# US 11,445,197 B2 · Video decoder with enhanced CABAC decoding > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,445,197 B2 - Document ID: US11445197B2 - Status: Granted - Kind: B2 - Application number: 17/244,371 - Filed: 2021-04-29 - Published: 2021-10-14 - Granted: 2022-09-13 - Earliest claimed: 2011-11-07 - Assignees: Huawei Technologies Co., Ltd. - Applicants: Huawei Technologies Co., Ltd. - Inventors: Kiran Misra; Christopher A. Segall - Web page: https://patentgrep.com/patent/US11445197B2 ## CPC - H04N 19/13: Adaptive entropy coding, e.g. adaptive variable length coding [AVLC] or context adaptive binary arithmetic coding [CABAC] - H04N 19/117: Filters, e.g. for pre-processing or post-processing (sub-band filter banks H04N19/635) - H04N 19/124: Quantisation - H04N 19/15: by monitoring actual compressed data size at the memory before deciding storage at the transmission buffer - H04N 19/159: Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction - H04N 19/176: the region being a block, e.g. a macroblock - H04N 19/44: Decoders specially adapted therefor, e.g. video decoders which are asymmetric with respect to the encoder - H04N 19/46: Embedding additional information in the video signal during the compression process (H04N19/517, H04N19/68, H04N19/70 take precedence) - H04N 19/463: by compressing encoding parameters before transmission - H04N 19/593: involving spatial prediction techniques - H04N 19/70: characterised by syntax aspects related to video coding, e.g. related to compression standards - H04N 19/86: involving reduction of coding artifacts, e.g. of blockiness - H04N 19/91: Entropy coding, e.g. variable length coding [VLC] or arithmetic coding - H04N 19/11: among a plurality of spatial predictive coding modes - H04N 19/182: the unit being a pixel - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract A decoder receives a bitstream containing quantized coefficients representative of blocks of video representative of a plurality of pixels and decodes the bitstream using context adaptive binary arithmetic coding. The context adaptive binary arithmetic coding decodes the current syntax element using the first mode if the current syntax element is intra-coded and selecting between a first set of probable modes and a second set of probable modes, where the first set of probable modes are more likely than the second set of probable modes. The context adaptive binary arithmetic coding decodes the current syntax element using the second mode if the current syntax element is intra-coded and if selecting among one of the second set of probable modes. ## Claims ### Claim 1 A decoder for decoding a prediction mode of a current block, wherein the decoder comprises a regular decoding engine and a bypass decoding engine, the regular decoding engine is used for arithmetic decoding using a context, the bypass decoding engine is used for arithmetic decoding with a bypass decoding process, and wherein the decoder is configured to: decode a first indicator using the regular decoding engine; decode a second indicator using the bypass decoding engine to select the prediction mode of the current block, wherein the prediction mode of the current block is selected from a set of most probable modes when a value of the first indicator is equal to a first value, wherein the set of most probable modes comprises one or more candidate prediction modes generated according to prediction modes of one or more adjacent blocks of the current block; decode a third indicator using the bypass decoding engine to select the prediction mode of the current block, wherein the prediction mode of the current block is not selected from a set of most probable modes when a value of the first indicator is equal to a second value, the second value is different from the first value. ### Claim 2 (depends on 1) The decoder of claim 1, wherein the first value is 1. ### Claim 3 (depends on 1) The decoder of claim 1, wherein the second value is 0. ### Claim 4 An apparatus for decoding a prediction mode of a current block, wherein the apparatus comprises: a regular decoding engine, a bypass decoding engine, a computing hardware, and a non-transitory computer-readable storage medium including computer-executable instructions executed by the computing hardware to perform a method that comprises: decoding a first indicator using the regular decoding engine; decoding a second indicator using the bypass decoding engine to select the prediction mode of the current block, wherein the prediction mode of the current block is selected from a set of most probable modes when a value of the first indicator is equal to a first value, wherein the set of most probable modes comprises one or more candidate prediction modes generated according to prediction modes of one or more adjacent blocks of the current block; decoding a third indicator using the bypass decoding engine to select the prediction mode of the current block, wherein the prediction mode of the current block is not selected from a set of most probable modes when a value of the first indicator is equal to a second value, the second value is different from the first value. ### Claim 5 (depends on 4) The apparatus of claim 4, wherein the first value is 1. ### Claim 6 (depends on 4) The apparatus of claim 4, wherein the second value is 0. ### Claim 7 A computer program product, comprising computer executable instructions stored on a non-transitory computer-readable medium, wherein execution of the instructions by a processor causes the processor to: decode a first indicator using the regular decoding engine; decode a second indicator using the bypass decoding engine to select the prediction mode of the current block, wherein the prediction mode of the current block is selected from a set of most probable modes when a value of the first indicator is equal to a first value, wherein the set of most probable modes comprises one or more candidate prediction modes generated according to prediction modes of one or more adjacent blocks of the current block; decode a third indicator using the bypass decoding engine to select the prediction mode of the current block, wherein the prediction mode of the current block is not selected from a set of most probable modes when a value of the first indicator is equal to a second value, the second value is different from the first value. ### Claim 8 (depends on 7) The computer program product of claim 7, wherein the first value is 1. ### Claim 9 (depends on 7) The computer program product of claim 7, wherein the second value is 0.