[FFmpeg-user] Speed differences, was: The Magic Microsecond

[Michael Bradshaw]

On Sun, Jul 8, 2012 at 2:13 PM, Jan Ehrhardt <phpdev at ehrhardt.nl> wrote:
> Mike F in gmane.comp.video.ffmpeg.user (Sun, 8 Jul 2012 09:34:33 -0700 (PDT)):
>
>>I see 5 fps difference.. ~ 1% slower
>
> Closing in. On Windows 0.10.2, 0.10.4 & 0.11.1 all have more or less the
> same speed.
>
> ffmpeg version 0.10.4
>   built on Jul  8 2012 21:26:30 with gcc 4.6.2
> frame= 6012 fps=376 q=24.4 Lsize=   12813kB time=00:04:00.48
>         bitrate= 436.5kbits/s
>
> ffmpeg version 0.11.1
>   built on Jul  8 2012 21:48:15 with gcc 4.6.2
> frame= 6012 fps=376 q=24.4 Lsize=   12813kB time=00:04:00.48
>         bitrate= 436.5kbits/s
>
> ffmpeg version 0.11.1.git
>   built on Jul  8 2012 20:43:35 with gcc 4.6.2
> frame= 6012 fps=311 q=24.4 Lsize=   12813kB time=00:04:00.48
>         bitrate= 436.5kbits/s
>
> 376 fps versus 311 fps. The same 20% difference.
> Are there any milestones in between 0.11.1 and the trunk, that
> I can test?

Not that I know of, but if you're willing, you can do a git bisect
between two versions (pick the two revisions that are closest to each
other but still show the significant speed difference) and you can
find out which patch caused the slowdown.

--Michael