System and method for performing image data conversion using intraprediction modes

• US 9,813,734 B2
• Filed: 02/09/2017
• Issued: 11/07/2017
• Est. Priority Date: 07/18/2011
• Status: Active Grant

• Current Assignee: Sun Patent Trust
• Original Assignee: Sun Patent Trust
• Inventors: Sasai, Hisao, Nishi, Takahiro, Shibahara, Youji, Sugio, Toshiyasu, Tanikawa, Kyoko, Matsunobu, Toru
• Primary Examiner(s): MOYER, ANDREW M
• Application Number:
  US15/428,665
• Publication Number:
  US 20170155923A1
• Time in Patent Office: 271 Days
• Field of Search: 382238, 382239
• 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

A device and method for decoding, from a bitstream including encoded data, intra prediction modes indicated for decoding an image. Context adaptive binary arithmetic decoding is performed using a variable probability to generate decoded luma context-dependent segments. Context adaptive binary arithmetic decoding is performed using a variable probability to generate a decoded chroma context-dependent segment. Bypass decoding using a fixed probability is performed to generate decoded luma context-independent segments. Luma intra prediction modes are derived from one of the decoded luma context-dependent segments and a corresponding one of the decoded luma context-independent segments. A chroma intra prediction mode is derived from the decoded chroma context-dependent segment.

Claims

1. A decoding device configured to decode, from a bitstream, intra prediction modes indicated in pieces of binary data for decoding an image,

the decoding device comprises:

a processor, and

a storage coupled to the processor,

wherein

the pieces of binary data each includes a plurality of luma context-dependent segments, a plurality of luma context-independent segments, and a chroma context-dependent segment;

the processor performs the following, using the storage;

obtaining, from the bitstream, first encoded data including the plurality of luma context-dependent segments, second encoded data including the plurality of luma context-independent segments, and third encoded data including the chroma context-dependent segment,

performing, on each of the plurality of luma context-dependent segments, context adaptive binary arithmetic decoding using a variable probability to generate a plurality of decoded luma context-dependent segments, and separately perform, on the chroma context-dependent segment, context adaptive binary arithmetic decoding using a variable probability to generate a decoded chroma context-dependent segment,

performing, on each of the plurality of luma context-independent segments, bypass decoding using a fixed probability to generate a plurality of decoded luma context-independent segments,

deriving a plurality of luma intra prediction modes from one of the plurality of decoded luma context-dependent segments and a corresponding one of the plurality of decoded luma context-independent segments, and

deriving one chroma intra prediction mode from the decoded chroma context-dependent segment; and

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

2. A data decoding method, comprising:

decoding, using the at least one processor and from a bitstream, intra prediction modes indicated in pieces of binary data for decoding an image,

wherein the pieces of binary data each includes a plurality of luma context-dependent segments, a plurality of luma context-independent segments, and a chroma context-dependent segment;

wherein the decoding comprises;

obtaining, from the bitstream, first encoded data including the plurality of luma context-dependent segments, second encoded data including the plurality of luma context-independent segments, and third encoded data including the chroma context-dependent segment,

performing, on each of the plurality of luma context-dependent segments, context adaptive binary arithmetic decoding using a variable probability to generate a plurality of decoded luma context-dependent segments, and separately performing, on the chroma context-dependent segment, context adaptive binary arithmetic decoding using a variable probability to generate a decoded chroma context-dependent segment,

performing, on each of the plurality of luma context-independent segments, bypass decoding using a fixed probability to generate a plurality of decoded luma context-independent segments,

deriving a plurality of luma intra prediction modes from one of the plurality of decoded luma context-dependent segments and a corresponding one of the plurality of decoded luma context-independent segments, and

deriving one chroma intra prediction mode from the decoded chroma context-dependent segment; and

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