A Block Motion Compensation Fast Algorithm Designed for RV40 Codec

This paper proposed a whole new design for RV40(realvideo40) video decoder from FFmpeg(fast forward Moving Picture Experts Group),which is in lack of the ability to decode smoothly when decoding a period of high bit rate frames within some video streams. The design specially optimized the sub pixel interpolation algorithm, which is the core of motion compensation. The design uses detailed, different algorithms based on different frame types. Meanwhile a temporal related, flexible algorithm usage method is introduced to deal with the jamming in decoding sequence. The time consumed by calculating is reduced with an acceptable reduced frame appearance. This design is used on a test platform for testify. The result returned shows that this design can greatly promote decoding performance up to 50% while reducing a little picture performance.