Grouping palette bypass bins for video coding

Patent metadata

Field	Value
Publication number	US-11146788-B2
Application number	US-201615177201-A
Country	US
Kind code	B2
Filing date	Jun 8, 2016
Priority date	Jun 12, 2015
Publication date	Oct 12, 2021
Grant date	Oct 12, 2021

Abstract

An example method of coding video data includes coding, from a coded video bitstream, a syntax element that indicates whether a transpose process is applied to palette indices of a palette for a current block of video data; decoding, from the coded video bitstream and at a position in the coded video bitstream that is after the syntax element that indicates whether the transpose process is applied to palette indices of the palette for the current block of video data, one or more syntax elements related to delta quantization parameter (QP) and/or chroma QP offsets for the current block of video data; and decoding the current block of video data based on the palette for the current block of video data and the one or more syntax elements related to delta QP and/or chroma QP offsets for the current block of video data.

First claim

What is claimed is:

1. A method of decoding video data, the method comprising:
decoding, in accordance with a syntax table that specifies a parsing order for a coded video bitstream and using context adaptive binary arithmetic coding (CABAC) with a context, a syntax element from the coded video bitstream that indicates whether a transpose process is applied to palette indices of a current palette for a current block of video data;
decoding, in accordance with the syntax table and from the coded video bitstream and using CABAC with a context, one or more syntax elements related to delta quantization parameter (QP) and/or chroma QP offsets for the current block of video data, wherein the syntax table specifies that the one or more syntax elements related to delta quantization parameter (QP) and/or chroma QP offsets for the current block of video data are parsed after the syntax element that indicates whether the transpose process is applied to palette indices of the current palette for the current block of video data;
decoding, in accordance with the syntax table and from the coded video bitstream, a group of syntax elements using Bypass mode, wherein the group of syntax elements comprises:
one or more syntax elements that indicate a number of zeros that precede a non-zero entry in an array that indicates whether entries from a predictor palette are reused in the current palette;
a syntax element that indicates a number of entries in the current palette that are explicitly signalled;
one or more syntax elements that each indicate a value of a component in an entry in the current palette;
a syntax element that indicates whether the current block of video data includes at least one escape coded sample;
a syntax element that indicates a number of indices in the current palette that are explicitly signalled or inferred; and
one or more syntax elements that indicate indices in an array of entries of the current palette; and

decoding the current block of video data based on the current palette for the current block of video data, the group of syntax elements, and the one or more syntax elements related to delta QP and/or chroma QP offsets for the current block of video data.

2. The method of claim 1 , wherein the syntax element that indicates whether the transpose process is applied to palette indices of the current palette of the current block of video data comprises a palette_transpose_flag syntax element.

3. The method of claim 1 , wherein the one or more syntax elements related to delta QP comprise one or both of a syntax element that indicates an absolute value of a difference between a QP of the current block and a predictor of the QP of the current block and a syntax element that indicates a sign of the difference between the QP of the current block and the predictor of the QP of the current block.

4. The method of claim 1 , wherein the one or more syntax elements related to chroma QP offsets comprise one or both of a syntax element that indicates whether entries in one or more offset lists are added to a luma QP of the current block to determine chroma QPs for the current block and a syntax element that indicates an index of an entry in each of the one or more offset lists that are added to the luma QP for the current block to determine the chroma QPs for the current block.

5. The method of claim 1 , wherein one or more of:
the one or more syntax elements that indicate a number of zeros that precede a non-zero entry in an array that indicates whether entries from a predictor palette are reused in the current palette comprise one or more palette_predictor_run syntax elements,
the syntax element that indicates a number of entries in the current palette that are explicitly signalled comprises a num_signalled_palette_entries syntax element,
the one or more syntax elements that each indicate a value of a component in an entry in the current palette comprise one or more palette_entry syntax elements,
the syntax element that indicates whether the current block of video data includes at least one escape coded sample comprises palette_escape_val_present_flag,
the syntax element that indicates a number of indices in the current palette that are explicitly signalled or inferred comprise a num_palette_indices_idc syntax element, and
the one or more syntax elements that indicate indices in an array of entries of the current palette comprise one or more palette_index_idc syntax elements.

6. The method of claim 1 , wherein the syntax table specifies that the group of syntax elements are parsed from the coded video bitstream before the syntax element that indicates whether the transpose process is applied to palette indices of the current palette of the current block of video data.

7. The method of claim 1 , further comprising:
decoding, in accordance with the syntax table and from the coded video bitstream, a syntax element that indicates a last occurrence of a run type flag within the current block of video data, wherein the syntax table specifies that the syntax element that indicates the last occurrence of the run type flag within the current block of video data is parsed after the group of syntax elements coded using Bypass mode.

8. The method of claim 7 , wherein decoding the syntax element that indicates the last occurrence of a run type flag within the current block of video data comprises decoding the syntax element that indicates the last occurrence of a run type flag within the current block of video data using context adaptive binary arithmetic coding (CABAC) with a context.

9. A method of encoding video data, the method comprising:
encoding, in accordance with a syntax table that specifies a coding order for a coded video bitstream and using context adaptive binary arithmetic coding (CABAC) with a context, a syntax element in the coded video bitstream that indicates whether a transpose process is applied to palette indices of a current palette for a current block of video data;
encoding, in accordance with the syntax table and in the coded video bitstream, one or more syntax elements related to delta quantization parameter (QP) and/or chroma QP offsets for the current block of video data, wherein the syntax table specifies that the one or more syntax elements related to delta quantization parameter (QP) and/or chroma QP offsets for the current block of video data are encoded after the syntax element that indicates whether the transpose process is applied to palette indices of the current palette for the current block of video data;
encoding, in accordance with the syntax table and in the coded video bitstream, a group of syntax elements using Bypass mode, wherein the group of syntax elements comprises:
one or more syntax elements that indicate a number of zeros that precede a non-zero entry in an array that indicates whether entries from a predictor palette are reused in the current palette;
a syntax element that indicates a number of entries in the current palette that are explicitly signalled;
one or more syntax elements that each indicate a value of a component in an entry in the current palette;
a syntax element that indicates whether the current block of video data includes at least one escape coded sample;
a syntax element that indicates a number of indices in the current palette that are explicitly signalled or inferred; and
one or more syntax elements that indicate indices in an array of entries of the current palette; and

encoding the current block of video data based on the current palette for the current block of video data, the group of syntax elements, and the one or more syntax elements related to delta QP and/or chroma QP offsets for the current block of video data.

10. The method

Assignees

• Qualcomm Inc

Inventors

• Joshi Rajan Laxman
• Seregin Vadim
• Pu Wei
• Zou Feng
• Karczewicz Marta

Classifications

• H04N19/184

  the unit being bits, e.g. of the compressed video stream · CPC title

• H04N19/13 Primary

  Adaptive entropy coding, e.g. adaptive variable length coding [AVLC] or context adaptive binary arithmetic coding [CABAC] · CPC title

• H04N19/91

  Entropy coding, e.g. variable length coding [VLC] or arithmetic coding · CPC title

• H04N19/93

  Run-length coding · CPC title

• H04N19/186

  the unit being a colour or a chrominance component · CPC title