DESC:FORM 2

THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENT RULES, 2003

COMPLETE SPECIFICATION
(See Section 10 and Rule 13)

Title of invention:
METHOD AND SYSTEM FOR GROUND TRUTH DETERMINATION IN LANE DEPARTURE WARNING

Applicant:
Tata Consultancy Services Limited
A company Incorporated in India under The Companies Act, 1956
Having address:
Nirmal Building, 9th Floor,
Nariman Point, Mumbai 400021,
Maharashtra, India

The following specification particularly describes the invention and the manner in which it is to be performed.

CROSS-REFERENCE TO RELATED APPLICATIONS AND PRIORITY
[001] The present application claims priority to Indian Provisional Patent Application No. 1594/MUM/2015, filed on April 17, 2015, the entirety of which is hereby incorporated by reference.

TECHNICAL FIELD
[002] The embodiments herein generally relate to digital image processing, and, more particularly, to determining ground truth in lane departure warning.

BACKGROUND
[003] There are known driving support apparatuses making various controls during driving, especially on the express highway. There are also many know methods which support lane marking or lane recognition. It is necessary to accurately estimate positions of lane lines in order to appropriately drive a vehicle along the lane lines. The automotive imaging is a recent trend of research to assist drivers and finally to move forward to achieve the goal of designing a driver-less car. Along with state-of-art algorithm, state-of-art validation framework is also a requirement to ensure quality of the system.

[004] In automotive imaging an offline video marking ground-truth determination is a tedious task by the tester or a user. Typically a camera captures in the frequency of 30 image frames per second and marking these manually is a tedious task. Further, scenarios like sudden variation in the environment, sudden inclusion of foreign object on the lane marks, multiple lanes in the field of view of the camera are the major challenges. Since ground truth value will be the reference to judge the accuracy of lane departure applications, even minor errors are not acceptable. Available binarization methods may not be compatible with the aforementioned problem scenarios. Hence the tester should be the supervisor of the automated algorithm and maybe able to switch to manual whenever required.

SUMMARY
[005] This summary is provided to introduce aspects related to method and system for ground truth determination for lane departure warning systems and their aspects are further described below in the detailed description. This summary is not intended to identify essential features of the claimed subject matter nor is it intended for use in determining or limiting the scope of the subject matter.

[006] In one implementation, a method for ground truth determination in lane departure warning is disclosed. The method may comprise receiving lane images as an input from an image capturing unit. Further, processing the lane images into a plurality of time sliced images captured at different time frames. The method may further determining an intensity profile of each of the plurality of time sliced images and smoothening the intensity profile to obtain a smoothened histogram. Further, obtaining a threshold value for each of the time-sliced images by extracting a minima between a first maxima and a successive second maxima of the smoothened histogram. The method may further comprise refining the threshold value of the time-sliced images by segmenting the time sliced images to obtain a plurality of individual time slices, calculating a statistical mean variation of the intensity profile of each of the individual time slices and grouping the individual time slices having a mean intensity within a predefined range in to a cluster of slices and determining a minima between a first maxima and a successive second maxima of the intensity profile of the cluster of slices. The method may further comprise detecting a lane marking of the lane by extracting the mid-points of the marking based on the refined threshold value of the time sliced images and determining the ground truth value based on the lane marking of the lane for validating a lane departure warning.

[007] The method may further comprise validating a lane departure warning application output based on a pixel position detected by the lane departure warning application, with respect to the determined ground truth, by calculating the Percentage Detection Accuracy = True Detection/Total Boundary Detection * 100; wherein Total Boundary Detection is number of pixels in the Ground Truth and True Detection is number of pixels in the lane departure warning application.
[008] The method may further comprise sub-grouping the individual time slices having a mean intensity outside a predefined range in to a cluster of slices and determining a minima between a first maxima and a successive second maxima of the intensity profile of the cluster of slices.

[009] The method of refining the threshold value further comprise further comprises allowing a user to perform at least one of selecting the number of frames of the lane and defining the boundaries of the lane.

[0010] The method of determining ground truth may further comprise filling discontinuities in the lane by interpolation through lane boundary correspondence, wherein the lane boundary correspondence comprises detecting lane marks by measuring a distance between a left and a right mark of the lane and mapping to the image frame.

[0011] In one implementation, a system for ground truth determination in lane departure warning is disclosed. The system comprises an image capturing unit and an image database communicatively coupled to the image capturing unit; the image database configured to receive lane images from the image capturing unit. The system further comprises of an image processing unit. The image processing unit comprises of a processor and a memory coupled to the processor. The processor executes plurality of modules stored in the memory. The plurality of modules comprises, a receiving module may receive lane image as an input from the image database. Further, an image processing module may the lane images received from the receiving module to obtain plurality of time slice images captured at different time frames. Furthermore, the processing module obtains a threshold value for each of the time-sliced images by extracting a minima between a first maxima and a successive second maxima of the smoothened histogram. Furthermore, processing module refines the threshold value of the time-sliced images by: segmenting the time sliced images to obtain a plurality of individual time slices, calculating a statistical mean variation of the intensity profile of each of the individual time slices and grouping the individual time slices having a mean intensity within a predefined range in to a cluster of slices and determining a minima between a first maxima and a successive second maxima of the intensity profile of the cluster of slices. Further a detection module may detect lane marking of the lane by extracting the mid-points of the marking based on the refined threshold value of the time sliced images; and determine the ground truth value based on lane markings.

[0012] The plurality of modules further comprises a validation module for validating for validating a lane departure warning application output based on a pixel position detected by the lane departure warning application, with respect to the determined ground truth.

[0013] The processing module may further sub-groups the individual time slices having a mean intensity outside a predefined range in to a cluster of slices and determining a minima between a first maxima and a successive second maxima of the intensity profile of the cluster of slices.

[0014] In another implementation, a non-transitory computer readable medium embodying a program executable in a computing device for determining the ground truth in lane departure warning is disclosed. The program may comprise a program code for receiving lane images as an input from an image capturing unit. The program may further comprise a program code for processing the lane images into a plurality of time sliced images captured at different time frames. The program may further comprise a program code for determining an intensity profile of each of the plurality of time sliced images and smoothening the intensity profile to obtain a smoothened histogram. The program may further comprise a program code for obtaining a threshold value for each of the time-sliced images by extracting a minima between a first maxima and a successive second maxima of the smoothened histogram. The program may further comprise a program code for refining the threshold value by segmenting the time sliced images to obtain a plurality of individual time slices, calculating a statistical mean variation of the intensity profile of each of the individual time slices and grouping the individual time slices having a mean intensity within a predefined range in to a cluster of slices and determining a minima between a first maxima and a successive second maxima of the intensity profile of the cluster of slices. The program may further comprise a program code for detecting a lane marking of the lane by extracting the mid-points of the marking based on the refined threshold value of the time sliced images and a program code for determine the ground truth value based on the lane marking of the lane for validating a lane departure warning.

BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The embodiments herein will be better understood from the following detailed description with reference to the drawings, in which:
[0016] FIG. 1 illustrates a network implementation of a server and a device for determining ground truth in a lane departure warning, in accordance with an example embodiment of the present disclosure;
[0017] FIG. 2 illustrates the device, in accordance with an example embodiment of the present disclosure;
[0018] FIG. 3 illustrates a detailed working of the device, in accordance with an example embodiment of the present disclosure;
[0019] FIGS. 4(a) and 4 (b) illustrates an original histogram profile and smoothed histogram of a time sliced gray image , in accordance with an example embodiment of the present disclosure;
[0020] FIGS. 5(a) and 5 (b) illustrate grouping and sub-grouping of slices based on statistical mean, in accordance with an example embodiment of the present disclosure;
[0021] FIGS. 6 (a), 6 (b) and 6 (c) illustrates an original lane, original lane image in gray scale and a binary image of the lane marking obtained, in accordance with an example embodiment of the present disclosure;
[0022] FIGS. 7(a) and 7(b) illustrates mid-point mapping on the original frame by ground truth and combination of ground truth and lane boundary correspondence, in accordance with an example embodiment of the present disclosure; and
[0023] FIG.8 illustrates a flow diagram for determining ground truth in a lane detecting warning, in accordance with an example embodiment of the present disclosure.

DETAILED DESCRIPTION
[0024] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.

[0025] While aspects of described device and method for detecting objects at multiple ranges simultaneously may be implemented in any number of different computing devices, environment, and/or configuration, the embodiments are described in the context of the following exemplary devices.

[0026] FIG. 1 illustrates a network implementation of a server and a device for determining ground truth in a lane departure warning, in accordance with an example embodiment of the present disclosure. In one embodiment, the environment 100 includes at least one device, for example a device 102, a server 104, an image capturing unit 106, and a communication network 108. It will be noted herein that the number of devices and/or networks, illustrated in FIG. 1, is provided for explanatory purposes only. In practice or some example scenarios, there may be additional or fewer devices and/or networks; different devices and/or networks; or differently arranged devices and/or networks than illustrated in FIG. 1. Also, in some implementations, one or more of the devices of environment 100 may perform one or more functions described as being performed by another one or more of the devices of environment 100. In one example, the image capturing device 106 and the server 104 may be combined into a single device and/or system. Devices and/or networks of environment 100 may interconnect via wired connections, wireless connections, or a combination of wired and wireless connections.

[0027] The device 102 may include any computation or communication device that is capable of communicating via the communication network 108. For example, the device 102 may be implemented in a variety of communication devices such as a laptop computer, a desktop computer, a notebook, a workstation, a mobile phone, a personal digital assistant (PDA), and so on. The device 102 is further configured to determine the ground truth in lane departure warning system by image processing, for example, the device 102 may be an image processing unit.

[0028] The server 104 may include one or more server devices, or other types of computation and communication devices, that provide content. For example, server 104 may host a website that can be accessed, by the device 102, to receive content (e.g., web pages, video, audio, images, advertising content, text, data, and/or some combination thereof), and/or a service For example, the server 104 may be accessed by a user of the device 102 for accessing, for example, lane images captured by an image capturing unit 108. The server 104 may receive an access request from the device 102 for facilitating access to lane images. In response to the request, the server 104 may redirect the device 102 to the image capturing unit 108 for the user to access the images. The server 104 may provide the content and/or service to device 102 via network 108. In an alternative embodiment, the server 104 may host an application that communicates with network 108 to process the request from the user.

[0029] FIG. 2 is a block diagram of a device, for example, the device 102 of FIG. 1, in accordance with an example embodiment. The device 102 includes or is otherwise in communication with at least one processor such as a processor 202, at least one memory such as a memory 204, and a user interface 206. The processor 202, the memory 204, and the user interface 206 may be coupled by a system bus such as a system bus or a similar mechanism (not shown in Figure).Although FIG. 2 shows example components of the device 102, in other implementations, the device 102 may contain fewer components, additional components, different components, or differently arranged components than depicted in FIG. 2.

[0030] The processor 202 may include circuitry implementing, among others, audio and logic functions associated with the communication. The processor 202 may also include the functionality to encode messages and/or data or information. The processor 202 may include, among other things, a clock, an arithmetic logic unit (ALU) and logic gates configured to support operation of the processor 202. Further, the processor 202 may include functionality to execute one or more software programs, which may be stored in the memory 204 or otherwise accessible to the processor 202.

[0031] The memory 204, may store any number of pieces of information, and data, used by the device 102 to implement the functions of the device 102. The memory 204 may include for example, volatile memory and/or non-volatile memory. Examples of volatile memory may include, but are not limited to volatile random access memory (RAM). The non-volatile memory may additionally or alternatively comprise an electrically erasable programmable read only memory (EEPROM), flash memory, hard drive, or the like. The memory 204 may be configured to store information, data, applications, instructions or the like for enabling the device 200 to carry out various functions in accordance with various example embodiments. Additionally or alternatively, the memory 204 may be configured to store instructions which when executed by the processor 202 causes the device 200 to behave in a manner as described in various embodiments. The memory 204 may include modules 208 and data 220.

[0032] The modules 208 include routines, programs, objects, components, data structures, etc., which perform particular tasks or implement particular abstract data types. In one implementation the modules 208 may include a receiving module 209, an image processing module 210, detecting module 212, validating module 214, and other modules 220. The other modules 220 may include programs or coded instructions that supplement applications and functions of the device 102.

[0033] The data 220, amongst other things, serves as a repository for storing data processes, received, and generated by one or more of the module 208. The data 220 may also include an image database 222, and other data 224.

[0034] FIG. 3 illustrates detailed working of the block diagram of device 102 as depicted in FIG.2, in accordance with an example embodiments of the present disclosure. The image/video of a lane is captured using any conventionally available image capturing unit 108 and the recorded image/video set is stored in the image database 222. In one of the example embodiment, the image database 222 and may be located within the device 102 as shown in FIG. 3. In another example embodiment the image database 222 may be located remotely from the device 102. For example, the image location would vary with respect to movement of the image capturing unit 108 mounted on a vehicle. The variation may be with respect to intensity profile and environmental illumination profile.

[0035] The stored images are received and read by the receiving module 208 and processed in the image processing module 210 using one or more processors 202. As a first step of the image processing, the images are time sliced. In an example embodiment, a recorded video obtained from the image capturing unit 108 contains plurality of image frames. Each frame is taken at different time slots of the recorded image, for example,first frame at 1s, second frame at 2s, third frame at 3s, and likewise, in this case the capture rate of the frame is 1s. Each frame is of same size andare uniformly sliced to containmultiple rows, for example each frame may contain row 1 to row 30. A particular row, for example 10th row amongst multiple rows is selected and it becomes the first time slice image. Likewise, 10th row from other frames are selected to obtain plurality of time slice images.

[0036] Further, the image processing module 210 may determine the intensity profile or histogram of each time sliced image.The histogram of the time sliced image may contain some additional peaks and spikes excluding the well-defined symmetric near Gaussian intensity profile (as shown in FIG. 4a). Hence, a pre-smoothing operation is performed on the histogram in order to extract the low pass filtered envelop of the histogram or intensity profile. Histogram envelope is extracted through smoothing process (as shown in FIG. 4b).Further the processing module 210 determines a threshold value by detecting a minima between two well-defined maxima of the smoothened histogram. The well-defined maxima contains a first maxima, where the first maxima is a highest peak of the smoothened histogram and a second maxima where the successive second maxima is a following highest peak of the first maxima. Herein, the minima between these two peaks is considered as the threshold value. This technique may be referred as Min-Between-Max-Thresholding (MBMT).In an example embodiment, the intensity profile or the histogram of the time sliced image have highest peak at intensity around the mid-intensity range. The successive next highest peak with a similar symmetry of intensity profile of the time-sliced image is around a high intensity which corresponds to the lane marking.

[0037] Further, the image processing module 210refines the threshold value by again applying the above technique (MBMT). In this stage, the time slice images are uniformly segmented within a frame to obtain an individual slice. The statistical mean variation of the each individual slice is calculated. Further, the image processing module 210, groups (uniform slicing) the individual slices having a mean intensity values within a predefined range in to a cluster of slicesand a mean between a first maxima and a successive second maxima of intensity profile of the cluster of slices is determined. In an example embodiments,30 slices of the time slice images are considered. Based on the value of the statistical mean, the slices are grouped and localized, for example, a predefined range of 180±10 is considered as a single group (as shown in FIG. 5a) and slices having mean in that region are grouped together and MBMT technique is applied. If a drastic change in mean is observed, a value outside the predefined range (as shown in FIG. 5b), further sub-grouping is performed (non-uniform slicing) and MBMT technique is applied. The drastic change in mean may be due to presence of an obstacle in the slice.

[0038] Further, after applying the MBMT technique,the time slice images are in the form of a binary image(as shown in FIG. 6C), where the lane marking are represented as white pixels and anything other than lane marking as black pixels. Before applying MBMT the lane image is in gray scale (as shown in FIG. 6b) and original lane image (as shown in FIG. 6a). Further, the detection module 212 detects the lane markings by extracting the mid-points of two white patches (as shown in FIG. 7) of a lane which corresponds to a lane markings, the mid-points are extracted based on the refined threshold value obtained by applying the MBMT. The mid-point of each lane width is detected as ground truth lane points which is mapped to the original frame of the video/image. Herein, themidpoints of the lane markingsare inverse mapped to the original frames of the video.This is extend to multiple rows to determine multiple points on the lane marking and mapped on to the original frames(as shown in FIG. 7a).to determine the ground truth for validating a lane departure warning.

[0039] Further, any gap in the time-slice due to the structure of the lane, for example, discontinued lane, occluded lane, dotted lane, noise is filled up by interpolation through lane boundary correspondence (LBC). In LBC, the distance between adjacent lane markings that is the left and right mark of a lane are measured whenever a lane marks on both sides are detected. The gaps are filled using the following equation and mapped to the original frame(as shown in FIG 7b):
d2 = (d1×X+d3×Y)/(X+Y)
Wherein the distance between the corresponding lanes where MBMT detected lane markings are d1 and d3 respectively, then unknown lane center can be marked by determining d2 through d1, d2 and row distances between unknown to upper known lane (X) and unknown to lower known lane marks (Y) (as shown in 7c)

[0040] Further the validation module 214 facilitates the validation of any lane warning application with respect to the determined ground truth. The validation of the lane departure warning may be based on pixelposition detections or warnings given by the complete system of lane departure warning. In an example embodiment, pixel based detection accuracy is described. The boundary around the ground truth value that is the lane mid-points obtained from the above described steps is determined. The boundary, around the ground truth, is the left and right edge of the lane marking is considered as actual or total detection boundary. The application (any lane departure warning application) detections line on the lane marking within the actual or total boundary is considered as true detection. The accuracy of any lane departure application is calculated using the formula
Percentage PixelDetectionAccuracy = True Detection / Total Boundary Detection * 100
Where Actual Detection ? No of Pixels in the Ground Truth or Actual boundary.
True Detection ? No of Pixels in the Application lane with in Actual boundary
Further, pixel detections outside the actual or total detection boundary of Ground Truth is excluded in calculating the accuracy of the lane departure. The pixel detection outside the actual or total detection, i.e., anything other than the actual boundary is considered as false detection.

[0041] Further, the MBMT is discussed in the above steps is based on intensity profile and statistical divergence.The ground truth is used as a baseline frame work and is considered as reference at the validation step minor error needs to be taken care of. Hence this method also allows manual intervention at two stages.

[0042] The device 102 further includes an option for manual intervention at two stages (a) (a) allowing a user to definenumber of frames that needs to be processed in the image processing module.
(b) allowing a user to select the boundaries around the lane that will be considered as lane image (excluding the noises), for image processing.
The device 102 may include a user defined boundary selection window (not shown in figure). This helps a user to select a single lane out of multiple lanes and improve the quality of lane by selecting the required boundary around the lane. The user may also have a provision to reject and redraw the boundary of the lane. Further, it includes an option to run and pause the selection until the lanes are within a chosen boundary.

[0043] FIG. 8 illustrates a flow diagram of a method 800 for determining ground truth in a lane departure warning, in accordance with the present disclosure.

[0044] At 802, the method includes receiving lane images as an input from an image capturing unit, by at least one image capturing unit mounted on a vehicle. For example, the image is captured by one or more image capturing unit mounted on a vehicle, wherein the image capturing unit captures continuous image of a lane. At 804, the lane images are processed to create plurality of time slice images. Herein, the time slice images are created by capturing the lane images at different time and thereby creating multiple frames. The frames comprises of multiple rows and each row taken at different time slot is considered a time sliced image. In one of the example embodiments, a user may select the number of frames of the lane and define the boundaries of the lane to be processed. At 806, intensity profile of each time sliced image is determined. Further, the intensity profiles containing some additional peaks and spikes are smoothened. At 808, threshold value of the time-sliced image is obtained by extracting a minima between a first maxima and a successive second maxima of the smoothened histogram. Herein, the first maxima is a highest peak of the smoothened histogram and the successive second maxima is a following highest peak of the first maxima (as shown in FIG. 4).

[0045] At 810, the threshold value of the time-sliced image is further refined by segmenting the time sliced images to obtain a plurality of individual time slices and a statistical mean variation of the intensity profile of each of the individual time slices is calculated. The statistical mean variation is based on the statistical divergence between each slices of the time sliced images. Further, at 812 the individual slices having a mean intensity within a predefined range are grouped in to a cluster of slices and a minima between a first maxima and a successive second maxima of the intensity profile of the cluster of slices is determined. At 814, the lane marking of the lane are detected by extracting mid-points of the marking based on the refined threshold value of the time sliced images. Herein, the time sliced images is a binary image and lane markings are represented as white pixels and anything other than lane marking as black pixels in the binary image of the lane.

[0046] Further, at 816, the ground truth value based on lane markings is determined. The ground truth value is further corrected by filling discontinuities in the lane by interpolation through lane boundary correspondence, wherein lane boundary correspondence comprises detecting lane marks by measuring the distance between left and right mark of a lane and mapping to the image frame. The discontinuities in a lane may be discontinued lane, occluded lane, dotted lane and noise. Further, the determined ground truth is applied for validating a lane departure application output based on pixel position detected by the lane departure application. The detection accuracy is calculated with respect to the determined ground truth. ,CLAIMS:WE CLAIM
1. A computer implemented method for ground truth determination in a lane departure warning, comprising:
receiving a lane image as an input from an image capturing unit;
processing the lane images into a plurality of time sliced images captured at different time frames;
determining an intensity profile of each of the plurality of time sliced images and smoothening the intensity profile to obtain a smoothened histogram;
obtaining a threshold value for each of the time-sliced images by extracting a minima between a first maxima and a successive second maxima of the smoothened histogram;
refining the threshold value of the time-sliced images by:
segmenting the time sliced images to obtain a plurality of individual time slices, calculating a statistical mean variation of the intensity profile of each of the individual time slices and grouping the individual time slices having a mean intensity within a predefined range in to a cluster of slices and determining a minima between a first maxima and a successive second maxima of the intensity profile of the cluster of slices;
detecting a lane marking of the lane by extracting mid-pointsof the marking based on the refined threshold value of the time sliced images; and
determining the ground truth value based on the lane marking of the lane for validating a lane departure warning.

2. The method of claim 1, further comprising validating a lane departure warning application output based on a pixel position detected by the lane departure warning application, with respect to the determined ground truth, by calculating the
Percentage Detection Accuracy = True Detection/Total Boundary Detection * 100; wherein
Total Boundary Detection is number of pixels in the Ground Truth and
True Detection is number of pixels in the lane departurewarning application.

3. The method of claim 2, wherein the pixel detection outside the actual or total detection are excluded.

4. The method of claim 1, further comprising sub-grouping the individual time slices having a mean intensity outside a predefined range in to a cluster of slices and determining a minima between a first maxima and a successive second maxima of the intensity profile of the cluster of slices.

5. The method of claim 1, processing the time slice images further comprises allowing a user to perform at least one of selecting the number of frames of the lane and defining the boundaries of the lane.

6. The method of claim 1, wherein the time sliced images are formed by slicing the lane images at different time frames, wherein each time frame comprises multiple rows.

7. The method of claim 1, determining ground truth further comprises filling discontinuities in the lane by interpolation through lane boundary correspondence, wherein the lane boundary correspondence comprises detecting lane marks by measuring a distance between a left and a right mark of the lane and mapping to the image frame.

8. The method of claim 7, wherein the discontinuities in the lane is at least one of discontinued lane, occluded lane, dotted lane and noise.

9. The method of claim 1, wherein the statistical mean variation is based on the statistical divergence between each individual time slice of the time sliced images.

10. The method of claim 1, wherein the first maxima is a highest peak of the smoothened histogram and the successive second maxima is a following highest peak of the first maxima.

11. The method of claim 1, wherein determining the ground truth further comprises inverse mapping the detected midpoint on to the image frames obtained by the image capturing unit.

12. The method of claim 1, wherein the time sliced images after obtaining the refined threshold values is a binary image.

13. The method of claim 1, wherein the lane markings are represented as white pixels and anything other than lane markings as black pixels in a binary image of the lane.

14. A system for ground truth determination in a lane departure warning, comprising:
an image capturing unit;
an image database communicatively coupled to the image capturing unit; the image database configured to receive lane images from the image capturing unit;
an image processing unit, wherein the unit comprising:
a processor;
a memory coupled to the processor; the memory comprising:
a receiving module for receiving lane image as an input from the image database;
an image processing module for
processing the lane images received from the receiving module to obtain plurality of time slice images captured at different time frames;
obtaining a threshold value for each of the time-sliced images by extracting a minima between a first maxima and a successive second maxima of the smoothened histogram;
refining the threshold value of the time-sliced images by: segmenting the time sliced images to obtain a plurality of individual time slices, calculating a statistical mean variation of the intensity profile of each of the individual time slices and grouping the individual time slices having a mean intensity within a predefined range in to a cluster of slices and determining a minima between a first maxima and a successive second maxima of the intensity profile of the cluster of slices; and
a detection module fordetecting lane marking of the lane by extracting mid-points of the marking based on the refined threshold value of the time sliced imagesand determining the ground truth value based on the lane marking.

15. The system of claim 14, the memory further comprises a validation module for validating a lane departure warning application output based on a pixel position detected by the lane departure warning application, with respect to the determined ground truth.

16. The system of claim 14, the image processing module further comprising sub-grouping comprising sub-grouping the individual time slices having a mean intensity outside a predefined range in to a cluster of slices and determining a minima between a first maxima and a successive second maxima of the intensity profile of the cluster of slices.

17. The system of claim 14, wherein the image is captured by one or more image capturing unit mounted on a vehicle, wherein the image capturing unit captures continuous image of a lane.

18. A non-transitory computer storage medium having instructions that, when executed by a computing device cause the computing device to:
receive lane images as an input from an image capturing unit;
process the lane images into a plurality of time sliced images captured at different time frames;
determine an intensity profile of each of the plurality of time sliced images and smoothening the intensity profile to obtain a smoothened histogram;
obtain a threshold value for each of the time-sliced images by extracting a minima between a first maxima and a successive second maxima of the smoothened histogram;
refine the threshold value of the time-sliced images by segmenting the time sliced images to obtain a plurality of individual time slices, calculating a statistical mean variation of the intensity profile of each of the individual time slices and grouping the individual time slices having a mean intensity within a predefined range in to a cluster of slices and determining a minima between a first maxima and a successive second maxima of the intensity profile of the cluster of slices;
detect a lane marking of the lane by extracting the mid-pointsof the marking based on the refined threshold value of the time sliced images; and
determine the ground truth value based on the lane marking of the lane for validating a lane departure warning.

19. The non-transitory computer-readable medium as claimed in claim 18, further comprise validating a lane departure warning application output based on a pixel position detected by the lane departure warning application, with respect to the determined ground truth.

20. The non-transitory computer-readable medium as claimed in claim 18, wherein the image processing further comprise sub-grouping comprising sub-grouping the individual time slices having a mean intensity outside a predefined range in to a cluster of slices and determining a minima between a first maxima and a successive second maxima of the intensity profile of the cluster of slices.