# US 2020/0288170 A1 · Methods of escape pixel coding in index map coding > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0288170 A1 - Document ID: US20200288170A1 - Status: Published application - Kind: A1 - Application number: 16/880,652 - Filed: 2020-05-21 - Published: 2020-09-10 - Earliest claimed: 2014-11-12 - Assignees: Hfi Innovation Inc. - Applicants: Hfi Innovation Inc. - Inventors: Tzu-Der CHUANG; Ching-Yeh CHEN; Yu-Chen SUN; Jing YE; Shan LIU; Xiaozhong XU; Jungsun KIM - Web page: https://patentgrep.com/patent/US20200288170A1 ## CPC - H04N 19/593: involving spatial prediction techniques - 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 19/426: using memory downsizing methods - H04N 19/44: Decoders specially adapted therefor, e.g. video decoders which are asymmetric with respect to the encoder - H04N 19/463: by compressing encoding parameters before transmission - H04N 19/70: characterised by syntax aspects related to video coding, e.g. related to compression standards - H04N 19/93: Run-length coding - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract A method of video coding with reduced implementation cost by reusing transform coefficient buffer palette for palette coding is disclosed. If the current prediction mode is an Intra prediction mode or the Inter prediction mode, information related to transform coefficients for prediction residual of the current block resulted from Intra prediction or Inter prediction is stored in the transform coefficient buffer. If the current prediction mode is the palette coding mode, information related to palette data associated with the current block is stored in the transform coefficient buffer. The current block is then encoded or decoded based on the information related to the transform coefficients if the current block is coded in the Intra prediction mode or the Inter prediction mode, or the information related to the palette data stored in the transform coefficient buffer if the current prediction mode is the palette coding mode. ## Claims ### Claim 1 A method of video decoding, comprising: receiving a bitstream carrying coded data of a current block; determining a current prediction mode for the current block; in a case that the current prediction mode for the current block is determined to be a palette coding mode, obtaining all escape samples for the current block from the coded data, components of different colors of the escape samples being separately grouped by color in the coded data; and decoding the current block according to the palette coding mode using information including the escape samples. ### Claim 2 (depends on 1) The method of claim 1, wherein the escape samples for the current block are signaled at an end of coded palette data for the current block. ### Claim 3 (depends on 2) The method of claim 2, wherein the coded palette data includes the escape samples and parameter specifying one or more of a palette run type, a palette index, a palette run, escape flags, and a palette table associated with the current block. ### Claim 4 (depends on 1) The method of claim 1, wherein the obtaining all the escape samples for the current block from the coded data comprises: obtaining first components of a first color of the escape samples from a first group of data in the coded data; and obtaining second components of a second color of the escape samples from a second group of data in the coded data, the second group of data being arranged after the first group of data in the coded data. ### Claim 5 A method of video encoding, comprising: determining a current prediction mode for encoding a current block; in a case that the current prediction mode for encoding the current block is determined to be a palette coding mode, determining escape samples for the current block, generating coded data by encoding the current block according to the palette coding mode using information including the escape samples, and arranging all the escape samples for the current block in the coded data, components of different colors of the escape samples being separately grouped by color in the coded data; and generating a bitstream carrying the coded data. ### Claim 6 (depends on 5) The method of claim 5, wherein the escape samples for the current block are signaled at an end of coded palette data for the current block. ### Claim 7 (depends on 6) The method of claim 6, wherein the coded palette data includes the escape samples and parameter specifying one or more of a palette run type, a palette index, a palette run, escape flags, and a palette table associated with the current block. ### Claim 8 (depends on 5) The method of claim 5, wherein the arranging all the escape samples for the current block in the coded data comprises: arranging first components of a first color of the escape samples as a first group of data in the coded data; and arranging second components of a second color of the escape samples as a second group of data in the coded data, the second group of data being arranged after the first group of data in the coded data. ### Claim 9 An apparatus for video decoding, comprising: processing circuitry configured to receive a bitstream carrying coded data of a current block; determine a current prediction mode for the current block; in a case that the current prediction mode for the current block is determined to be a palette coding mode, obtain all escape samples for the current block from the coded data, components of different colors of the escape samples being separately grouped by color in the coded data; and decode the current block according to the palette coding mode using information including the escape samples. ### Claim 10 (depends on 9) The apparatus of claim 9, wherein the escape samples for the current block are signaled at an end of coded palette data for the current block. ### Claim 11 (depends on 10) The apparatus of claim 10, wherein the coded palette data includes the escape samples and parameter specifying one or more of a palette run type, a palette index, a palette run, escape flags, and a palette table associated with the current block. ### Claim 12 (depends on 9) The apparatus of claim 9, wherein the processing circuitry is further configured to: obtain first components of a first color of the escape samples from a first group of data in the coded data; and obtain second components of a second color of the escape samples from a second group of data in the coded data, the second group of data being arranged after the first group of data in the coded data.