Video Bitstream Syntax Reordering for Parallel Decoding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current video coding standards face challenges in optimizing encoding and decoding run-time performance without compromising coding efficiency, particularly due to dependencies between CTU blocks reconstruction and in-loop filtering parameters signaling processes.
Innovation Solution
The method involves signaling CTU coded blocks data before CTU in-loop filtering parameters in the bitstream, allowing for increased parallelism in encoding and decoding processes by reordering the bitstream syntax to eliminate non-relevant dependencies and enable higher levels of parallel processing, thereby supporting higher resolutions and bitrates in real-time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If CTU in-loop filtering parameters are signaled before CTU coded blocks data in the bitstream, then in-loop filtering can be performed earlier in the decoding process, but the syntax parsing and reconstruction dependencies create complexity in the encoding/decoding structure
Solution Approach 1:
The patent inverts the conventional bitstream syntax order by signaling CTU coded blocks data before CTU in-loop filtering parameters. This reversal eliminates the dependency chain where filtering parameters were previously needed before block reconstruction, allowing parallel processing and reducing decoding time while maintaining structural manageability through this deliberate inversion.
Solution Approach 2:
The patent segments the bitstream syntax into distinct CTU-coded-blocks-data and CTU-in-loop-filtering-parameters sections, allowing independent parsing and processing of each segment. This segmentation enables the decoder to reconstruct CTU blocks without waiting for filtering parameters, reducing decoding time while keeping the segmented structure manageable through clear syntactic separation.
2Productivity
If higher resolutions and bitrates are processed in real-time, then video quality and data rate increase, but encoding and decoding run-time performance becomes more challenging
Solution Approach 1:
The patent introduces dynamic syntax reordering capability that adapts to different processing requirements. By making the bitstream syntax flexible and reorderable, the system can optimize the parsing sequence for real-time high-resolution processing, allowing the decoder to dynamically adjust the processing order of CTU blocks and filtering parameters to maintain real-time performance at higher bitrates.
Solution Approach 2:
The patent enables preliminary action by allowing CTU coded blocks data to be parsed and reconstructed before the corresponding in-loop filtering parameters are signaled. This preliminary reconstruction capability allows the decoder to prepare and process high-resolution video data in advance, improving real-time processing capability by reducing the critical path for block reconstruction.
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
The present application relates to signaling in a bitstream coded block data and in-loop filtering parameters of a video sequence comprising video pictures, each video picture being split into multiple coding tree units, denoted CTU, each CTU comprising CTU blocks, CTU coded blocks data being obtained for each CTU by encoding blocks of said CTU, reconstructed CTU blocks associated with a CTU being obtained by decoding CTU coded blocks data associated with said CTU, reconstructed CTU blocks associated with a CTU being filtered using in-loop filtering parameters associated with said CTU, denoted CTU in-loop filtering parameters, wherein the CTU coded blocks data associated with a CTU is signaled in the bitstream before the CTU in-loop filtering parameters associated with said CTU.