1. H.264 Motion Estimation with PLX Joe Halfen Neil Hockert

2. Motivation, why ME? Lots of parallel opportunities to exploit in Motion Estimation. Faster computation through parallels -> more exhaustive searches-> better compression->higher quality at same bit rates Actual speed up is required for things like Video Conferencing In general, the computation complexity of Motion Estimation is from 50% to 90% of a typical video coding system

3. Motivation, why PLX? Full subword parallelism Large amount of data parallelism Frequent use of low-precision data Word size scalability Allows increased operation parallelism and hence increased performance at a potentially lower cost. Allows for PLX implementations to be directly compared in trade off cost comparisons (PLX-32 PLX- 64 PLX-128)

4. Implementation Test a non-parallel assembly level program that runs a given part of the H.264 MV estimation reference software Write a PLX program that implements the source C program by exploiting the parallelisms of Motion Estimation using PLX

5. Challenges Lots of predictive coding used in the given H.264 source code Determining the Mode selection of the source code (SAD, SATD, predictions) The source code is very complex and compact, using lots of calls which limits opportunities to parallelize

6. for (y = 0; y < 4; y++) { refptr = PelYline_11 (ref_pic, abs_y++, abs_x, img_height, img_width); LineSadBlk0 += byte_abs [*refptr++ - *orgptr++]; LineSadBlk1 += byte_abs [*refptr++ - *orgptr++]; LineSadBlk2 += byte_abs [*refptr++ - *orgptr++]; LineSadBlk3 += byte_abs [*refptr++ - *orgptr++]; }