Recherche avancée

Sur d’autres sites (11797)

• How to convert a Video to a Slideshow with synced audio ? [closed]

  25 mai 2013, par Henry Mazza

  I want a simple way to convert a Ted Talk Presentation to a SlideShow + (synced)Audio format so I can listen to it in my car. I don't want to lose most of the visuals as it does in the audio format and also want to reduce the storage/cell data needs of the video format.

  So far I already extracted the key scenes with timing and the audio, now I must glue this together in a synced fashion.

  Possible ways I found but couldn't make work :

  • MP4Box to make a .m4b (audiobook/enhanced podcast) with mp4chap to set each image as a chapter image (but I could find proper documentation on how to do this)
  • FFMPEG to make a flat movie with the images (but I couldn't make each image stay for a random period of time)

  Ultimately I will automate this process in my VPS and make my private podcast server, so no fancy tools that don't work in Linux, please.

  EDIT : actually the Podcast is a lousy idea, the artwork must be in a square aspect ratio and has great compatibility problems with varius players. Still studing the Book format.

• Revision 34710 : Amélioration de la fonction d’installation ... très chouette en SPIP 2.1 ...

  24 janvier 2010, par kent1@… — Log

  Amélioration de la fonction d’installation ... très chouette en SPIP 2.1 (bis ...)

• How can I concat several videos generated by MediaRecorder slices

  28 mai 2023, par Bruno Francisco

  I have the following frontend code :

  


  const mediaRecorder = new MediaRecorder(stream, {
        mimeType: 'video/webm'
    });

    mediaRecorder.start(10000);

    mediaRecorder.ondataavailable = (e) => {
        const formData = new FormData();

        formData.append('video', new Blob([e.data], { 'type' : 'video/webm;' }));

        fetch('http://localhost/api/session/12/video/stream', {
            method: 'POST',
            body: formData,
        }).then(() => {
            console.log('success')
        }).catch((e) => {
            console.log('error')
            console.log(e);
        });
    };


  


  Then, in the backend I'm saving the each 10 seconds video into a folder. Then, whenever the user finishes his session, we would like to stitch together all the videos together.

  


  If the user has recorded for 20 seconds, we will have 2 videos of 10 seconds.

  


  I have the following files in my folder :

  


  erKa3MVTuDfnuDUQUhUd2huUaCKfihtm8thc0KX0.bin
hAhJfVNxMEJK2MsyR99a7t7UkT3pjHkmdN1j2C9G.mkv


  


  I'm assuming that the first slice generated by MediaRecord includes the mime type, while the subsequent parts do not have mime types, generating a .bin file.

  


  Now, I run the following command to stitch all parts together :

  


  ffmpeg -i erKa3MVTuDfnuDUQUhUd2huUaCKfihtm8thc0KX0.bin -i hAhJfVNxMEJK2MsyR99a7t7UkT3pjHkmdN1j2C9G.mkv -filter_complex "concat=n=2:v=0:a=1" -vn -y final-video.mp4


  


  Then I get the following error :

  


  ffmpeg version 4.4.2-0ubuntu0.22.04.1 Copyright (c) 2000-2021 the FFmpeg developers
  built with gcc 11 (Ubuntu 11.2.0-19ubuntu1)
  configuration: --prefix=/usr --extra-version=0ubuntu0.22.04.1 --toolchain=hardened --libdir=/usr/lib/aarch64-linux-gnu --incdir=/usr/include/aarch64-linux-gnu --arch=arm64 --enable-gpl --disable-stripping --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libdav1d --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librabbitmq --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzimg --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-pocketsphinx --enable-librsvg --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared
  libavutil      56. 70.100 / 56. 70.100
  libavcodec     58.134.100 / 58.134.100
  libavformat    58. 76.100 / 58. 76.100
  libavdevice    58. 13.100 / 58. 13.100
  libavfilter     7.110.100 /  7.110.100
  libswscale      5.  9.100 /  5.  9.100
  libswresample   3.  9.100 /  3.  9.100
  libpostproc    55.  9.100 / 55.  9.100
[h264 @ 0xaaaaf1ad3a70] non-existing PPS 0 referenced
    Last message repeated 1 times

...

Input #0, h264, from 'erKa3MVTuDfnuDUQUhUd2huUaCKfihtm8thc0KX0.bin':
  Duration: N/A, bitrate: N/A
  Stream #0:0: Video: h264 (Baseline), yuv420p(tv, bt709, progressive), 1920x1080, 25 fps, 25 tbr, 1200k tbn, 50 tbc
Input #1, matroska,webm, from 'hAhJfVNxMEJK2MsyR99a7t7UkT3pjHkmdN1j2C9G.mkv':
  Metadata:
    encoder         : Chrome
  Duration: N/A, start: 0.000000, bitrate: N/A
  Stream #1:0(eng): Video: h264 (Baseline), yuv420p(tv, bt709, progressive), 1920x1080, SAR 1:1 DAR 16:9, 29.33 fps, 29.33 tbr, 1k tbn, 2k tbc (default)
Cannot find a matching stream for unlabeled input pad 0 on filter Parsed_concat_0


  


  Is there any way to stitch all files together ? Do I have to send the mime type on each time ondataavailable is called ?