Tuning the M-coder to improve Dirac’s Entropy Coding
نویسندگان
چکیده
The Dirac codec is a new prototype video coding algorithm from BBC R&D based on wavelet technology. Compression-wise the algorithm is broadly competitive with the state-of-the-art video codecs but computational-wise the execution time is currently poor. One of the largest bottlenecks is the arithmetic coder. Hence we took this part under investigation and replaced it with a faster variant, the M-coder, that is also used in the H.264/AVC codec. This resulted in a convincing speedup. Using a faster (read ‘simpler’) coder has of course an impact on the compression performance. But because we wisely profiled Dirac’s entropy coding statistics and tuned the initialisation and adaptation parameters the impact on the compression is very limited. Key-Words: Dirac video codec, arithmetic coding, M-coder
منابع مشابه
Speeding up Dirac’s Entropy Coder
The Dirac codec is a new prototype video coding algorithm from BBC R&D based on wavelet technology. Compression-wise the algorithm is broadly competitive with the state-of-the-art video codecs but computational-wise the execution time is currently poor. One of the large bottlenecks is the arithmetic coder. Hence we took this part under investigation and replaced it with a faster variant, the M-...
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