Setting intra-block copy virtual buffer based on virtual pipeline data unit
A method of video processing is described. The method includes determining, for a conversion between a current video block of a video picture of a video and a coded representation of the video, whether or how to reset reference sample values of a reference region of the video picture used for predicting the current video block according to a rule; and performing the conversion based on the determining.
1. A method of processing video data, comprising:
determining, for a conversion between a current video block of a video picture of a video and a bitstream of the video, that a prediction mode is applied to derive prediction samples of the current video block;
maintaining, for the prediction mode, a virtual buffer comprising one or more reference samples derived from reconstructed blocks of the video picture; and
performing the conversion based on the determining,
wherein in the prediction mode, reference samples determined by a block vector in the virtual buffer are used for the derivation of the prediction samples,
wherein when the virtual buffer is a luma buffer, positions of unavailable reference samples in the virtual buffer are determined based on positions of the current video block,
wherein when the virtual buffer is a chroma buffer, positions of unavailable reference samples in the virtual buffer are independent of positions of the current video block, and
wherein the unavailable reference samples in the virtual buffer are not allowed for the derivation of the prediction samples.
2. The method of claim 1 , wherein when the virtual buffer is the chroma buffer, the reference samples in the virtual buffer are disallowed to be marked unavailable.
3. The method of claim 1 , wherein when the current video block is a first luma block in a virtual unit and the virtual buffer is the luma buffer, reference samples in the virtual buffer corresponding to the virtual unit are marked unavailable.
4. The method of claim 1 , wherein when a size of a virtual unit is greater or equal to a width of the current video block and is greater or equal to a height of the current video block and the virtual buffer is the luma buffer, reference samples in the virtual buffer corresponding to the virtual unit are marked unavailable, and
wherein the size of the virtual unit is equal to min(ctbSize, 64), where ctbSize denotes a width or a height of a coding tree block of the video picture.
5. The method of claim 1 , wherein when a size of a virtual unit is less than a width of the current video block and is less than a height of the current video block and the virtual buffer is the luma buffer, reference samples in the virtual buffer corresponding to the current video block are marked unavailable, and
wherein the size of the virtual unit is equal to min(ctbSize, 64), where ctbSize denotes a width or a height of a coding tree block of the video picture.
6. The method of claim 1 , wherein when a variable is set to indicate resetting the virtual buffer and the virtual buffer is the luma buffer, the virtual buffer is reset, and
wherein when the virtual buffer is the chroma buffer, the virtual buffer is disallowed to be reset.
7. The method of claim 6 , wherein when the virtual buffer is reset, the reference samples in the virtual buffer are reset to be −1.
8. The method of claim 1 , wherein the unavailable reference samples have a value of −1.
9. The method of claim 1 , wherein the conversion comprises encoding the current video block into the bitstream.
10. The method of claim 1 , wherein the conversion comprises decoding the current video block from the bitstream.
11. An apparatus for processing video data comprising a processor and a non-transitory memory with instructions thereon, wherein the instructions upon execution by the processor, cause the processor to:
determine, for a conversion between a current video block of a video picture of a video and a bitstream of the video, that a prediction mode is applied to derive prediction samples of the current video block;
maintain, for the prediction mode, a virtual buffer comprising one or more reference samples derived from reconstructed blocks of the video picture; and
perform the conversion based on the determining,
wherein in the prediction mode, reference samples determined by a block vector in the virtual buffer are used for the derivation of the prediction samples,
wherein when the virtual buffer is a luma buffer, positions of unavailable reference samples in the virtual buffer are determined based on positions of the current video block,
wherein when the virtual buffer is a chroma buffer, positions of unavailable reference samples in the virtual buffer are independent of positions of the current video block, and
wherein the unavailable reference samples in the virtual buffer are not allowed for the derivation of the prediction samples.
12. The apparatus of claim 11 , wherein when the virtual buffer is the chroma buffer, the reference samples in the virtual buffer are disallowed to be marked unavailable.
13. The apparatus of claim 11 , wherein when the current video block is a first luma block in a virtual unit and the virtual buffer is the luma buffer, reference samples in the virtual buffer corresponding to the virtual unit are marked unavailable.
14. The apparatus of claim 11 , wherein when a size of a virtual unit is greater or equal to a width of the current video block and is greater or equal to a height of the current video block and the virtual buffer is the luma buffer, reference samples in the virtual buffer corresponding to the virtual unit are marked unavailable, and
wherein the size of the virtual unit is equal to min(ctbSize, 64), where ctbSize denotes a width or a height of a coding tree block of the video picture; or
wherein when a size of a virtual unit is less than a width of the current video block and is less than a height of the current video block and the virtual buffer is the luma buffer, reference samples in the virtual buffer corresponding to the current video block are marked unavailable, and
wherein the size of the virtual unit is equal to min(ctbSize, 64), where ctbSize denotes a width or a height of a coding tree block of the video picture.
15. A non-transitory computer-readable storage medium storing instructions that cause a processor to:
determine, for a conversion between a current video block of a video picture of a video and a bitstream of the video, that a prediction mode is applied to derive prediction samples of the current video block;
maintain, for the prediction mode, a virtual buffer comprising one or more reference samples derived from reconstructed blocks of the video picture; and
perform the conversion based on the determining,
wherein in the prediction mode, reference samples determined by a block vector in the virtual buffer are used for the derivation of the prediction samples,
wherein when the virtual buffer is a luma buffer, positions of unavailable reference samples in the virtual buffer are determined based on positions of the current video block,
wherein when the virtual buffer is a chroma buffer, positions of unavailable reference samples in the virtual buffer are independent of positions of the current video block, and
wherein the unavailable reference samples in the virtual buffer are not allowed for the derivation of the prediction samples.
16. The non-transitory computer-readable storage medium of claim 15 , wherein when the virtual buffer is the chroma buffer, the reference samples in the virtual buffer are disallowed to be marked unavailable.
17. The non-transitory computer-readable storage medium of claim 15 , wherein when the current video block is a first luma block in a virtual unit and the virtual buffer is the luma buffer, reference samples in the virtual buffer corresponding to the virtual unit are marked unavailable.
18. The non-transitory computer-readable storage medium of claim 15 , wherein when a size of a virtual unit is greater or equal to a width of the current video block and is greater or equal to a height of the current video block and the virtual buffer is the luma buffer, reference samples in the virtual buffer corresponding to the virtual unit are marked unavailable, and
wherein the size of the virtual unit is equal to min(ctbSize, 64), where ctbSize denotes a width or a height of a coding tree block of the video picture.
19. The non-transitory computer-readable storage medium of claim 15 , wherein when a size of a virtual unit is less than a width of the current video block and is less than a height of the current video block and the virtual buffer is the luma buffer, reference samples in the virtual buffer corresponding to the current video block are marked unavailable, and
wherein the size of the virtual unit is equal to min(ctbSize, 64), where ctbSize denotes a width or a height of a coding tree block of the video picture.
20. A non-transitory computer-readable recording medium storing a bitstream of a video which is generated by a method performed by a video processing apparatus, wherein the method comprises:
determining, for a current video block of a video picture of the video, that a prediction mode is applied to derive prediction samples of the current video block;
maintaining, for the prediction mode, a virtual buffer comprising one or more reference samples derived from reconstructed blocks of the video picture; and
generating the bitstream based on the determining,
wherein in the prediction mode, reference samples determined by a block vector in the virtual buffer are used for the derivation of the prediction samples,
wherein when the virtual buffer is a luma buffer, positions of unavailable reference samples in the virtual buffer are determined based on positions of the current video block,
wherein when the virtual buffer is a chroma buffer, positions of unavailable reference samples in the virtual buffer are independent of positions of the current video block, and
wherein the unavailable reference samples in the virtual buffer are not allowed for the derivation of the prediction samples.