# US 10,313,672 B2 · Entropy coding supporting mode switching > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,313,672 B2 - Document ID: US10313672B2 - Status: Granted - Kind: B2 - Application number: 16/037,914 - Filed: 2018-07-17 - Published: 2018-11-08 - Granted: 2019-06-04 - Earliest claimed: 2011-06-16 - Assignees: Ge Video Compression, LLC - Applicants: GE Video Compression, LLC - Inventors: Valeri George; Benjamin Bross; Heiner Kirchhoffer; Detlev Marpe; Tung Nguyen; Matthias Preiss; Mischa Siekmann; Jan Stegemann; Thomas Wiegand; Christian Bartnik - Web page: https://patentgrep.com/patent/US10313672B2 ## CPC - H04N 19/13: Adaptive entropy coding, e.g. adaptive variable length coding [AVLC] or context adaptive binary arithmetic coding [CABAC] - H03M 7/3064: {Segmenting} - H03M 7/42: using table look-up for the coding or decoding process, e.g. using read-only memory {(H03M7/4006 takes precedence)} - H04N 19/124: Quantisation - H04N 19/132: Sampling, masking or truncation of coding units, e.g. adaptive resampling, frame skipping, frame interpolation or high-frequency transform coefficient masking - H04N 19/174: the region being a slice, e.g. a line of blocks or a group of blocks - H04N 19/184: the unit being bits, e.g. of the compressed video stream - H04N 19/50: using predictive coding (H04N19/61 takes precedence) - H04N 19/513: Processing of motion vectors - H04N 19/52: by predictive encoding - H04N 19/61: in combination with predictive coding - H04N 19/70: characterised by syntax aspects related to video coding, e.g. related to compression standards - H04N 19/91: Entropy coding, e.g. variable length coding [VLC] or arithmetic coding - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - H03M: CODING; DECODING; CODE CONVERSION IN GENERAL (using fluidic means F15C4/00; optical analogue/digital converters G02F7/00; coding, decoding or code conversion, specially adapted for particular applications, see the relevant subclasses, e.g. G01D, G01R, G06F, G06T, G09G, G10L, G11B, G11C, H04B, H04L, H04M, H04N; ciphering or deciphering for cryptography or other purposes involving the need for secrecy G09C) ## Abstract A decoder for decoding a data stream into which media data is coded has a mode switch configured to activate a low-complexity mode or a high-efficiency mode depending on the data stream, an entropy decoding engine configured to retrieve each symbol of a sequence of symbols by entropy decoding using a selected one of a plurality of entropy decoding schemes, a desymbolizer configured to desymbolize the sequence of symbols to obtain a sequence of syntax elements, a reconstructor configured to reconstruct the media data based on the sequence of syntax elements, selection depending on the activated low-complexity mode or the high-efficiency mode. In another aspect, a desymbolizer is configured to perform desymbolization such that the control parameter varies in accordance with the data stream at a first rate in case of the high-efficiency mode being activated and the control parameter is constant irrespective of the data stream or changes depending on the data stream, but at a second lower rate in case of the low-complexity mode being activated. ## Claims ### Claim 1 A decoder for decoding a data stream including encoded data of a video, the decoder comprising: an entropy decoding engine configured to entropy decode data from the data stream using a selected one of a plurality of entropy decoding schemes to obtain a sequence of symbols, wherein each of the plurality of entropy decoding schemes involves arithmetic decoding of symbols, and the selection of the one of the plurality of entropy decoding schemes is in accordance with a low complexity mode or a high-efficiency mode, wherein, for at least one symbol of the sequence of symbols, the entropy decoding engine is configured to: select a context corresponding to the at least one symbol, the selected context corresponding to a probability model, and entropy decode the at least one symbol using the selected one of a plurality of entropy decoding schemes based on the selected context, wherein the probability model is updated at a first update rate under the high-efficiency mode and a second update rate lower than the first update rate under the low-complexity mode; a desymbolizer configured to desymbolize the sequence of symbols to obtain a sequence of syntax elements; and a reconstructor configured to reconstruct at least a portion of the video based on the sequence of syntax elements. ### Claim 2 (depends on 1) The decoder of claim 1, wherein the selection depends on previously retrieved symbols of the sequence of symbols in case of the high-efficiency mode being activated and independent from any previously retrieved symbols of the sequence of symbols in case of the low-complexity mode being activated. ### Claim 3 (depends on 1) The decoder of claim 1, wherein the data stream is structured into consecutive portions and each symbol of the sequence of symbols is associated with a respective one of a plurality of symbol types, wherein, for symbols of a predetermined symbol type within a current portion, the selection varies depending on previously retrieved symbols of the sequence of symbols of the predetermined symbol type within the current portion in case of the high-efficiency mode being activated, and is constant within the current portion in case of the low-complexity mode being activated. ### Claim 4 (depends on 1) The decoder of claim 1, wherein each symbol of the sequence of symbols is associated with a respective one of a plurality of symbol types, wherein for each symbol of a predetermined symbol type, the selection of the one of the plurality of entropy decoding schemes depends on a probability model associated with the predetermined symbol type. ### Claim 5 (depends on 1) The decoder of claim 1, wherein the probability model is associated with a probability state index having a first probability state accuracy for the high-efficiency mode, and a second probability state accuracy, lower than the first probability state accuracy, for the low-complexity mode. ### Claim 6 (depends on 1) The decoder of claim 1, wherein the data stream comprises information associated with color samples of the video. ### Claim 7 (depends on 1) The decoder of claim 1, wherein the data stream comprises information associated with a depth map of the video. ### Claim 8 An encoder for encoding data of a video into a data stream, the encoder comprising: a constructor configured to encode the data of the video into a sequence of syntax elements; a symbolizer configured to symbolize the sequence of syntax elements into a sequence of symbols; and an entropy encoding engine configured to encode each symbol of the sequence of symbols into the data stream using a selected one of a plurality of entropy encoding schemes, wherein each of the plurality of entropy decoding schemes involves arithmetic decoding of symbols, and the entropy encoding engine is configured to perform the selection of the one of the plurality of entropy encoding schemes in accordance with a low complexity mode or a high-efficiency mode, and wherein, for at least one symbol of the sequence of symbols, the entropy encoding engine is configured to: select a context corresponding to the at least one symbol, the selected context corresponding to a probability model, and entropy encode the at least one symbol using the selected one of a plurality of entropy encoding schemes based on the selected context, wherein the probability model is updated at a first update rate under the high-efficiency mode, and is updated at a second update rate lower than the first update rate under the low-complexity mode. ### Claim 9 (depends on 8) The encoder of claim 8, wherein the selection depends on previously retrieved symbols of the sequence of symbols in case of the high-efficiency mode being activated and independent from any previously retrieved symbols of the sequence of symbols in case of the low-complexity mode being activated. ### Claim 10 (depends on 8) The encoder of claim 8, wherein the data stream is structured into consecutive portions and each symbol of the sequence of symbols is associated with a respective one of a plurality of symbol types, wherein, for symbols of a predetermined symbol type within a current portion, the selection varies depending on previously retrieved symbols of the sequence of symbols of the predetermined symbol type within the current portion in case of the high-efficiency mode being activated, and is left constant within the current portion in case of the low-complexity mode being activated. ### Claim 11 (depends on 8) The encoder of claim 8, wherein each symbol of the sequence of symbols is associated with a respective one of a plurality of symbol types, wherein for each symbol of a predetermined symbol type, the selection of the one of the plurality of entropy decoding schemes depends on a probability model associated with the predetermined symbol type. ### Claim 12 (depends on 8) The encoder of claim 8, wherein the probability model is associated with a probability state index having a first probability state accuracy for the high-efficiency mode, and a second probability state accuracy, lower than the first probability state accuracy, for the low-complexity mode. ### Claim 13 (depends on 8) The encoder of claim 8, wherein the data stream comprises information associated with color samples of the video. ### Claim 14 (depends on 8) The encoder of claim 8, wherein the data stream comprises information associated with a depth map of the video. ### Claim 15 A method for decoding a data stream including encoded data of a video, the method comprising: entropy decoding data from the data stream using a selected one of a plurality of entropy decoding schemes to obtain a sequence of symbols, wherein each of the plurality of entropy decoding schemes involves arithmetic decoding of symbols, and the selection of the one of the plurality of entropy decoding schemes is in accordance with a low complexity mode or a high-efficiency mode, wherein, for at least one symbol of the sequence of symbols, the entropy decoding comprises: selecting a context corresponding to the at least one symbol, the selected context corresponding to a probability model, and entropy decoding the at least one symbol using the selected one of a plurality of entropy decoding schemes based on the selected context, wherein the probability model is updated at a first update rate under the high-efficiency mode, and is updated at a second update rate lower than the first update rate under the low-complexity mode; desymbolizing the sequence of symbols in order to acquire a sequence of syntax elements; and reconstructing at least a portion of the video based on the sequence of syntax elements. ### Claim 16 (depends on 15) The method of claim 15, wherein the selection depends on previously retrieved symbols of the sequence of symbols in case of the high-efficiency mode being activated and independent from any previously retrieved symbols of the sequence of symbols in case of the low-complexity mode being activated. ### Claim 17 (depends on 15) The method of claim 15, wherein the data stream is structured into consecutive portions and each symbol of the sequence of symbols is associated with a respective one of a plurality of symbol types, wherein, for symbols of a predetermined symbol type within a current portion, the selection varies depending on previously retrieved symbols of the sequence of symbols of the predetermined symbol type within the current portion in case of the high-efficiency mode being activated, and is constant within the current portion in case of the low-complexity mode being activated. ### Claim 18 (depends on 15) The method of claim 15, wherein each symbol of the sequence of symbols is associated with a respective one of a plurality of symbol types, wherein for each symbol of a predetermined symbol type, the selection of the one of the plurality of entropy decoding schemes depends on a probability model associated with the predetermined symbol type. ### Claim 19 (depends on 15) The method of claim 15, wherein the probability model is associated with a probability state index having a first probability state accuracy for the high-efficiency mode, and a second probability state accuracy, lower than the first probability state accuracy, for the low-complexity mode. ### Claim 20 (depends on 15) The method of claim 15, wherein the data stream comprises information associated with color samples of the video. ### Claim 21 (depends on 15) The method of claim 15, wherein the data stream comprises information associated with a depth map of the video. ### Claim 22 A non-transitory computer-readable medium for storing data associated with a video, comprising: a data stream stored in the non-transitory computer-readable medium, the data stream comprising an encoded sequence of symbols of a video, wherein the sequence of symbols is encoded into the data stream based on a plurality of operations comprising: encoding the data of the video into a sequence of syntax elements; symbolizing the sequence of syntax elements into a sequence of symbols; and entropy encoding each symbol of the sequence of symbols into the data stream using a selected one of a plurality of entropy encoding schemes, wherein each of the plurality of entropy decoding schemes involves arithmetic decoding of symbols, and the selection of the one of the plurality of entropy encoding schemes is performed in accordance with a low complexity mode or a high-efficiency mode, and wherein, for at least one symbol of the sequence of symbols, the entropy encoding comprises: selecting a context corresponding to the at least one symbol, the selected context corresponding to a probability model, and entropy encoding the at least one symbol using the selected one of a plurality of entropy encoding schemes based on the selected context, wherein the probability model is updated at a first update rate under the high-efficiency mode, and is updated at a second update rate lower than the first update rate under the low-complexity mode. ### Claim 23 (depends on 22) The non-transitory computer-readable medium of claim 22, wherein the data stream comprises information associated with color samples of the video. ### Claim 24 (depends on 22) The non-transitory computer-readable medium of claim 22, wherein the data stream comprises information associated with a depth map of the video. ### Claim 25 (depends on 22) The non-transitory computer-readable medium of claim 22, wherein the selection depends on previously retrieved symbols of the sequence of symbols in case of the high-efficiency mode being activated and independent from any previously retrieved symbols of the sequence of symbols in case of the low-complexity mode being activated. ### Claim 26 (depends on 22) The non-transitory computer-readable medium of claim 22, wherein the data stream is structured into consecutive portions and each symbol of the sequence of symbols is associated with a respective one of a plurality of symbol types, wherein, for symbols of a predetermined symbol type within a current portion, the selection varies depending on previously retrieved symbols of the sequence of symbols of the predetermined symbol type within the current portion in case of the high-efficiency mode being activated, and is constant within the current portion in case of the low-complexity mode being activated. ### Claim 27 (depends on 22) The non-transitory computer-readable medium of claim 22, wherein each symbol of the sequence of symbols is associated with a respective one of a plurality of symbol types, wherein for each symbol of a predetermined symbol type, the selection of the one of the plurality of entropy decoding schemes depends on a probability model associated with the predetermined symbol type. ### Claim 28 (depends on 22) The non-transitory computer-readable medium of claim 22, wherein the probability model is associated with a probability state index having a first probability state accuracy for the high-efficiency mode, and a second probability state accuracy, lower than the first probability state accuracy, for the low-complexity mode. ### Claim 29 (depends on 15) A non-transitory computer-readable medium comprising a computer program for performing, when running on a computer, a method of claim 15. ### Claim 30 (depends on 29) The non-transitory computer-readable medium of claim 29, wherein the data stream comprises information associated with color samples of the video.