Multi-compatible low and high dynamic range and high bit-depth texture and video encoding systems
A method of processing image data includes generating image data including luminance and chrominance data representing a selected object, separating the luminance and chrominance data, storing the separated luminance and chrominance data in corresponding separate spaces in memory, and separately compressing the stored luminance and chrominance data.
1. A method of processing high dynamic range video or images comprising:
generating a high dynamic range video or image;
separating the high dynamic range data for the video or image into separated grayscale and color video or image component data;
storing the separated grayscale and color video or image component data in corresponding separate memory spaces;
compressing the separately stored color video or image component data;
clamping or converting tonal values of the separately stored grayscale video or image component data of the high dynamic range image to generate a grayscale low dynamic range component data;
dividing values of the grayscale low dynamic range component data by values of the grayscale high dynamic range component data to obtain fractional component data;
compressing the fractional component data; and
compressing the grayscale low dynamic range video or image component data.
2. The method of claim 1 , wherein compressing the grayscale low dynamic range component data comprises value scaling and gamma correcting the grayscale low dynamic range component data, and compressing the value scaled and gamma corrected grayscale low dynamic range component data.
3. The method of claim 1 , wherein compressing the fractional component data comprises value scaling and gamma correcting the fractional component data, and compressing the value scaled and gamma corrected fractional component data.
4. A method to decode image or video data processed according to claim 1 , comprising:
decompressing the compressed fractional component data to produce fractional luminance data;
decompressing the compressed grayscale low dynamic range video or image component data to produce low dynamic range luminance video or image data;
decompressing the compressed separately stored color video or image component data to produce high dynamic range chrominance video or image data;
recovering high dynamic range luminance video or image component data by multiplying the low dynamic range luminance video or image data for the fractional luminance data; and
combining high dynamic range luminance video or image component data and the high dynamic range chrominance video or image data to obtain high dynamic range video or image component data.
5. The method of claim 4 , wherein decompressing the compressed grayscale low dynamic range component data comprises decompressing grayscale low dynamic range component data and value re-scaling and inverse gamma correcting the decompressed grayscale low dynamic range component data.
6. The method of claim 4 , wherein decompressing the fractional component data comprises decompressing the fractional component data and value re-scaling, and inverse gamma correcting the decompressed fractional component data.