Matrices are tuned for a certain compressibility. In regions where the codec assigns less bit, the compressibility is usually higher. So, in static scenes, even if the bitrate gets lower, it doesnt mean the codec is using higher quantizers. It's usually the opposite... However when i made AVC-HR i took into account the possibility to set the bitrate variability from "1" to "inf" and the HR matrix should behave correctly (at least in my tests it proved to do it).
It's all a matter of coefficients scaling... for example if the scaling is too "harsh" it will produce artifacts at lower bitrates (too much difference between quants).
Last edited by Sharktooth; 18th August 2005 at 13:42.
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