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.