Method for encoding and method for decoding a LUT and corresponding devices

A non-transitory machine readable medium storing executable instructions which when executed by a data processing system cause the data processing system to perform a method for encoding data, the method comprising:

• determining whether to set a flag to a value to indicate that a data payload contains color primaries input data, the data payload for use at a device that receives the data payload and a stream of images to be displayed by the device;
• encoding, when the flag is set to the value, the color primaries input data into the data payload, and wherein the color primaries input data specify chromaticity coordinates of source primaries in a color space, and wherein the data payload is a supplemental enhancement information for use by the device to map color values of the images for customization to a display device used by the device to display images on the display device, and wherein the encoding comprises:
• storing the color primaries input data in the data payload, and wherein the data payload further comprises a 3-dimensional (3-D) look up table for use in performing a color mapping function, the 3-D look up table having a lattice of vertices each of which is associated with a color value, and wherein the 3-D look up table is encoded by encoding a current octant by predicting at least one value of a vertex in the current octant from another value to obtain a prediction and encoding a residue computed between the at least one value of the vertex and the prediction.

A method for decoding data, the method comprising:

• receiving, by a device, a data structure describing a stream of images received by the device;
• determining whether the data structure contains a data payload that contains color primaries input data, the color primaries input data for use at the device to process the images in order to display the images on a display device coupled to the device;
• decoding the data structure to use the color primaries input data to display the images, and wherein the color primaries input data specify chromaticity coordinates of source primaries in a color space;
• receiving the stream of images that are described by the data structure;
• and
• wherein the device determines the data structure contains the color primaries input data based on a value of a flag in the data payload, and wherein the data payload is a supplemental enhancement information for use by the device to map color values of the images for customization to a display device used by the device to display the images on the device, and wherein the data payload further comprises a 3-dimensional (3-D) look up table for use in performing a color mapping function, the 3-D look up table having a lattice of vertices each of which is associated with a color value, and wherein the 3-D look up table is encoded by encoding a current octant by predicting at least one value of a vertex in the current octant from another value to obtain a prediction and encoding a residue computed between the at least one value of the vertex and the prediction.