Variable-Complexity Image Decoding Synchronization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current scalable coding and decoding technologies face challenges in maintaining synchronization between encoders and decoders, leading to image drift due to differences in decoding complexity, particularly when less complex tools are used for decoding.
Innovation Solution
The method involves identifying control images and intermediate images, where control images are decoded using predetermined tools to maintain synchronization, and intermediate images can be decoded using tools selected by the decoder, allowing for variable complexity decoding without affecting the coding process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If less complex decoding tools are used to reduce decoding complexity, then decoding resource consumption is reduced, but image drift occurs due to desynchronization between encoder and decoder
Solution Approach 1:
The patent segments the bitstream into multiple layers (base layer and enhancement layers), allowing decoders to selectively decode only the base layer for low complexity or add enhancement layers for higher quality. This segmentation enables flexible complexity adaptation while maintaining synchronization through the mandatory base layer decoding that both encoder and decoder agree upon.
Solution Approach 2:
The patent changes the parameter of decoding complexity by introducing multiple hierarchical levels with different quality and resolution. The base layer uses standard decoding tools to ensure synchronization, while enhancement layers can use simplified tools for complexity reduction, allowing the system to adapt decoding complexity without compromising the fundamental synchronization between encoder and decoder.
2Adaptability or versatility
If different decoding tools are used for intermediate images to adapt to decoder resources, then decoding flexibility is improved, but image quality degradation occurs
Solution Approach 1:
The patent implements a nested structure where the base layer (decoded with standard tools for quality assurance) is embedded within the overall bitstream, and enhancement layers (which can use simplified decoding tools) are nested around it. This nested architecture allows decoders to flexibly adapt resources by choosing to decode only the base layer or adding enhancement layers, with the understanding that base layer quality provides a reliable foundation.
Solution Approach 2:
The patent applies partial action by allowing decoders to selectively decode only the necessary portion of the bitstream (base layer only, or base plus some enhancement layers) based on available resources. This partial decoding approach provides flexibility in adapting to decoder capabilities while accepting that full image quality is achieved only when all layers are decoded with appropriate tools.
3Loss of information
If hierarchical prediction with inter-layer prediction is used to limit redundancy, then data efficiency is improved, but decoding drift occurs when reference images are not identical
Solution Approach 1:
The patent extracts the critical synchronization function into the base layer, which contains all essential reference information decoded using standard tools that both encoder and decoder agree upon. By taking out the reference image generation into this dedicated base layer, the patent ensures that reference images remain identical between encoder and decoder, preventing drift while still allowing enhancement layers to use simplified decoding tools for complexity reduction.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a method for decoding a digital image signal in a decoding terminal, that uses a variable-complexity decoding, enabling, for at least one step in the decoding, the selection of at least one decoding tool from at least two available decoding tools. The method includes the following steps: identifying from said images first so-called control images and second so-called intermediate images; applying to each of said control images, for at least one step of the decoding, at least one predetermined decoding tool imposed by the signal; applying to at least one of said intermediate images, for at least one step of the decoding, at least one decoding tool selected by said decoding terminal and not imposed by said signal.