Recherche avancée

Sur d’autres sites (14136)

• FFMPEG Manipulate the start time [duplicate]

  9 octobre 2018, par Sean

  This question already has an answer here :

  • Does PTS have to start at 0 ?
    
    1 answer
    

  I have an ISMV file (fragmented MP4) which has a set start time (an epoch time) which allows other metadata to synchronise with it.

  if I ffprobe it I get the following ;

  Duration: 00:44:00.28, start: 1537792418.761560, bitrate: 3970 kb/s

  Is it possible to manipulate the start time ?
  I have had to re-encode the file, and it’s start time is now zero.
  I have checked many options, but am really unclear what is possible.

  From what I see I should be looking at a filter with the pts options. But I’m unclear what it should actually be after many hours of searching and fiddling ?

  Cheers in advance.

• How to do multiple input with streamio-ffmpeg ?

  12 août 2020, par Yozuu

  I would like to recreate this ffmpeg line (which works well) in my rails app :

  


  ffmpeg -i 1.mp4 -i 2.mp4 -filter_complex '[0] [1] afir=dry=10:wet=10' output.wav


  


  So here is my config :

  


  module EncodingConstants
  PROCESSED_DEFAULTS = {
    resolution:           '500x400',
    video_codec:          'libx264',
    constant_rate_factor: '30',
    frame_rate:           '25',
    audio_codec:          'aac',
    audio_bitrate:        '128k',
    audio_sample_rate:    '48000',
    progress: :processing_progress
  }.freeze

  AUDIO_EFFECTS = {
    multi_effect: %w[-i /home/yozuu/2.mp4 -filter_complex [0] [1] afir=dry=10:wet=10]
 }.freeze


  


  So Sidekiq send this back to me :

  


  I, [2020-08-12T19:40:38.828081 #2142]  INFO -- : Running transcoding...
["/sbin/ffmpeg", "-y", "-i", "/home/yozuu/labo/video-project/tmp/1597254011-2142-0001-8820/1.mp4", "-vcodec", "libx264", "-acodec", "aac", "-s", "500x282", "-i", "/home/yozuu/2.mp4", "-filter_complex", "'[0]", "[1]", "afir=dry=10:wet=10'", "-r", "25", "-b:a", "128k", "-ar", "48000", "-aspect", "1.7730496453900708", "/home/yozuu/labo/video-project/tmp/1597254011-2142-0001-8820/1.mp4"]

E, [2020-08-12T19:40:38.897575 #2142] ERROR -- : Failed encoding...
["/sbin/ffmpeg", "-y", "-i", "/home/yozuu/labo/video-project/tmp/1597254011-2142-0001-8820/1.mp4", "-vcodec", "libx264", "-acodec", "aac", "-s", "500x282", "-i", "/home/yozuu/2.mp4", "-filter_complex", "'[0]", "[1]", "afir=dry=10:wet=10'", "-r", "25", "-b:a", "128k", "-ar", "48000", "-aspect", "1.7730496453900708", "/home/yozuu/labo/video-project/tmp/1597254011-2142-0001-8820/1.mp4"]


.....

Unknown decoder 'libx264'

Errors: no output file created. 



  


  I don't understand why because for me the command line ffmpeg seems correct.
Anyone have a idea ?
Thank you.

  


• Can't list input devices ffmpeg linux

  23 juillet 2021, par spindi598

  On windows I could do something like this to list input devices :

  


  ffmpeg -list_devices true -f dshow -i dummy


  


  On Linux I try doing something like this :

  


  ffmpeg -list_devices true -f <x11grab></x11grab>avfoundation>&#xA;

  


  And I get an error (I have also tried the latest git build from here) :

  


  ffmpeg version n4.2.4 Copyright (c) 2000-2020 the FFmpeg developers
  built with gcc 10.1.0 (GCC)
  configuration: --prefix=/usr --disable-debug --disable-static --disable-stripping --enable-avisynth --enable-fontconfig --enable-gmp --enable-gnutls --enable-gpl --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libdav1d --enable-libdrm --enable-libfreetype --enable-libfribidi --enable-libgsm --enable-libiec61883 --enable-libjack --enable-libmfx --enable-libmodplug --enable-libmp3lame --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libssh --enable-libtheora --enable-libv4l2 --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxcb --enable-libxml2 --enable-libxvid --enable-nvdec --enable-nvenc --enable-omx --enable-shared --enable-version3
  libavutil      56. 31.100 / 56. 31.100
  libavcodec     58. 54.100 / 58. 54.100
  libavformat    58. 29.100 / 58. 29.100
  libavdevice    58.  8.100 / 58.  8.100
  libavfilter     7. 57.100 /  7. 57.100
  libswscale      5.  5.100 /  5.  5.100
  libswresample   3.  5.100 /  3.  5.100
  libpostproc    55.  5.100 / 55.  5.100
Unrecognized option 'list_devices'.
Error splitting the argument list: Option not found


  


  How can I list my input devices ?