Last Coefficient Position Coding with Shared Scan Statistics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current video coding techniques face inefficiencies in coding last significant coefficient position information, leading to increased complexity and bitrates due to the need for separate statistics for each scanning order, which results in reduced coding efficiency and increased system complexity.
Innovation Solution
The techniques involve coding x- and y-coordinates indicating the position of the last significant coefficient based on a scanning order, using common statistics for symmetrical scanning orders, and updating these statistics to improve accuracy, allowing for context adaptive entropy coding that reduces system complexity and bitrates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If separate statistics are maintained for each scanning order, then coding accuracy for last significant coefficient position is improved, but system complexity and bitrate increase
Solution Approach 1:
The patent merges the statistics for symmetrical scanning orders (horizontal and vertical) into a single shared statistics structure. Instead of maintaining separate statistics for each scanning order, the encoder and decoder use common statistics that are updated based on the actual scanning order used, thereby reducing system complexity while maintaining coding accuracy.
Solution Approach 2:
The statistics structure is designed to be universal and multi-functional, serving both horizontal and vertical scanning orders simultaneously. The same statistics can be used for coding last significant coefficient position information regardless of which scanning order is applied, making the system more efficient without sacrificing precision.
2Measurement precision
If separate statistics are maintained for each scanning order, then coding accuracy for last significant coefficient position is improved, but bitrate increases
Solution Approach 1:
By merging the statistics for symmetrical scanning orders into a single shared structure, the patent reduces the amount of side information that needs to be transmitted. The encoder signals fewer statistics parameters to the decoder, thereby reducing bitrate while maintaining the ability to accurately code last significant coefficient position information for both horizontal and vertical scanning orders.
3Device complexity
If common statistics are used for symmetrical scanning orders, then system complexity and bitrate are reduced, but coding accuracy may be compromised
Solution Approach 1:
The patent implements a dynamic approach where the common statistics are adaptively updated based on the actual scanning order used for each block. The encoder and decoder track which scanning order is applied and use this information to appropriately update and interpret the shared statistics, ensuring coding accuracy is maintained despite using common statistics for both symmetrical scanning orders.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
In one example, an apparatus is disclosed for coding coefficients associated with a block of video data during a video coding process, wherein the apparatus includes a video coder configured to code x- and y-coordinates that indicate a position of a last non-zero coefficient within the block according to a scanning order associated with the block when the scanning order comprises a first scanning order, and code interchanged x- and y-coordinatcs that indicate the position of the last non-zero coefficient within the block according to the scanning order when the scanning order comprises a second scanning order, wherein the second scanning order is different than the first scanning order.