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• Proprietary codecs on Linux. What is legal ?

  17 octobre 2016, par George Eco

  So, assuming we got a distribution without proprietary codecs installed.
  Let’s take Linux Mint for example. I want to store and playback wav and ogg format sounds, either by using my own software, or by using another developer’s software. So far so good right ?

  Imagine now that we have the following scenario. For some reason, I wanna playback a file that is either an mp4 or mp3 or mpeg or any other format, made by proprietary codecs. Instantly, I will need a codec for these formats.

  I read somewhere that Fluendo sells solutions for "legal codec usage" for linux distros.
  URL of fluendo : http://www.fluendo.com/en/

  So here comes the questions :

  Using VLC and ffmpeg is enough for me to convert a file to an ogg or ogv so I can playback a song or a video using an open format. You can also playback playback files made by proprietary formats. But are VLC and ffmpeg legal to use, to playback such files made by proprietary codecs ? For example, ss VLC codecs okay to be used without paying anyone for mp4 playback ? Is it okay to convert a file from mp4 to ogv ?
  If not, are there any legal and open source and free (as in freedom) codecs around that can solve the issue, or does someone have to pay a product, to be ethically correct, to the developers of the proprietaty codecs ?

  Note that I do not ask for Windows, since codec licenses are included to the price of the operating system. I ask exclusively for a free linux distribution.

• Extract files from mpeg video

  28 octobre 2013, par A Dark Divided Gem

  Videos created with Camtasia can be shared on the web by exporting the project for the TechSmith Smart Player. The video is exported in the "H264 - MPEG-4 AVC (part10) (avc1)" codec and the export also includes other custom XML, JavaScript and SWF files used by the TechSmith Smart Player.

  These custom files are also "burnt" into the video itself. For example the contents of the XML file can be viewed when opening the MP4 video in a text editor. This allows other services to only ask for the MP4 file when uploading Camtasia videos.

  Therefore my question is how do you extract text and binary files from a MP4 video file ? For this project I am limited to Java but I am happy to call an external executable as well.

  I tried the "-dump_attachment" option in FFmpeg but that didn't work and I am out of ideas.

  C :\Users\Desktop>ffmpeg -dump_attachment:t "" -i getting-started-project.mp4
  ffmpeg version N-57448-gc78a416 Copyright (c) 2000-2013 the FFmpeg developers
    built on Oct 26 2013 18:08:54 with gcc 4.8.2 (GCC)
    configuration : —enable-gpl —enable-version3 —disable-w32threads —enable-av
  isynth —enable-bzlib —enable-fontconfig —enable-frei0r —enable-gnutls —enab
  le-iconv —enable-libass —enable-libbluray —enable-libcaca —enable-libfreetyp
  e —enable-libgsm —enable-libilbc —enable-libmodplug —enable-libmp3lame —ena
  ble-libopencore-amrnb —enable-libopencore-amrwb —enable-libopenjpeg —enable-l
  ibopus —enable-librtmp —enable-libschroedinger —enable-libsoxr —enable-libsp
  eex —enable-libtheora —enable-libtwolame —enable-libvidstab —enable-libvo-aa
  cenc —enable-libvo-amrwbenc —enable-libvorbis —enable-libvpx —enable-libwavp
  ack —enable-libx264 —enable-libxavs —enable-libxvid —enable-zlib
    libavutil      52. 47.101 / 52. 47.101
    libavcodec     55. 38.101 / 55. 38.101
    libavformat    55. 19.104 / 55. 19.104
    libavdevice    55.  5.100 / 55.  5.100
    libavfilter     3. 89.100 /  3. 89.100
    libswscale      2.  5.101 /  2.  5.101
    libswresample   0. 17.104 /  0. 17.104
    libpostproc    52.  3.100 / 52.  3.100
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'getting-started-project.mp4' :
    Metadata :
      major_brand : mp42
      minor_version : 0
      compatible_brands : isommp42
      creation_time : 2013-10-24 15:53:19
      artist :
      description :
      title : Untitled
    Duration : 00:05:41.12, start : 0.000000, bitrate : 314 kb/s
      Stream #0:0(eng) : Video : h264 (Baseline) (avc1 / 0x31637661), yuv420p(tv), 6
  40x360 [SAR 1:1 DAR 16:9], 185 kb/s, 30 fps, 30 tbr, 30k tbn, 60 tbc (default)
      Metadata :
        creation_time : 2013-10-24 15:53:19
        handler_name : Mainconcept MP4 Video Media Handler
      Stream #0:1(eng) : Audio : aac (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 12
  5 kb/s (default)
      Metadata :
        creation_time : 2013-10-24 15:53:19
        handler_name : Mainconcept MP4 Sound Media Handler
   At least one output file must be specified

  Update : It appears the XML is contained within a custom UUID atom and I just need a way of extracting that.

  Thanks

• ffmpeg change video stream resolution

  10 décembre 2014, par skorpionet

  I have an MKV with a video stream with wrong resolution of 1920x800, but the inside film is 1920x1080 so my main video player, an LG Smart TV, shows a flattened image. I can easily change resolution in container metadata but LG TV ignores this data and read only video stream data.

  First question : only way to change video stream resolution data is scale the video ?

  To scale with ffmpeg I used this command :

  ffmpeg -i input.mkv -map 0 -c:a copy -c:s copy -c:v libx264 -preset slow -crf 17 -vf scale=1920:1080,setdar=16/9 output.mkv

  Now the mkv is fine, my LG TV read it, looks awesome but..... size went from 3,3Gb to 12Gb !!
  Overall bit rate of 3,3Gb video is 2.704 Kbps, 12Gb is 9.829 Kbps. I think that 7000Kbps more are useless, in original video there aren’t info to raise quality.

  Second question : Why this huge size change ? What is my mistake ?

  Best Regards