[FFmpeg-user] crf mode in libvpx

[Boštjan Strojan]

On Sat, Feb 4, 2012 at 1:44 AM, Carl Eugen Hoyos <cehoyos at ag.or.at> wrote:
> Please test
> ffmpeg -i input -q:v 2 -q:a 100 out.webm
>
> If you have problems, a *reproducible* bug report is very welcome!
>
> Carl Eugen

a.
ffmpeg -i input -strict -2 -q:v 2 -q:a 100 out.webm

returns file (that plays fine everywhere), but has a bitrate of 359
Kbps - (thats for a 1280x720 25fps input) - which suggests that -q:v 2
was probably ignored.

dump:
ffmpeg -i /Users/b/Desktop/test.mov -strict -2 -q:v 2 -q:a 100
/Users/b/Desktop/test.webm
ffmpeg version N-37510-g8c48652 Copyright (c) 2000-2012 the FFmpeg developers
  built on Feb  2 2012 22:02:52 with clang 3.0 (tags/Apple/clang-211.12)
  configuration: --prefix=/Volumes/tempdisk/sw --enable-gpl
--enable-libx264 --enable-libvpx --cc=clang --enable-runtime-cpudetect
  libavutil      51. 37.100 / 51. 37.100
  libavcodec     54.  0.102 / 54.  0.102
  libavformat    54.  0.100 / 54.  0.100
  libavdevice    53.  4.100 / 53.  4.100
  libavfilter     2. 61.100 /  2. 61.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0.  6.100 /  0.  6.100
  libpostproc    52.  0.100 / 52.  0.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/Users/b/Desktop/test.mov':
  Metadata:
    major_brand     : qt
    minor_version   : 537199360
    compatible_brands: qt
    creation_time   : 2010-10-16 10:48:30
  Duration: 00:02:30.44, start: 0.000000, bitrate: 19326 kb/s
    Stream #0:0(eng): Video: prores (apch / 0x68637061), yuv422p10le,
1280x720, 17783 kb/s, SAR 1:1 DAR 16:9, 25 fps, 25 tbr, 25 tbn, 25 tbc
    Metadata:
      creation_time   : 2010-10-16 10:48:30
      handler_name    : ?Apple Alias Data Handler
    Stream #0:1(eng): Audio: pcm_s16le (sowt / 0x74776F73), 48000 Hz,
2 channels, s16, 1536 kb/s
    Metadata:
      creation_time   : 2010-10-16 10:48:30
      handler_name    : ?Apple Alias Data Handler
    Stream #0:2(eng): Data: none (tmcd / 0x64636D74)
    Metadata:
      creation_time   : 2010-10-16 10:48:41
      handler_name    : ?Apple Alias Data Handler
      timecode        : 01:00:00:00
Incompatible pixel format 'yuv422p10le' for codec 'libvpx',
auto-selecting format 'yuv420p'
[buffer @ 0x10d418180] w:1280 h:720 pixfmt:yuv422p10le tb:1/1000000
sar:1/1 sws_param:
[buffersink @ 0x10d4183c0] auto-inserting filter 'auto-inserted scale
0' between the filter 'src' and the filter 'out'
[scale @ 0x10d4187c0] w:1280 h:720 fmt:yuv422p10le -> w:1280 h:720
fmt:yuv420p flags:0x4
[libvpx @ 0x7fa9810b3800] v1.0.0
Output #0, webm, to '/Users/b/Desktop/test.webm':
  Metadata:
    major_brand     : qt
    minor_version   : 537199360
    compatible_brands: qt
    creation_time   : 2010-10-16 10:48:30
    encoder         : Lavf54.0.100
    Stream #0:0(eng): Video: vp8, yuv420p, 1280x720 [SAR 1:1 DAR
16:9], q=-1--1, 200 kb/s, 1k tbn, 25 tbc
    Metadata:
      creation_time   : 2010-10-16 10:48:30
      handler_name    : ?Apple Alias Data Handler
    Stream #0:1(eng): Audio: vorbis, 48000 Hz, 2 channels, s16, 128 kb/s
    Metadata:
      creation_time   : 2010-10-16 10:48:30
      handler_name    : ?Apple Alias Data Handler
Stream mapping:
  Stream #0:0 -> #0:0 (prores -> libvpx)
  Stream #0:1 -> #0:1 (pcm_s16le -> vorbis)
Press [q] to stop, [?] for help
frame=   25 fps=  0 q=0.0 size=       4kB time=00:00:00.04 bitrate=
760.8kbits/s
frame=   41 fps= 40 q=0.0 size=      36kB time=00:00:00.68 bitrate=
430.3kbits/s
frame=   54 fps= 35 q=0.0 size=      68kB time=00:00:01.20 bitrate=
462.3kbits/s
(some lines cut here)
frame= 3724 fps= 28 q=0.0 size=    7884kB time=00:02:28.00 bitrate=
436.4kbits/s
frame= 3735 fps= 28 q=0.0 size=    7916kB time=00:02:28.44 bitrate=
436.9kbits/s
frame= 3750 fps= 28 q=0.0 size=    7948kB time=00:02:29.04 bitrate=
436.9kbits/s
frame= 3761 fps= 28 q=0.0 Lsize=    8028kB time=00:02:30.44 bitrate=
437.1kbits/s

video:3220kB audio:4729kB global headers:3kB muxing overhead 0.944050%

b.
ffmpeg -i file.ogg -i file.webm -acodec copy -vcodec copy -f webm out.webm

seems to output somehow broken out.webm (everytime), external (oggenc
or aotuv oggenc2) or internal vorbis encoder, eternal (vpxenc) or
internal vp8 encoder.

b.