Image coding method, image decoding method, image coding apparatus, image decoding apparatus, and image coding and decoding apparatus

• US 9,159,142 B2
• Filed: 07/31/2014
• Issued: 10/13/2015
• Est. Priority Date: 07/18/2011
• Status: Active Grant

• Current Assignee: Sun Patent Trust
• Original Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Inventors: Sasai, Hisao, Nishi, Takahiro, Shibahara, Youji, Sugio, Toshiyasu, Tanikawa, Kyoko, Matsunobu, Toru
• Primary Examiner(s): Mehta, Bhavesh
• Assistant Examiner(s): MOYER, ANDREW M
• Application Number:
  US14/448,202
• Publication Number:
  US 20140341286A1
• Time in Patent Office: 439 Days
• US Class Current: 1/1
• CPC Class Codes: G06T 9/004 Predictors, e.g. intraframe, interframe coding
• CPC Class Codes: H04N 19/13 Adaptive entropy coding, e.g. adaptive variable length coding [AVLC] or context adaptive binary arithmetic coding [CABAC]
• CPC Class Codes: H04N 19/136 Incoming video signal characteristics or properties
• CPC Class Codes: H04N 19/184 the unit being bits, e.g. of the compressed video stream
• CPC Class Codes: H04N 19/186 the unit being a colour or a chrominance component
• CPC Class Codes: H04N 19/44 Decoders specially adapted therefor, e.g. video decoders which are asymmetric with respect to the encoder
• CPC Class Codes: H04N 19/593 involving spatial prediction techniques
• CPC Class Codes: H04N 19/91 Entropy coding, e.g. variable length coding [VLC] or arithmetic coding

Abstract

An image decoding device includes a processor and storage configured to receive a bitstream from a server based on an instruction sent from an apparatus, decode an image on a block-by-block basis, from the bitstream and send the image to a display apparatus. The decoding includes obtaining first, second, third and fourth data, where context adaptive binary arithmetic decoding is performed on the first data, bypass decoding is performed on the second data, context adaptive binary arithmetic decoding is performed on the third data, and bypass decoding is separately performed on the fourth data. Four luma intra prediction modes are derived from a respective one of four luma context-dependent segments and a corresponding one of four luma context-independent segments for four subblocks in an image block, and one chroma intra prediction mode is derived from one chroma context-dependent segment and one chroma context-independent segment for the image block.

Claims

1. A decoding device, comprising

at least one processor;

and

storage coupled to the at least one processor;

wherein the at least one processor is configured to;

receive a bitstream from a server based on an instruction sent from an apparatus;

decode an image, on a block-by-block basis, from the bitstream; and

send the image to a display apparatus coupled to the decoding device,

wherein the decoding further includes;

obtaining, in a following order, first data including four coded luma context-dependent segments, second data including four coded luma context-independent segments, third data including one coded chroma context-dependent segment and fourth data including one coded chroma context-independent segment from the bitstream for an image block in the image;

performing context adaptive binary arithmetic decoding on the first data to generate four luma context-dependent segments;

performing bypass decoding on the second data to generate four luma context-independent segments;

performing context adaptive binary arithmetic decoding on the third data to generate one chroma context-dependent segment;

performing bypass decoding on the fourth data to generate one chroma context-independent segment;

deriving four luma intra prediction modes from a respective one of the four luma context-dependent segments and a corresponding one of the four luma context-independent segments for four subblocks in the image block; and

deriving one chroma intra prediction mode from the one chroma context-dependent segment and the one chroma context-independent segment for the image block, and

wherein the bitstream includes, in the following order, the first data, the second data, the third data and the fourth data when the bitstream is compliant with a first standard, and the bitstream includes, in the following order, four coded luma intra prediction modes and one coded chroma intra coded mode when the bitstream is compliant with a second standard different from the first standard.

2. The decoding device according to claim 1, wherein the receiving further includes receiving the bitstream corresponding to the instruction from a plurality of bitstreams.

3. A decoding device, comprising

at least one processor;

and

storage coupled to the at least one processor;

wherein the at least one processor is configured to;

receive a bitstream transmitted from an apparatus;

decode an image, on a block-by-block basis, from the bitstream; and

send the image to a display apparatus coupled to the decoding device,

wherein the decoding further includes;

obtaining, in a following order, first data including four coded luma context-dependent segments, second data including four coded luma context-independent segments, third data including one coded chroma context-dependent segment and fourth data including one coded chroma context-independent segment from the bitstream for an image block in the image;

performing context adaptive binary arithmetic decoding on the first data to generate four luma context-dependent segments;

performing bypass decoding on the second data to generate four luma context-independent segments;

performing context adaptive binary arithmetic decoding on the third data to generate one chroma context-dependent segment;

performing bypass decoding on the fourth data to generate one chroma context-independent segment;

deriving four luma intra prediction mode respectively from one of the four luma context-dependent segments and a corresponding one of the four luma context-independent segments for four subblocks in the image block; and

deriving one chroma intra prediction mode from the one chroma context-dependent segment and the one chroma context-independent segment for the image block, and

wherein the bitstream includes, in the following order, the first data, the second data, the third data and the fourth data when the bitstream is compliant with a first standard, and the bitstream includes, in the following order, four coded luma intra prediction modes and one coded chroma intra coded mode when the bitstream is compliant with a second standard different from the first standard.

4. The decoding device according to claim 3, wherein the receiving further includes receiving the bitstream corresponding to the instruction from a plurality of bitstreams.