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• How do I configure ffmpeg & openh264 so that the video file can be opened in Windows Media Player 12

  10 mars 2017, par Sacha Guyer

  I have successfully created h264/mp4 movie files with ffmpeg and the x264 library.

  Now I would like to change the h264 library from x264 to openH264. I could replace the x264 library with openH264, recompile ffmpeg and produce movie files, without changing my sources that produce the movie. The resulting movie opens fine in Quicktime on Mac, but on Windows, Windows Media Player 12 cannot play it.

  The documentation about Windows Media Player support for h264 is unclear. File types supported by Windows Media Player states in the table that Windows Media Player 12 supports mp4, but the text below says :

  Windows Media Player does not support the playback of the .mp4 file format.

  From what I have observed, Windows Media Player 12 IS capable of playing h264/mp4 files, but only when created with x264.

  Does anyone know how I need to adjust the configuration of the codec/context so that the movie plays in Windows Media Player ? Does Windows Media Player only support certain h264 profiles ?

  I noticed the warning :

  [libopenh264 @ 0x...] [OpenH264] this = 0x..., Warning:bEnableFrameSkip = 0,bitrate can’t be controlled for RC_QUALITY_MODE,RC_BITRATE_MODE and RC_TIMESTAMP_MODE without enabling skip frame

  With the configuration :

  av_dict_set(&options, "allow_skip_frames", "1", 0);

  I could get rid of this warning, but the movie still does not play. Are there other options that need to be set so that the movie plays in Windows Media Player ?

  Thank you for your help

  ffprobe output of the file that does play fine in Windows Media Player :

  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'test_x264.mp4':
  
    Metadata:
  
      major_brand     : isom
  
      minor_version   : 512
  
      compatible_brands: isomiso2avc1mp41
  
      title           : retina
  
      encoder         : Lavf57.56.100
  
      comment         : Creation Date: 2017-03-10 07:47:39.601
  
    Duration: 00:00:04.17, start: 0.000000, bitrate: 17497 kb/s
  
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661),
  
        yuv420p, 852x754, 17495 kb/s, 24 fps, 24 tbr, 24k tbn, 48 tbc (default)
  
      Metadata:
  
        handler_name    : VideoHandler

  ffprobe output of the file that does not play in Windows Media Player :

  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'test_openh264.mp4':
  
    Metadata:
  
      major_brand     : isom
  
      minor_version   : 512
  
      compatible_brands: isomiso2avc1mp41
  
      title           : retina
  
      encoder         : Lavf57.56.100
  
      comment         : Creation Date: 2017-03-10 07:49:27.024
  
    Duration: 00:00:04.17, start: 0.000000, bitrate: 17781 kb/s
  
      Stream #0:0(und): Video: h264 (Constrained Baseline) (avc1 / 0x31637661),
  
        yuv420p, 852x754, 17779 kb/s, 24 fps, 24 tbr, 24k tbn, 48k tbc (default)
  
      Metadata:
  
        handler_name    : VideoHandler

• FFMPEG MP3 file size much larger than expected on Windows 10

  8 avril 2018, par The Gora

  I’ve been using FFMPEG on Windows to :

  1. Convert iTunes M4A files to MP3s (with a bit rate of 128k) ; and
  2. Create 30 sec sample MP3s of the above MP3s (same bit rate).

  When I run FFMEG on a Windows 7 64 bit machine, the size of the MP3s (both for 1. & 2.) is in line with the rough calculation of :

  (Audio length in seconds) X (Bit rate)

  For example, a 4 minute audio yields an approx. 3.7MB MP3 file ; a 30 second sample MP3 is approx. 470KB.

  However when I run the same FFMPEG binary (copied from the Windows 7 machine) on a Windows 10 64 bit machine, all of the MP3s (both for 1. and for 2.) are inflated by approx 5MB. I’m using the same batch file on both machines to execute FFMEG with the required parameters, so pretty confident the difference is not down to user error.

  My questions are :

  1. Why is there this apparent 5MB overhead on Windows 10 ? and more importantly ;
  2. What can I do to remove this ?

  The large file size is a problem as the sample MP3s are to be put on a website for people to listen to a snippet of the song, and the webpage with multiple tags takes a long time to load completely (several minutes).

  Here is the version and lib info :

  ffmpeg version 3.4.1 Copyright (c) 2000-2017 the FFmpeg developers
 built with gcc 7.2.0 (GCC)
 configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-bzlib --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-cuda --enable-cuvid --enable-d3d11va --enable-nvenc --enable-dxva2 --enable-avisynth --enable-libmfx
 libavutil      55. 78.100 / 55. 78.100
 libavcodec     57.107.100 / 57.107.100
 libavformat    57. 83.100 / 57. 83.100
 libavdevice    57. 10.100 / 57. 10.100
 libavfilter     6.107.100 /  6.107.100
 libswscale      4.  8.100 /  4.  8.100
 libswresample   2.  9.100 /  2.  9.100
 libpostproc    54.  7.100 / 54.  7.100

  And here are the command lines I’m using :

  1. ffmpeg -i input.m4a -id3v2_version 3 -b:a 128k -output.mp3
  2. ffmpeg -i input.m4a -ss 30 -t 30 -af "afade=in:st=30:d=5,afade=out:st=55:d=5" -id3v2_version 3 -b:a 128k -output.mp3

• Run ffmpeg on windows

  14 juillet 2020, par Nikola Lukic

  I got successed on macos and linux with :

  


  Linux :

  


  ffmpeg \
    -f v4l2 \
    -framerate 25 -video_size 640x480 -i /dev/video0 \
    -f mpegts \
    -codec:v mpeg1video -s 640x480 -b:v 1000k -bf 0 \
    http://localhost:8081/supersecret


  


  MacOS test :

  


    ffmpeg -f avfoundation -framerate 30 -video_size 640x480 \
  -i "0" -f mpegts -codec:v mpeg2video -s 640x480 -b:v 1000k \
  -bf 0 http://localhost:8081/supersecret


  


  I already installed ffmpeg on windows a just need correct command.

  


  My error log is :

  


  


  /dev/video0: No such file or directory