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• Easy Tricks for Finding WebM Videos in YouTube

  9 août 2010, par noreply@blogger.com (John Luther)

  Since the WebM project launch, YouTube has been encoding videos uploaded at 720p or higher resolution in the WebM format. Today, the one million most popular videos of any size on YouTube are also available in the WebM format.

  We have instructions on our project site for finding these videos but they require adding a special parameter onto the end of each search query. All of the browsers that support WebM can create search shortcuts with custom parameters, however, so we’ve compiled instructions for making it very simple to search for WebM videos in YouTube.

  Important : First, make sure you have a supported browser and are enrolled in the YouTube HTML5 beta by going to http://youtube.com/html5 and clicking Enter the HTML5 Beta.

  Creating a WebM Search Shortcut

  Firefox 4 Beta :
  

  1. Select Bookmarks > Organize Bookmarks. A bookmark manager dialog opens.
  2. In the left column, choose a location for the new bookmark you’re creating. Next, choose Organize > New Bookmark (on MacOS click the gear icon). The new bookmark dialog opens.
  3. In the Name box, type WebM.
  4. In the Location box, type http://youtube.com/results?search_query=%s&webm=1.
  5. In the Keyword box, type webm.
  6. Click Add.

  Google Chrome Early Release Channel :
  

  1. On Windows and Linux, click the Chrome wrench icon in the toolbar and select Options. On MacOS, select Chrome > Preferences.
  2. On the Basics tab, click the Manage button in the Default Search section.
  3. On Windows and Linux, click Add. On MacOS X, click the plus (+) button.
  4. In the Name box, type WebM.
  5. In the Keyword box, type webm.
  6. In the URL box, type http://youtube.com/results?search_query=%s&webm=1.
  7. Click OK.

  Opera 10.60 and later :
  

  1. Go to http://youtube.com.
  2. Right-click in the YouTube search box at the top of the page and select Create Search. On MacOS, use Ctrl+click if you don’t a secondary mouse button enabled.
  3. In the Name box, type WebM.
  4. In the Keyword box, type webm.
  5. In the Address box, type http://youtube.com/results?search_query=%s&webm=1.
  6. Click OK.

  
  

  
  Now you’re ready to search. In the location box of the browser, type webm monster trucks. The YouTube search results page will open with a selection of monster truck videos encoded in the WebM format. When watching a video, look for the HTML5 WebM indicator in the player control bar.

  If you can’t find WebM videos it is most likely a browser cookie problem. Your enrollment in the YouTube HTML5 beta test is stored in a browser cookie (not in your YouTube or Google account), and that cookie can expire. Visit http://youtube.com/html5 and opt-in again to re-set the cookie.

  Directly Accessing WebM Videos by URL

  To find out if any YouTube video is available in WebM, simply add &html5=True (make sure True is capitalized) to the end of the video URL. If there is a WebM version of the video, it will open instead of the Flash version. For example :
  

  • Flash version : http://www.youtube.com/watch?v=Dz6gFokvOr0
  • WebM version : http://www.youtube.com/watch?v=Dz6gFokvOr0&html5=True

  

• Easy Tricks for Finding WebM Videos in YouTube

  9 août 2010, par noreply@blogger.com (John Luther)

  Since the WebM project launch, YouTube has been encoding videos uploaded at 720p or higher resolution in the WebM format. Today, the one million most popular videos of any size on YouTube are also available in the WebM format.

  We have instructions on our project site for finding these videos but they require adding a special parameter onto the end of each search query. All of the browsers that support WebM can create search shortcuts with custom parameters, however, so we’ve compiled instructions for making it very simple to search for WebM videos in YouTube.

  Important : First, make sure you have a supported browser and are enrolled in the YouTube HTML5 beta by going to http://youtube.com/html5 and clicking Enter the HTML5 Beta.

  Creating a WebM Search Shortcut

  Firefox 4 Beta :
  

  1. Select Bookmarks > Organize Bookmarks. A bookmark manager dialog opens.
  2. In the left column, choose a location for the new bookmark you’re creating. Next, choose Organize > New Bookmark (on MacOS click the gear icon). The new bookmark dialog opens.
  3. In the Name box, type WebM.
  4. In the Location box, type http://youtube.com/results?search_query=%s&webm=1.
  5. In the Keyword box, type webm.
  6. Click Add.

  Google Chrome Early Release Channel :
  

  1. On Windows and Linux, click the Chrome wrench icon in the toolbar and select Options. On MacOS, select Chrome > Preferences.
  2. On the Basics tab, click the Manage button in the Default Search section.
  3. On Windows and Linux, click Add. On MacOS X, click the plus (+) button.
  4. In the Name box, type WebM.
  5. In the Keyword box, type webm.
  6. In the URL box, type http://youtube.com/results?search_query=%s&webm=1.
  7. Click OK.

  Opera 10.60 and later :
  

  1. Go to http://youtube.com.
  2. Right-click in the YouTube search box at the top of the page and select Create Search. On MacOS, use Ctrl+click if you don’t a secondary mouse button enabled.
  3. In the Name box, type WebM.
  4. In the Keyword box, type webm.
  5. In the Address box, type http://youtube.com/results?search_query=%s&webm=1.
  6. Click OK.

  
  

  
  Now you’re ready to search. In the location box of the browser, type webm monster trucks. The YouTube search results page will open with a selection of monster truck videos encoded in the WebM format. When watching a video, look for the HTML5 WebM indicator in the player control bar.

  If you can’t find WebM videos it is most likely a browser cookie problem. Your enrollment in the YouTube HTML5 beta test is stored in a browser cookie (not in your YouTube or Google account), and that cookie can expire. Visit http://youtube.com/html5 and opt-in again to re-set the cookie.

  Directly Accessing WebM Videos by URL

  To find out if any YouTube video is available in WebM, simply add &html5=True (make sure True is capitalized) to the end of the video URL. If there is a WebM version of the video, it will open instead of the Flash version. For example :
  

  • Flash version : http://www.youtube.com/watch?v=Dz6gFokvOr0
  • WebM version : http://www.youtube.com/watch?v=Dz6gFokvOr0&html5=True

  

• ffmpeg adding 6 secs of black frames in the beginning of a file

  7 août 2014, par user3842039

  Trying to convert a .mov file (h264 and pcm) generated in Mpegstreamclip (MacOS) and the result is strangely out of sync with around 6 seconds of black frames at the beginning. I have tried many differente audio and video codec and the result is the same even with a -vcodec copy and -acodec copy. Below the return of ffmpeg (git version compiled today - 06/08/2014) :

          ffmpeg -i /media/dados/x/PGM-970.mov -vcodec copy -acodec copy  /media/dados/convertidos/PGM-970-converted-ffmpeg-compilado.mov 
  
      ffmpeg version 2.3.git-1ace957 Copyright (c) 2000-2014 the FFmpeg developers
  
        built on Jul 26 2014 20:25:06 with gcc 4.8 (Ubuntu 4.8.2-19ubuntu1)
  
        configuration: --extra-libs=-ldl --prefix=/opt/ffmpeg --enable-avresample --disable-debug --enable-nonfree --enable-gpl --enable-version3 --enable-x11grab --enable-libpulse --enable-libopencore-amrnb --enable-libopencore-amrwb --disable-decoder=amrnb --disable-decoder=amrwb --enable-libx264 --enable-libx265 --enable-libfdk-aac --enable-libvorbis --enable-libmp3lame --enable-libopus --enable-libvpx --enable-libspeex --enable-libass --enable-avisynth --enable-libsoxr
  
        libavutil      52. 92.101 / 52. 92.101
  
        libavcodec     55. 69.100 / 55. 69.100
  
        libavformat    55. 49.100 / 55. 49.100
  
        libavdevice    55. 13.102 / 55. 13.102
  
        libavfilter     4. 11.102 /  4. 11.102
  
        libavresample   1.  3.  0 /  1.  3.  0
  
        libswscale      2.  6.100 /  2.  6.100
  
        libswresample   0. 19.100 /  0. 19.100
  
        libpostproc    52.  3.100 / 52.  3.100
  
      [mov,mp4,m4a,3gp,3g2,mj2 @ 0x2ddac20] multiple edit list entries, a/v desync might occur, patch welcome
  
      [mov,mp4,m4a,3gp,3g2,mj2 @ 0x2ddac20] Concatenated H.264 or H.265 might not play correctly.
  
      Guessed Channel Layout for  Input Stream #0.1 : mono
  
      Guessed Channel Layout for  Input Stream #0.2 : mono
  
      Guessed Channel Layout for  Input Stream #0.3 : mono
  
      Guessed Channel Layout for  Input Stream #0.4 : mono
  
      Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/media/dados/x/PGM-970.mov':
  
        Metadata:
  
          major_brand     : qt  
  
          minor_version   : 537199360
  
          compatible_brands: qt  
  
          creation_time   : 2014-08-01 16:50:24
  
        Duration: 00:24:56.30, start: 0.000000, bitrate: 8350 kb/s
  
          Stream #0:0(eng): Video: h264 (Constrained Baseline) (avc1 / 0x31637661), yuv420p(tv, smpte1File '/media/dados/convertidos/PGM-970-converted-ffmpeg-compilado.mov' already exists. Overwrite ? [y/N] y
  
  
  
  70m), 720x480, 5258 kb/s, 29.97 fps, 29.97 tbr, 2997 tbn, 5994 tbc (default)
  
      Metadata:
  
        creation_time   : 2014-08-01 16:50:24
  
        handler_name    : Apple Alias Data Handler
  
        encoder         : H.264
  
        timecode        : 01:00:00;00
  
      Stream #0:1(eng): Audio: pcm_s16le (sowt / 0x74776F73), 48000 Hz, 1 channels, s16, 768 kb/s (default)
  
      Metadata:
  
        creation_time   : 2014-08-01 16:50:24
  
        File '/media/dados/convertidos/PGM-970-converted-ffmpeg-compilado.mov' already exists. Overwrite ? [y/N] yhandler_name    : Apple Alias Data Handler
  
      Stream #0:2(eng): Audio: pcm_s16le (sowt / 0x74776F73), 48000 Hz, 1 channels, s16, 768 kb/s (default)
  
      Metadata:
  
        creation_time   : 2014-08-01 16:50:24
  
        handler_name    : Apple Alias Data Handler
  
      Stream #0:3(eng): Audio: pcm_s16le (sowt / 0x74776F73), 48000 Hz, 1 channels, s16, 768 kb/s (default)
  
      Metadata:
  
        creation_time   : 2014-08-01 16:50:24
  
        handler_name    : Apple Alias Data Handler
  
      Stream #0:4(eng): Audio: pcm_s16le (sowt / 0x74776F73), 48000 Hz, 1 channels, s16, 768 kb/s (default)
  
      Metadata:
  
        creation_time   : 2014-08-01 16:50:24
  
        handler_name    : Apple Alias Data Handler
  
      Stream #0:5(eng): Data: none (tmcd / 0x64636D74) (default)
  
      Metadata:
  
        creation_time   : 2014-08-01 16:51:16
  
        handler_name    : Apple Alias Data Handler
  
        timecode        : 01:00:00;00
  
  
  
  Output #0, mov, to '/media/dados/convertidos/PGM-970-converted-ffmpeg-compilado.mov':
  
    Metadata:
  
      major_brand     : qt  
  
      minor_version   : 537199360
  
      compatible_brands: qt  
  
      encoder         : Lavf55.49.100
  
      Stream #0:0(eng): Video: h264 (avc1 / 0x31637661), yuv420p, 720x480, q=2-31, 5258 kb/s, 29.97 fps, 11988 tbn, 2997 tbc (default)
  
      Metadata:
  
        creation_time   : 2014-08-01 16:50:24
  
        handler_name    : Apple Alias Data Handler
  
        encoder         : H.264
  
        timecode        : 01:00:00;00
  
      Stream #0:1(eng): Audio: pcm_s16le (sowt / 0x74776F73), 48000 Hz, mono, 768 kb/s (default)
  
      Metadata:
  
        creation_time   : 2014-08-01 16:50:24
  
        handler_name    : Apple Alias Data Handler
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (copy)
  
    Stream #0:1 -> #0:1 (copy)
  
  Press [q] to stop, [?] for help

  Even ignoring the audio stream with "-an" ffmpeg persists to add the frames and alter the output duration.

  Any help is very much appreciated ! thanks in advance