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  • Personnaliser en ajoutant son logo, sa bannière ou son image de fond

    5 septembre 2013, par

    Certains thèmes prennent en compte trois éléments de personnalisation : l’ajout d’un logo ; l’ajout d’une bannière l’ajout d’une image de fond ;

  • Participer à sa traduction

    10 avril 2011

    Vous pouvez nous aider à améliorer les locutions utilisées dans le logiciel ou à traduire celui-ci dans n’importe qu’elle nouvelle langue permettant sa diffusion à de nouvelles communautés linguistiques.
    Pour ce faire, on utilise l’interface de traduction de SPIP où l’ensemble des modules de langue de MediaSPIP sont à disposition. ll vous suffit de vous inscrire sur la liste de discussion des traducteurs pour demander plus d’informations.
    Actuellement MediaSPIP n’est disponible qu’en français et (...)

  • MediaSPIP v0.2

    21 juin 2013, par

    MediaSPIP 0.2 est la première version de MediaSPIP stable.
    Sa date de sortie officielle est le 21 juin 2013 et est annoncée ici.
    Le fichier zip ici présent contient uniquement les sources de MediaSPIP en version standalone.
    Comme pour la version précédente, il est nécessaire d’installer manuellement l’ensemble des dépendances logicielles sur le serveur.
    Si vous souhaitez utiliser cette archive pour une installation en mode ferme, il vous faudra également procéder à d’autres modifications (...)

Sur d’autres sites (13098)

  • ffmpeg based app and VLC IPC ?

    1er avril 2012, par ronag

    I have an application that uses the ffmpeg libraries (not ffmpeg.exe) to encode video and would like to forward the encoded data directly to a VLC process.

    Right now I use udp ://localhost (i.e. avio_open("udp://localhost:5290") and vlc udp://@localhost:5290) for interprocess communication, however it seems a bit unreliable.

    ffmpeg (avio_open) doesn't seem to support named pipes, i.e. \\.\pipe\test is not accepted, and I cannot use standard output/input piping since the applications run in different processes.

    Soo my question is, how can I achieve reliable (and somewhat efficient) interprocess communication between VLC and an application using the ffmpeg libraries ?

  • Encode x264 video with ffmpeg for Android with starting offset

    4 août 2013, par scubed

    I'm trying to convert a video to play on an Android device.
    The video is from a big movie. I am chopping it back into pieces
    to correspond with the actual segments of the movie using -ss and -t.

    The input is mp4 with H.264 and AAC.
    The output is mkv using H.264 and Vorbis.

    Specifically, the input is :

    Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p, 320x240, 2240 kb/s, 29.97 fps, 60 tbr, 90k tbn, 180k tbc
    
Stream #0:1(und): Audio: aac (mp4a / 0x6134706D), 48000 Hz, stereo, s16, 162 kb/s

    I'm using : ffmpeg version 1.0.7

    The command I'm trying is something like :

    ffmpeg -ss 00:03:52.000 -i in.mp4 -t 00:01:00.000 -c:v libx264 -preset medium -crf 20 -maxrate 400k -bufsize 1835k -c:a libvorbis -sn out.mkv

    However, while the resulting video works fine on my computer, when I click on
    my phone, it says : Can't play video
    and checking the Android log, it has :

    E/SoftAVC (24319): Decoder failed: -2
    
E/OMXCodec(24319): [OMX.google.h264.decoder] ERROR(0x80001001, -1007)

    It is still able to make a thumbnail for the movie, but not play it.

    Interestingly, some simple variations of that command do work :
    Remove -ss to start at the beginning of the video
    Use -an to disable audio

    These variations still failed :
    Copying the original audio with -c:a copy, or other audio codecs like vorbis, mp3
    Using mp4 instead of mkv
    Using baseline H.264 profile, including restricting level to 1.2.

    Running through mkvmerge first not only fails, but makes Android not able to even make a thumbnail.

    I don't know if it is related, but another small thing I noticed is that for
    starting transcoding later in the movie, the audio starts out slightly out-of-sync.
    After several seconds, it gets back in sync. The audio is in sync in the original.

    Robert Rowntree :

    -vcodec libx264 -b:v 200k -bt 50k -threads 0 -b_strategy 1 -acodec copy -f mp4 -strict -2

    Interesting. Your command almost works. The video actually plays on Android. The one problem is that the audio is out-of-sync and stays out-of-sync throughout the whole clip. But, that's much closer than I've been. I'll search around there and see if I can find the right combination.

    I tried combinations of it. It appears that using both mp4 and copying the audio is what allows it to work. Using libvorbis or going to mkv breaks it again. But, I would like to transcode the audio, and I suspect to keep it in sync, I might have to transcode it anyways. Note that even with transcoding, when I play it back on the computer, I still don't have sync between audio and video.

    LordNeckbeard :
    Here is the complete log.

    ffmpeg version 1.0.7 Copyright (c) 2000-2013 the FFmpeg developers
    
  built on Jul 27 2013 13:01:19 with gcc 4.4.5 (Gentoo 4.4.5 p1.2, pie-0.4.5)
    
  configuration: --prefix=/usr --libdir=/usr/lib64 --shlibdir=/usr/lib64 --mandir=/usr/share/man --enable-shared --cc=x86_64-pc-linux-gnu-gcc --cxx=x86_64-pc-linux-gnu-g++ --ar=x86_64-pc-linux-gnu-ar --optflags='-mtune=athlon64 -O2 -pipe -fomit-frame-pointer -fstack-protector' --extra-cflags='-mtune=athlon64 -O2 -pipe -fomit-frame-pointer -fstack-protector' --extra-cxxflags='-mtune=athlon64 -O2 -pipe -fomit-frame-pointer -fstack-protector' --disable-static --enable-gpl --enable-version3 --enable-postproc --enable-avfilter --enable-avresample --disable-stripping --disable-debug --disable-doc --disable-vaapi --disable-runtime-cpudetect --enable-libmp3lame --enable-libvo-aacenc --enable-libtheora --enable-libx264 --enable-libxvid --enable-libcaca --enable-openal --disable-indev=v4l2 --disable-indev=oss --disable-indev=jack --enable-x11grab --disable-outdev=oss --enable-libfreetype --enable-pthreads --enable-libspeex --enable-libvorbis --disable-altivec --disable-avx --disable-vis --disable-neon --cpu=athlon64 -  libavutil      51. 73.101 / 51. 73.101
    
  libavcodec     54. 59.100 / 54. 59.100
    
  libavformat    54. 29.104 / 54. 29.104
    
  libavdevice    54.  2.101 / 54.  2.101
    
  libavfilter     3. 17.100 /  3. 17.100
    
  libswscale      2.  1.101 /  2.  1.101
    
  libswresample   0. 15.100 /  0. 15.100
    
  libpostproc    52.  0.100 / 52.  0.100
    
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'in.mp4':
    
  Metadata:
    
    major_brand     : mp42
    
    minor_version   : 0
    
    compatible_brands: mp42isomavc1
    
    creation_time   : 2013-07-13 02:23:51
    
    encoder         : HandBrake 0.9.6 2012022800
    
  Duration: 03:14:01.41, start: 0.000000, bitrate: 2408 kb/s
    
    Chapter #0.0: start -0.133467, end 648.697411
    
    Metadata:
    
      title           : Chapter  1
    
    Chapter #0.1: start 648.697411, end 1297.345411
    
    Metadata:
    
      title           : Chapter  2
    
    Chapter #0.2: start 1297.345411, end 1729.777411
    
    Metadata:
    
      title           : Chapter  3
    
    Chapter #0.3: start 1729.777411, end 2378.425411
    
    Metadata:
    
      title           : Chapter  4
    
    Chapter #0.4: start 2378.425411, end 3027.073411
    
    Metadata:
    
      title           : Chapter  5
    
    Chapter #0.5: start 3027.073411, end 3675.721411
    
    Metadata:
    
      title           : Chapter  6
    
    Chapter #0.6: start 3675.721411, end 4108.153411
    
    Metadata:
    
      title           : Chapter  7
    
    Chapter #0.7: start 4108.153411, end 4756.801411
    
    Metadata:
    
      title           : Chapter  8
    
    Chapter #0.8: start 4756.801411, end 5405.449411
    
    Metadata:
    
      title           : Chapter  9
    
    Chapter #0.9: start 5405.449411, end 6054.097411
    
    Metadata:
    
      title           : Chapter 10
    
    Chapter #0.10: start 6054.097411, end 6702.745411
    
    Metadata:
    
      title           : Chapter 11
    
    Chapter #0.11: start 6702.745411, end 7135.177411
    
    Metadata:
    
      title           : Chapter 12
    
    Chapter #0.12: start 7135.177411, end 7783.825411
    
    Metadata:
    
      title           : Chapter 13
    
    Chapter #0.13: start 7783.825411, end 8432.473411
    
    Metadata:
    
      title           : Chapter 14
    
    Chapter #0.14: start 8432.473411, end 9081.121411
    
    Metadata:
    
      title           : Chapter 15
    
    Chapter #0.15: start 9081.121411, end 9513.553411
    
    Metadata:
    
      title           : Chapter 16
    
    Chapter #0.16: start 9513.553411, end 10162.201411
    
    Metadata:
    
      title           : Chapter 17
    
    Chapter #0.17: start 10162.201411, end 10810.849411
    
    Metadata:
    
      title           : Chapter 18
    
    Chapter #0.18: start 10810.849411, end 11459.497411
    
    Metadata:
    
      title           : Chapter 19
    
    Chapter #0.19: start 11459.497411, end 11641.412478
    
    Metadata:
    
      title           : Chapter 20
    
    Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p, 320x240, 2240 kb/s, 29.97 fps, 60 tbr, 90k tbn, 180k tbc
    
    Metadata:
    
      creation_time   : 2013-07-13 02:23:51
    
    Stream #0:1(und): Audio: aac (mp4a / 0x6134706D), 48000 Hz, stereo, s16, 162 kb/s
    
    Metadata:
    
      creation_time   : 2013-07-13 02:23:51
    
    Stream #0:2(und): Subtitle: mov_text (text / 0x74786574)
    
    Metadata:
    
      creation_time   : 2013-07-13 02:23:51
    
[libx264 @ 0x14ea220] using cpu capabilities: MMX2 SSE2Slow SlowCTZ
    
[libx264 @ 0x14ea220] profile High, level 2.1
    
[libx264 @ 0x14ea220] 264 - core 120 - H.264/MPEG-4 AVC codec - Copyleft 2003-2011 - 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 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=60 keyint_min=6 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=20.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 vbv_maxrate=400 vbv_bufsize=1835 crf_max=0.0 nal_hrd=none ip_ratio=1.40 aq=1:1.00
    
Output #0, matroska, to 'out.mkv':
    
  Metadata:
    
    major_brand     : mp42
    
    minor_version   : 0
    
    compatible_brands: mp42isomavc1
    
    encoder         : Lavf54.29.104
    
    Chapter #0.0: start 0.000000, end 60.000000
    
    Metadata:
    
      title           : Chapter  1
    
    Stream #0:0(und): Video: h264 (H264 / 0x34363248), yuv420p, 320x240, q=-1--1, 1k tbn, 60 tbc
    
    Metadata:
    
      creation_time   : 2013-07-13 02:23:51
    
    Stream #0:1(und): Audio: vorbis (oV[0][0] / 0x566F), 48000 Hz, stereo, flt
    
    Metadata:
    
      creation_time   : 2013-07-13 02:23:51
    
Stream mapping:
    
  Stream #0:0 -> #0:0 (h264 -> libx264)
    
  Stream #0:1 -> #0:1 (aac -> libvorbis)
    
Press [q] to stop, [?] for help
    
frame= 1799 fps= 92 q=-1.0 Lsize=    3738kB time=00:00:59.98 bitrate= 510.5kbits/s dup=0 drop=51    =51    
    
video:3016kB audio:683kB subtitle:0 global headers:4kB muxing overhead 0.939943%
    
[libx264 @ 0x14ea220] frame I:31    Avg QP:20.23  size: 14126
    
[libx264 @ 0x14ea220] frame P:634   Avg QP:23.03  size:  3317
    
[libx264 @ 0x14ea220] frame B:1134  Avg QP:27.71  size:   482
    
[libx264 @ 0x14ea220] consecutive B-frames:  2.3% 12.8% 84.7%  0.2%
    
[libx264 @ 0x14ea220] mb I  I16..4:  3.8% 63.8% 32.4%
    
[libx264 @ 0x14ea220] mb P  I16..4:  0.1%  0.3%  0.1%  P16..4: 47.4% 30.2% 19.5%  0.0%  0.0%    skip: 2.4%
    
[libx264 @ 0x14ea220] mb B  I16..4:  0.0%  0.0%  0.0%  B16..8: 35.2%  3.0%  0.6%  direct: 8.8%  skip:52.3%  L0:28.7% L1:63.9% BI: 7.4%
    
[libx264 @ 0x14ea220] 8x8 transform intra:64.0% inter:59.5%
    
[libx264 @ 0x14ea220] coded y,uvDC,uvAC intra: 94.2% 99.5% 95.5% inter: 23.3% 55.5% 14.0%
    
[libx264 @ 0x14ea220] i16 v,h,dc,p: 75% 10%  5% 10%
    
[libx264 @ 0x14ea220] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 19% 16% 12%  8%  7%  8%  8% 11% 11%
    
[libx264 @ 0x14ea220] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 17% 20%  7%  8%  9%  9% 10% 10% 11%
    
[libx264 @ 0x14ea220] i8c dc,h,v,p: 38% 31% 14% 17%
    
[libx264 @ 0x14ea220] Weighted P-Frames: Y:7.3% UV:4.4%
    
[libx264 @ 0x14ea220] ref P L0: 48.8% 14.2% 29.1%  7.5%  0.4%
    
[libx264 @ 0x14ea220] ref B L0: 65.4% 30.8%  3.7%
    
[libx264 @ 0x14ea220] ref B L1: 89.0% 11.0%
    
[libx264 @ 0x14ea220] kb/s:411.70

  • Need explanation of details of ffmpeg and pipes comand

    6 décembre 2011, par Don Nummer Jr

    Got the following from FFmpeg FAQ :

    mkfifo intermediate1.mpg
    
mkfifo intermediate2.mpg
    
ffmpeg -i input1.avi -sameq -y intermediate1.mpg < /dev/null &
    
ffmpeg -i input2.avi -sameq -y intermediate2.mpg < /dev/null &
    
cat intermediate1.mpg intermediate2.mpg |\
    
ffmpeg -f mpeg -i - -sameq -vcodec mpeg4 -acodec libmp3lame output.avi

    Before i use or modify it I would like to understand it completely.

    What does the < /dev/null & do ?

    I understand | is pipe but why |\ ?

    What is the -f mpeg after ffmpeg (Seems, it tells ffmpeg to accept the piped in output from the cat(?) )

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