Early Termination and Block Reordering for H.264 Intra Prediction

This paper presents an H.264 intra frame encoder that processes an HD size (1280x720) video at 30 fps with the operating clock frequency of 47 ㎒. The low clock frequency is achieved by a novel pipeline schedule that employs the early termination of 16x16 prediction by using the cost of 4x4 prediction as the stop condition. In order to allow the early termination, the proposed pipeline modifies the processing order for 4x4 predictions as proposed in [3] For further speed-up, the best 8 modes out of 9 prediction modes are chosen. With the proposed pipeline schedule, 61% of the execution time is saved for intra prediction of HD size videos. As a result, the required execution time is 435 cycles which is about 125 cycles faster than the previous best implementation which performs intra prediction in only 7 modes.