Source color volume information messaging
Methods are described to communicate source color volume information in a coded bitstream using SEI messaging. Such data include at least the minimum, maximum, and average luminance values in the source data plus optional data that may include the color volume x and y chromaticity coordinates for the input color primaries (e.g., red, green, and blue) of the source data, and the color x and y chromaticity coordinates for the color primaries corresponding to the minimum, average, and maximum luminance values in the source data. Messaging data signaling an active region in each picture may also be included.
1. A non-transitory medium storing one or more processor-executable instructions that, when executed by the processor, causes the processor to process a video bitstream comprising one or more coded pictures and source color volume metadata to extract information about the source color volume of the video bitstream for generating an output video signal, wherein the metadata comprises:
a source color volume cancel flag, which when set to 1 indicates that the source color volume metadata cancels any persistence of previous source color volume metadata,
source color x and y chromaticity coordinates for one or more color primary components, wherein for a color primary component c of the video bitstream, the source color x and y chromaticity coordinates define, respectively, its normalized x and y chromaticity coordinates, and
a minimum, a maximum, and an average luminance value specifying, respectively, minimum, maximum, and average luminance values of pixel values in the video bitstream.
2. The non-transitory medium of claim 1 , wherein the x and y chromaticity coordinates are specified in increments of 0.00002, according to the CIE 1931 definition of x and y as specified in ISO 11664-1.
3. The non-transitory medium of claim 1 , wherein for describing color volumes that use red, green, and blue color primaries, c=0 corresponds to the green color primary, c=1 corresponds to the blue color primary, and c=2 corresponds to the red color primary.
4. The non-transitory medium of claim 1 , wherein the minimum, the maximum, and the average luminance value are specified in units of 0.0001 candelas per square meter (nits).
5. An apparatus to extract source color volume information, the apparatus comprising:
an input and memory to receive a coded bitstream including a video bitstream and source color volume metadata;
a processor to extract, from the coded bitstream, the video bitstream and the source color volume metadata, wherein the metadata comprise:
a source color volume cancel flag, which when set to 1 indicates that the source color volume metadata cancels any persistence of previous source color volume metadata,
source color x and y chromaticity coordinates for one or more color primary components, wherein for a color primary component c of the video bitstream, the source color x and y chromaticity coordinates define, respectively, its normalized x and y chromaticity coordinates, and
a minimum, a maximum, and an average luminance value specifying, respectively, minimum, maximum, and average luminance values of pixel values in the video bitstream; and
an output to transmit the extracted video bitstream and the extracted source color volume metadata for generating an output video signal.
6. The apparatus of claim 5 , wherein the output video signal is generated based on the extracted video bitstream, the x and y chromaticity coordinates for the one or more color primary components, and the minimum, the maximum, and the average luminance values.
7. The apparatus of claim 5 , wherein the x and y chromaticity coordinates are specified in increments of 0.00002, according to the CIE 1931 definition of x and y as specified in ISO 11664-1.
8. The apparatus of claim 5 , wherein for describing color volumes that use red, green, and blue color primaries, c=0 corresponds to the green color primary, c=1 corresponds to the blue color primary, and c=2 corresponds to the red color primary.
9. The apparatus of claim 5 , wherein the minimum, the maximum, and the average luminance value are specified in units of 0.0001 candelas per square meter (nits).
10. An apparatus comprising:
an input and memory to receive a video bitstream and source color volume metadata, wherein the metadata comprise:
a source color volume cancel flag, which when set to 1 indicates that the source color volume metadata cancels any persistence of previous source color volume metadata,
source color x and y chromaticity coordinates for one or more color primary components, wherein for a color primary component c of the video bitstream, the source color x and y chromaticity coordinates define, respectively, its normalized x and y chromaticity coordinates, and
a minimum, a maximum, and an average luminance value specifying, respectively, minimum, maximum, and average luminance values of pixel values in the video bitstream;
a processor to generate a coded bitstream based on the video bitstream and the metadata; and
an output to transmit the coded bitstream.
11. The apparatus of claim 10 , wherein the x and y chromaticity coordinates are specified in increments of 0.00002, according to the CIE 1931 definition of x and y as specified in ISO 11664-1.
12. The apparatus of claim 10 , wherein for describing color volumes that use red, green, and blue color primaries, c=0 corresponds to the green color primary, c=1 corresponds to the blue color primary, and c=2 corresponds to the red color primary.
13. The apparatus of claim 10 , wherein the minimum, the maximum, and the average luminance value are specified in units of 0.0001 candelas per square meter (nits).