US 12,113,990 B2 · Method and apparatus for video coding

Abstract

Aspects of the disclosure provide methods and apparatuses for video encoding/decoding. Processing circuitry in an apparatus decodes coded information of a coding unit (CU) from a coded video bitstream. The coded information indicates a last position of non-zero transform coefficients of a first coding block (CB) of the CU. The processing circuitry determines whether a secondary transform index is signaled in the coded information based at least on comparison to a threshold value and whether to perform a secondary transform on a second CB of the CU based on whether the secondary transform index is determined to be signaled in the coded information. When the secondary transform is determined to be performed, the processing circuitry performs the secondary transform on the second CB and reconstructs the second CB. When the secondary transform is determined not performed, the second CB is reconstructed without performing the secondary transform on the second CB.

Claims12

Dependent claims

A method for video decoding, comprising:

decoding coding information of a coding unit (CU) from a coded video bitstream, the coding information indicating a size of the CU, the CU including at least one chroma block;
determining a maximum transform unit (TU) size in the CU from the coded video bitstream;
determining a CU width threshold and a CU height threshold, the CU width threshold and the CU height threshold being both less than the maximum TU size;
and
determining whether a secondary transform is allowed for the CU including the at least one chroma block, wherein
when the secondary transform is allowed and a secondary transform index for the secondary transform is signaled, the size of the CU is less than or equal to the CU width threshold or the CU height threshold.

3 more elements

A method for video encoding, comprising:

determining whether a secondary transform is allowed based on a size of a coding unit (CU), a CU width threshold, and a CU height threshold, the CU width threshold and the CU height threshold being both less than a maximum transform unit (TU) size in the CU;
and
encoding coding information of the CU in a coded video bitstream based on whether the secondary transform is determined to be allowed, the coding information indicating the size of the CU, wherein
when the size of the CU is less than or equal to the CU width threshold or the CU height threshold, the secondary transform is allowed and a secondary transform index for the secondary transform is signaled in the coding information.

1 more element

A method of processing visual media data, the method comprising:

processing a bitstream of the visual media data according to a format rule, wherein
the bitstream includes coding information of a coding unit (CU), the coding information indicating a size of the CU, the CU including at least one chroma block;
and
the format rule specifies that
a maximum transform unit (TU) size in the CU is determined from the bitstream,
a CU width threshold and a CU height threshold are both less than the maximum TU size,
whether a secondary transform is allowed for the CU including the at least one chroma block is determined, and
when the secondary transform is allowed and a secondary transform index for the secondary transform is signaled, the size of the CU is less than or equal to the CU width threshold or the CU height threshold.

5 more elements

Dependencies are inferred from the claim text.

Method and apparatus for video coding

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Method and apparatus for video coding

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Abstract

Claims12