Intra-frame prediction coding method and apparatus, electronic device, and computer storage medium

An intra-frame prediction coding apparatus, comprising:

• processing circuitry configured to
• determine N candidate intra-frame prediction modes for a current coding block, and save the N candidate intra-frame prediction modes to a candidate mode list, N being a positive integer;
• obtain optimal coding modes respectively corresponding to spatially neighboring coding blocks and an upper-layer coding block of the current coding block, and save the optimal coding modes respectively corresponding to the spatially neighboring coding blocks and the upper-layer coding block to a neighboring mode list;
• and
• determine an optimal coding mode for the current coding block based on the candidate mode list and the neighboring mode list, wherein
• the spatially neighboring coding blocks comprise at least one of a first coding block adjacent to the current coding block and located at a left side of the current coding block, a second coding block adjacent to the current coding block and located at an upper side of the current coding block, a third coding block adjacent to the first coding block and located at an upper side of the first coding block, a fourth coding block adjacent to the first coding block and located at a lower side of the first coding block, and a fifth coding block adjacent to the second coding block and located at a right side of the second coding block,
• to determine the N candidate intra-frame prediction modes, the processing circuitry is configured to sort predetermined rate-distortion optimization cost values respectively corresponding to a plurality of predetermined intra-frame prediction modes according to a first predetermined order, and use N top-ranking intra-frame prediction modes as the candidate intra-frame prediction modes for the current coding block,
• to save the N candidate intra-frame prediction modes to the candidate mode list, the processing circuitry is configured to successively save the N candidate intra-frame prediction modes to the candidate mode list according to the first predetermined order, and
• to save the optimal coding modes respectively corresponding to the spatially neighboring coding blocks and the upper-layer coding block to the neighboring mode list, the processing circuitry is configured to successively save the optimal coding mode for the at least one of the first coding block, the second coding block, the third coding block, the fourth coding block, and the fifth coding block and the optimal coding mode for the upper-layer coding block to the neighboring mode list according to a second predetermined order.

A non-transitory computer-readable storage medium, storing computer-readable instructions, which, when executed by one or more processors, cause the one or more processors to perform an intra-frame prediction coding method comprising:

• determining N candidate intra-frame prediction modes for a current coding block, and saving the N candidate intra-frame prediction modes to a candidate mode list, N being a positive integer;
• obtaining optimal coding modes respectively corresponding to spatially neighboring coding blocks and an upper-layer coding block of the current coding block, and saving the optimal coding modes respectively corresponding to the spatially neighboring coding blocks and the upper-layer coding block to a neighboring mode list;
• and
• determining an optimal coding mode for the current coding block based on the candidate mode list and the neighboring mode list, wherein
• the spatially neighboring coding blocks comprise at least one of a first coding block adjacent to the current coding block and located at a left side of the current coding block, a second coding block adjacent to the current coding block and located at an upper side of the current coding block, a third coding block adjacent to the first coding block and located at an upper side of the first coding block, a fourth coding block adjacent to the first coding block and located at a lower side of the first coding block, and a fifth coding block adjacent to the second coding block and located at a right side of the second coding block,
• the determining the N candidate intra-frame prediction modes includes sorting predetermined rate-distortion optimization cost values respectively corresponding to a plurality of predetermined intra-frame prediction modes according to a first predetermined order, and using N top-ranking intra-frame prediction modes as the candidate intra-frame prediction modes for the current coding block,
• the saving the N candidate intra-frame prediction modes to the candidate mode list includes successively saving the N candidate intra-frame prediction modes to the candidate mode list according to the first predetermined order, and
• the saving the optimal coding modes respectively corresponding to the spatially neighboring coding blocks and the upper-layer coding block to the neighboring mode list includes successively saving the optimal coding mode for the at least one of the first coding block, the second coding block, the third coding block, the fourth coding block, and the fifth coding block and the optimal coding mode for the upper-layer coding block to the neighboring mode list according to a second predetermined order.