Efficient architecture for global elimination algorithm for H.264 motion estimation

Abstract

This paper presents a fast block matching motion esti mation algorithm and its architecture. The proposed architecture is based on Global Elimination (GE) Algorithm, which uses pixel averaging to reduce complexity of motion search while keeping performance close to that of full search. GE uses a preprocessing stage which can skip unnecessary Sum Absolute Difference (SAD) calculations by comparing minimum SAD with sub-sampled SAD (SSAD). In the second stage SAD is computed at roughly matched candidate positions. GE algorithm uses fixed sub-block sizes and shapes to compute SSAD values in preprocessing stage. Complexity of this GE algorithm is further reduced by adaptively changing the sub-block sizes depending on the macro-block features. In this paper adaptive Global Elimination algorithm has been implemented which reduces the computational complexity of motion estimation algorithm and thus resulted in low power dissipation. Proposed architecture achieved 60% less number of computations compared to existing full search architecture and 50% high throughput compared to existing fixed Global Elimination Architecture.