Intra-Refresh Video Codec Row Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional video signal processing techniques face challenges in efficiently encoding video frames, leading to error propagation and increased bit rates due to the insertion of I-frames, which can result in undesired user experiences and visual effects.
Innovation Solution
A video codec that divides video frames into row segments, selectively encodes them using intra-prediction and inter-prediction, limits the vertical global motion vector to zero, adjusts the number of row segments based on the search range, and disables loop filtering to prevent error propagation and optimize bit distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If I-frames are inserted to stop error propagation, then reliability is improved, but bit rate increases and user experience deteriorates
Solution Approach 1:
The patent segments the frame into multiple row segments and processes them independently through separate prediction paths (intra-prediction for refresh rows, inter-prediction for non-refresh rows). This segmentation allows selective refreshing of specific row segments without requiring complete I-frames, thereby preventing error propagation in critical areas while maintaining lower bit rates compared to full I-frame insertion.
2Reliability
If intra-prediction is used for all blocks, then error propagation is stopped, but encoding complexity and bit rate increase
Solution Approach 1:
The patent applies different prediction methods to different spatial locations within the frame. Specifically, refresh rows use intra-prediction to prevent error propagation, while non-refresh rows use inter-prediction to maintain lower bit rates. This local differentiation allows the system to achieve error prevention where needed without incurring the penalty of applying intra-prediction globally to the entire frame.
3Quantity of substance
If P-frames and B-frames are used for compression, then bit rate is reduced, but error propagation occurs through frames
Solution Approach 1:
The patent segments the frame into refresh and non-refresh row segments, allowing selective error prevention in critical areas while maintaining the efficiency of P/B-frames in other areas. This segmentation enables the system to use inter-prediction (low bit rate) where errors can propagate, and intra-prediction (error prevention) where reliability is critical, thus balancing bit rate and error propagation prevention.
Solution Approach 2:
The patent applies different prediction qualities to different spatial locations: high-quality intra-prediction for refresh rows that require error prevention, and lower-quality inter-prediction for non-refresh rows where bit rate efficiency is prioritized. This local quality differentiation allows the system to achieve overall error propagation prevention without the penalty of uniform high-quality encoding across the entire frame.
4Manufacturing precision
If loop filtering is applied at slice boundaries, then encoding quality is improved, but error propagation is not prevented during refresh duration
Solution Approach 1:
The patent performs preliminary action by disabling loop filtering at slice boundaries during the refresh duration before errors can propagate. This preliminary prevention measure ensures that errors are blocked from spreading through the refresh rows before they can affect subsequent processing, thereby maintaining reliability while still allowing quality improvement in non-refresh areas through normal loop filtering.
Data Source
AI summary
A video codec for encoding a sequence of video frames divides a video frame area into number of row segments. The Video encoder selects a different set of row segments in each video frame in a set of video frames and encodes the selected set of row segments by intra-prediction. As a result, the selected part of the frame is intra-refreshed. The video codec limits the maximum value of the vertical global motion vector GMVy to zero and video codec adjust the number of row segments in the select set of row segments based on the height of the search range configured for the motion estimation. As a result, the video codec may not refer to an un-refreshed portion in the previous frame for encoding an already refreshed area of the current frame.