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  • La sauvegarde automatique de canaux SPIP

    1 April 2010, by

    Dans le cadre de la mise en place d’une plateforme ouverte, il est important pour les hébergeurs de pouvoir disposer de sauvegardes assez régulières pour parer à tout problème éventuel.
    Pour réaliser cette tâche on se base sur deux plugins SPIP : Saveauto qui permet une sauvegarde régulière de la base de donnée sous la forme d’un dump mysql (utilisable dans phpmyadmin) mes_fichiers_2 qui permet de réaliser une archive au format zip des données importantes du site (les documents, les éléments (...)

  • D’autres logiciels intéressants

    12 April 2011, by

    On ne revendique pas d’être les seuls à faire ce que l’on fait ... et on ne revendique surtout pas d’être les meilleurs non plus ... Ce que l’on fait, on essaie juste de le faire bien, et de mieux en mieux...
    La liste suivante correspond à des logiciels qui tendent peu ou prou à faire comme MediaSPIP ou que MediaSPIP tente peu ou prou à faire pareil, peu importe ...
    On ne les connais pas, on ne les a pas essayé, mais vous pouvez peut être y jeter un coup d’oeil.
    Videopress
    Site Internet : (...)

  • Encoding and processing into web-friendly formats

    13 April 2011, by

    MediaSPIP automatically converts uploaded files to internet-compatible formats.
    Video files are encoded in MP4, Ogv and WebM (supported by HTML5) and MP4 (supported by Flash).
    Audio files are encoded in MP3 and Ogg (supported by HTML5) and MP3 (supported by Flash).
    Where possible, text is analyzed in order to retrieve the data needed for search engine detection, and then exported as a series of image files.
    All uploaded files are stored online in their original format, so you can (...)

On other websites (4541)

  • iOS Objective C Opus audio stream kAudioFormatOpus — specification / conversion query

    16 April 2022, by deffodeffo

    I'm working on a React Native voice app wanting to record straight to an Opus stream.

    


    On the iOS side at device level, I'm working in Objective C and I'm using an AVAudioSession recorder with formatID set to kAudioFormatOpus. The recorder captures audio data in the specified format and passes packets for upstreaming to the React Native app.

    


    This is all working well and emitting a stream of audio data when I run my code on an iOS Simulator or real device.

    


    My problem is when I receive the audio stream in the backend, I find I'm unable to reliably decode the Opus stream using ffmpeg. (I wish to decode to PCM.)

    


    Whilst I could post up specific code to show what I'm doing in more detail, my question at this stage is more generic in nature:

    


    Is anyone familiar with the format of Opus audio stream that is generated by iOS AudioSession recorder under audio format kAudioFormatOpus ? Is anyone able to suggest proven conversion techniques? (e.g. some ffmpeg commands), or else hook me up with some links to format specs so I can figure out what is going on here ?

    


    The Apple Developer documentation contains zero useful information: https://developer.apple.com/documentation/coreaudiotypes/1572096-audio_data_format_identifiers/kaudioformatopus?changes=la__2&language=objc

    


    I have looked all over the internet, but I'm unable to find any useful spec info that corresponds to the stream that AVAudioSession recorder is outputting. I have seen a few posts which say Apple have not fully complied with the Opus spec, but I don't know enough about the proper structure of Opus to ascertain this for myself.

    


    Any help would be very much appreciated.

    


    Thanks all

    


  • ffplay: how does it calculate the fps for playback?

    21 October 2020, by Daniel

    I'm trying to playback a live media (h264) which is produced by a hardware encoder.

    


    The actual desired FPS on the encoder is set to 20, and when checking the logs of the encoder it prints "FPS statistics" every minute:

    


    2020-10-21 17:26:54.787 [  info] video_stream_thread(),video chn 0, fps: 19.989270
2020-10-21 17:27:54.836 [  info] video_stream_thread(),video chn 0, fps: 19.989270
2020-10-21 17:28:54.837 [  info] video_stream_thread(),video chn 0, fps: 20.005924
2020-10-21 17:29:54.837 [  info] video_stream_thread(),video chn 0, fps: 19.989270
2020-10-21 17:30:54.888 [  info] video_stream_thread(),video chn 0, fps: 19.989274
2020-10-21 17:31:54.918 [  info] video_stream_thread(),video chn 0, fps: 19.989264


    


    You can see it's varying, but not too much around 20.

    


    Question1: Is this normal? Or it should be exactly 20 every time? To avoid confusion: I'd like to know if by the standard of H264, can this be accepted as a valid stream or this violates some
rule?

    


    I'm trying to playback this stream with ffplay:

    


    $ ffplay rtsp://this_stream
Input #0, rtsp, from 'xyz'
  Metadata:
    title           : 
    comment         : substream
  Duration: N/A, start: 0.040000, bitrate: N/A
    Stream #0:0: Video: h264 (Constrained Baseline), yuv420p(progressive), 640x360, 25 fps, 25 tbr, 90k tbn, 180k tbc


    


    The thing is that ffplay thinks this is a stream with 25fps. And it also plays 25 frames each sec, causing the stream to stall and buffer in every few seconds.

    


    I believe the fps is calculated by some pts/dts values in the stream itself, and it's not hardcoded. Am I wrong here?

    


    If I'm not wrong, why does ffplay thinks this stream runs at 25fps, whereas it only runs at (around) 20?

    


  • syncing a video file with audio using ffmpeg is returning a video without audio

    31 July 2019, by abbood

    When I attempt to sync a .mov video with an .m4a audio file using ffmpeg like so

    ffmpeg -ss 00:00:2 -i test.m4a  -i test.mov -c:v copy -c:a aac -strict experimental output.mp4

    it works like a charm. But right now I’ve recorded a usability test video using adobe XD, and it returned an .mp4 (MPEG-4) video and I manually recorded the audio using quicktimre returning a .m4a audio file.

    Trying to merge them using ffmpeg is returning a video without any audio:

    ffmpeg -i video.mp4  -i audio.m4a -c:v copy -c:a aac -strict experimental output.mp4
    
ffmpeg version 4.1 Copyright (c) 2000-2018 the FFmpeg developers
    
  built with Apple LLVM version 10.0.0 (clang-1000.11.45.5)
    
  configuration: --prefix=/usr/local/Cellar/ffmpeg/4.1_1 --enable-shared --enable-pthreads --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-ffplay --enable-gpl --enable-libmp3lame --enable-libopus --enable-libsnappy --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libxvid --enable-lzma --enable-opencl --enable-videotoolbox
    
  libavutil      56. 22.100 / 56. 22.100
    
  libavcodec     58. 35.100 / 58. 35.100
    
  libavformat    58. 20.100 / 58. 20.100
    
  libavdevice    58.  5.100 / 58.  5.100
    
  libavfilter     7. 40.101 /  7. 40.101
    
  libavresample   4.  0.  0 /  4.  0.  0
    
  libswscale      5.  3.100 /  5.  3.100
    
  libswresample   3.  3.100 /  3.  3.100
    
  libpostproc    55.  3.100 / 55.  3.100
    
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'video.mp4':
    
  Metadata:
    
    major_brand     : qt
    
    minor_version   : 0
    
    compatible_brands: qt
    
    creation_time   : 2019-07-31T14:43:18.000000Z
    
    com.apple.quicktime.make: Apple
    
    com.apple.quicktime.model: MacBookPro15,1
    
    com.apple.quicktime.software: Mac OS X 10.14.5 (18F203)
    
    com.apple.quicktime.creationdate: 2019-07-31T17:43:17+0300
    
  Duration: 00:03:46.05, start: 0.000000, bitrate: 498 kb/s
    
    Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv, bt709), 374x812 [SAR 1:1 DAR 187:406], 390 kb/s, 60 fps, 60 tbr, 6k tbn, 12k tbc (default)
    
    Metadata:
    
      creation_time   : 2019-07-31T14:43:18.000000Z
    
      handler_name    : Core Media Video
    
      encoder         : H.264
    
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 8000 Hz, stereo, fltp, 0 kb/s (default)
    
    Metadata:
    
      creation_time   : 2019-07-31T14:43:18.000000Z
    
      handler_name    : Core Media Audio
    
Input #1, mov,mp4,m4a,3gp,3g2,mj2, from 'audio.m4a':
    
  Metadata:
    
    major_brand     : M4A
    
    minor_version   : 0
    
    compatible_brands: M4A mp42isom
    
    creation_time   : 2019-07-31T14:47:26.000000Z
    
    iTunSMPB        :  00000000 00000840 00000000 00000000009DFBC0 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
    
  Duration: 00:03:54.78, start: 0.047891, bitrate: 225 kb/s
    
    Stream #1:0(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, mono, fltp, 224 kb/s (default)
    
    Metadata:
    
      creation_time   : 2019-07-31T14:47:26.000000Z
    
      handler_name    : Core Media Audio
    
Stream mapping:
    
  Stream #0:0 -> #0:0 (copy)
    
  Stream #0:1 -> #0:1 (aac (native) -> aac (native))
    
Press [q] to stop, [?] for help
    
[aac @ 0x7fb5a4806a00] Too many bits 16384.000000 > 12288 per frame requested, clamping to max
    
Output #0, mp4, to 'output.mp4':
    
  Metadata:
    
    major_brand     : qt
    
    minor_version   : 0
    
    compatible_brands: qt
    
    com.apple.quicktime.creationdate: 2019-07-31T17:43:17+0300
    
    com.apple.quicktime.make: Apple
    
    com.apple.quicktime.model: MacBookPro15,1
    
    com.apple.quicktime.software: Mac OS X 10.14.5 (18F203)
    
    encoder         : Lavf58.20.100
    
    Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv, bt709), 374x812 [SAR 1:1 DAR 187:406], q=2-31, 390 kb/s, 60 fps, 60 tbr, 12k tbn, 6k tbc (default)
    
    Metadata:
    
      creation_time   : 2019-07-31T14:43:18.000000Z
    
      handler_name    : Core Media Video
    
      encoder         : H.264
    
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 8000 Hz, stereo, fltp, 96 kb/s (default)
    
    Metadata:
    
      creation_time   : 2019-07-31T14:43:18.000000Z
    
      handler_name    : Core Media Audio
    
      encoder         : Lavc58.35.100 aac
    
frame=13563 fps=0.0 q=-1.0 Lsize=   10903kB time=00:03:46.08 bitrate= 395.1kbits/s speed= 916x
    
video:10699kB audio:10kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 1.805767%

    How can I get around this limitation?

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