Method and apparatus for signaling of chroma quantization parameters
AssigneeTencent America LLC
InventorsLing Li, Xiang Li, Shan Liu
Life of this patent
Estimating the term…
Abstract
According to an aspect of the disclosure, a method of video decoding performed in a video decoder is provided. In the method, syntax information of a coding unit (CU) is decoded from a coded video bitstream. The syntax information is signaled in a picture header (PH) and includes chroma quantization parameter (QP) offsets in a PH level. The chroma QP offsets include at least one of a Cb offset, a Cr offset, and a CbCr offset. Further, quantization parameters for the CU are determined based on the chroma QP offsets in the PH level and a quantization parameter range offset of the CU.
Claims20
A method of video encoding performed in a video encoder, the method comprising:
- generating syntax information associated with a coding unit (CU) of a region in a picture, the syntax information including chroma quantization parameter (QP) offsets in a picture header (PH) level, the chroma QP offsets in the PH level including at least one of a Cb offset, a Cr offset, and a CbCr offset;
- and
- determining quantization parameters for the CU based on joint chroma QP offsets included at a plurality of levels of the syntax information and a quantization parameter range offset of the CU, the joint chroma QP offsets including the chroma QP offsets in the PH level,
- wherein the chroma QP offsets are included in the PH level in response to a chroma array type not being monochrome or not being a chroma format 4:4:4 with a separate color plane flag equal to 1.
A method of video encoding performed in a video encoder, the method comprising:
- generating first syntax information of a coding unit (CU) of a region in response to offset information being a first value, the first syntax information being included in a picture header (PH) and including chroma quantization parameter (QP) offsets in a PH level, the chroma QP offsets in the PH level including at least one of a Cb offset, a Cr offset, and a CbCr offset;
- and
- determining quantization parameters for the CU based on joint chroma QP offsets included at a plurality of syntax levels associated with the CU and a quantization parameter range offset of the CU, the joint chroma QP offsets including the chroma QP offsets in the PH level in response to the offset information being the first value,
- wherein the first syntax information is included in the PH level in response to a chroma array type not being monochrome or not being a chroma format 4:4:4 with a separate color plane flag equal to 1.
An apparatus for video encoding, comprising:
- processing circuitry configured to:
- generate syntax information associated with a coding unit (CU) of a region in a picture, the syntax information including chroma quantization parameter (QP) offsets in a picture header (PH) level, the chroma QP offsets in the PH level including at least one of a Cb offset, a Cr offset, and a CbCr offset;
- and
- determine quantization parameters for the CU based on joint chroma QP offsets included at a plurality of levels of the syntax information and a quantization parameter range offset of the CU, the joint chroma QP offsets including the chroma QP offsets in the PH level,
- wherein the chroma QP offsets are included in the PH level in response to a chroma array type not being monochrome or not being a chroma format 4:4:4 with a separate color plane flag equal to 1.
Dependencies are inferred from the claim text.