Scalable coding of video sequences using tone mapping and different color gamuts
A Scalable Video Coding (SVC) process for scalable video coding takes into account color gamut primaries along with spatial resolution. The process for re-sampling uses video color data obtained from an encoder or decoder process of a base layer (BL) in a multi-layer system to enable improved encoding and decoding in an enhancement layer (EL) or higher layers taking into account color conversion between layers. Examples of applicable SVC include MPEG-4 and High Efficiency Video Coding (HEVC). With the SVC process, video data expressed in one color gamut space can be used for prediction in encoding with a different color space.
1. A method of decoding multi-layer video data from a bitstream comprising a plurality of layers of video data, the method comprising:
(a) receiving samples within said bitstream of a base layer comprising a plurality of frames, each said frame having a first spatial resolution;
(b) receiving samples within said bitstream of an enhancement layer comprising said plurality of frames, each frame having a second spatial resolution, wherein said first spatial resolution is different than said second spatial resolution;
(c) receiving a first tone mapping information associated with said base layer, where said first tone mapping information includes different tone mapping information for different locality within said base layer;
(d) receiving a second tone mapping information associated with said enhancement layer, wherein said first tone mapping information is different than said second tone mapping information, where said second tone mapping information includes different tone mapping information for different locality within said enhancement layer;
(e) receiving a base order signal within said bitstream indicating an order by which a prediction for an output set of frames for which of ( 1 ) a spatial scaling or ( 2 ) said first tone mapping information is applied first to said base layer;
(f) receiving an enhancement order signal within said bitstream indicating an order by which a prediction for said output set of frames for which of ( 1 ) a spatial scaling or ( 2 ) said second tone mapping information is applied first to said enhancement layer;
(g) determining an output set of frames based upon ( 1 ) said base layer together with said first tone mapping information further based upon said base order signal, and ( 2 ) said enhancement layer together with said second tone mapping information further based upon said enhancement order signal.
2. The method of claim 1 wherein said first spatial resolution has a lower resolution than said second spatial resolution.
3. The method of claim 2 further comprising receiving cross layer information within said bitstream interrelating said base layer and said enhancement layer for said determining said output set of frames.
4. The method of claim 3 further comprising upsampling said base layer from said first spatial resolution to said second spatial resolution.
5. The method of claim 4 wherein output set of frames has an output tone map different from at least one of said first tone mapping information and said second tone mapping information.