# US 12,604,043 B2 · Sample adaptive offset (SAO) parameter signaling > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,604,043 B2 - Document ID: US12604043B2 - Status: Granted - Kind: B2 - Application number: 18/660,921 - Filed: 2024-05-10 - Published: 2024-09-05 - Granted: 2026-04-14 - Earliest claimed: 2012-02-27 - Assignees: Texas Instruments Incorporated - Applicants: Texas Instruments Incorporated - Inventors: Woo-Shik Kim; Do-Kyoung Kwon; Minhua Zhou - Web page: https://patentgrep.com/patent/US12604043B2 ## CPC - H04N 19/86: involving reduction of coding artifacts, e.g. of blockiness - H04N 19/117: Filters, e.g. for pre-processing or post-processing (sub-band filter banks H04N19/635) - H04N 19/186: the unit being a colour or a chrominance component - 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 19/80: Details of filtering operations specially adapted for video compression, e.g. for pixel interpolation (H04N19/635, H04N19/86 take precedence) - H04N 19/82: involving filtering within a prediction loop - H04N 19/91: Entropy coding, e.g. variable length coding [VLC] or arithmetic coding - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract Techniques for signaling of sample adaptive offset (SAO) information that may reduce the coding rate for signaling such information in the compressed bit stream are provided. More specifically, techniques are provided that allow SAO information common to two or more of the color components to be signaled using one or more syntax elements (flags or indicators) representative of the common information. These techniques reduce the need to signal SAO information separately for each color component. ## Claims ### Claim 1 A system comprising: a receiver configurable to receive a bit stream; and a decoder coupled to the receiver and configurable to: decode a first flag in the bit stream, wherein the first flag indicates that edge offset sample adaptive offset (SAO) filtering of a luma component is not applied, and wherein the first flag indicates that band offset SAO filtering of the luma component is not applied; decode a second flag in the bit stream, wherein the second flag indicates that edge offset SAO filtering of a chroma component is applied; and apply edge offset SAO filtering to the chroma component based on the second flag. ### Claim 2 (depends on 1) The system of claim 1, wherein the first flag indicates that the SAO filtering of the luma component is not applied in a current largest coding unit (LCU), and wherein the second flag indicates that the edge offset SAO filtering of the chroma component can be applied in the current LCU. ### Claim 3 (depends on 1) The system of claim 1, wherein the chroma component is a first chroma component, wherein the decoder is configurable to decode a combined flag in the bit stream, and wherein the combined flag indicates that the first chroma component and a second chroma component share SAO parameters. ### Claim 4 (depends on 1) The system of claim 1, wherein the decoder is configurable to decode the second flag after decoding the first flag. ### Claim 5 (depends on 1) The system of claim 1, wherein the decoder is configurable to apply the edge offset SAO filtering to the chroma component to generate a reconstructed image, and wherein the system further comprises a light emitting diode display configured to display the reconstructed image. ### Claim 6 (depends on 1) The system of claim 1, wherein the decoder is configurable to apply the edge offset SAO filtering to the chroma component to generate a reconstructed image, and wherein the system further comprises a liquid crystal display configured to display the reconstructed image. ### Claim 7 (depends on 1) The system of claim 1, wherein the decoder is configurable to: apply a deblocking filter to the luma component; and apply the edge offset SAO filtering to the chroma component after applying the deblocking filter. ### Claim 8 (depends on 1) The system of claim 1, wherein the decoder is configurable to: decode a merge flag in the bit stream; decode the first flag only if the merge flag is not set; and decode the second flag only if the merge flag is not set. ### Claim 9 A system comprising: a frame buffer; and a decoder coupled to the frame buffer and configurable to: decode a first flag in a bit stream, wherein the first flag indicates that edge offset sample adaptive offset (SAO) filtering is not used for a luma component, and wherein the first flag indicates that band offset SAO filtering is not used for the luma component; decode a second flag in the bit stream, wherein the second flag indicates that edge offset SAO filtering is used for a chroma component; apply edge offset SAO filtering to the chroma component based on the second flag to generate a picture; and store the picture in the frame buffer. ### Claim 10 (depends on 9) The system of claim 9, wherein the first flag indicates that the SAO filtering is not used for the luma component in a current slice, and wherein the second flag indicates that the edge offset SAO filtering is used for the chroma component in the current slice. ### Claim 11 (depends on 9) The system of claim 9, wherein the chroma component is a first chroma component, wherein the decoder is configurable to decode a combined flag in the bit stream, and wherein the combined flag indicates that the first chroma component and a second chroma component share SAO parameters. ### Claim 12 (depends on 9) The system of claim 9, wherein the decoder is configurable to decode the second flag after decoding the first flag. ### Claim 13 (depends on 9) The system of claim 9, wherein the decoder is configurable to apply the edge offset SAO filtering to the chroma component to generate a reconstructed image, and wherein the system further comprises a light emitting diode display configured to display the reconstructed image. ### Claim 14 (depends on 9) The system of claim 9, wherein the decoder is configurable to apply the edge offset SAO filtering to the chroma component to generate a reconstructed image, and wherein the system further comprises a liquid crystal display configured to display the reconstructed image. ### Claim 15 (depends on 9) The system of claim 9, wherein the decoder is configurable to: decode a merge flag in the bit stream; decode the first flag only if the merge flag is not set; and decode the second flag only if the merge flag is not set. ### Claim 16 A method comprising: receiving a bit stream; decoding a first flag in the bit stream, wherein the first flag indicates that edge offset sample adaptive offset (SAO) filtering of a luma component is not applied, and wherein the first flag indicates that band offset SAO filtering is not used for the luma component; decoding a second flag in the bit stream, wherein the second flag indicates that edge offset SAO filtering of a chroma component is applied; and applying edge offset SAO filtering to the chroma component based on the second flag. ### Claim 17 (depends on 16) The method of claim 16, wherein the chroma component is a first chroma component, wherein the method further comprises decoding a combined flag in the bit stream, and wherein the combined flag indicates that the first chroma component and a second chroma component share SAO parameters. ### Claim 18 (depends on 16) The method of claim 16, wherein decoding the second flag occurs after decoding the first flag. ### Claim 19 (depends on 16) The method of claim 16, further comprising: generating a reconstructed image by at least applying the edge offset SAO filtering to the chroma component; and displaying the reconstructed image by a light emitting diode display. ### Claim 20 (depends on 16) The method of claim 16, further comprising: generating a reconstructed image by at least applying the edge offset SAO filtering to the chroma component; and displaying the reconstructed image by a liquid crystal display.