Block-Size Adaptive Intra Prediction for Video Compression
Solution Overview
Problem
Existing video encoding and decoding methods face challenges in achieving high compression rates with minimal image quality degradation due to limitations in bandwidth and the need for efficient removal of spatial and temporal redundancies in video data.
Innovation Solution
The method involves determining an intra prediction mode for a current block based on its size and shape, selecting an appropriate interpolation filter set, and using it to predict pixel values, thereby improving the efficiency of intra prediction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the number of prediction methods is increased to improve prediction accuracy, then the accuracy of prediction increases, but the size of encoding information increases
Solution Approach 1:
The patent applies parameter changes by dynamically adjusting the intra prediction mode based on block size parameters. Different block sizes (e.g., 4×4, 8×8, 16×16) use different prediction mode sets, where larger blocks use fewer directional modes and smaller blocks use more directional modes. This resolves the contradiction by adapting the prediction accuracy level to the block size, preventing unnecessary encoding overhead for large blocks while maintaining sufficient accuracy for small blocks.
2Loss of information
If a data unit size is increased to reduce encoding information, then the encoding information decreases, but the accuracy of prediction decreases
Solution Approach 1:
The patent applies segmentation by dividing the picture into blocks of various sizes and applying different intra prediction mode configurations to different block size segments. Small blocks (e.g., 4×4) receive more prediction modes for higher accuracy, while large blocks (e.g., 16×16 or larger) use fewer modes to reduce encoding overhead. This segmented approach resolves the contradiction by optimizing the trade-off between prediction accuracy and encoding information size for each block size segment.
3Productivity
If compression rate is increased to improve transmission efficiency, then the compression rate increases, but image quality degrades
Solution Approach 1:
The patent applies dynamics by making the intra prediction mode selection adaptive and dynamic rather than static. The encoder dynamically chooses from different prediction mode configurations based on block size, and the decoder dynamically reconstructs using the same adaptive logic. This dynamic adaptation allows the system to achieve higher compression rates by using fewer modes for large blocks while maintaining image quality through more modes for small blocks, resolving the contradiction between compression rate and image quality.
Data Source
AI summary
Provided is a video decoding method including: obtaining, from a bitstream, intra prediction mode information indicating an intra prediction mode of a current block; determining an interpolation filter set to be used in prediction of the current block, based on at least one of a size of the current block and the intra prediction mode indicated by the intra prediction mode information; determining a reference location to which a current sample of the current block refers according to the intra prediction mode; determining, in the interpolation filter set, an interpolation filter that corresponds to the reference location; determining a prediction value of the current sample, according to reference samples of the current block and the interpolation filter; and reconstructing the current block, based on the prediction value of the current sample.