Signaling of global motion vector in picture header
A decoder includes circuitry configured to receive a bitstream, extract a header, determine, using the header, a global motion model, and decode a current block of a current frame using the global motion model. Related apparatus, systems, techniques and articles are also described.
1. A decoder, the decoder comprising circuitry configured to:
receive a bitstream including a current coded block of a current picture;
detect a header for the current coded block in the bitstream;
determine, using the header, a global motion model for the current block, the global motion model being one of translational motion, 4-parameter affine motion, or 6-parameter affine motion, wherein parameters for the determined global motion model are not explicitly signaled in the bitstream; and
decode the current block of the current picture using the determined global motion model.
2. The decoder of claim 1 , wherein the header includes a picture parameter set.
3. The decoder of claim 1 , wherein the header includes a sequence parameter set.
4. The decoder of claim 1 , wherein the global motion model includes a translational motion model.
5. The decoder of claim 1 , wherein the global motion model includes a four parameter affine motion model.
6. The decoder of claim 1 , wherein the global motion model includes a six parameter affine motion model.
7. The decoder of claim 1 further comprising:
an entropy decoder processor configured to receive the bit stream and decode the bitstream into quantized coefficients;
an inverse quantization and inverse transformation processor configured to process the quantized coefficients including performing an inverse discrete cosine;
a deblocking filter;
a frame buffer; and
an intra prediction processor.
8. The decoder of claim 1 , wherein the current block forms part of a quadtree plus binary decision tree.
9. The decoder of claim 1 , wherein the current block is a coding tree unit.
10. The decoder of claim 1 , wherein the current block is a coding unit.
11. A method, the method comprising:
receiving, by a decoder, a bitstream including a current coded block of a current picture;
detecting a header for the current coded block in the bitstream;
determining, using the header, a global motion model for the current block, the global motion model being one of translational motion, 4-paramter affine motion, or 6-parameter affine motion, wherein parameters for the determined global motion model are not explicitly signaled in the bitstream; and
decoding the current block of the current picture using the determined global motion model.
12. The method of claim 11 , wherein the header includes a picture parameter set.
13. The method of claim 11 , wherein the header includes a sequence parameter set.
14. The method of claim 11 , wherein the global motion model includes a translational motion model.
15. The method of claim 11 , wherein the global motion model includes a four parameter affine motion model.
16. The method of claim 11 , wherein the global motion model includes a six parameter affine motion model.
17. The method of claim 11 , wherein the decoder further comprises:
an entropy decoder processor configured to receive the bit stream and decode the bitstream into quantized coefficients;
an inverse quantization and inverse transformation processor configured to process the quantized coefficients including performing an inverse discrete cosine;
a deblocking filter;
a frame buffer; and
an intra prediction processor.
18. The method of claim 11 , wherein the current block forms part of a quadtree plus binary decision tree.
19. The method of claim 11 , wherein the current block is a coding tree unit.
20. The method of claim 11 , wherein the current block is a coding unit.