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Autres articles (62)

  • Les autorisations surchargées par les plugins

    27 avril 2010, par

    Mediaspip core
    autoriser_auteur_modifier() afin que les visiteurs soient capables de modifier leurs informations sur la page d’auteurs

  • Publier sur MédiaSpip

    13 juin 2013

    Puis-je poster des contenus à partir d’une tablette Ipad ?
    Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir

  • Les formats acceptés

    28 janvier 2010, par

    Les commandes suivantes permettent d’avoir des informations sur les formats et codecs gérés par l’installation local de ffmpeg :
    ffmpeg -codecs ffmpeg -formats
    Les format videos acceptés en entrée
    Cette liste est non exhaustive, elle met en exergue les principaux formats utilisés : h264 : H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 m4v : raw MPEG-4 video format flv : Flash Video (FLV) / Sorenson Spark / Sorenson H.263 Theora wmv :
    Les formats vidéos de sortie possibles
    Dans un premier temps on (...)

Sur d’autres sites (7821)

  • ffmpeg Error : Pattern type 'glob' was selected but globbing is not support ed by this libavformat build

    14 septembre 2017, par Aryan Naim

    I’m trying to convert group of ".jpg" files acting as individual frames into 1 single mpeg video ".mp4"

    Example parameters i used :

    frame duration  = 2 secs
    frame rate      = 30  fps
    encoder         = libx264 (mpeg)
    input pattern   = "*.jpg"
    output pattern  = video.mp4

    Based on ffmpeg wiki instructions at (https://trac.ffmpeg.org/wiki/Create%20a%20video%20slideshow%20from%20images), I issued this command :

    ffmpeg -framerate 1/2 -pattern_type glob -i "*.jpg" -c:v libx264 -r 30 -pix_fmt yuv420p video.mp4

    But I’m getting this error :

    [image2 @ 049ab120] Pattern type 'glob' was selected but globbing is not
    supported by this libavformat build *.jpg: Function not implemented

    Which probably means the API pattern matching commands for my build/version have changed. By the way this my windows 32bit ffmpeg download build (ffmpeg-20150702-git-03b2b40-win32-static).

    How can I choose a group of files using pattern matching using ffmpeg ?

  • displaying a baseline h264 frames stream in browsers

    6 août 2021, par Thabet Sabha

    So, I have a server that receives a live rtsp stream then generates baseline h264 frames using ffmpeg, which then are sent via an rtcDataChannel to browser, and while the frames arrive as intended, I can't figure out a way to display them on my html5 videoElement,
here is a simplified version of my current approach :

    


    const remoteStream = new MediaSource();&#xA;myVideoElement.src = window.URL.createObjectURL(remoteStream);&#xA;&#xA;// called when remoteStream.readyState === "open"&#xA;let sourceBuffer = remoteStream.addSourceBuffer(&#x27;video/mp4; codecs="avc1.4d002a"&#x27;);&#xA;&#xA;// this gets called when ever a new frame is received from the webrtc data channel.&#xA;function onFrame(frame) {&#xA;      sourceBuffer.appendBuffer(new Uint8Array(frame));&#xA;&#xA;      /*&#xA;      console.log(frame) ==> <buffer 00="00" 01="01" 41="41" 9b="9b" a0="a0" 22="22" 80="80" a5="a5" d7="d7" 42="42" ea="ea" 34="34" 14="14" 85="85" ba="ba" bc="bc" 1b="1b" f2="f2" 71="71" 0d="0d" 8b="8b" e1="e1" 3c="3c" 52="52" d5="d5" 8c="8c" ef="ef" c1="c1" 89="89" 10="10" c5="c5" 05="05" 78="78" ee="ee" 1d="1d" 03="03" 8d="8d" 2896="2896" more="more" bytes="bytes">&#xA;      */&#xA;}&#xA;</buffer>

    &#xA;

    ffmpeg options :

    &#xA;

    [&#xA;    "-rtsp_transport", "tcp",&#xA;    "-i", `${rtspCamURL}`,  &#xA;    "-framerate", "15",&#xA;    "-c:v", "libx264",&#xA;    "-vprofile", "baseline",&#xA;    "-b:v", "600k",&#xA;    "-bufsize", "600k",&#xA;    "-pix_fmt", "yuv420p",&#xA;    &#x27;-tune&#x27;, &#x27;zerolatency&#x27;,&#xA;    "-preset", "ultrafast",&#xA;    "-f", "rawvideo",&#xA;    &#x27;-&#x27;&#xA;]; &#xA;

    &#xA;

    ffmpeg stream is then split using NAL delimiter (to generate individual frames) then each frame is sent via the data channel like so :&#xA;Buffer.concat([nalDelimiter, frame]).

    &#xA;

    I am not sure if i'm missing something as i'm not getting any helpful errors due to the remoteSource closing as soon as the first frame arrives for some reason.

    &#xA;

    or does the media source just not support raw h264 frames, and if so is there a workaround to solve this issue ? (even if it has to do with changing the ffmpeg params.

    &#xA;

  • ffmpeg concat drops audio frames

    5 octobre 2017, par Shaun

    I have an mp4 file and I want to take two sequential sections of the video out and render them as individual files, later recombining them back into the original video. For instance, with my video video.mp4, I can run

    ffmpeg -i video.mp4 -ss 56 -t 4 out1.mp4
    ffmpeg -i video.mp4 -ss 60 -t 4 out2.mp4

    creating out1.mp4 which contains 00:00:56 to 00:01:00 of video.mp4, and out2.mp4 which contains 00:01:00 to 00:01:04. However, later I want to be able to recombine them again quickly (i.e., without reencoding), so I use the concat demuxer,

    ffmpeg -f concat -safe 0 -i files.txt -c copy concat.mp4

    where files.txt contains

    file out1.mp4
    file out2.mp4

    which theoretically should give me back 00:00:56 to 00:01:04 of video.mp4, however there are always dropped audio frames where the concatenation occurs, creating a very unpleasant sound artifact, an audio blip, if you will.

    missing audio frames

    I have tried using async and -af apad on initially creating the two sections of the video but I am still faced with the same problem, and have not found the solution elsewhere. I have experienced this issue in multiple different use cases, so hopefully this simple example will shed some light on the real problem.