Adaptive Deblocking Filter Length for Block Boundary Smoothing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing image compression technologies face challenges in determining the optimal filter length and boundary strength of deblocking filters, particularly in high-resolution and high-quality image encoding/decoding processes, leading to inefficiencies in smoothing effects at block boundaries.
Innovation Solution
The method and device adaptively determine the filter length and boundary strength of deblocking filters based on factors such as multi-reference prediction, block size, and motion vector differences, allowing precise application of deblocking filters at block boundaries.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a fixed filter length and boundary strength are used for deblocking filters, then the implementation is simple, but the smoothing effect at block boundaries is insufficient for high-resolution images
Solution Approach 1:
The patent applies dynamics by making the filter length and boundary strength variable rather than fixed. The filter length is dynamically selected from multiple candidate lengths (e.g., 3, 5, 7, 9) based on block characteristics, and the boundary strength is dynamically determined based on prediction mode and motion vector differences. This allows the deblocking filter to adapt to different image regions and resolutions, improving smoothing precision without requiring a completely complex system design.
Solution Approach 2:
The patent changes parameters (filter length and boundary strength) based on specific image characteristics. The filter length parameter is changed according to block size and position, while the boundary strength parameter is changed based on prediction mode and motion vector analysis. This parameter adaptation enables the system to achieve high smoothing precision for high-resolution images while maintaining reasonable implementation complexity through rule-based parameter selection.
2Manufacturing precision
If adaptive filter parameters are used based on multi-reference prediction and motion vectors, then the smoothing effect is improved, but the computational complexity increases
Solution Approach 1:
The patent applies local quality by determining filter parameters specifically for each block boundary based on local characteristics. The boundary strength is determined separately for each block pair using their specific prediction modes and motion vectors. The filter length is selected based on local block size and position information. This localized parameter determination improves smoothing precision at critical block boundaries while avoiding unnecessary computational complexity in regions where simple filtering suffices.
Solution Approach 2:
The patent implements partial action by selectively applying complex adaptive parameter determination only where needed. The system uses motion vector difference thresholds to determine when full adaptive processing is necessary versus when simpler filtering can suffice. By applying the computationally intensive parameter adaptation selectively rather than universally, the system achieves improved smoothing precision at important boundaries while controlling overall computational power consumption.
3Manufacturing precision
If the filter length is increased to improve smoothing, then the boundary artifacts are reduced, but the processing time increases
Solution Approach 1:
The patent uses dynamics by making the filter length adaptive rather than always using the maximum length. The filter length is dynamically selected from candidate values (3, 5, 7, 9) based on block characteristics such as size, position, and prediction mode. This dynamic selection allows the system to use longer filters only when boundary artifacts are severe, while using shorter, faster filters in regions where they are sufficient, thereby reducing overall processing time while maintaining effective artifact reduction where needed.
Solution Approach 2:
The patent changes the filter length parameter based on specific image characteristics rather than using a fixed long filter. The parameter is adjusted according to block size, position in the image, and prediction mode. This parameter adaptation enables the system to achieve effective boundary artifact reduction in critical areas using appropriately sized filters, while avoiding the excessive processing time that would result from uniformly applying long filters across the entire image.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An image decoding/encoding method and device, according to the present disclosure, can determine a filter length of a deblocking filter applied to a block boundary between a first block and a second block in the current picture, determine a boundary strength of the deblocking filter, determine a deblocking filter having a predetermined type and strength on the basis of the filter length and the boundary strength, and apply the deblocking filter to the block boundary between the first block and the second block. Here, the filter length of the deblocking filter can be determined on the basis of whether multiple reference prediction is applied to the first block and/or the second block.