Methods and Apparatuses for Coding and Decoding Depth Map

Abstract

A method for coding and decoding a depth map includes determining to perform simplified depth coding (SDC) decoding according to a flag of an SDC mode, determining a size of an image block and a maximum prediction size, determining an intra-frame prediction mode, in a case in which the size of the image block is greater than the maximum prediction size, splitting the image block to obtain N split image blocks, and performing the SDC decoding on the N split image blocks using the intra-frame prediction mode.

What is claimed is: 
     
         1 . A method for simplified depth decoding, comprising:
 obtaining a flag of simplified depth coding (SDC), wherein a value of the flag indicates that SDC decoding is used for an image block;   determining an intra prediction mode of the image block;   splitting the image block to obtain N split image blocks when a size of the image block is greater than a maximum prediction size, wherein a size of each of the N split image blocks is the same as the maximum prediction size;   obtaining a residual when performing the SDC decoding on an i th  split image block of the N split image blocks;   obtaining prediction data of the i th  split image block using the intra prediction mode that is used when the SDC is performed on the image block;   determining an average value of the prediction data based on a plurality of pixel values in the prediction data and a number of pixels in the i th  split image block; and   determining a reconstruction value of the i th  split image block according to the average value of the prediction data and the residual to perform the SDC decoding on the i th  split image block.   
     
     
         2 . The method of  claim 1 , wherein the intra prediction mode is a depth modeling mode (DMM), a planar mode, or a direct current mode. 
     
     
         3 . The method of  claim 1 , wherein splitting the image block to obtain the N split image blocks comprises:
 splitting the image block to obtain split image blocks according to the size of the image block and the maximum prediction size;   obtaining the N split image blocks when a size of the split image blocks is the same as the maximum prediction size; and   further splitting the split image blocks until the size of the split image blocks is the same as the maximum prediction size when a size of the split image blocks is greater than the maximum prediction size to obtain the N split image.   
     
     
         4 . The method of  claim 1 , wherein the average value of the prediction data of the i th  split image block is determined based on the following formula:
     PV   i   =ΣP Pix i [ x,y ]/sumOf P Pix,   wherein PV i  is the average value of the prediction data of the i th  split image block, PPix i [x,y] is a pixel value in the prediction data with coordinates that are [x,y] in the i th  split image block, and sumOfPPix is the number of pixels in the i th  split image block.   
     
     
         5 . The method of  claim 1 , wherein the reconstruction value of the i th  split image block is determined based on the following formula:
     R   i   =PV   i   +S   i      
       wherein R i  is the reconstruction value of the i th  split image block, PV i  is the average value of the prediction data of the i th  split image block, and S i  is a residual of the i th  split image block among the N split image blocks. 
     
     
         6 . A method for simplified depth coding (SDC), comprising:
 determining an intra prediction mode of the image block;   splitting the image block to obtain N split image blocks when a size of the image block is greater than a maximum prediction size, wherein a size of the N split image blocks is the same as the maximum prediction size; and   determining prediction data of an i th  split image block of the N split image blocks using the intra prediction mode;   determining an average value of the prediction data based on a plurality of pixel values in the prediction data of the i th  split image block and a number of pixels in the i th  split image block;   determining an average value of raw data of the i th  split image block;   determining a residual of the i th  split image block according to the average value of the prediction data and the average value of the raw data; and   coding the residual of the i th  split image block to perform SDC on the i th  split image block.   
     
     
         7 . The method of  claim 6 , wherein the-intra prediction mode is a depth modeling mode (DMM), a planar mode, or a direct current mode. 
     
     
         8 . The method of  claim 6 , wherein splitting the image block to obtain N split image blocks comprises:
 splitting the image block to obtain split image blocks according to the size of the image block and the maximum prediction size;   obtaining the N split image blocks when a size of the split image blocks is the same as the maximum prediction size; and   further splitting the split image blocks until the size of the split image blocks is the same as the maximum prediction size when a size of the split image blocks is greater than the maximum prediction size to obtain the N split image.   
     
     
         9 . The method of  claim 6 , wherein the average value of the prediction data is determined based on the following formula:
     PV   i   =ΣP Pix i [ x,y ]/sumOf P Pix,   
       wherein PV i  is the average value of the prediction data of the i th  split image block, PPix i [x,y] is a pixel value in the prediction data with coordinates that are [x,y] in the i th  split image block, and sumOfPPix is the number of pixels in the i th  split image block. 
     
     
         10 . The method of  claim 6 , wherein the average value of the raw data is determined based on the following formula:
     BV   i   =ΣB Pix i [ x,y ]/sumOf B Pix,   
       wherein BV i  is the average value of raw data of the i th  split image block, BPix i [x,y] is a pixel value in the raw data with coordinates that are [x,y] in the i th  split image block, and sumOfBPix is the number of pixels in the i th  split image block. 
     
     
         11 . The method of  claim 6 , wherein the residual of the i th  split image block is determined based on the following formula:
     S   i   =PV   i   −BV   i ,   
       wherein S i  is the residual of the i th  split image block, PV i  is the average value of the prediction data, and BV i  is the average value of raw data. 
     
     
         12 . The method of  claim 6 , further comprising performing SDC on the image block according to the intra prediction mode when the size of the image block is less than or equal to the maximum prediction size. 
     
     
         13 . A decoding apparatus comprising:
 a memory storing instructions; and   a processor configured to execute the instructions to:
 determine to use simplified depth coding (SDC) decoding according to a flag of SDC; 
 determine an intra prediction mode that is used when SDC is performed on the image block; 
 split the image block to obtain N split image blocks when a size of the image block is greater than a maximum prediction size, wherein a size of the N split image blocks is the same as the maximum prediction size and the N split image blocks are all transform blocks; 
 obtain a residual when performing the SDC decoding on an i th  split image block of the N split image blocks; 
 obtain prediction data of the i th  split image block by using the intra prediction mode that is used when the SDC is performed on the image block; 
 determine an average value of the prediction data based on a plurality of pixel values in the prediction data and a number of pixels in the i th  split image block; and 
 determine a reconstruction value of the i th  split image block according to the average value of the prediction data and the residual to perform the SDC decoding on the i th  split image block. 
   
     
     
         14 . The decoding apparatus of  claim 13 , wherein the processor is further configured to execute the instructions to:
 split the image block to obtain split image blocks according to the size of the image block and the maximum prediction size;   obtain the N split image blocks when a size of the split image blocks is the same as the maximum prediction size; and   further split the split image blocks until the size of the split image blocks is the same as the maximum prediction size when a size of the split image blocks is greater than the maximum prediction size to obtain the N split image blocks.   
     
     
         15 . The decoding apparatus of  claim 13 , wherein the processor is further configured to execute the instructions to determine the average value of the prediction data based on the following formula:
     PV   i   =ΣP Pix i [ x,y ]/sumOf P Pix,   
       wherein PV i  is the average value of the prediction data, PPix i [x,y] is a pixel value in the prediction data with coordinates that are [x,y] in the i th  split image block, and sumOfPPix is the number of pixels in the i th  split image block. 
     
     
         16 . The decoding apparatus of  claim 13 , wherein the processor is further configured to execute the instructions to determine the reconstruction value of the i th  split image block based on the following formula:
     R   i   =PV   i   +S   i ,   wherein R i  is the reconstruction value of the i th  split image block, PV i  is the average value of the prediction data, and S i  is a residual of the i th  split image block among the N split image blocks.   
     
     
         17 . A coding apparatus for simplified depth coding (SDC), comprising:
 a memory storing instructions; and   a processor configured to execute the instructions to:
 determine an intra prediction mode of the image block; 
 split the image block to obtain N split image blocks when a size of the image block is greater than a maximum prediction size, wherein a size of the N split image blocks is the same as the maximum prediction size; 
 determine prediction data of an i th  split image block of the N split image blocks using the intra prediction mode; 
 determine an average value of the prediction data based on a plurality of pixel values in the prediction data of the i th  split image block and a number of pixels in the i th  split image block; 
 determine an average value of raw data of the i th  split image block; 
 determine a residual of the i th  split image block according to the average value of the prediction data and the average value of the raw data; and 
 code the residual of the i th  split image block to perform SDC on the i th  split image block. 
   
     
     
         18 . The coding apparatus of  claim 17 , wherein the processor is further configured to execute the instructions to:
 split the image block to obtain split image blocks according to the size of the image block and the maximum prediction size;   obtain the N split image blocks when a size of the split image blocks is the same as the maximum prediction size; and   further split the split image blocks until the size of the split image blocks is the same as the maximum prediction size when a size of the split image blocks is greater than the maximum prediction size to obtain the N split image blocks.   
     
     
         19 . The coding apparatus according to  claim 17 , wherein the processor is further configured to execute the instructions to determine the average value of the prediction data of the i th  split image block based on the following formula:
     PV   i   =ΣP Pix i [ x,y ]/sumOf P Pix,   
       wherein PV i  is the average value of the prediction data, PPix i [x,y] is a pixel value in the prediction data with coordinates that are [x,y] in the i th  split image block, and sumOfPPix is the number of pixels in the i th  split image block. 
     
     
         20 . The coding apparatus according to  claim 17 , wherein the processor is further configured to execute the instructions to determine the average value of the raw data of the i th  split image block based on the following formula:
     BV   i   =ΣB Pix i [ x,y ]/sumOf B Pix,   
       wherein BV i  is the average value of raw data, BPix i [x,y] is a pixel value in the raw data with coordinates that are [x,y] in the i th  split image block, and sumOfBPix is the number of pixels in the i th  split image block. 
     
     
         21 . The coding apparatus according to  claim 17 , wherein the processor is further configured to execute the instructions to determine the residual of the i th  split image block based on the following formula:
     S   i   =PV   i   −BV   i ,   
       wherein S i  is the residual of the i th  split image block, PV i  is the average value of the prediction data, and BV i  is the average value of raw data. 
     
     
         22 . The coding apparatus according to  claim 17 , wherein the instructions further cause the processor to be configured to perform SDC on the image block according to the intra prediction mode when the size of the image block is less than or equal to the maximum prediction size.