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• Revision b98a1a43ce41afe3be303d168e308dacbb8d2d30 : Mais non, là on est revenu à la case départ. La confusion c’était entre ...

  15 septembre 2010, par Committo,Ergo:sum — Log

  Mais non, là on est revenu à la case départ. La confusion c’était entre true et continue de l’argument option de sql_getfetsel. Ce coup-ci on a bien à la fois le logout correct, le login automatique à l’install, et l’install forcée en cas de fichier corrompu. git-svn-id : (...)

• Transcoding & displaying user-uploaded videos for cross-browser/platform compatibility

  5 avril 2012, par Jonathan Amend

  I want to display user-uploaded videos in high quality on different browsers/platforms. I think I have a pretty good start, but there are a few issues. I have at my disposal ffmpeg 0.10 (called from PHP) and jwPlayer 5.8 (licensed).

  Ideally I would like to support :

  • Browsers with Flash 9+
  • Modern Firefox/Chrome/Safari without Flash
  • iOS 4.1+
  • Android 2.2+

  My current transcoding commands are :

  $commands = array(
  
      'flv' => "/usr/bin/ffmpeg -y -i {$sourceFile} -b 500k -ar 22050 -ab 64 {$tmpFileName}.flv 2>&1",
  
      'webm' => "/usr/bin/ffmpeg -i {$sourceFile} -acodec libvorbis -ac 2 -ab 96k -ar 44100 -b 500k {$tmpFileName}.webm 2>&1",
  
      'mp4' => "/usr/bin/ffmpeg -i {$sourceFile} -acodec libfaac -ab 96k -vcodec libx264 -level 21 -refs 2 -vf 'scale=trunc(ih*a/2)*2:trunc(iw/a/2)*2' -b 500k -bt 1000k -threads 0 -f mp4 {$tmpFileName}.pre.mp4 2>&1",
  
      'jpg' => "/usr/bin/ffmpeg -y -i {$sourceFile} -ss 5 -vcodec mjpeg -vframes 1 -an -f rawvideo {$tmpFileName}.jpg 2>&1"
  
  );
  
  
  
  $fastStartCommand = "/usr/bin/qt-faststart {$tmpFileName}.pre.mp4 {$tmpFileName}.mp4");

  My current display code is this :

  <video controls="controls" width="{$width}" height="{$height}" poster="{$fileJPG}" style="width: {$width}px; height: {$height}px;">
  
      <source src="{$fileMP4}" type="video/mp4" data-ext="mp4"></source>
  
      <source src="{$fileWEBM}" type="video/webm" data-ext="webm"></source>
  
      <a href="http://stackoverflow.com/feeds/tag/{$fileMP4}" title="Play Video">
  
          <img border="0" src="http://stackoverflow.com/feeds/tag/{$fileJPG}" width='0' height='0' alt="Play Video" />
  
      </a>
  
  </video>
  
  <code class="echappe-js">&lt;script type=&quot;text/javascript&quot;&gt;<br />
  
  swfobject.embedSWF(<br />
  
      &amp;#39;/flash/jwPlayer.swf&amp;#39;,<br />
  
      &amp;#39;video&amp;#39;,<br />
  
      {$width},<br />
  
      {$height},<br />
  
      &amp;#39;9.0.0&amp;#39;,<br />
  
      &amp;#39;&amp;#39;,<br />
  
      {<br />
  
          file: &amp;#39;{$fileFLV}&amp;#39;,<br />
  
          width: {$width},<br />
  
          height: {$height},<br />
  
          provider: &amp;#39;video&amp;#39;,<br />
  
          stretching: &amp;#39;uniform&amp;#39;,<br />
  
          smoothing: &amp;#39;true&amp;#39;,<br />
  
          dock: &amp;#39;true&amp;#39;<br />
  
      },<br />
  
      {<br />
  
          menu: &amp;#39;false&amp;#39;,<br />
  
          allowfullscreen: &amp;#39;true&amp;#39;,<br />
  
          allowscriptaccess: &amp;#39;always&amp;#39;,<br />
  
          allownetworking: &amp;#39;always&amp;#39;,<br />
  
          wmode: &amp;#39;transparent&amp;#39;<br />
  
      }<br />
  
  );<br />
  
  &lt;/script&gt;
  
  

  The idea is to prefer the Flash player (we have many custom skins that we would like to keep using), then fall back to HTML 5 video, and if that fails, show the JPEG with a link to the mp4 file (that seems to work as a last-ditch effort for iOS 2/3 and old browsers so they can at least play the video by launching QuickTime).

  The main issues that I'm not sure how to solve right now are :

  • How can I show a higher quality video in Flash ? I tried using the mp4 video instead of the flv but it doesn't work and I only get sound, no video. I think Flash is supposed to support h.264 these days, but how ? And do I have to use a different transcoding method for older and newer versions of Flash ?
  • How can I transcode the video with better quality ? Right now I am using the same bitrate for all resolutions. Any chance there is a way for ffmpeg to adjust the bitrate automatically ? Or can I detect and match the resolution of the uploaded video to a list of resolution -> bitrates somehow ?

• Changing int main() to JNI interface prototype

  13 mars 2012, par iSun

  I changed ffmpeg.c according following link :

  http://www.roman10.net/how-to-port-ffmpeg-the-program-to-androidideas-and-thoughts/

  He said the change main () to JNI interface prototype. Well, I'm not familiar with JNI interface prototype, but I read an article about JNI and change it accordingly.

  Can anyone look at my code to see is this true or not ?

  JNIEXPORT jint JNICALL Java_com_ffmpegtest_MainActivity_main(JNIEnv *pEnv, int argc, char **argv) {
  
  int64_t ti;
  
  
  
  av_log_set_flags(AV_LOG_SKIP_REPEATED);
  
  
  
  if(argc>1 && !strcmp(argv[1], "-d")){
  
  run_as_daemon=1;
  
  verbose=-1;
  
  av_log_set_callback(log_callback_null);
  
  argc--;
  
  argv++;
  
  
  
  }
  
  
  
  avcodec_register_all();
  
  #if CONFIG_AVDEVICE
  
  avdevice_register_all();
  
  #endif
  
  #if CONFIG_AVFILTER
  
  avfilter_register_all();
  
  #endif
  
  av_register_all();
  
  
  
  #if HAVE_ISATTY
  
  if(isatty(STDIN_FILENO))
  
  avio_set_interrupt_cb(decode_interrupt_cb);
  
  #endif
  
  
  
  init_opts();
  
  
  
  if(verbose>=0)
  
  show_banner();
  
  
  
  /* parse options */
  
  parse_options(argc, argv, options, opt_output_file);
  
  
  
  if(nb_output_files <= 0 && nb_input_files == 0) {
  
  show_usage();
  
  fprintf(stderr, "Use -h to get full help or, even better, run 'man ffmpeg'\n");
  
  ffmpeg_exit(1);
  
  }
  
  
  
  /* file converter / grab */
  
  if (nb_output_files <= 0) {
  
  fprintf(stderr, "At least one output file must be specified\n");
  
  ffmpeg_exit(1);
  
  }
  
  
  
  if (nb_input_files == 0) {
  
  fprintf(stderr, "At least one input file must be specified\n");
  
  ffmpeg_exit(1);
  
  }
  
  
  
  ti = getutime();
  
  if (transcode(output_files, nb_output_files, input_files, nb_input_files,
  
  stream_maps, nb_stream_maps) < 0)
  
  ffmpeg_exit(1);
  
  ti = getutime() - ti;
  
  if (do_benchmark) {
  
  int maxrss = getmaxrss() / 1024;
  
  printf("bench: utime=%0.3fs maxrss=%ikB\n", ti / 1000000.0, maxrss);
  
  }
  
  
  
  return ffmpeg_exit(0);
  
  }