The present disclosure relates to an image encoding device and method and an image decoding device and method, and more particularly, to an image encoding device and method and an image decoding device and method, which are capable of suppressing an increase in encoding or decoding workload.
Background Art
Recently, devices for compressing and encoding an image by adopting a encoding scheme of handling image information digitally and performing compression by an orthogonal transform such as a discrete cosine transform and motion compensation using image information-specific redundancy for the purpose of information transmission and accumulation with high efficiency when the image information is handled digitally have become widespread. Moving Picture Experts Group (MPEG) and the like are examples of such encoding schemes. [0003]
Particularly, MPEG 2 (ISO/IEC 13818-2) is a standard that is defined as a gen era [-purpose image encoding scheme, and covers interlaced scan images, progressive scan images, standard resolution images, and high definition images. For example, MPEG 2 is now being widely used in a wide range of applications such as professional use and consumer use. Using the MPEG 2 compression scheme, for example, in the case of an interlaced scan image of a standard resolution having 720x480 pixels, a coding amount (bit rate) of 4 to 8 Mbps is allocated. Further, using the MPEG 2 compression scheme, for example, in the case of an interlaced

scan image of a high resolution having 1920*1088 pixels, a coding amount (bit rate)
of 18 to 22 Mbps is allocated. Thus, it is possible to implement a high compression
rate and a preferable image quality.
[0004]
5 MPEG 2 is mainly intended for high definition coding suitable for
broadcasting but does not support an encoding scheme having a coding amount (bit
rate) lower than that of MPEG 1, that is, an encoding scheme of a high compression
rate. With the spread of mobile terminals, it is considered that the need for such an
encoding scheme will increase in the future, and thus an MPEG 4 encoding scheme 10 has been standardized. An international standard for an image encoding scheme
was approved as 1SO/1EC 14496-2 in December, 1998.
[0005]
Further, in recent years, standards such as H.26L (International
Telecommunication Union Telecommunication Standardization Sector Q6/I6 Video 15 Coding Expert Group (ITU-T Q6/16 VCEG)) for the purpose of image encoding for
video conferences have been standardized. H.26L requires a larger computation
amount for encoding and decoding than in existing encoding schemes such as MPEG
2 or MPEG 4, but is known to implement high encoding efficiency. Further,
currently, as one activity of MPEG 4, standardization of incorporating even a 20 function that is not supported in H.26L and implementing high encoding efficiency
based on H.26L has been performed as a Joint Model of Enhanced-Compression
Video Coding.
[0006]
As a standardization schedule, an international standard called H.264 and 25 MPEG-4 Parti0 (Advanced Video Coding (hereinafter referred to as "AVC") was
established in March, 2003.
[0007]
Furthermore, as an extension of H.264/AVC, Fidelity Range Extension
(FRExt) including an encoding tool necessary for professional use such as RGB or 30 4:2:2 or 4:4:4 or 8><8 DCT and a quantization matrix which are specified in MPEG-2
was standardized in February, 2005. As a result, H.264/AVC has become an
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encoding scheme capable of also expressing film noise included in movies well and is being used in a wide range of applications such as Blu-Ray Discs (trademark). [0008]
However, in recent years, there is an increasing need for high compression 5 rate encoding capable of compressing an image of about 4000x2000 pixels, which is 4 times that of a high-definition image, or delivering a high-definition image in a limited transmission capacity environment such as the Internet. To this end, improvements in encoding efficiency have been under continuous review by Video Coding Experts Group (VCEG) under ITU-T.
10 [0009]
In this regard, currently, in order to further improve the encoding efficiency to be higher than in AVC, Joint Collaboration Team-Video Coding (JCTVC), which is a joint standardization organization of ITU-T and ISO/IEC, has been standardizing an encoding scheme called High Efficiency Video Coding (HEVC). A committee
15 draft that is a draft specification for the HEVC standard was issued in January, 2013 (see Non-Patent Literature 1). [0010]
In HEVC, it is possible to perform parallel processing based on a tile or wavefront parallel processing in addition to a slice that is also defined in AVC.
20 [0011]
Moreover, the existing image encoding schemes such as MPEG-2 and AVC have a scalability function of dividing an image into a plurality of layers and encoding the plurality of layers. [0012]
25 111 other words, for example, for a terminal having a low processing
capability such as a mobile phone, image compression information of only a base layer is transmitted, and a moving image of low spatial and temporal resolutions or a low quality is reproduced, and for a terminal having a high processing capability such as a television or a personal computer, image compression information of an
30 enhancement layer as well as a base layer is transmitted, and a moving image of high spatial and temporal resolutions or a high quality is reproduced. That is, image

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compression information according to a capability of a terminal or a network can be transmitted from a server without performing the transcoding process.
Citation List 5 Non-Patent Literature [0013]
Non-Patent Literature I: Benjamin Brass, Woo-Jin Han, Gary J. Sullivan, Jens-Rainer Ohm, Gary J. Sullivan, Ye-Kui Wang, Thomas Wiegand, "High Efficiency Video Coding (HEVC) text specification draft 10 (for FDIS & Consent)," 10 JCTVC-LI003__v4, Joint Collaborative Team on Video Coding (JCT-VC) of ITU-T SG 16 WP 3 and 1SO/1EC JTC 1/SC 29/WG 11 12th Meeting: Geneva, CH, 14-23 Jan. 2013
Summary of Invention 15 Technical Problem [0014]
However, in the method of the related ait, when encoding-related information of the base layer such as decoded image information or the motion information is referred to in encoding and decoding of the enhancement layer, the 20 entire picture of the base layer was a target for reference. [0015]
For this reason, workload was likely to increase, for example, in encoding and decoding of the enhancement layer, the number of memory accesses for referring to the encoding-related information of the base layer increases. 25 [0016]
The present disclosure has been made in light of the foregoing, and it is desirable to suppress an increase in encoding or decoding workload.
Solution to Problem 30 [0017]
According to an embodiment of the present technology, there is provided an
image encoding device including: a generation section configured to generate control information used to control a certain area in which encoding-related information, of another layer encoded for each of a plurality of certain areas obtained by dividing a picture, is referred to regarding a current layer of image data including a plurality 5 of layers; an encoding section configured to encode the current layer of the image data with reference to the encoding-related information of some areas of the other layer according to control of the control information generated by the generation section; and a transmission section configured to transmit encoded data of the image data generated by the encoding section and the control information generated by the
10 generation section. [0018]
The control information may be information limiting an area in which the encoding-related information is referred to by designating an area in which reference to the encoding-related information of the other layer is permitted, designating an
15 area in which reference to the encoding-related information is prohibited, or designating an area in which the encoding-related information is referred to. [0019]
The control information may designate the area using an identification number allocated in a raster scan order, information indicating positions of the area
20 in vertical and horizontal directions in a picture, or information indicating a data position of the area in the encoded data. [0020]
The transmission section may further transmit information indicating whether or not to control an area in which the encoding-related information is
25 referred to. [0021]
The encoding-related information may be information used for generation of a prediction image used in encoding of the image data. [0022]
30 The information used for the generation of the prediction image may include
information used for texture prediction of the image data and information used for

syntax prediction of the image data. The control information may be information used to independently control an area in which the information used for the texture prediction is referred to and an area in which the information used for the syntax prediction is referred to. 5 [0023]
The generation section may generate the control information for each of the plurality of certain areas obtained by dividing the picture of the current layer of the image data. The encoding section may encode the current layer of the image data with reference to the encoding-related information of some areas of the other layer 10 for each of the areas according to control of the control information of each area generated by the generation section. [0024]
The transmission section may further transmit information indicating whether or not an area division of the current layer is similar to an area division of 15 the other layer. [0025]
The area may be a slice or a tile of the image data. [0026]
According to an embodiment of the present technology, there is provided an 20 image encoding method including: generating control information used to control a certain area in which encoding-related information, of another layer encoded for each of a plurality of certain areas obtained by dividing a picture, is referred to regarding a current layer of image data including a plurality of layers; encoding the current layer of the image data with reference to the encoding-related information of some 25 areas of the other layer according to control of the generated control information; and transmitting encoded data generated by encoding the image data and the generated control information. [0027]
According to another embodiment of the present technology, there is
30 provided an image decoding device including: a reception section configured to
receive encoded data of a current layer of image data including a plurality of layers

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and control information used to control a certain area in which encoding-related information, of another layer encoded for each of a plurality of certain areas obtained by dividing a picture of the image data, is referred to; and a decoding section configured to decode the encoded data with reference to the encoding-related 5 information of some areas of the other layer according to control of the control information received by the reception section. [0028]
The control information may be information limiting an area in which the encoding-related information is referred to by designating an area in which reference
10 to the encoding-related information of the other layer is permitted, designating an area in which reference to the encoding-related information is prohibited, or designating an area in which the encoding-related information is referred to. [0029]
The control information may designate the area using an identification
15 number allocated in a raster scan order, information indicating positions of the area in vertical and horizontal directions in a picture, or information indicating a data position of the area in the encoded data. [0030]
The reception section may further receive information indicating whether or
20 not to control an area in which the encoding-related information is referred to. [0031]
The encoding-related information may be information used for generation of a prediction image used in decoding of the encoded data. [0032]
25 The information used for the generation of the prediction image may include
information used for texture prediction of the image data and information used for syntax prediction of the image data. The control information may be information used to independently control an area in which the information used for the texture prediction is referred to and an area in which the information used for the syntax
30 prediction is referred to. [0033]

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The reception section may receive the encoded data encoded for each of the plurality of certain areas obtained by dividing the picture of the current layer of the image data and the control information of each of the areas. The decoding section may decode the encoded data received by the reception section with reference to the 5 encoding-related information of some areas of the other layer for each of the areas according to control of the control information of each area. [0034]
The reception section may further receive information indicating whether or not an area division of the current layer is similar to an area division of the other 10 layer. [0035]
The area may be a slice or a tile of the image data. [0036]
According to another embodiment of the present technology, there is 15 provided an image decoding method including: receiving encoded data of a current layer of image data including a plurality of layers and control information used to control a certain area in which encoding-related information, of another layer encoded for each of a plurality of certain areas obtained by dividing a picture of the image data, is referred to; and decoding the encoded data with reference to the 20 encoding-related information of some areas of the other layer according to control of the received control information. [0037]
According to one aspect of the present technology, control information used to control an area in which encoding-related information, of another layer encoded •25 for each of a plurality of certain areas obtained by dividing a picture, is referred to regarding a current layer of image data including a plurality of layers is generated, the current layer of the image data is encoded with reference to the encoding-related information of some areas of the other layer according to control of the generated control information, and encoded data generated by encoding the image data and the 30 generated control information is transmitted. [0038]

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According to another aspect of the present technology, encoded data of a cuirent layer of image data including a plurality of layers and control information used to control an area in which encoding-related information, of another layer encoded for each of a plurality of certain areas obtained by dividing a picture of the 5 image data, is refeired to are received, and the encoded data is decoded with reference to the encoding-related information of some areas of the other layer according to control of the received control information.
Advantageous Benefits of Invention 10 [0039]
According to the present disclosure, it is possible to encode and decode an image. Particularly, it is possible to suppress an increase in encoding or decoding workload.
15 Brief Description of Drawings
[0040]
[FIG. 1] FIG. 1 is a diagram for describing an example of a configuration of a coding
unit.
[FIG. 2] FIG. 2 is a diagram illustrating an example of a scalable layered image 20 encoding scheme.
[FIG. 3] FIG. 3 is a diagram for describing an example of spatial scalable coding.
[FIG. 4] FIG. 4 is a diagram for describing an example of temporal scalable coding.
[FIG. 5] FIG. 5 is a diagram for describing an example of scalable coding of a signal
to noise ratio. 25 [FIG. 6] FIG. 6 is a diagram for describing an example of a slice.
[FIG. 7] FIG. 7 is a diagram for describing an example of a tile.
[FIG. 8] FIG. 8 is a diagram for describing an example of base layer reference control.
[FIG. 9] FIG. 9 is a diagram for describing an example of a tile setting.
[FIG. 10] FIG. 10 is a diagram for describing another example of base layer reference 30 control.
[FIG. 11] FIG. ! 1 is a diagram for describing an example of a parallel process.

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[FIG. 12] FIG. 12 is a diagram for describing an example of a method of allocating an
identification number of a tile.
[FIG. 13] FIG. 13 is a diagram for describing an example of syntax of a picture
parameter set. 5 [FIG. 14] FIG. 14 is a continuation from FIG. 13 for describing an example of syntax
of a picture parameter set.
[FIG. 15] FIG. 15 is a diagram for describing an example of syntax of a slice header.
[FIG. 16] FIG. 16 is a continuation from FIG. 15 for describing an example of syntax
of a slice header. 10 [FIG. 17] FIG. 17 is a continuation from FIG. 16 for describing an example of syntax
of a slice header.
[FIG. 18] FIG. 18 is a block diagram illustrating an example of a main configuration
of an image encoding device.
[FIG. 19] FIG. 19 is a block diagram illustrating an example of a main configuration 15 of a base layer image encoding section.
[FIG. 20] FIG. 20 is a block diagram illustrating an example of a main configuration
of an enhancement layer image encoding section.
[FIG. 21] FIG. 21 is a block diagram illustrating an example of a main configuration
of an area synchronization section. 20 [FIG. 22] FIG. 22 is a flovvchait for describing an example of the flow of an image
encoding process.
[FIG. 23] FIG. 23 is a flowchart for describing an example of the flow of a base layer
encoding process.
[FIG. 24] FIG. 24 is a flowchart for describing an example of the flow of an 25 enhancement layer encoding process.
[FIG. 25] FIG. 25 is a flowchart for describing an example of the flow of an
enhancement layer encoding process, continuing from FIG. 24.
[FIG. 26] FIG. 26 is a block diagram illustrating an example of a main configuration
of an image decoding device. 30 [FIG. 27] FIG. 27 is a block diagram illustrating an example of a main configuration
of a base layer image decoding section.

I
1

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[FIG 28] FIG 28 is a block diagram illustrating an example of a main configuration
of an enhancement layer image decoding section.
[FIG 29] FIG 29 is a block diagram illustrating an example of a main configuration
of an area synchronization section. 5 [FIG 30] FIG 30 is a flowchart for describing an example of the flow of an image
decoding process.
[FIG. 31] FIG. 31 is a flowchart for describing an example of the flow of a base layer
decoding process.
[FIG. 32] FIG. 32 is a flowchart for describing an example of the flow of an 10 enhancement layer decoding process.
[FIG. 33] FIG. 33 is a flowchart for describing an example of the flow of an
enhancement layer decoding process, continuing from FIG. 32.
[FIG. 34] FIG. 34 is a diagram illustrating an example of a multi-view image
encoding scheme. 15 [FIG. 35] FIG. 35 is a diagram illustrating an example of a main configuration of a
multi-view image encoding device to which the present disclosure is applied.
[FIG. 36] FIG. 36 is a diagram illustrating an example of a main configuration of a
multi-view image decoding device to which the present disclosure is applied.
[FIG. 37] FIG. 37 is a block diagram illustrating an example of a main configuration 20 of a computer.
[FIG. 38] FIG. 38 is a block diagram illustrating an example of a schematic
configuration of a television device.
[FIG. 39] FIG. 39 is a block diagram illustrating an example of a schematic
configuration of a mobile phone. 25 [FIG. 40] FIG 40 is a block diagram illustrating an example of a schematic
configuration of a recording/reproduction device.
[FIG. 41] FIG. 41 is a block diagram illustrating an example of a schematic
configuration of an image capturing device.
[FIG. 42] FIG. 42 is a block diagram illustrating an example of using scalable coding. 30 [FIG. 43] FIG. 43 is a block diagram illustrating another example of using scalable
coding.

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[FIG. 44] FIG. 44 is a block diagram illustrating another example of using scalable
coding.
[FIG. 45] FIG. 45 is a block diagram illustrating an example of a schematic
configuration of a video set. 5 [FIG. 46] FIG. 46 is a block diagram illustrating an example of a schematic
configuration of a video processor.
[FIG. 47] FIG. 47 is a block diagram illustrating another example of a schematic
configuration of a video processor.
[FIG. 48] FIG. 48 is an explanatory diagram illustrating a configuration of a content 10 reproducing system.
[FIG. 49] FIG. 49 is an explanatory diagram illustrating the flow of data in a content
reproducing system.
[FIG. 50] FIG. 50 is an explanatory diagram illustrating a specific example of an
MPD. 15 [FIG. 51] FIG. 51 is a functional block diagram illustrating a configuration of a
content server of a content reproducing system.
[FIG. 52] FIG. 52 is a functional block diagram illustrating a configuration of a
content reproducing device of a content reproducing system.
[FIG. 53] FIG. 53 is a functional block diagram illustrating a configuration of a 20 content server of a content reproducing system.
[FIG. 54] FIG. 54 is a sequence chart illustrating a communication processing
example by respective devices of a wireless communication system.
[FIG. 55] FIG. 55 is a sequence chart illustrating a communication processing
example by respective devices of a wireless communication system. 25 [FIG. 56] FIG. 56 is a diagram schematically illustrating an example of a
configuration of a frame format transmitted and received in a communication process
by respective devices of a wireless communication system.
[FIG. 57] FIG. 57 is a sequence chart illustrating a communication processing
example by respective devices of a wireless communication system. 30
Description of Embodiments

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[0041]
Hereinafter, modes (hereinafter, referred to as "embodiments") for carrying
out the present disclosure will be described. A description will proceed in the
following order.
5 1. Main description of present technology
2. First embodiment (image encoding device)
3. Second embodiment (image decoding device)
4. Third embodiment (multi-view image encoding device and multi-view image decoding device)
10 5. Fourth embodiment (computer)
6. Application examples
7. Application examples of scalable coding
8. Fifth embodiment (set, unit, module, and processor)
9. Application example of content reproducing system of MPEG-DASH
15 10. Application example of wireless communication system of Wi-Fi
standard [0042]
<1. Main Description for Present Technology>
< Overview>
20 [Encoding scheme]
Hereinafter, the present technology will be described in connection with an
application to image encoding and decoding of a High Efficiency Video Coding
(HEVC) scheme.
[0043]
25
In an Advanced Video Coding (AVC) scheme, a hierarchical structure based on a macroblock and a sub macroblock is defined. However, a macroblock of 16x16 pixels is not optimal for a large image frame such as a Ultra High Definition (UHD) (4000x2000 pixels) serving as a target of a next generation encoding scheme. 30 [0044]
On the other hand, in the HEVC scheme, a coding unit (CU) is defined as

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illustrated in FIG. 1. [0045]
A CU is also referred to as a coding tree block (CTB), and serves as a partial area of an image of a picture unit undertaking a similar role of a macroblock in the 5 AVC scheme. The latter is fixed to a size of 16x16 pixels, but the former is not fixed to a certain size but designated in image compression information in each sequence. [0046]
For example, a largest coding unit (LCU) and a smallest coding unit (SCU) 10 of a CU are specified in a sequence parameter set (SPS) included in encoded data to be output. [0047]
As split-flag=l is set in a range in which each LCU is not smaller than an SCU, a coding unit can be divided into CUs having a smaller size. In the example 15 of FIG. I, a size of an LCU is 128, and a largest scalable depth is 5. A CU of a size of 2Nx2N is divided into CUs having a size of N*N serving as a layer that is one-level lower when a value of split flag is 1. [0048]
Further, a CU is divided in prediction units (PUs) that are areas (partial 20 areas of an image of a picture unit) serving as processing units of intra or inter prediction, and divided into transform units (TUs) that are areas (partial areas of an image of a picture unit) serving as processing units of orthogonal transform. Currently, in theHEVC scheme, in addition to 4><4 and 8*8, orthogonal transform of 16x16 and 32x32 can be used. 25 [0049]
As in the HEVC scheme, in the case of an encoding scheme in which a CU is defined and various kinds of processes are performed in units of CUs, in the AVC scheme, a macroblock can be considered to correspond to an LCU, and a block (sub block) can be considered to correspond to a CU. Further, in the AVC scheme, a 30 motion compensation block can be considered to correspond to a PU. However, since a CU has a hierarchical structure, a size of an LCU of a topmost layer is

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commonly set to be larger than a macroblock in the AVC scheme, for example, such
as 128x128 pixels.
[0050]
Thus, hereinafter, an LCU is assumed to include a macroblock in the AVC 5 scheme, and a CU is assumed to include a block (sub block) in the AVC scheme. Tn other words, a "block" used in the following description indicates an arbitrary partial area in a picture, and, for example, a size, a shape, and characteristics thereof are not limited. Tn other words, a "block" includes an arbitrary area (a processing unit) such as a TU, a PU, an SCU, a CU, an LCU, a sub block, a macroblock, or a slice. 10 Of course, a "block" includes other partial areas (processing units) as well. When it is necessary to limit a size, a processing unit, or the like, it wilT be appropriately described. [0051]

15 Moreover, in the AVC and HEVC encoding schemes, in order to achieve
high encoding efficiency, it is important to select an appropriate prediction mode. [0052]
As an example of such a selection method, there is a method implemented in reference software (found at http://iphome.hhi.de/suehring/tml/index.htm) of 20 H.264/MPEG-4 AVC called a joint model (JM). [0053]
Tn the JM, as will be described later, it is possible to select two mode determination methods, that is, a high complexity mode and a low complexity mode. Tn both modes, cost function values related to respective prediction modes are 25 calculated, and a prediction mode having a smaller cost function value is selected as an optimal mode for a corresponding block or macroblock. [0054]
A cost function in the high complexity mode is represented as in the following Formula (1): 30 [0055] [Math. 1]

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Cost(ModeeQ)=D+A*R ■ ■ -(1)
[0056]
Here, Q indicates a universal set of candidate modes for encoding a corresponding block or macroblock, and D indicates differential energy between a 5 decoded image and an input image when encoding is performed in a corresponding prediction mode. X indicates Lagrange's undetermined multiplier given as a function of a quantization parameter. R indicates a total coding amount including an orthogonal transform coefficient when encoding is peifonned in a corresponding mode. 10 [0057]
In other words, in order to perform encoding in the high complexity mode, it is necessary to perform a temporary encoding process once by all candidate modes in order to calculate the parameters D and R, and thus a large computation amount is required. 15 [0058]
A cost function in the low complexity mode is represented by the following Formula (2): [0059] [Math. 2]
2o Cost (Mode eQ)=D+QP2Quant(QP) * HeaderBit ■ ■ -(2)
[0060]
Here, D is different from that of the high complexity mode and indicates
differential energy between a prediction image and an input image. QP2Quant (QP)
is given as a function of a quantization parameter QP, and HeaderBit indicates a 25 coding amount related to information belonging to a header such as a motion vector
or a mode including no orthogonal transform coefficient.
[0061]
In other words, in the low complexity mode, it is necessary to perform a
prediction process for respective candidate modes, but since a decoded image is not 30 necessary, it is unnecessary to perforin an encoding process. Thus, it is possible to
implement a computation amount smaller than that in the high complexity mode.

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[0062]

Moreover, the existing image encoding schemes such as MPEG2 and AVC have a scalability function. Scalable coding refers to a scheme of dividing 5 (hierarchizing) an image into a plurality of layers and performing encoding for each layer. FJG. 2 is a diagram illustrating an example of a layered image encoding scheme. [0063]
As illustrated in FIG. 2, in hierarchization of an image, one image is divided
10 into a plurality of layers based on a certain parameter with a scalability function. In other words, a hierarchized image (a layered image) includes a plurality of layers that differs in a value of a certain parameter. The plurality of layers of the layered image is configured with a base layer on which encoding and decoding are perfomied using only an image of its own layer without using an image of another
15 layer and a non-base layer (which is also referred to as an "enhancement layer") on which encoding and decoding are perfomied using an image of another layer. For the non-base layer, an image of the base layer may be used, and an image of another non-base layer may be used. [0064]
20 Generally, in order to reduce the redundancy, the non-base layer is
configured with data (differential data) of a differential image between an image of its own and an image of another layer. For example, when one image is hierarchized into two layers, that is, the base layer and the non-base layer (also referred to as an "enhancement layer"), an image of a lower quality than an original
25 image is obtained using only data of the base layer, and an original image (that is, a high-quality image) is obtained by combining data of the base layer with data of the enhancement layer. [0065]
As an image is hierarchized as described above, it is possible to obtain
30 images of various qualities according to the situation. For example, for a terminal having a low processing capability such as a mobile phone, image compression

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information of only a base layer is transmitted, and a moving image of low spatial and temporal resolutions or a low quality is reproduced, and for a terminal having a high processing capability such as a television or a personal computer, image compression information of an enhancement layer as well as a base layer is 5 transmitted, and a moving image of high spatial and temporal resolutions or a high quality is reproduced. In other words, image compression information according to a capability of a terminal or a network can be transmitted from a server without performing the transcoding process. [0066]
10
In such layered image encoding and layered image decoding (scalable encoding and scalable decoding), a parameter with a scalability function is arbitrary. For example, spatial resolution as illustrated in FIG. 3 may be its parameter (spatial scalability). When the spatial scalability differs, respective layers have different
15 resolutions of an image. In other words, each picture is hierarchized into two layers, that is, a base layer of a resolution spatially lower than that of an original image and an enhancement layer that is combined with an image of the base layer to obtain an original image (an original spatial resolution) as illustrated in FIG. 3. Of course, the number of layers is an example, and each picture can be hierarchized into an
20 arbitrary number of layers. [0067]
As another parameter having such scalability, for example, a temporal resolution (temporal scalability) as illustrated in FIG. 4 may be applied. In the case of the temporal scalability, respective layers have different frame rates. In other
25 words, in this case, each picture is hierarchized into layers having different frame rates, a moving image of a high frame rate can be obtained by combining a layer of a high frame rate with a layer of a low frame rate, and an original moving image (an original frame rate) can be obtained by combining all the layers as illustrated in FIG. 4. The number of layers is an example, and each picture can be hierarchized into an
30 arbitrary number of layers. [0068]

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Further, as another parameter having such scalability, for example, there is a signal-to-noise ratio (SNR) (SNR scalability). In the case of the SNR scalability, respective layers having different SNRs. In other words, in this case, each picture is hierarchized into two layers, that is, a base layer of an SNR lower than that of an 5 original image and an enhancement layer that is combined with an image of the base layer to obtain an original SNR as illustrated in FIG. 5. In other words, for base layer image compression information, information related to an image of a low PSNR is transmitted, and a high PSNR image can be reconstructed by combining the information with the enhancement layer image compression information. Of course, 10 the number of layers is an example, and each picture can be hierarchized into an arbitrary number of layers. [0069]
A parameter other than the above-described examples may be applied as a parameter having scalability. For example, there is bit-depth scal

Claim I
An image encoding device comprising:
a generation section configured to generate control information used to 5 control a certain area in which encoding-related information, of another layer encoded for each of a plurality of certain areas obtained by dividing a picture, is referred to regarding a current layer of image data including a plurality of layers;
an encoding section configured to encode the current layer of the image data with reference to the encoding-related information of some areas of the other layer 10 according to control of the control information generated by the generation section; and
a transmission section configured to transmit encoded data of the image data
generated by the encoding section and the control information generated by the
generation section.
Claim 2 (currently amended)
The image encoding device accordingto claim 1,
wherein the control information designates an area in which reference to the encoding-related information of the other layer is permitted. 20
Claim 3 (currently amended)
The image encoding device accordingto claim 1,
wherein, the control information designates an area in which reference to the encoding-related information of the other layer is prohibited. 25
Claim 4 (currently amended)
The image encoding device according to claim 1,
wherein the control information designates an area in which the encoding-related information of the other layer is referred to.
Claim 5 (currently amended)

The image encoding device according to any of claims 2 to 4, wherein the control information designates the area using an identification number allocated in a raster scan order.
Claim 6 (currently amended)
The image encoding device according to any of claims 2 to 4, wherein the control information designates the area using information indicating a position of the area in a picture.
Claim 7 (currently amended)
The image encoding device according to claim 1,
wherein the generation section further generates infonnation indicating whether or not an area division of the current layer is similar to an area division of the other layer. 15
Claim 8 (currently amended)
The image encoding device according to claim 1,
wherein the generation section generates control information determination information serving as information used to control whether or not control 20 information is transmitted, and generate the control information based on the control information determination information.
Claim 9 (currently amended)
The image encoding device according to claim 1,
wherein the transmission section further transmits information indicating
whether or not to control an area in which the encoding-related information is referred to.
Claim 10 (currently amended)
The image encoding device according to claim 1,
wherein the encoding-related information is information used for generation
of a prediction image used in encoding of the image data.
Claim 11 (currently amended)
The image encoding device according to claim 10,
wherein the information used for the generation of the prediction image
includes information used for texture prediction of the image data and information used for syntax prediction of the image data, and
the control information is iiifomiation used to independently control an area in which the information used for the texture prediction is refeired to and an area in 10 which the information used for the syntax prediction is referred to.
Claim 12 (currently amended)
The image encoding device, according to claim 1,
wherein the generation section generates the control information for each of the plurality of certain areas obtained by dividing the picture of the current layer of the image data, and
the encoding section encodes the current layer of the image data with reference to the encoding-related information of some areas of the other layer for each of the areas according to control of the control information of each area generated by the generation section.
Claim 13 (currently amended)
The image encoding device according to claim 1, wherein the area is a slice or a tile of the image data.
Claim 14 (currently amended)
An image encoding method comprising:
generating control information used to control a certain area in which encoding-related information, of another layer encoded for each of a plurality of 30 certain areas obtained by dividing a picture, is referred to regarding a current layer of image data including a plurality of layers;
encoding the current layer of the image data with reference to the encoding-related information of some areas of the other layer according to control of the generated control information; and
transmitting encoded data generated by encoding the image data and the 5 generated control information.
Claim 15 (currently amended)
An image decoding device comprising:
a reception section configured to receive encoded data of a cuirent layer of
image data including a plurality of layers and control infonnation used to control a
certain area in which encoding-related infonnation, of another layer encoded for each
of a plurality of certain areas obtained by dividing a picture of the image data, is
referred to; and
a decoding section configured to decode the encoded data with reference to 15 the encoding-related information of some areas of the other layer according to control of the control infonnation received by the reception section.
Claim 16 (currently amended)
The image decoding device according to claim 15,
wherein the control information designates an area in which reference to the
encoding-related infonnation of the other layer is permitted.
Claim 17 (currently amended)
The image decoding device according to claim 15,
wherein the control information designates an area in which reference to the
encoding-related information of the other layer is prohibited.
Claim 18 (currently amended)
The image decoding device according to claim 15,
wherein the control information designates an area in which the encoding-
related information of the other layer is referred to.

Claim 19 (currently amended)
The image decoding device according to any of claims 16 to 18, wherein the control information designates the area using an identification number allocated in a raster scan order.
Claim 20 (currently amended)
The image decoding device according to any of claims 16 to 18, wherein the control information designates the area using infonnation 10 indicating a position of the area in a picture.
Claim 21 (new)
The image decoding device according to claim 15,
wherein the reception section further receives information indicating 15 whether or not an area division of the current layer is similar to an area division of the other layer.
Claim 22 (new)
The image decoding device according to claim 15,
wherein the reception section receives control information determination
information serving as information used to control whether or not control information is transmitted, and receives the control information based on the control information determination information.
Claim 23 (new)
The image decoding device according to claim 15,
wherein the reception section further receives information indicating whether or not to control an area in which the encoding-related information is referred to.
Claim 24 (new)
The image decoding device according to claim 15,
wherein the encoding-related information is information used for generation of a prediction image used in decoding of the image data.
Claim 25 (new)
The image decoding device according to claim 24,
wherein the information used for the generation of the prediction image
includes information used for texture prediction of the image data and information
used for syntax prediction of the image data, and
the control information is information used to independently control an area
in which the information used for the texture prediction is referred to and an area in which the information used for the syntax prediction is referred to.
Claim 26 (new)
The image decoding device according to claim 15,
wherein the reception section receives the encoded data encoded for each of the plurality of certain areas obtained by dividing the picture of the current layer of the image data and the control information of each of the areas, and
the decoding section decodes the encoded data received by the reception 20 section with reference to the encoding-related information of some areas of the other layer for each of the areas according to control of the control information of each area.
Claim 27 (new)
The image decoding device according to claim 15,
wherein the area is a slice or a tile of the image data.
Claim 28 (new)
An image decoding method comprising:
receiving encoded data of a current layer of image data including a plurality
of layers and control information used to control a certain area in which encoding-
related information, of another layei; encoded for each of a plurality of certain areas obtained by dividing a picture of the image data, is referred to; and
decoding the encoded data with reference to the encoding-related information of some areas of the other layer according to control of the received control information.