Motion Vector Search Apparatus for Video Encoding Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In video encoding systems, when an original motion vector from a first stage is used in a second stage with a different cost function or video signal, the encoding efficiency degrades due to the search being limited to a peripheral area, and the computation cost increases if the search area is extended.
Innovation Solution
A motion vector search apparatus that computes a predicted vector with minimum overhead cost and limits the search area to include both the original and predicted vectors, reducing the number of search points and computation cost by defining a specific geometric area such as circular, elliptic, or rectangular around the original and predicted vectors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the search area is limited to a peripheral area around the original motion vector, then the computation cost is reduced, but the encoding efficiency degrades
Solution Approach 1:
The patent computes the predicted vector in advance using the cost function of the second video encoding system before performing the motion vector search. This preliminary computation allows the search to be focused on a limited area around the predicted vector, reducing computation cost while ensuring the optimal motion vector is found. The predicted vector serves as a guide to position the search area optimally before the actual search begins.
Solution Approach 2:
The patent changes the parameter used to define the search area from being centered on the original motion vector to being centered on the predicted vector. This parameter change allows the search to be performed in a different location that is more likely to contain the optimal motion vector for the second encoding system, thereby maintaining encoding efficiency while keeping the search area limited.
2Reliability
If the search area is extended to ensure finding the optimal motion vector, then the encoding efficiency is improved, but the computation cost increases
Solution Approach 1:
The predicted vector is computed in advance using the second video encoding system's cost function, which provides a starting point that is already optimized for the target system. This preliminary action eliminates the need for extensive searching, as the optimal motion vector is likely to be found in the limited area around this pre-computed predicted vector, thus improving encoding efficiency without significantly increasing computation cost.
Solution Approach 2:
The patent replaces the mechanical approach of performing a wide-area brute-force search with a more intelligent approach that uses cost function evaluation to predict the optimal search area. Instead of mechanically searching all possible vectors, the system uses the predicted vector (derived from cost function analysis) to substitute for extensive mechanical searching, thereby reducing computation cost while maintaining encoding efficiency.
3Use of energy by moving object
If the original motion vector is directly used without re-search, then the computation cost is minimized, but the encoding efficiency degrades due to different cost functions
Solution Approach 1:
The patent performs a preliminary computation of the predicted vector using the second video encoding system's cost function before the actual motion vector search. This preliminary action adapts the search to the specific cost function of the target system, ensuring that the subsequent limited-area search will find an optimal motion vector for that system, thereby maintaining encoding efficiency while keeping computation cost low.
Solution Approach 2:
The patent changes the reference point for the search from the original motion vector (optimized for the first system) to the predicted vector (optimized for the second system's cost function). This parameter change adapts the search to the different cost function environment, allowing the use of a limited search area while still achieving good encoding efficiency in the second system.
Data Source
AI summary
A motion vector search method used in video encoding which performs motion-compensated prediction. The method includes inputting a motion vector which has been searched for with respect to an encoding target block; computing a motion vector having a minimum overhead cost which minimizes the amount of code generated for the motion vector of the encoding target block; limiting a search area based on the input motion vector and the motion vector having the minimum overhead cost; and searching for a motion vector by searching only the limited search area. It is possible to compute a predicted vector of the encoding target block based on a motion vector of an already-encoded block in the vicinity of the target block, and determine the computed predicted vector to be the motion vector having the minimum overhead cost.