Image processing apparatus and method

Abstract

An image processing apparatus (encoder, decoder or the like) and method suppress reduction in encoding efficiency. Encoding of coefficient data is skipped in an invalid transform coefficient region, and the coefficient data is encoded in a valid transform coefficient region. Further, for example, the coefficient data in the valid transform coefficient region is encoded in a scan order corresponding to a block shape of a block to be processed. In addition, decoding of encoded data including encoded coefficient data related to an image is skipped in an invalid transform coefficient region, and the encoded data is decoded in a valid transform coefficient region. Further, for example, the encoded data in the valid transform coefficient region is decoded in a scan order corresponding to the block shape of the block to be processed.

1 . An image processing apparatus comprising:
 an encoding unit that skips encoding of coefficient data related to an image in an invalid transform coefficient region and that encodes the coefficient data in a valid transform coefficient region.   
     
     
         2 . The image processing apparatus according to  claim 1 , wherein
 the coefficient data includes valid transform coefficient flag information indicating presence/absence of a valid transform coefficient for each sub-block, and   the encoding unit skips encoding of the valid transform coefficient flag information in the invalid transform coefficient region and encodes the valid transform coefficient flag information in the valid transform coefficient region.   
     
     
         3 . The image processing apparatus according to  claim 2 , wherein
 the coefficient data further includes validity flag information indicating, for each sub-block, presence/absence of a valid transform coefficient with a value that is not 0 and includes a sign and an absolute value of each valid transform coefficient, and   the encoding unit encodes the validity flag information of the sub-block in which the valid transform coefficient flag information is encoded and encodes the sign and the absolute value of each valid transform coefficient of the sub-block in which the validity flag information is true.   
     
     
         4 . The image processing apparatus according to  claim 1 , wherein
 the encoding unit skips encoding of the coefficient data in the invalid transform coefficient region and encodes the coefficient data in the valid transform coefficient region, based on information indicating a block size of a block to be processed and information indicating a range of the valid transform coefficient region.   
     
     
         5 . The image processing apparatus according to  claim 1 , wherein
 the encoding unit encodes the coefficient data in the valid transform coefficient region in a scan order corresponding to the coefficient data.   
     
     
         6 . The image processing apparatus according to claim  5 , wherein
 the encoding unit scans and encodes the coefficient data in the valid transform coefficient region in a vertical direction or a horizontal direction for each sub-block.   
     
     
         7 . The image processing apparatus according to  claim 5 , wherein
 the encoding unit encodes, for each sub-block, the coefficient data in the valid transform coefficient region in a scan order corresponding to a shape of the block to be processed.   
     
     
         8 . The image processing apparatus according to  claim 5 , wherein
 the encoding unit scans and encodes the coefficient data in the valid transform coefficient region for each group of sub-blocks.   
     
     
         9 . The image processing apparatus according to  claim 1 , wherein,
 for luminance components and chroma components of the image, the encoding unit skips encoding of the coefficient data in the invalid transform coefficient region and encodes the coefficient data in the valid transform coefficient region.   
     
     
         10 . An image processing method comprising:
 skipping encoding of coefficient data related to an image in an invalid transform coefficient region and encoding the coefficient data in a valid transform coefficient region.   
     
     
         11 . An image processing apparatus comprising:
 a decoding unit that skips, in an invalid transform coefficient region, decoding of encoded data including encoded coefficient data related to an image and that decodes the encoded data in a valid transform coefficient region.   
     
     
         12 . The image processing apparatus according to  claim 11 , wherein
 the coefficient data includes valid transform coefficient flag information indicating presence/absence of a valid transform coefficient for each sub-block, and   the decoding unit decodes encoded data of the valid transform coefficient flag information in the valid transform coefficient region.   
     
     
         13 . The image processing apparatus according to claim  12 , wherein
 the coefficient data further includes validity flag information indicating, for each sub-block, presence/absence of a valid transform coefficient with a value that is not 0 and includes a sign and an absolute value of each valid transform coefficient, and   the decoding unit decodes encoded data of the validity flag information of the sub-block for which the encoded data of the valid transform coefficient flag information is decoded and decodes encoded data of the sign and the absolute value of each valid transform coefficient of the sub-block in which the validity flag information is true.   
     
     
         14 . The image processing apparatus according to  claim 11 , wherein
 the decoding unit skips decoding of the encoded data in the invalid transform coefficient region and decodes the encoded data in the valid transform coefficient region, based on information indicating a block size of a block to be processed and information indicating a range of the valid transform coefficient region.   
     
     
         15 . The image processing apparatus according to claim  11 , wherein
 the decoding unit decodes the encoded data in the valid transform coefficient region in a scan order corresponding to the coefficient data.   
     
     
         16 . The image processing apparatus according to  claim 15 , wherein
 the decoding unit scans and decodes the encoded data in the valid transform coefficient region in a vertical direction or a horizontal direction for each sub-block.   
     
     
         17 . The image processing apparatus according to  claim 15 , wherein
 the decoding unit decodes, for each sub-block, the encoded data in the valid transform coefficient region in a scan order corresponding to a shape of the block to be processed.   
     
     
         18 . The image processing apparatus according to  claim 15 , wherein
 the decoding unit scans and decodes the encoded data in the valid transform coefficient region for each group of sub-blocks.   
     
     
         19 . The image processing apparatus according to claim  11 , wherein,
 for luminance components and chroma components of the image, the decoding unit skips decoding of the encoded data in the invalid transform coefficient region and decodes the encoded data in the valid transform coefficient region.   
     
     
         20 . An image processing method comprising:
 skipping decoding of encoded data including encoded coefficient data related to an image in an invalid transform coefficient region and decoding the encoded data in a valid transform coefficient region.