ADAPTIVE RESOLUTION MANAGEMENT USING SUB-FRAMES
A video encoder encodes a bitstream for decoding by a compliant decoder which is configured to selectively operate in a mode for generating a motion compensation predictor from a reference picture for a subsequent picture having a resolution different from the reference picture. The encoded bitstream includes a coded picture having a first coded region and a second coded region and signaling information from which the decoder determines first and second spatial resolution scale factors for reconstructing the first and second regions.
1 . A video encoder configured to:
encode a bitstream to be decoded by a decoder, the decoder being configured to:
selectively operate in a mode for generating a motion compensation predictor from a reference picture for a subsequent picture having a resolution different from the reference picture, the mode utilizing a spatial resolution changing scale factor and a filter;
receive a bit stream including a coded picture and signaling information, the coded picture including a first coded region and second coded region, the signaling information including first information for determining a first spatial resolution changing scale factor and second information useful for determining a second spatial resolution changing scale factor;
determine, using the first information, the first spatial resolution changing scale factor, the first scale factor being associated with the first region;
determine using the second information, the second spatial resolution changing scale factor, the second scale factor being associated with the second region, the first and second scale factors having different values; and
reconstruct the pixel values of the coded picture using the mode with the first spatial resolution changing scale factor to form a first motion compensation predictor to decode the first region and using the mode with the second spatial resolution changing scale factor to form a second motion compensation predictor to decode the second region.
2 . The encoder of claim 1 wherein the first region is a first slice of the picture and the second region is a second slice of the picture.
3 . The encoder of claim 1 wherein the first region is a first sub-picture and the second region is a second sub-picture.
4 . The encoder of claim 1 wherein the first region and the second region comprise the entire picture.
5 . The encoder of claim 1 wherein the first and second scale factors are both horizontal scale factors.
6 . The encoder of claim 1 wherein the first and second scale factors are both vertical scale factors.
7 . The encoder of claim 1 wherein the first region includes a first coding unit and the second region includes a second coding unit.
8 . The encoder of claim 7 wherein the first coding unit is N×N and N is one of 16, 32, 64, 128, and the second coding unit is M×M and M is one of 16, 32, 64, 128.