"视频编码优化技术：基于块的全局运动估计与补偿"

运Motion estimation plays a crucial role in video compression algorithms by removing temporal redundancy to enhance coding efficiency. This technique is widely utilized in various international standards such as H.261/263/264 and MPEG-1/2/4. By comparing the current image block with a reference image block to calculate the difference, similar blocks can effectively eliminate temporal redundancy. The greater the similarity between image blocks, the better the efficiency in reducing temporal redundancy. Motion estimation involves estimating and compensating for the motion of objects over time, typically in terms of spatial displacement. Through motion search methods, the most similar blocks are found to determine motion vectors. There are different categories of motion estimation, including global motion estimation, block-based motion estimation, pixel-based motion estimation, region-based motion estimation, and grid-based motion estimation. Global motion estimation considers the overall movement in the entire frame, while block-based motion estimation, which is commonly used due to its simplicity and hardware implementation, matches blocks between frames to estimate motion. This article focuses on block-based motion estimation, which will be referred to as "motion estimation" for brevity. Overall, motion estimation plays a crucial role in video compression by eliminating temporal redundancy and improving coding efficiency. It involves various methods such as block matching, which is widely used for its simplicity and practicality, especially in hardware implementations. Motion estimation is essential for video coding standards and is a key component in achieving high-quality video compression.