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• 2011 In Open Source Multimedia

  5 janvier 2012, par Multimedia Mike — Open Source Multimedia

  Sometimes I think that the pace of multimedia technology is slowing down. Obviously, I’m not paying close enough attention. I thought I would do a little 2011 year-end review of what happened in the world of open source multimedia, mainly for my own benefit. Let me know in the comments what I missed.

  The Split
  The biggest deal in open source multimedia was the matter of the project split. Where once stood one project (FFmpeg) there now stands two (also Libav). Where do things stand with the projects now ? Still very separate but similar. Both projects obsessively monitor each other’s git commits and prodigiously poach each other’s work, both projects being LGPL and all. Most features that land in one code base end up in the other. Thus, I refer to FFmpeg and Libav collectively as “the projects”.

  Some philosophical reasons for the split included project stagnation and development process friction. Curiously, these problems are fond memories now and the spirit of competition has pushed development forward at a blinding pace.

  People inside the project have strong opinions about the split ; that’s understandable. People outside the project have strong opinions about the split ; that’s somewhat less understandable, but whatever. After 5 years of working for Adobe on the Flash Player (a.k.a. the most hated software in all existence if internet nerds are to be believed on the matter), I’m so over internet nerd drama.

  For my part, I just try to maintain some appearance of neutrality since I manage some shared resources for the open source multimedia community (like the wiki and samples repo) and am trying to keep them from fracturing as well.

  Apple and Open Source
  It was big news that Apple magnanimously open sourced their lossless audio codec. That sets a great example and precedent.

  New Features
  I mined the 'git log' of the projects in order to pick out some features that were added during 2011.

  First off, Apple’s ProRes video codec was reverse engineered and incorporated into the multimedia libraries. And for some weird reason, this is an item that made the rounds in the geek press. I’m not entirely sure why, but it may have something to do with inter-project conflict. Anyway, here is the decoder in action, playing a video of some wild swine, one of the few samples we have :

  
  
  

  Other new video codecs included a reverse engineered Indeo 4 decoder. Gotta catch ‘em all ! That completes our collection of Indeo codecs. But that wasn’t enough– this year, we got a completely revised Indeo 3 decoder (the previous one, while functional, exhibited a lot of code artifacts betraying a direct ASM ->C translation). Oh, and many thanks to Kostya for this gem :

  
  
  

  That’s the new Origin Xan decoder (best known for Wing Commander IV cinematics) in action, something I first started reverse engineering back in 2002. Thanks to Kostya for picking up my slack yet again.

  Continuing with the codec section, there is a decoder for Adobe Flash Screen Video 2 — big congrats on this ! One of my jobs at Adobe was documenting this format to the outside world and I was afraid I could never quite make it clear enough to build a complete re-implementation. But the team came through.

  Let’s see, there are decoders for VBLE video, Ut Video, Windows Media Image (WMVP/WMP2), Bink audio version ‘b’, H.264 4:2:2 intra frames, and MxPEG video. There is a DPX image encoder, a Cirrus Logic AccuPak video encoder, and a v410 codec.

  How about some more game stuff ? The projects saw — at long last — an SMJPEG demuxer. This will finally allow usage and testing of the SMJPEG IMA ADPCM audio decoder I added about a decade ago. Funny story behind that– I was porting all of my decoders from xine which included the SMJPEG ADPCM. I just never quite got around to writing a corresponding demuxer. Thanks to Paul Mahol for taking care of that.

  Here’s a DFA playback system for a 1995 DOS CD-ROM title called Chronomaster. No format is too obscure, nor its encoded contents too cheesy :

  
  
  

  There’s now a demuxer for a format called XMV that was (is ?) prevalent on Xbox titles. Now the projects can handle FMV files from many Xbox games, such as Thrillville.

  
  
  

  The projects also gained the ability to play BMV files. I think this surfing wizard comes from Discworld II. It’s non-computer-generated animation at a strange resolution.

  
  
  

  More demuxers : xWMA, PlayStation Portable PMP format, and CRI ADX format ; muxer for OpenMG audio and LATM muxer/demuxer.

  One more thing : an AVX-optimized fast Fourier transform (FFT). If you have a machine that supports AVX, there’s no way you’ll even notice the speed increase of a few measly FFT calls for audio coding/decoding, but that’s hardly the point. The projects always use everything on offer for any CPU.

  Please make me aware of features that I missed in the list !

  Continuous Testing
  As a result of the split, each project has its own FATE server, one for FFmpeg and one for Libav. As of the new year, FFmpeg has just over 1000 tests while Libav had 965. This is one area where I’m obviously ecstatic to see competition. Some ad-hoc measurements on my part indicate that the total code coverage via the FATEs has not appreciably increased. But that’s a total percentage. Both the test count and the code count have been steadily rising.

  Google Summer of Code and Google Code-In
  Once again, the projects were allowed to participate in the Google Summer of Code as well as Google Code-In. I confess that I didn’t keep up with these too carefully (and Code-In is still in progress as of this writing). I do know that the project split occurred after FFmpeg had already been accepted for GSoC season 2011 and the admins were gracious enough to allow FFmpeg and Libav to allow both projects to participate in the same slot as long as they could both be mature about it.

  Happy New Year
  Let’s see what we can accomplish in 2012.

• Anomalie #2472 : Compagnon : un bug dans un des boutons de fermeture

  2 janvier 2012, par Johan .

  En effet, c’est ça. Suis bluffé :-) j’avais : suhosin.get.max_value_length = 512 en le passant à 1000, le bug disparaît. Merci !

• FFMpeg and WebM/VP8

  25 novembre 2011, par Anand Suresh

  I am trying to use ffmpeg and ffserver to stream VP8 video.

  I am using the following command to start FFMpeg :

  ffmpeg -v 9 -loglevel 99 -f x11grab -s 1440x900 -r2 -i :0.0 -f webm http://localhost:8090/feed1.ffm

  The above command abruptly terminates generating the following error :

  > FFmpeg version 0.6.2-4:0.6.2-1ubuntu1.1, Copyright (c) 2000-2010 the Libav developers
  
    built on Sep 16 2011 16:57:46 with gcc 4.5.2
  
    configuration: --extra-version=4:0.6.2-1ubuntu1.1 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --disable-stripping --enable-runtime-cpudetect --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --enable-shared --disable-static
  
    WARNING: library configuration mismatch
  
    libavutil   configuration: --extra-version=4:0.6.2-1ubuntu1.1 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --disable-stripping --enable-runtime-cpudetect --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --shlibdir=/usr/lib/i686/cmov --cpu=i686 --enable-shared --disable-static --disable-ffmpeg --disable-ffplay
  
    libavcodec  configuration: --extra-version=4:0.6.2-1ubuntu1.1 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --disable-stripping --enable-runtime-cpudetect --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --shlibdir=/usr/lib/i686/cmov --cpu=i686 --enable-shared --disable-static --disable-ffmpeg --disable-ffplay
  
    libavformat configuration: --extra-version=4:0.6.2-1ubuntu1.1 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --disable-stripping --enable-runtime-cpudetect --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --shlibdir=/usr/lib/i686/cmov --cpu=i686 --enable-shared --disable-static --disable-ffmpeg --disable-ffplay
  
    libavdevice configuration: --extra-version=4:0.6.2-1ubuntu1.1 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --disable-stripping --enable-runtime-cpudetect --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --shlibdir=/usr/lib/i686/cmov --cpu=i686 --enable-shared --disable-static --disable-ffmpeg --disable-ffplay
  
    libavfilter configuration: --extra-version=4:0.6.2-1ubuntu1.1 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --disable-stripping --enable-runtime-cpudetect --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --shlibdir=/usr/lib/i686/cmov --cpu=i686 --enable-shared --disable-static --disable-ffmpeg --disable-ffplay
  
    libswscale  configuration: --extra-version=4:0.6.2-1ubuntu1.1 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --disable-stripping --enable-runtime-cpudetect --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --shlibdir=/usr/lib/i686/cmov --cpu=i686 --enable-shared --disable-static --disable-ffmpeg --disable-ffplay
  
    libpostproc configuration: --extra-version=4:0.6.2-1ubuntu1.1 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --disable-stripping --enable-runtime-cpudetect --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --shlibdir=/usr/lib/i686/cmov --cpu=i686 --enable-shared --disable-static --disable-ffmpeg --disable-ffplay
  
    libavutil     50.15. 1 / 50.15. 1
  
    libavcodec    52.72. 2 / 52.72. 2
  
    libavformat   52.64. 2 / 52.64. 2
  
    libavdevice   52. 2. 0 / 52. 2. 0
  
    libavfilter    1.19. 0 /  1.19. 0
  
    libswscale     0.11. 0 /  0.11. 0
  
    libpostproc   51. 2. 0 / 51. 2. 0
  
  [x11grab @ 0x9869420]device: :0.0 -> display: :0.0 x: 0 y: 0 width: 1440 height: 900
  
  [x11grab @ 0x9869420]shared memory extension  found
  
  [x11grab @ 0x9869420]Probe buffer size limit 5000000 reached
  
  [x11grab @ 0x9869420]Estimating duration from bitrate, this may be inaccurate
  
  Input #0, x11grab, from ':0.0':
  
    Duration: N/A, start: 1322253753.374957, bitrate: 41472 kb/s
  
      Stream #0.0, 1, 1/1000000: Video: rawvideo, bgra, 1440x900, 1/1, 41472 kb/s, 1 tbr, 1000k tbn, 1 tbc
  
  [libvpx @ 0x9876540]v0.9.6
  
  [libvpx @ 0x9876540]--enable-pic --enable-shared --disable-install-bins --disable-install-srcs --target=x86-linux-gcc
  
  [libvpx @ 0x9876540]vpx_codec_enc_cfg
  
  [libvpx @ 0x9876540]generic settings
  
    g_usage:                      0
  
    g_threads:                    0
  
    g_profile:                    0
  
    g_w:                          320
  
    g_h:                          240
  
    g_timebase:                   {1/30}
  
    g_error_resilient:            0
  
    g_pass:                       0
  
    g_lag_in_frames:              0
  
  [libvpx @ 0x9876540]rate control settings
  
    rc_dropframe_thresh:          0
  
    rc_resize_allowed:            0
  
    rc_resize_up_thresh:          60
  
    rc_resize_down_thresh:        30
  
    rc_end_usage:                 0
  
    rc_twopass_stats_in:          (nil)(0)
  
    rc_target_bitrate:            256
  
  [libvpx @ 0x9876540]quantizer settings
  
    rc_min_quantizer:             4
  
    rc_max_quantizer:             63
  
  [libvpx @ 0x9876540]bitrate tolerance
  
    rc_undershoot_pct:            95
  
    rc_overshoot_pct:             200
  
  [libvpx @ 0x9876540]decoder buffer model
  
    rc_buf_sz:                    6000
  
    rc_buf_initial_sz:            4000
  
    rc_buf_optimal_sz:            5000
  
  [libvpx @ 0x9876540]2 pass rate control settings
  
    rc_2pass_vbr_bias_pct:        50
  
    rc_2pass_vbr_minsection_pct:  0
  
    rc_2pass_vbr_maxsection_pct:  400
  
  [libvpx @ 0x9876540]keyframing settings
  
    kf_mode:                      1
  
    kf_min_dist:                  0
  
    kf_max_dist:                  9999
  
  [libvpx @ 0x9876540]
  
  [libvpx @ 0x9876540]vpx_codec_enc_cfg
  
  [libvpx @ 0x9876540]generic settings
  
    g_usage:                      0
  
    g_threads:                    1
  
    g_profile:                    0
  
    g_w:                          1440
  
    g_h:                          900
  
    g_timebase:                   {1/1}
  
    g_error_resilient:            0
  
    g_pass:                       0
  
    g_lag_in_frames:              0
  
  [libvpx @ 0x9876540]rate control settings
  
    rc_dropframe_thresh:          0
  
    rc_resize_allowed:            0
  
    rc_resize_up_thresh:          60
  
    rc_resize_down_thresh:        30
  
    rc_end_usage:                 0
  
    rc_twopass_stats_in:          (nil)(0)
  
    rc_target_bitrate:            200
  
  [libvpx @ 0x9876540]quantizer settings
  
    rc_min_quantizer:             1
  
    rc_max_quantizer:             38
  
  [libvpx @ 0x9876540]bitrate tolerance
  
    rc_undershoot_pct:            95
  
    rc_overshoot_pct:             200
  
  [libvpx @ 0x9876540]decoder buffer model
  
    rc_buf_sz:                    6000
  
    rc_buf_initial_sz:            4000
  
    rc_buf_optimal_sz:            5000
  
  [libvpx @ 0x9876540]2 pass rate control settings
  
    rc_2pass_vbr_bias_pct:        50
  
    rc_2pass_vbr_minsection_pct:  0
  
    rc_2pass_vbr_maxsection_pct:  400
  
  [libvpx @ 0x9876540]keyframing settings
  
    kf_mode:                      1
  
    kf_min_dist:                  0
  
    kf_max_dist:                  12
  
  [libvpx @ 0x9876540]
  
  [libvpx @ 0x9876540]vpx_codec_control
  
  [libvpx @ 0x9876540]  VP8E_SET_CPUUSED:             3
  
  [libvpx @ 0x9876540]  VP8E_SET_NOISE_SENSITIVITY:   0
  
  Output #0, webm, to 'http://127.0.0.1:8090/feed1.ffm':
  
    Metadata:
  
      encoder         : Lavf52.64.2
  
      Stream #0.0, 0, 1/1000: Video: libvpx, yuv420p, 1440x900, 1/1, q=2-31, 200 kb/s, 1k tbn, 1 tbc
  
  Stream mapping:
  
    Stream #0.0 -> #0.0
  
  Press [q] to stop encoding
  
  [webm @ 0x98753b0]Writing block at offset 15, size 158658, pts 0, dts 0, duration 1000, flags 128
  
  [webm @ 0x98753b0]Starting new cluster at offset 158681 bytes, pts 0

  Can anyone point out what I am doing wrong here ? Why does ffmpeg die everytime it starts a new cluster ?

  Thanks