[FFmpeg-user] libx264 ignores bitrate

Roger Pack rogerdpack2 at gmail.com
Thu Jul 12 19:49:17 CEST 2012


> I try to encode an image sequence to a h264 mp4 file. Whatever I do my
> bitrate is ignored:
> ffmpeg -i audio.mov -i input%05d.jpg -s 1280x720 -b:v 8000k -acodec copy
> -vcodec libx264 output.mov
>
> I tried several things that I found in different blogs (minrates, maxrates).
> But without success.

seems to work here ("bitrate= 282.0kbits/s"):

$ ffmpeg -y -i sintel.mpg -an -vcodec libx264  -b:v 250k  yo.mp4

c:\vids>c:\installs\ffmpeg-20120706-git-8293a21-win32-shared\bin\ffmpeg.exe
-y -i sintel.mpg -an -vcodec libx264  -b:v 250k  yo.mp4
ffmpeg version N-42288-g8293a21 Copyright (c) 2000-2012 the FFmpeg developers
  built on Jul  5 2012 20:58:08 with gcc 4.7.1
  configuration: --disable-static --enable-shared --enable-gpl
--enable-version3 --disable-w32threads --enable-runtime-cpudetect
--enable-avisynth --enable-bzlib --enable-frei0r --enable-libass
--enable-libcelt --enable-libopencore-amrnb --enable-libopencore-amrwb
--enable-libfreetype --enable-libgsm --enable-libmp3lame
--enable-libnut --enable-libopenjpeg --enable-librtmp
--enable-libschroedinger --enable-libspeex --enable-libtheora
--enable-libutvideo --enable-libvo-aacenc --enable-libvo-amrwbenc
--enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs
--enable-libxvid --enable-zlib
  libavutil      51. 64.100 / 51. 64.100
  libavcodec     54. 33.100 / 54. 33.100
  libavformat    54. 15.100 / 54. 15.100
  libavdevice    54.  1.100 / 54.  1.100
  libavfilter     3.  0.101 /  3.  0.101
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0. 15.100 /  0. 15.100
  libpostproc    52.  0.100 / 52.  0.100
[mpeg2video @ 02065920] ac-tex damaged at 40 7
[mpeg2video @ 02065920] Warning MVs not available
[mpeg2video @ 02065920] concealing 1035 DC, 1035 AC, 1035 MV errors
[mpeg @ 0049faa0] max_analyze_duration 5000000 reached at 5024000
Input #0, mpeg, from 'sintel.mpg':
  Duration: 00:14:47.58, start: 0.233367, bitrate: 4132 kb/s
    Stream #0:0[0x1e0]: Video: mpeg2video (Main), yuv420p, 720x480
[SAR 32:27 DAR 16:9], 7000 kb/s, 29.97 fps, 29.97 tbr, 90k tbn, 59.94
tbc
    Stream #0:1[0x80]: Audio: ac3, 48000 Hz, 5.1(side), s16, 448 kb/s
[graph 0 input from stream 0:0 @ 02473020] w:720 h:480 pixfmt:yuv420p
tb:1/90000 fr:30000/1001 sar:32/27 sws_param:flags=2
[output stream 0:0 @ 02473280] No opaque field provided
[libx264 @ 02065fc0] using SAR=32/27
[libx264 @ 02065fc0] using cpu capabilities: MMX2 SSE2Slow SlowCTZ
[libx264 @ 02065fc0] profile High, level 3.0
[libx264 @ 02065fc0] 264 - core 125 r2200 999b753 - H.264/MPEG-4 AVC
codec - Copyleft 2003-2012 - http://www.videolan.org/x264.html -
options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7
psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1
8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2
threads=3 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1
interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2
b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250
keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=abr
mbtree=1 bitrate=250 ratetol=1.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4
ip_ratio=1.40 aq=1:1.00
Output #0, mp4, to 'yo.mp4':
  Metadata:
    encoder         : Lavf54.15.100
    Stream #0:0: Video: h264 ([33][0][0][0] / 0x0021), yuv420p,
720x480 [SAR 32:27 DAR 16:9], q=-1--1, 250 kb/s, 30k tbn, 29.97 tbc
Stream mapping:
  Stream #0:0 -> #0:0 (mpeg2video -> libx264)
Press [q] to stop, [?] for help
[mpeg2video @ 02065920] ac-tex damaged at 40 7
[mpeg2video @ 02065920] Warning MVs not available
[mpeg2video @ 02065920] concealing 1035 DC, 1035 AC, 1035 MV errors
frame= 1768 fps= 28 q=41.0 size=    1975kB time=00:00:57.35 bitrate=
282.0kbits/s dup=159 drop=0


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