Deblocking Filter Parameter Variation for Video Comfort Noise
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for adding comfort noise to videos to mitigate artificial stillness caused by low frame rates or encoding techniques result in unnatural video playback, often requiring non-standard decoders or increasing bitrate.
Innovation Solution
Varying the parameters of a deblocking filter during video encoding introduces synthetic temporal noise, allowing for comfort noise addition within standard codecs like h.264 without requiring special encoders or decoders, while minimizing bitrate increase.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If a low frame rate is used to reduce bandwidth consumption, then bandwidth efficiency is improved, but the video appears unnatural and frozen due to absence of temporal noise
Solution Approach 1:
The patent changes the parameters of the deblocking filter dynamically during video encoding. By varying parameters such as beta and tc offsets based on motion detection, the filter introduces temporal noise that prevents the video from appearing frozen, while maintaining efficient compression at low frame rates.
Solution Approach 2:
The deblocking filter parameters are made dynamic rather than static. The encoder detects motion between frames and adjusts the deblocking strength accordingly - applying stronger filtering when motion is detected to introduce comfort noise, and weaker filtering when motion is minimal, thus adapting to scene conditions.
2Productivity
If encoding techniques with varying compression levels are used to handle motion, then compression efficiency is improved, but empty blocks introduce artificial stillness due to lack of temporal noise
Solution Approach 1:
The patent applies different deblocking filter strengths to different regions of the video frame based on local motion characteristics. Areas with motion receive stronger filtering to introduce comfort noise, while static areas receive lighter filtering, thus maintaining compression efficiency while preventing artificial stillness in motion regions.
Solution Approach 2:
The deblocking filter parameters are adjusted locally based on motion detection in different blocks. The encoder varies beta and tc offsets for different regions, introducing temporal noise selectively in areas where motion is detected, thereby maintaining natural appearance without sacrificing compression efficiency.
3Ease of operation
If comfort noise is added at the decoder side using non-standard methods, then natural video appearance is improved, but decoder complexity increases
Solution Approach 1:
The patent performs the comfort noise generation at the encoder side by varying deblocking filter parameters before transmission. This preliminary action embeds the temporal noise characteristics directly into the encoded video stream, eliminating the need for complex non-standard decoder operations and allowing standard decoders to reproduce the natural appearance.
Solution Approach 2:
The encoder side processing creates a copy of the comfort noise effect that can be reproduced by standard decoders using the same deblocking filter parameters. Instead of requiring the decoder to generate complex noise patterns, the encoded parameters enable standard decoders to replicate the natural appearance effect.
4Ease of operation
If film grain characteristics are added using h.264 standard to improve natural appearance, then video realism is improved, but bitrate increases
Solution Approach 1:
The patent merges the comfort noise generation function with the existing deblocking filter operation. By combining temporal noise introduction with the standard deblocking process, the patent achieves video realism enhancement without requiring separate film grain processing streams, thus avoiding additional bitrate overhead.
Solution Approach 2:
The deblocking filter is given a dual function: it performs its standard role of reducing block artifacts while simultaneously introducing temporal comfort noise through parameter variation. This multi-functionality eliminates the need for separate comfort noise processing, maintaining bitrate efficiency while achieving video realism.
Data Source
AI summary
A method of adding comfort noise to a video sequence comprising setting parameters of a deblocking filter of a video encoder to change values during the video sequence, encoding frames of the video sequence using the parameters of the deblocking filter that are set to change values during the video sequence, thereby introducing comfort noise in the video sequence, and including the encoded frames in a bitstream together with an indication of which parameters of the deblocking filter were used when encoding the frames of the video sequence.