[x264-devel] Fwd: x264 rate control

[Jason Garrett-Glaser]

On Fri, Feb 1, 2013 at 2:19 AM, eloise vidal <eloise.vidal at gmail.com> wrote:
> Ok, You're right, it is entirely du to the number of threads, but that does
> not explain me why so few bits are allocated.

If I had to guess, I would say "The predictors at the start haven't
adapted to the video yet, but for some reason, the effect of that
adaptation isn't getting applied until threads finish encoding their
frames, thus making the adaptation window at least as large as the
number of threads. This probably isn't a bug per se (i.e. it's by
design), but of course should be fixed."

Issues like this probably got largely ignored because the main focus
of x264's CBR was broadcast CBR (where the start of the video isn't a big
deal), but they still come up even there, e.g. if there's 20 seconds
of black screen and then the video starts again.

Jason