U-pattern Video Scan for Memory Bandwidth Optimization

The patent inverts the traditional raster scan pattern by implementing a U-pattern scan that processes macroblocks in a non-linear sequence (e.g., 0, 2, 1, 4, 3, 5...). This inversion allows search windows of spatially adjacent macroblocks to overlap more effectively in the scan order, enabling better cache utilization and reduced memory bandwidth requirements while maintaining encoding simplicity through the systematic reordering of the scan pattern.

The U-pattern scan pattern performs preliminary organization of macroblock processing order to maximize search window overlap before actual motion estimation begins. By pre-establishing the scan sequence that ensures adjacent macroblocks in the U-pattern have overlapping search regions, the system prepares the data access pattern in advance, enabling efficient cache utilization and reducing peak memory bandwidth requirements for high-definition video processing.

The patent changes the scanning pattern parameter from traditional raster scan to U-pattern scan, which fundamentally alters the access sequence of macroblocks. This parameter change in the scan pattern enables the same cache size to achieve higher data re-use efficiency by ensuring that search windows of consecutively processed macroblocks overlap, thereby maximizing cache hit rates without requiring any increase in cache capacity or system cost.