Adaptive Interpolation Filter Selection for Motion-Compensated Prediction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing image compression technologies lack the ability to adaptively determine and signal interpolation filters effectively, leading to inefficiencies in encoding and decoding processes.
Innovation Solution
An adaptive interpolation filter technique is employed, where an interpolation filter for a current block is determined based on a candidate list, using index information signaled from a bitstream, and the filter is selected based on the resolution of the motion vector difference (MVD) and inter prediction mode, allowing for improved matching of filter characteristics to the video sequence.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If an adaptive interpolation filter technique is employed with a candidate list, then encoding efficiency and prediction block quality are improved, but device complexity and signaling requirements increase
Solution Approach 1:
The patent applies parameter changes by dynamically selecting interpolation filters from a candidate list based on motion vector difference resolution and prediction mode. The system changes the filter parameters (kernel size, coefficients) adaptively according to the specific block characteristics, thereby improving encoding efficiency without requiring a complete redesign of the filtering mechanism. This resolves the contradiction by enabling selective adaptation rather than universal complexity.
Solution Approach 2:
The patent segments the interpolation filter selection process into distinct candidate lists organized by motion vector difference resolution (1/2-pel, 1/4-pel, 1/8-pel). Each segment contains filters optimized for specific resolution requirements, allowing the decoder to efficiently select from pre-organized groups rather than evaluating all possible filters. This segmentation reduces the effective search space and computational complexity.
2Measurement precision
If interpolation filter information is signaled explicitly from the bitstream, then filter selection accuracy is improved, but bit transmission increases
Solution Approach 1:
The patent applies local quality by deriving interpolation filter information locally from existing AMVR (Adaptive Motion Vector Resolution) flags and indices that are already present in the bitstream. Instead of explicitly signaling filter selection for every block, the system uses the locally available AMVR parameters to determine the appropriate filter, thereby achieving accurate filter selection without additional bit transmission overhead.
Solution Approach 2:
The patent implements self-service by enabling the decoding apparatus to autonomously determine interpolation filter characteristics using existing bitstream information (AMVR flags and indices). The system serves itself by deriving filter parameters from already-transmitted motion compensation data, eliminating the need for separate explicit signaling and reducing overall bit transmission requirements.
3Adaptability or versatility
If multiple interpolation filter candidates are maintained in a candidate list, then adaptability to different video sequence characteristics is improved, but processing complexity increases
Solution Approach 1:
The patent applies dynamics by organizing the candidate list into multiple groups corresponding to different motion vector difference resolutions (1/2-pel, 1/4-pel, 1/8-pel). The system dynamically selects which candidate group to use based on the current block's AMVR parameters, enabling adaptability to different video sequence characteristics while maintaining a manageable processing complexity through structured organization rather than evaluating all filters simultaneously.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An image decoding/encoding method and apparatus according to the present disclosure may comprise: determining an interpolation filter of a current block; and generating a prediction sample of the current sample on the basis of the interpolation filter of the current block. Here, on the basis of the resolution of a motion vector difference (MVD) for the current block, the interpolation filter of the current block may be determined on the basis of a candidate list including a plurality of interpolation filter candidates.