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  • Supporting all media types

    13 avril 2011, par

    Unlike most software and media-sharing platforms, MediaSPIP aims to manage as many different media types as possible. The following are just a few examples from an ever-expanding list of supported formats : images : png, gif, jpg, bmp and more audio : MP3, Ogg, Wav and more video : AVI, MP4, OGV, mpg, mov, wmv and more text, code and other data : OpenOffice, Microsoft Office (Word, PowerPoint, Excel), web (html, CSS), LaTeX, Google Earth and (...)

  • Selection of projects using MediaSPIP

    2 mai 2011, par

    The examples below are representative elements of MediaSPIP specific uses for specific projects.
    MediaSPIP farm @ Infini
    The non profit organizationInfini develops hospitality activities, internet access point, training, realizing innovative projects in the field of information and communication technologies and Communication, and hosting of websites. It plays a unique and prominent role in the Brest (France) area, at the national level, among the half-dozen such association. Its members (...)

  • Les vidéos

    21 avril 2011, par

    Comme les documents de type "audio", Mediaspip affiche dans la mesure du possible les vidéos grâce à la balise html5 .
    Un des inconvénients de cette balise est qu’elle n’est pas reconnue correctement par certains navigateurs (Internet Explorer pour ne pas le nommer) et que chaque navigateur ne gère en natif que certains formats de vidéos.
    Son avantage principal quant à lui est de bénéficier de la prise en charge native de vidéos dans les navigateur et donc de se passer de l’utilisation de Flash et (...)

Sur d’autres sites (3367)

  • FFmpeg - selecting appropriate bitrate for VP9 encoding

    11 janvier 2018, par fastily

    I am looking to encode a 4k video shot with iPhone 6s in VP9 in the best quality possible.

    For reference, stream data of the video I would like to encode, via ffprobe :

    Duration: 00:00:10.48, start: 0.000000, bitrate: 46047 kb/s
    
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv, bt709), 3840x2160, 45959 kb/s, 29.98 fps, 29.97 tbr, 600 tbn, 1200 tbc (default)
    
    Metadata:
    
      creation_time   : 2017-03-13T21:12:56.000000Z
    
      handler_name    : Core Media Data Handler
    
      encoder         : H.264
    
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, mono, fltp, 79 kb/s (default)
    
    Metadata:
    
      creation_time   : 2017-03-13T21:12:56.000000Z
    
      handler_name    : Core Media Data Handler

    I am using the following FFmpeg commands, based on these instructions (see Best Quality (Slowest) Recommended Settings section).

    1. ffmpeg -i INPUT.mov -c:v libvpx-vp9 -pass 1 -b:v 46000K -threads 4 -speed 4 -g 9999 -an -f webm -y /dev/null
    2. ffmpeg -I INPUT.mov -c:v libvpx-vp9 -pass 2 -b:v 46000K -threads 4 -speed 0 -g 9999 -an -f webm OUTPUT.webm

    Is there a best practice to select an optimal -b:v value such that the resulting video is visually indistinguishable from the original ? I have tried values ranging from 36000K-46000K, but these result in massive files with an overall bitrate exceeding the target bitrate.

    Thanks in advance !

  • FFmpeg - selecting appropriate bitrate for VP9 encoding

    6 avril 2017, par fastily

    I am looking to encode a 4k video shot with iPhone 6s in VP9 in the best quality possible.

    For reference, stream data of the video I would like to encode, via ffprobe :

    Duration: 00:00:10.48, start: 0.000000, bitrate: 46047 kb/s
    
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv, bt709), 3840x2160, 45959 kb/s, 29.98 fps, 29.97 tbr, 600 tbn, 1200 tbc (default)
    
    Metadata:
    
      creation_time   : 2017-03-13T21:12:56.000000Z
    
      handler_name    : Core Media Data Handler
    
      encoder         : H.264
    
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, mono, fltp, 79 kb/s (default)
    
    Metadata:
    
      creation_time   : 2017-03-13T21:12:56.000000Z
    
      handler_name    : Core Media Data Handler

    I am using the following FFmpeg commands, based on these instructions (see Best Quality (Slowest) Recommended Settings section).

    1. ffmpeg -i INPUT.mov -c:v libvpx-vp9 -pass 1 -b:v 46000K -threads 4 -speed 4 -g 9999 -an -f webm -y /dev/null
    2. ffmpeg -I INPUT.mov -c:v libvpx-vp9 -pass 2 -b:v 46000K -threads 4 -speed 0 -g 9999 -an -f webm OUTPUT.webm

    Is there a best practice to select an optimal -b:v value such that the resulting video is visually indistinguishable from the original ? I have tried values ranging from 36000K-46000K, but these result in massive files with an overall bitrate exceeding the target bitrate.

    Thanks in advance !

  • Converting HLS video with fmp4 segments to image thumbnails via ffmpeg with start offset using fast seek

    19 octobre 2022, par hellerahum

    I'm having trouble with what I think should be a basic use case for ffmpeg. What I'd like to do is take an hls video in fmp4 and output 30s of images at 10fps, using "fast seek" to start at an offset well into the video. This works with an Apple sample using ts segments, but not with fmp4 segments.

    


    working sample (ts)

    


    ffmpeg -ss 00:00:05 -i https://devimages.apple.com.edgekey.net/iphone/samples/bipbop/bipbopall.m3u8 -t 30 -vf fps=10 hls_samples/img%03d.jpg


    


    broken sample (fmp4)

    


    ffmpeg -ss 00:00:05 -i https://devstreaming-cdn.apple.com/videos/streaming/examples/img_bipbop_adv_example_fmp4/master.m3u8 -t 30 -vf fps=10 hls_samples/img%03d.jpg


    


    The broken sample spits out errors like :

    


    [NULL @ 0x123e30d20] Invalid NAL unit size (-2003396084 > 1673).
[NULL @ 0x123e30d20] missing picture in access unit with size 1677


    


    and then finally :

    


    Output file is empty, nothing was encoded (check -ss / -t / -frames parameters if used)
Conversion failed!


    


    When I re-encode the fmp4 video adding keyframes via -g 1 (still hls with fmp4) I'm then able to use the fast seek -ss flag before the -i , but i'd rather not do this in a 2-step process, and ideally would take the original hls/fmp4 manifest and output the thumbnails directly. Both samples work with the -ss flag after the input (slow seek) but I have some long (10+ hour) videos so that's not tenable. Anyone able to point me to what I'm doing wrong, or is it possible this is an issue with ffmpeg and its support for fmp4 ? I'm using ffmpeg v5.1.2 and have checked on both an M1 mac and Ubuntu system.

    


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