Range of minimum coding block size in video coding
An apparatus for video decoding includes circuitry configured to receive a syntax element from a bitstream of a coded video being included in a parameter set or a picture header and specifying a minimum luma coding block size, verify whether the minimum luma coding block size is within a range of allowable minimum luma coding block sizes having an upper limit smaller than a maximum allowable coding tree unit (CTU) size, and decode a coded picture referring the parameter set or including the picture header in the coded video based on the minimum luma coding block size. The upper limit of the range of allowable minimum luma coding block sizes can be a predefined maximum allowable minimum luma coding block size.
1. A method of video decoding at a video decoder, comprising:
receiving a first syntax element from a bitstream of a coded video, the first syntax element specifying a minimum luma coding block size;
verifying whether the minimum luma coding block size is within a range of allowable minimum luma coding block sizes having an upper limit smaller than a maximum allowable coding tree unit (CTU) size; and
in response to the minimum luma coding block size being within the range of allowable minimum luma coding block sizes, decoding a coded picture in the coded video based on the minimum luma coding block size,
wherein the first syntax element indicates a binary logarithm value of the minimum luma coding block size minus 2, and
the verifying includes verifying whether the binary logarithm value of the minimum luma coding block size minus 2 is in a range of 0 to Min(N, log 2_ctu_size_minus5+3), inclusive, where N is 4, and log 2_ctu_size_minus5+5 represents a binary logarithm value of a CTU size of the coded video.
2. The method of claim 1 , further comprising:
receiving a second syntax element from the bitstream of the coded video, the second syntax element specifying CTU size.
3. An apparatus of video decoding, comprising circuitry configured to:
receive a first syntax element from a bitstream of a coded video, the first syntax element specifying a minimum luma coding block size;
verify whether the minimum luma coding block size is within a range of allowable minimum luma coding block sizes having an upper limit smaller than a maximum allowable coding tree unit (CTU) size; and
in response to the minimum luma coding block size being within the range of allowable minimum luma coding block sizes, decode a coded picture in the coded video based on the minimum luma coding block size,
wherein the first syntax element indicates a binary logarithm value of the minimum luma coding block size minus 2, and
the circuitry is further configured to:
verify whether the binary logarithm value of the minimum luma coding block size minus 2 is in a range of 0 to Min(N, log 2_ctu_size_minus5+3), inclusive, where N is 4, and log 2_ctu_size_minus5+5 represents a binary logarithm value of a CTU size of the coded video.
4. The apparatus of claim 3 , wherein the circuitry is further configured to:
receive a second syntax element from the bitstream of the coded video, the second syntax element specifying the CTU size.
5. A non-transitory computer-readable medium storing instructions that, when executed by a processor, cause the processor to perform a method of video decoding, the method comprising:
receiving a first syntax element from a bitstream of a coded video, the first syntax element specifying a minimum luma coding block size;
verifying whether the minimum luma coding block size is within a range of allowable minimum luma coding block sizes having an upper limit smaller than a maximum allowable coding tree unit (CTU) size; and
in response to the minimum luma coding block size being within the range of allowable minimum luma coding block sizes, decoding a coded picture in the coded video based on the minimum luma coding block size,
wherein the first syntax element indicates a binary logarithm value of the minimum luma coding block size minus 2, and
the verifying includes verifying whether the binary logarithm value of the minimum luma coding block size minus 2 is in a range of 0 to Min(N, log 2_ctu_size_minus5+3), inclusive, where N is 4, and log 2_ctu_size_minus5+5 represents a binary logarithm value of a CTU size of the coded video.