As today's video applications are being requested in many portable end-user devices, and these ones are far
capable of holding and processing large amounts of video data, there is a need for bit rate improvement in
compression algorithms. The objective of this paper is to propose a hardware based post-compression enhancer
situated between the Video Coding Layer and the Network Abstraction Layer of H.264. Our research analyzes
the resulting bit streams produced by the emerging H.264 standard. The goal is to enhance compression rates by
proposing simple post-compression techniques based in symbol's statistics. The CABAC and CAVLC entropy
coders used in H.264 work optimally for 1-bit symbols, and the statistical distribution among them is almost
the best. Our studies reveal that the bit streams presents similar results for 8-bit symbols, and thus a post-compression
using well known byte-based mechanisms will not yield better results; further more, our studies
also show that they even degrade the original compression rate. Nevertheless, a non equally distribution using
6-bits symbols in 2046-bits discrete data packets is found, which can be exploited to boost compression. This
distribution varies between 5.4% for the most probable symbol and 0.98% for the least probable symbol in
average. Again, simple coding a few of the most probable symbols will result in bit rate reduction. A 1-
bit compression enhanced used flag penalty must be introduced for each discrete packet, increasing its size in
0.049%.
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