Hierarchical inter-layer prediction in multi-loop scalable video coding
A method for encoding a video sequence in a scalable video encoder to generate a scalable bitstream is provided that includes encoding the video sequence in a first layer encoder of the scalable video encoder to generate a first sub-bitstream, encoding the video sequence in a second layer encoder of the scalable video encoder to generate a second sub-bitstream, wherein portions of the video sequence being encoded in the second layer encoder are predicted using reference portions of the video sequence encoded in the first layer encoder, combining the first sub-bitstream and the second sub-bitstream in the scalable bitstream, and signaling an indication of a highest temporal level of the first sub-bitstream comprising at least one of the reference portions in the scalable bitstream.
1. A method for encoding a video sequence in a scalable video encoder to generate a scalable bitstream, the method comprising:
encoding the video sequence in a first layer encoder of the scalable video encoder to generate a first layer sub-bitstream that includes a first temporal hierarchy;
encoding the video sequence in a second layer encoder of the scalable video encoder to generate a second layer sub-bitstream that includes a second temporal hierarchy, wherein portions of the video sequence being encoded in the second layer encoder are predicted using reference portions of the video sequence encoded in the first layer encoder;
combining the first layer sub-bitstream and the second layer sub-bitstream in the scalable bitstream.
2. The method of claim 1 , further comprising signaling an indication of a temporal level in the first temporal hierarchy of the first layer sub-bitstream that is used for inter-layer prediction in the scalable bitstream.
3. The method of claim 2 , wherein the indication of the temporal level is signaled in a video parameter set.
4. The method of claim 1 , wherein the first layer encoder is a base layer encoder of the scalable video encoder.
5. The method of claim 1 , wherein the first layer encoder is an enhancement layer encoder of the scalable video encoder.
6. The method of claim 1 , further comprising:
signaling in the scalable bitstream an indication of a maximum decoded picture buffer (DPB) size needed for decoding the second layer sub-bitstream and the first layer sub-bitstream when the second layer sub-bitstream is a target sub-bitstream for decoding.
7. The method of claim 6 , wherein the indication of a maximum DPB size comprises an indication of a maximum DPB size needed for decoding the first layer sub-bitstream as a reference sub-bitstream.