On Fri, May 29, 2009 at 1:17 PM, Kostya <kostya.shish...@gmail.com> wrote: > On Fri, May 29, 2009 at 12:41:10PM -0400, Alex Converse wrote: >> On Fri, May 29, 2009 at 12:00 AM, Kostya <kostya.shish...@gmail.com> wrote: >> > >> > On Thu, May 28, 2009 at 05:53:51PM -0400, Alex Converse wrote: >> > > Hi, >> > > >> > > This patch seems to vastly improve HCB selection in the AAC encoder. >> > > The screenshot demonstrates its results. (out-1 is before, out-2 is >> > > after, chunk is input) >> > > >> > > Regards, >> > > Alex Converse >> > >> > I believe it does, the question is why? >> > I see two changes - in codebook selection (which does the same thing >> > on the first glance) and in its traversal. >> >> The first chunk of the new code iterates over each stage (swb) and >> figures out the total cost to get to each state (hcb) by staying in >> that state from the previous stage and by transitioning to that state >> from the lowest cost state of the previous stage. >> >> The old code seems to also iterate over each chunk and figures out the >> cost to get to each state (hcb) by staying in that state from the >> previous stage then it seems to compute, as it's alternate cost, the >> cost of navigating to that state in the previous stage plus the cost >> of the lowest cost stage of *this state* (including run increase >> penalties but not the navigation cost). If that cost is lower, we mark >> it as a transition from the lowest cost state this stage. That second >> quantity and how it is handled doesn't seem to make a lot of sense. > > Indeed, so that was my error. > >> > Does the second part fix some bug, simple ineffectiveness or simply >> > needed for changed codebook selection scheme? >> > >> >> The second part simply walks us back to the proper place to look at >> the previous state on a run > 1. It's hard to evaluate on it's own >> since the old code it interfaced with doesn't make a lot of sense. > > Apply as single patch then. >
Applied > [...] --Alex _______________________________________________ FFmpeg-soc mailing list FFmpeg-soc@mplayerhq.hu https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-soc
