US Patent Application 18054054. SIGNALING OF DOWNSAMPLING FILTERS FOR CHROMA FROM LUMA INTRA PREDICTION MODE simplified abstract
Contents
SIGNALING OF DOWNSAMPLING FILTERS FOR CHROMA FROM LUMA INTRA PREDICTION MODE
Organization Name
Inventor(s)
Liang Zhao of Sunnyvale CA (US)
SIGNALING OF DOWNSAMPLING FILTERS FOR CHROMA FROM LUMA INTRA PREDICTION MODE - A simplified explanation of the abstract
This abstract first appeared for US patent application 18054054 titled 'SIGNALING OF DOWNSAMPLING FILTERS FOR CHROMA FROM LUMA INTRA PREDICTION MODE
Simplified Explanation
This patent application describes methods and apparatuses for performing chroma from luma (CfL) intra prediction in video coding.
- The invention involves receiving a current block from a coded video bitstream.
- The invention obtains a syntax element from the bitstream, which indicates the downsampling filter used for predicting the current block in a CfL intra prediction mode.
- If the syntax element indicates the use of a first downsampling filter, the invention determines a set of filter coefficients based on that filter and downsamples the current block using a specific number of sampling positions.
- If the syntax element indicates the use of a second downsampling filter, the invention determines a different set of filter coefficients based on that filter and downsamples the current block using a different number of sampling positions.
- The invention then reconstructs the current block after downsampling it.
Original Abstract Submitted
Methods and apparatuses for performing chroma from luma (CfL) intra prediction, including: receiving a current block from a coded video bitstream; obtaining, from the coded video bitstream, a syntax element indicating which of two or more downsampling filters is used for predicting the current block in a CfL intra prediction mode; in response to the syntax element indicating that a first downsampling filter is used for the current block: determining a plurality of filter coefficients according to the first downsampling filter; and downsampling the current block based on the determined plurality of coefficients using a first number of sampling positions; in response to the syntax element indicating that a second downsampling filter is used for the current block: determining the plurality of filter coefficients according to the second downsampling filter; downsampling the current block based on the determined plurality of coefficients using a second number of sampling positions, wherein the second number of sampling positions are different from the first number of sampling positions; and reconstructing the current block after downsampling the current block.
