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

[Jan Ehrhardt]

Michael Bradshaw in gmane.comp.video.ffmpeg.user (Sun, 8 Jul 2012 17:14:57 -0600):
>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.

The delay was introduced in between 20120622-git-c17808c and
20120627-git-b536e2f. Four lines in the output differ
substantially:

ffmpeg-20120622-git-c17808c -i %input% -vf scale=384:288 -aspect 4:3
	-sws_flags bicubic -vcodec wmv2 -b:v 320k -acodec wmav2 -ab 64k
	-ar 44100 -y output.wmv

[buffer @ 022399e0] w:352 h:288 pixfmt:yuv420p tb:1/90000 fr:25/1
	sar:12/11 sws_param:flags=2
[ffmpeg_buffersink @ 02239c60] No opaque field provided
[Parsed_scale_0 @ 0426d1e0] w:352 h:288 fmt:yuv420p sar:12/11 -> w:384
	h:288 fmt:yuv420p sar:1/1 flags:0x4
[aformat @ 02310ca0] auto-inserting filter 'auto-inserted resampler 0'
	between the filter 'Parsed_anull_0' and the filter 'aformat'

fps: 562

versus

ffmpeg-20120627-git-b536e2f -i %input% -vf scale=384:288 -aspect 4:3
	-sws_flags bicubic -vcodec wmv2 -b:v 320k -acodec wmav2 -ab 64k
	-ar 44100 -y output.wmv

[graph 0 input from stream 0:0 @ 03704c60] w:352 h:288 pixfmt:yuv420p
	tb:1/90000 fr:25/1 sar:12/11 sws_param:flags=2
[output stream 0:0 @ 0036d840] No opaque field provided
[Parsed_scale_0 @ 03704b40] w:352 h:288 fmt:yuv420p sar:12/11 -> w:384
	h:288 fmt:yuv420p sar:1/1 flags:0x4
[graph 1 input from stream 0:1 @ 03791ec0] tb:1/90000 samplefmt:s16
	samplerate:48000 chlayout:0x3

fps: 450

There were a lot of patches between 20120622 and 20120627 ...

Jan



ffmpeg version N-41843-gc17808c Copyright (c) 2000-2012 the FFmpeg developers
  built on Jun 22 2012 17:40:07 with gcc 4.7.1
  configuration: --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. 61.100 / 51. 61.100
  libavcodec     54. 29.100 / 54. 29.100
  libavformat    54. 11.100 / 54. 11.100
  libavdevice    54.  0.100 / 54.  0.100
  libavfilter     2. 82.100 /  2. 82.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0. 15.100 /  0. 15.100
  libpostproc    52.  0.100 / 52.  0.100
[mpeg @ 0240c8e0] max_analyze_duration 5000000 reached at 5000000
Input #0, mpeg, from '/SD_VIDEO/MOV001.MOD':
  Duration: 00:04:00.44, start: 0.919744, bitrate: 1732 kb/s
    Stream #0:0[0x1e0]: Video: mpeg2video (Main), yuv420p, 352x288 [SAR 12:11 DAR 4:3], 3000 kb/s, 25 fps, 25 tbr, 90k tbn, 50 tbc
    Stream #0:1[0x80]: Audio: ac3, 48000 Hz, stereo, s16, 128 kb/s
[buffer @ 022399e0] w:352 h:288 pixfmt:yuv420p tb:1/90000 fr:25/1 sar:12/11 sws_param:flags=2
[ffmpeg_buffersink @ 02239c60] No opaque field provided
[Parsed_scale_0 @ 0426d1e0] w:352 h:288 fmt:yuv420p sar:12/11 -> w:384 h:288 fmt:yuv420p sar:1/1 flags:0x4
[aformat @ 02310ca0] auto-inserting filter 'auto-inserted resampler 0' between the filter 'Parsed_anull_0' and the filter 'aformat'
[auto-inserted resampler 0 @ 02310dc0] chl:stereo fmt:s16 r:48000Hz -> chl:stereo fmt:s16 r:44100Hz
Output #0, asf, to 'output.wmv':
  Metadata:
    WM/EncodingSettings: Lavf54.11.100
    Stream #0:0: Video: wmv2 (WMV2 / 0x32564D57), yuv420p, 384x288 [SAR 1:1 DAR 4:3], q=2-31, 320 kb/s, 1k tbn, 25 tbc
    Stream #0:1: Audio: wmav2 (a[1][0][0] / 0x0161), 44100 Hz, stereo, s16, 63 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (mpeg2video -> wmv2)
  Stream #0:1 -> #0:1 (ac3 -> wmav2)
Press [q] to stop, [?] for help
[mpeg2video @ 02225b80] warning: first frame is no keyframe
frame=  274 fps=0.0 q=6.8 size=     748kB time=00:00:10.68 bitrate= 573.3kbits/s    
frame=  571 fps=555 q=18.9 size=    1394kB time=00:00:22.56 bitrate= 506.1kbits/s    
frame=  863 fps=559 q=17.8 size=    1966kB time=00:00:34.32 bitrate= 469.3kbits/s    
frame= 1147 fps=557 q=16.1 size=    2510kB time=00:00:45.74 bitrate= 449.5kbits/s    
frame= 1439 fps=559 q=9.3 size=    3063kB time=00:00:57.35 bitrate= 437.5kbits/s    
frame= 1720 fps=558 q=9.5 size=    3610kB time=00:01:08.59 bitrate= 431.2kbits/s    
frame= 2008 fps=559 q=9.2 size=    4182kB time=00:01:20.10 bitrate= 427.7kbits/s    
frame= 2298 fps=559 q=11.0 size=    4741kB time=00:01:31.71 bitrate= 423.5kbits/s    
frame= 2585 fps=559 q=13.5 size=    5307kB time=00:01:43.23 bitrate= 421.1kbits/s    
frame= 2865 fps=557 q=10.5 size=    5866kB time=00:01:54.38 bitrate= 420.1kbits/s    
frame= 3142 fps=556 q=12.7 size=    6398kB time=00:02:05.48 bitrate= 417.7kbits/s    
frame= 3428 fps=556 q=10.3 size=    6948kB time=00:02:16.90 bitrate= 415.7kbits/s    
frame= 3722 fps=557 q=10.3 size=    7535kB time=00:02:28.65 bitrate= 415.2kbits/s    
frame= 4018 fps=559 q=16.7 size=    8107kB time=00:02:40.44 bitrate= 413.9kbits/s    
frame= 4310 fps=559 q=10.3 size=    8663kB time=00:02:52.24 bitrate= 412.0kbits/s    
frame= 4606 fps=560 q=9.7 size=    9232kB time=00:03:03.94 bitrate= 411.1kbits/s    
frame= 4904 fps=561 q=15.0 size=    9810kB time=00:03:15.97 bitrate= 410.1kbits/s    
frame= 5195 fps=562 q=10.4 size=   10369kB time=00:03:27.63 bitrate= 409.1kbits/s    
frame= 5494 fps=563 q=12.3 size=   10960kB time=00:03:39.47 bitrate= 409.1kbits/s    
frame= 5788 fps=563 q=10.8 size=   11516kB time=00:03:51.27 bitrate= 407.9kbits/s    
frame= 6012 fps=565 q=21.2 Lsize=   11968kB time=00:04:00.46 bitrate= 407.7kbits/s    

video:9692kB audio:1876kB subtitle:0 global headers:0kB muxing overhead 3.456574%


ffmpeg version N-41975-gb536e2f Copyright (c) 2000-2012 the FFmpeg developers
  built on Jun 26 2012 20:32:54 with gcc 4.7.1
  configuration: --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. 63.100 / 51. 63.100
  libavcodec     54. 29.101 / 54. 29.101
  libavformat    54. 11.100 / 54. 11.100
  libavdevice    54.  0.100 / 54.  0.100
  libavfilter     3.  0.100 /  3.  0.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0. 15.100 /  0. 15.100
  libpostproc    52.  0.100 / 52.  0.100
[mpeg @ 0036c8e0] max_analyze_duration 5000000 reached at 5000000
Input #0, mpeg, from '/SD_VIDEO/MOV001.MOD':
  Duration: 00:04:00.44, start: 0.919744, bitrate: 1732 kb/s
    Stream #0:0[0x1e0]: Video: mpeg2video (Main), yuv420p, 352x288 [SAR 12:11 DAR 4:3], 3000 kb/s, 25 fps, 25 tbr, 90k tbn, 50 tbc
    Stream #0:1[0x80]: Audio: ac3, 48000 Hz, stereo, s16, 128 kb/s
[graph 0 input from stream 0:0 @ 03704c60] w:352 h:288 pixfmt:yuv420p tb:1/90000 fr:25/1 sar:12/11 sws_param:flags=2
[output stream 0:0 @ 0036d840] No opaque field provided
[Parsed_scale_0 @ 03704b40] w:352 h:288 fmt:yuv420p sar:12/11 -> w:384 h:288 fmt:yuv420p sar:1/1 flags:0x4
[graph 1 input from stream 0:1 @ 03791ec0] tb:1/90000 samplefmt:s16 samplerate:48000 chlayout:0x3
[auto-inserted resampler 0 @ 03792040] chl:stereo fmt:s16 r:48000Hz -> chl:stereo fmt:s16 r:44100Hz
Output #0, asf, to 'output.wmv':
  Metadata:
    WM/EncodingSettings: Lavf54.11.100
    Stream #0:0: Video: wmv2 (WMV2 / 0x32564D57), yuv420p, 384x288 [SAR 1:1 DAR 4:3], q=2-31, 320 kb/s, 1k tbn, 25 tbc
    Stream #0:1: Audio: wmav2 (a[1][0][0] / 0x0161), 44100 Hz, stereo, s16, 63 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (mpeg2video -> wmv2)
  Stream #0:1 -> #0:1 (ac3 -> wmav2)
Press [q] to stop, [?] for help
[mpeg2video @ 036a5b80] warning: first frame is no keyframe
frame=  215 fps=0.0 q=7.5 size=     598kB time=00:00:08.40 bitrate= 582.4kbits/s    
frame=  442 fps=429 q=10.3 size=    1141kB time=00:00:17.41 bitrate= 536.9kbits/s    
frame=  671 fps=437 q=8.7 size=    1591kB time=00:00:26.65 bitrate= 489.0kbits/s    
frame=  907 fps=442 q=18.8 size=    2038kB time=00:00:36.03 bitrate= 463.3kbits/s    
frame= 1132 fps=441 q=18.6 size=    2476kB time=00:00:45.04 bitrate= 450.2kbits/s    
frame= 1361 fps=442 q=13.5 size=    2907kB time=00:00:54.19 bitrate= 439.4kbits/s    
frame= 1587 fps=442 q=27.5 size=    3351kB time=00:01:03.20 bitrate= 434.3kbits/s    
frame= 1805 fps=441 q=11.4 size=    3779kB time=00:01:11.93 bitrate= 430.3kbits/s    
frame= 2033 fps=441 q=9.7 size=    4232kB time=00:01:21.08 bitrate= 427.6kbits/s    
frame= 2267 fps=443 q=10.6 size=    4691kB time=00:01:30.51 bitrate= 424.6kbits/s    
frame= 2507 fps=445 q=10.8 size=    5160kB time=00:01:40.07 bitrate= 422.4kbits/s    
frame= 2734 fps=445 q=10.1 size=    5604kB time=00:01:49.13 bitrate= 420.6kbits/s    
frame= 2974 fps=446 q=10.4 size=    6063kB time=00:01:58.70 bitrate= 418.4kbits/s    
frame= 3199 fps=446 q=14.0 size=    6504kB time=00:02:07.75 bitrate= 417.0kbits/s    
frame= 3431 fps=447 q=10.3 size=    6951kB time=00:02:17.13 bitrate= 415.2kbits/s    
frame= 3665 fps=448 q=10.5 size=    7416kB time=00:02:26.37 bitrate= 415.1kbits/s    
frame= 3904 fps=449 q=10.5 size=    7882kB time=00:02:35.94 bitrate= 414.0kbits/s    
frame= 4135 fps=449 q=24.5 size=    8316kB time=00:02:45.14 bitrate= 412.5kbits/s    
frame= 4369 fps=449 q=21.5 size=    8782kB time=00:02:54.56 bitrate= 412.1kbits/s    
frame= 4585 fps=448 q=7.5 size=    9188kB time=00:03:03.20 bitrate= 410.8kbits/s    
frame= 4817 fps=449 q=15.8 size=    9638kB time=00:03:12.44 bitrate= 410.3kbits/s    
frame= 5053 fps=449 q=8.5 size=   10091kB time=00:03:21.92 bitrate= 409.4kbits/s    
frame= 5290 fps=450 q=9.4 size=   10560kB time=00:03:31.30 bitrate= 409.4kbits/s    
frame= 5525 fps=450 q=14.1 size=   11013kB time=00:03:40.77 bitrate= 408.6kbits/s    
frame= 5755 fps=450 q=11.5 size=   11466kB time=00:03:50.01 bitrate= 408.4kbits/s    
frame= 5981 fps=450 q=10.8 size=   11891kB time=00:03:59.07 bitrate= 407.5kbits/s    
frame= 6012 fps=450 q=21.2 Lsize=   11968kB time=00:04:00.46 bitrate= 407.7kbits/s    

video:9692kB audio:1876kB subtitle:0 global headers:0kB muxing overhead 3.456574%