the current block.
[247]
Under the planar mode, the final predicted image is the liquid can be guided to the first predicted image and the weighted sum, average, minimum value or based on the maximum value of the second prediction image.
[248]
For example, Equation (9), the first prediction image P h and the second prediction image P v on the basis of the weighted sum of, illustrates an example of generating a final predictive image P.
[249]
[Formula 9]

[250]
In Equation 9, the prediction weights w may now be different depending on the type of the block, the size or position of the prediction samples.
[251]
For example, the current width of the block, the height or width of the current block-can be in consideration of the height ratio, etc., lead to estimation weight w. If the current block is the width of the largest non-square block than the height, and the a w such that more weight given to the first prediction image can be set. On the other hand, there is a w such that, if the current block has a height of greater width than the non-square blocks, and the second is more weight given to the prediction image can be set.
[252]
For example, if the current block is a square, the predicted weight w may have a value of 1/2. On the other hand, the current block is a non-square block height is greater than the width (e. G., (N / 2) xN) of the case, the predicted weight w is set to 1/4, the current block is a square block width ratio is greater than the height (e. G. , if the Nx (N / 2)), predict the weight w may be set to 3/4.
[253]
[254]
When the intra-prediction mode of the current block is a directional prediction mode, the intra prediction of the current block may be performed on the basis of the directivity of the directional prediction mode. For example, Table 3, illustrates the intra prediction mode is the intra-direction parameter (intraPredAng) from Mode 2 to Mode 34 shown in FIG.
[255]
TABLE 3
predModeIntra 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
intraPredAng - 32 26 21 17 13 9 5 2 0 -2 -5 -9 -13 -17 -21
predModeIntra 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
intraPredAng -32 -26 -21 -17 -13 -9 -5 -2 0 2 5 9 13 17 21 26

[256]
Table 3, it is also possible which has been described by illustrating the 33 intra prediction modes, a greater number or a smaller number of intra prediction modes defined than than this.
[257]
Direction on the basis of the intra prediction mode, the look-up table that defines the mapping relationship between the intra-direction parameter, it is possible to determine the intra-direction parameter of the current block. Or, on the basis of information that is signaled via the bitstream, and may determine the intra-direction parameter of the current block.
[258]
Intra prediction of the current block, according to the orientation of the directional intra-prediction mode, may be performed using at least one of a left reference sample or reference sample top. Here, the top of the reference sample, reference sample (e. G., (-1, -1) from (2W-1, -1 has a smaller y-coordinate than the predicted target sample (x, 0) included in the top row within the current block )) from the mean, and the left reference sample, reference sample having a smaller x coordinate than the predicted target sample (0, y) including a current block in the leftmost column (for example, (-1, -1) (- 1, can refer to 2H-1)).
[259]
Depending on the direction of the intra-prediction mode, it is also possible to arrange the reference sample of the current block into a one-dimensional. Specifically, it is possible to select the case, these reference samples of the home, and each prediction samples to be aligned in the vertical or horizontal direction to be used for both the intra-prediction top reference sample and reference left sample when the current block .
[260]
For example, when the intra-direction parameter is a negative number (for example, in Table 3, when the intra-prediction mode that from Mode 11 corresponds to the Mode 25), the top of the reference samples and the material arranged in a horizontal or vertical direction of the left reference sample one-dimensional you can configure the reference sample group (P_ref_1D).
[261]
21 and 22 are diagrams showing the reference samples are rearranged dimensional reference sample group in a line.
[262]
Whether to re-arrange the reference samples in the vertical direction or it gets re-arranged in the horizontal direction, it can be determined according to the directional intra-prediction mode. For example, if between the intra-prediction mode index is 11 to 18, as shown in the example in shown in Figure 21, by rotating the top of the reference sample of the current block in the counterclockwise direction, the left reference samples and the top of the reference samples are vertically you can create a one-dimensional array with a reference sample group.
[263]
On the other hand, the intra-prediction mode if the between the index is 19 to 25, as shown in the example in shown in Figure 22, by rotating the left reference sample of the left reference samples of the current block in the clockwise direction, the left reference sample and reference top samples It may generate a one-dimensional reference sample group arranged in a horizontal direction.
[264]
If the intra-direction parameter of the current block is non-negative, the intra prediction of the current block may be performed using only the left reference sample or reference sample top. This makes it possible to for the intra prediction mode is the intra-direction parameter is not a negative reference sample, or using only the left upper reference sample, generating a one-dimensional reference sample group.
[265]
On the basis of the intra-direction parameter, and reference for specifying the at least one reference sample in which the prediction is used to predict the sample it can lead to the sample index determined iIdx. Further, the weight-related parameter i is used to determine the weight applied to each of the reference sample on the basis of the intra-direction parameter fact can induce. For example, Equation 10 and 11 illustrates an example of a reference sample derived decision index and a weight-related parameter.
[266]
[Equation 10]

[267]

[268]
On the basis of the determined reference sample index, it is possible to specify the at least one reference sample for each prediction samples. For example, on the basis of the determined reference sample index, it is possible to specify the position of the reference sample a reference sample group of one-dimensional prediction for predicting a current block subject sample. On the basis of the reference sample of the specified location, it is possible to generate a prediction image for the prediction sample (i.e., prediction samples).
[269]
A plurality of intra prediction modes may be used to perform intra prediction of the current block. For example, it is possible that a different intra-prediction mode or a different intra-prediction mode to be applied by each sample within the prediction current block. Alternatively, it is also possible that a different intra-prediction mode or a different intra-prediction mode to be applied by a given sample group within the current block. Here, the predetermined samples of the group, may represent a block or predetermined areas, and including the prediction samples of the sub-block, a predetermined number having a predetermined size / shape. The number of sample groups may present a variable determined according to the size / shape, the number of prediction samples contained in the current block of the block, an intra-prediction mode of the current block, have a group number of a fixed defined in the encoder and decoder may. Or, via the bit stream it is possible to signal the number of samples included in the group of the current block.
[270]
A plurality of intra-prediction mode of the current block, may be expressed by the plurality of intra-prediction mode combination. For example, the intra-prediction mode of a plurality, may be represented by a plurality of non-directional combination of the intra-prediction mode, the directional prediction mode, the non-directional intra-prediction mode of the combination or plurality of such combinations of directional intra-prediction mode. Alternatively, it is also possible to code / decode the intra-prediction mode for each unit of the different intra-prediction mode applied.
[271]
[272]
When considering the intra-prediction mode of the current block, when the prediction sample is judged to be not predictive of only one reference sample, using a plurality of reference samples, it is possible to make predictions about the prediction samples. Specifically, it can be in accordance with the intra-prediction mode of the current block, by interpolation of the reference sample and the reference neighbor to neighbor in the reference sample at a predetermined position in a predetermined sample location, performing a prediction for the prediction sample.
[273]
Be the case for example, nothing more than a virtual angle line (angular line) is one-dimensional referent peonseu sample group within the integer pel (integer pel) (i.e., the reference integer position samples) according to the inclination angle or the intra-prediction mode of intra-prediction mode , by interpolating the reference samples and the reference samples L / R or the adjacent under the / of the reference sample placed in the angle of the line, it is possible to generate a prediction image for the prediction sample. For example, Equation 11 shows an example of the interpolation of two or more reference samples, generating a prediction sample P (x, y) for the prediction sample.
[274]
[Equation 11]

[275]
Coefficient of the interpolation filter, the weight-related parameter i fact may be determined based on. For example, the coefficients of the interpolation filter can be determined based on the distance between the line angle (angular line) a small number of pel (fractional pel) and the integer pel (i.e., a constant position of each of the reference sample) in the.
[276]
When considering the intra-prediction mode of the current block, when the prediction samples are predictable only one reference sample, on the basis of reference samples which are specified by the intra-prediction mode of the current block to generate a prediction image for the prediction sample can.
[277]
For example, when passing through the virtual angle line (angular line) is a one-dimensional reference sample group within the integer pel (integer pel) (i.e., the reference integer position samples) according to the inclination angle or the intra-prediction mode of intra prediction modes, integer copy of the reference sample pel position, or, in consideration of the position between the reference sample and the prediction sample integer pel position, it is possible to generate a prediction image for the prediction sample. For example, Equation 12 by, the predicted image P (x, y) for the prediction sample to copy the block of the intra prediction mode, the reference sample P_ref_1D (x + iIdx + 1) dimensional reference sample group specified by the It shows an example of generating.
[278]
[Equation 12]

[279]
[280]
For convenience of explanation, will be in the embodiments to be described hereinafter, as the reference sample or the current block is a one-dimensional reference sample specified by the intra-prediction mode specified by the intra-prediction mode of the current block reference 1, the sample referred to. For example, according to the directional intra-prediction mode in the horizontal direction prediction image or the vertical direction can be predicted nominal wandering reference sample with reference to the first sample to be used to obtain an image, the directional intra-prediction mode of the prediction target sample in the planar mode specific a prediction reference samples of the target sample that it is possible to first designation as prediction reference samples. Further, the prediction sample is generated by predicting the prediction sample to 1 based on the reference sample comprises a first predictive image (or first predicted samples), as referred to, and the second intra prediction 1 with one reference sample intra-prediction as referred to It will be.
[281]
According to the present invention can be to increase the efficiency of intra-prediction, using the second reference samples at the predetermined position to obtain a second prediction image (or the second prediction samples) for the prediction sample. Specifically, first, by the weighted prediction a second reference sample in the first prediction image and the desired position generated by performing intra prediction result, it is possible to generate a second prediction samples for the prediction sample.
[282]
In this case, between the second is whether or not to generate the prediction samples, the current block size, shape, and intra-prediction mode (for example, a directional intra-prediction mode or not), the directional intra-prediction mode, prediction sample and a first reference sample It can be determined based on the distance. Here, the distance between the first reference sample and the prediction sample, a can be calculated based on the first reference sample and the prediction is x axis-to-axis distance between the sample and the reference sample 1, and y axis-to-axis distance between the prediction samples.
[283]
23 is a view for explaining the distance between the first reference sample and the prediction sample. In Figure 23, the distance is calculated between the first reference sample and the prediction sample the combined absolute value of the y coordinate difference between the x coordinate difference and a first reference sample and the prediction sample between the first reference sample and the prediction sample It has been illustrated as being.
[284]
For example, prediction sample and the response to the comparison with the threshold value of the distance between the first reference sample, and comparison result, may determine whether to generate a second prediction image. The threshold, (whether, for example, the directional intra-prediction mode), the width of the prediction block, the height, the intra-prediction mode or the like may be determined in a specific inclination of the intra-prediction mode.
[285]
The first can be set to a first reference sample used for intra prediction by the second reference samples. For example, the first may be set when a plurality of the reference samples in the intra-prediction is used, any one of a plurality of reference samples with a second reference sample.
[286]
Alternatively, the reference sample of the different positions and one reference sample may be set to a second reference sample. In this case, the first reference sample and the second reference sample, may be adjacent to the different boundaries of the current block, respectively, and may be adjacent to the same boundary of the current block. For example, the first reference sample and the second reference sample both may be the current block, the upper reference sample, or both the left reference samples of the current block, the one of the first reference sample and the second reference sample is the top of the reference sample, while the other may be a left reference sample.
[287]
24 and 25 are a view showing the positions of the first reference sample and the second reference samples.
[288]
Figure 24 shows a first reference sample and the example 2 reference samples adjacent to the current block will showing an example close to the same boundary, FIG 25 is a first reference sample and the second reference samples the current block is different in each boundary of the .
[289]
Specifically, in Figure 24, the first reference sample, and in the second reference sample is all been shown to be the top of the reference sample of the current block, Fig. 25, refer to the first current block sample, while the upper reference sample, the second reference sample was shown to be the left reference samples of the current block.
[290]
The second reference sample, and it can include the nearest reference samples and prediction samples. Here, the predicted and the nearest reference target sample is a sample may include at least one of the reference sample placed on the reference sample or the same vertical line lying in the same horizontal plane and the prediction sample.
[291]
This not only may determine the reference sample neighboring the first reference sample by the second reference samples.
[292]
As another example, the second reference sample, may be determined based on the direction of the intra-prediction mode of the current block. For example, the second reference sample, may be specified by the current virtual line angle (angular line) in accordance with the inclination of the intra-prediction mode of the block. For example, it is possible to set the angle of the line when extended to both sides, reference is placed at a side angle of the line samples with a first reference sample, and set with reference to the sample a second reference sample placed at the other side of the line angle.
[293]
26 is a view showing the positions of the first reference sample and the second reference samples. If it is assumed that the current block of the intra prediction mode (the Mode 34 shown in e.g., FIG. 8), the lower left diagonal direction (for example, the Mode 2 shown in FIG. 8) or the upper right diagonal directions, the intra-prediction mode from the prediction sample when the angle of the virtual line by hayeoteul extended in both, it is possible to set the reference sample placed in the position where the angle of the line passing through a first reference sample and the second reference samples. If for example, the current block of the intra prediction mode is the upper right diagonal direction, and (2, 2) for the prediction of the sample position, the reference is placed at a position of r (x + y + 2, -1), the sample is first It is determined as a reference sample, a reference sample placed at the position of r (-1, x + y + 2) can be determined by the second reference samples. On the other hand, if the current intra prediction mode is the lower left diagonal direction of the block, (2, 2) for the prediction of the sample position, the reference is placed at a position of r (-1, x + y + 2), the first reference sample is determined as a sample, a reference sample placed at the position of r (x + y + 2, -1) can be determined by the second reference samples.
[294]
Alternatively, the reference sample of the positions defined group may be set to a second reference sample. For example, it is possible to set the reference current block adjacent to the upper left corner of the sample, reference sample, such as close to the reference sample or the lower left corner is adjacent to the upper right corner to a second reference sample.
[295]
A plurality of reference sample and may be selected as the second reference samples. For example, a plurality of reference samples that meet the above criteria may be selected as the second reference sample for the second intra-prediction.
[296]
Second prediction image, the first predicted image and the weighted sum can be generated through the second reference samples. In one embodiment, Equation 13 is the second predicted image P '(x for the prediction sample (x, y) from the weighted sum of the second reference sample P_ref_2nd and the first prediction image P (x, y) of a position It shows an example of generating, y).
[297]
[Equation 13]

[298]
The understanding 1 prediction image is the liquid, because the first copy and the reference sample or interpolated to produce a plurality first reference sample, and the second prediction image would be generated by the weighted sum of the first reference sample P_ref_1st second reference sample P_ref_2nd It may be.
[299]
A first prediction image and the second reference weight to be given to the samples, respectively, based on at least one of a position of the position or the second reference sample position, the first reference samples of the size, shape, and intra-prediction mode, the prediction samples of the present block to be determined. In one embodiment, the first prediction image and the weights imparted to the second reference image, respectively, it may be determined based on the distance between the prediction sample and the first reference distance between the samples or prediction sample and the second reference samples.
[300]
For example, the distance between the prediction sample and a first reference sample as f1, and the distance between the prediction sample and the reference sample when said f2, weighted prediction parameters w is f2 / f1, f1 / f2, f2 / ( It may be set to such as f1 + f2) or f2 / (f1 + f2).
[301]
The final prediction image of the prediction sample and may be determined in the first prediction image or the second prediction image. In this case, the first whether a prediction image you want to determine whether or the second predicted image you want to determine the final prediction image to a final prediction image and the like, the current block size, shape, and can be determined depending on the position of the intra-prediction mode, prediction sample have. For example, the final prediction image by the prediction samples included in the first area within the current block is the other hand, determined by the first prediction image, a first final prediction of the prediction samples included in an area different from the first region image of the second It can be determined in a prediction image.
[302]
[303]
27 is a flowchart illustrating a process for obtaining a residual sample in one embodiment where the present invention is applied.
[304]
First, it is possible to obtain the residual coefficients of the current block (S2710). Decoder through a coefficient scanning method, it is possible to obtain the residual coefficients. For example, a decoder, a diagonal scanning, zigzag scanning and the up-light scanning, using a vertical scan or a horizontal scan, performs the scanning and counting, it is possible to obtain the residual coefficients of the resulting two-dimensional block format.
[305]
It may perform the inverse quantization to the residual coefficients of the current block (S2720).
[306]
It may determine whether to skip the inverse transformation to the inverse quantized residual coefficients of the current block (S2730). Specifically, the decoder may determine whether the horizontal or the skip (skip) the inverse transformation to at least one of the vertical direction of the current block. When it is determined to apply the inverse transform for at least one of the vertical or horizontal direction of the current block, by the inverse transform inverse quantized residual coefficients of the current block, it is possible to obtain a residual samples in the current block (S2740). Here, the inverse transformation may be performed using at least one of a DCT, DST or KLT.
[307]
If the inverse transformation is skipped for both horizontal and vertical directions of a current block, the inverse transform is not carried out at this time in the horizontal direction and vertical direction of the block. In this case, by scaling the de-quantized residual coefficients to the group set value, it is possible to obtain a residual samples in the current block (S2750).
[308]
Omitting the inverse transformation in the horizontal direction, the horizontal direction without performing an inverse transform and a vertical direction by means of performing the inverse transform. At this time, the horizontal direction may be scaled to be performed.
[309]
Omitting the inversion in the vertical direction, the vertical direction is to not perform the reverse conversion, the horizontal direction means to perform the inverse transformation. At this time, the vertical direction may be scaled to be performed.
[310]
In accordance with the split type of a current block, it may be determined whether or not whether to use the reverse skipping techniques for the current block. For example, when the current block is probably created by the division of a binary tree-based, may be restricted from using inversion techniques skipped for the current block. Accordingly, if the current block is probably created by the division of a binary tree-based, by inverse transformation of the current block, it is possible to obtain a residual samples in the current block. In addition, the encoding / decoding when the current block is probably generated by the division of a binary tree-based information (e.g., transform_skip_flag) indicating whether inversion is a skip can be omitted.
[311]
Alternatively, it is possible to limit the current block only in inversion techniques allow a skip binary tree when a base generated through the division, at least one of a horizontal direction or a vertical direction. Here, the direction in which the reverse skip techniques limit, or determined based on information decoded from the bitstream, the current block size, based on at least one of intra-prediction mode of the form or the current block of the current block may be determined adaptively have.
[312]
For example, the current block can be wide when the large non-square block than the height, allowing the inverse transform scheme skips only the vertical direction, and limits the reverse skipping techniques used for the horizontal direction. That is, if the current block 2NxN, the horizontal direction of the current block is the inverse transform is performed, is in the vertical direction can be selectively performed in the inverse transformation.
[313]
On the other hand, it may be present if the height is greater than the width of the non-square block blocks, and allows for reverse skipping technique only for the horizontal direction, and limit the use reverse skipping techniques for the vertical direction. That is, if the current block Nx2N, in the vertical direction of the current block is the inverse transform is performed, in a horizontal direction can be selectively carried out in the inverse transform.
[314]
If this example, as opposed to the current block of the one width of the largest non-square block than the height, if only reverse skip allows the techniques, the current block is a height of a large non-square block than the width in the horizontal direction, inversion only in the vertical direction It may be allowed to skip techniques.
[315]
Information indicating whether or not to skip an inversion of the information or the vertical direction on whether to skip the inverse transformation with respect to the horizontal direction can be signaled via the bitstream. In one example, the information indicating whether or not to skip a reverse conversion on the horizontal direction is a one-bit flag, 'hor_transform_skip_flag', information indicating whether or not to skip a reverse conversion on the vertical direction of the one-bit flag, 'ver_transform_skip_flag "there could be. Encoder, can be encoded in at least one of a, 'hor_transform_skip_flag' or 'ver_transform_skip_flag' according to the type of the current block. In addition, the decoder may determine whether use of the 'hor_transform_skip_flag' or 'ver_transform_skip_flag' at least, that the inverse transform in the horizontal direction or the vertical direction skipped.
[316]
In accordance with the split type of the current block, with respect to any direction, it may be set so that the inverse transform is omitted. For example, when the current block is generated by the division of a binary tree-based, may be omitted in the horizontal direction or the inverse transform in the vertical direction. That is, if the current block is generated by division of a binary tree-based, the horizontal or vertical direction with respect to the current block without encoding / decoding the current block information that indicates whether the inversion is skipped (e.g., transform_skip_flag, hor_transform_skip_flag, ver_transform_skip_flag) one may decide to skip the inverse transform for at least one.
[317]
[318]
The above-described embodiments, but is described on the basis of a series of steps or flow chart, which is not necessarily limited to a time-series order of the invention, it may be performed as needed at the same time or performed in a different order. Further, the components that make up the block diagram in the above-described embodiment (e.g., the units, modules, etc.) each of which may be implemented as a hardware device or software, as a hardware device or software in combination with a plurality of components It may be implemented. The described embodiments are implemented in the form of program instructions that may be performed through various computer components may be written in a computer-readable recording medium. The computer readable recording media may also include, alone or in combination with the program instructions, data files, data structures, and the like. Examples of the computer readable recording medium, such as hard disks, floppy disks, and magnetic tape media, CD-ROM, such as an optical recording medium, flop tikeol disk (floptical disk) such as DVD magneto-optical medium (magneto-optical storing program instructions, such as media), and ROM, RAM, flash memory, hardware devices that are specially configured to, perform. The hardware devices may be configured to act as one or more software modules in order to perform the process according to the invention, and vice versa.
Industrial Applicability
[319]
The present invention can be applied to electronic devices capable of encoding / decoding an image.

Claims
[Claim 1]
Determining an intra prediction mode of the current block; Determining, based on the intraprediction mode, determining a first reference samples of the prediction samples contained in the current block; Comprising: using the first reference sample, generating a first prediction samples for the prediction sample; And the first prediction sample and using the second reference samples of different positions and wherein the first reference sample, and the second comprising the step of generating the predicted sample, the image decoding method for the prediction sample.
[Claim 2]
The method of claim 1, wherein the second reference sample is, the image decoding method comprising at least one of the prediction reference placed on the same vertical line with the reference samples or the prediction sample is placed in the same horizontal plane with the target sample sample.
[Claim 3]
The method of claim 1, wherein the first reference sample and the second reference samples, each of the above, the image decoding method characterized in that the current close to the different boundaries of the block.
[Claim 4]
The method of claim 3, wherein the position of the second reference sample is, the image decoding method, characterized in that is determined based on the direction of the intra-prediction mode.
[Claim 5]
The method of claim 1, wherein the second prediction samples, the first sample and the prediction, the video decoding method of being generated based on the weighted sum of the second reference samples.
[Claim 6]
The method of claim 5 wherein at least one of the first prediction sample and the second reference sample weight applied to each of the predicting target position of the sample, wherein the position of the first reference sample and the position of the second reference sample , image decoding method, characterized in that is determined based.
[Claim 7]
The method of claim 1, wherein the second whether or not to generate the prediction samples is, the image decoding method characterized in that based on the direction of the intra-prediction mode.
[Claim 8]
Determining an intra prediction mode of the current block; Determining, based on the intraprediction mode, determining a first reference samples of the prediction samples contained in the current block; Comprising: using the first reference sample, generating a first prediction samples for the prediction sample; And the first prediction sample and using the second reference samples of different positions and wherein the first reference sample, and the second comprising the step of generating the predicted sample, the image encoding method for the prediction sample.
[Claim 9]
The method of claim 8, wherein the second reference sample is, the image encoding method comprising at least one of the prediction reference placed on the same vertical line with the reference samples or the prediction sample is placed in the same horizontal plane with the target sample sample.
[Claim 10]
The method of claim 8, wherein the first reference sample and the second reference samples, each of said current, characterized in that adjacent to the different boundaries of the block, the image encoding method.
[Claim 11]
11. The method of claim 10, wherein the position of the second reference sample is, the image encoding method, characterized in that is determined based on the direction of the intra-prediction mode.
[Claim 12]
The method of claim 8, wherein the second prediction samples, the first sample and the prediction, the image encoding method, characterized in that is generated based on the weighted sum of the second reference samples.
[Claim 13]
13. The method of claim 12, wherein at least one of the first prediction sample and the second reference sample weight applied to each of the predicting target position of the sample, wherein the position of the first reference sample and the position of the second reference sample , the image encoding method, characterized in that is determined based.
[Claim 14]
The method of claim 8, wherein the second whether or not to generate the prediction samples is, the image encoding method, characterized in that determined in accordance with the direction of the intra-prediction mode.
[Claim 15]
Using the first reference sample to determine the intra-prediction mode of the current block, based on the intra-prediction mode, and determines the first reference samples of the prediction samples contained in the current block, the prediction sample generating a first prediction samples, wherein the first prediction sample and using the second reference samples of different positions and wherein the first reference sample, including the intra-prediction unit generating a second prediction samples for the prediction sample the image decoding apparatus.