Recherche avancée

Sur d’autres sites (4742)

• ffmpeg 2nd pass segfault [migrated]

  25 février 2014, par Mike Flynn

  I'm trying to get an old transcoding server up and running in a new environment and I'm experiencing some issues getting the well tested ffmpeg commands to work in the new environment.

  It's a 2 pass encoding strategy, and the first pass runs just fine every time, the 2nd pass consistently fails with the following :

  [libx264 @ 0x3925fc0] 2nd pass has more frames than 1st pass (1478)
  
  [libx264 @ 0x3925fc0] continuing anyway, at constant QP=14
  
  [libx264 @ 0x3925fc0] disabling adaptive B-frames
  
  [libx264 @ 0x3925fc0] specified frame type is not compatible with max B-frames
  
  Segmentation fault

  Here is the command we're using for each pass :

  Pass 1 :

  ffmpeg -y -i input.mp4 -pass 1 -b 774000 -ab 128000 -s 640x360 -passlogfile ffmpeglog -vcodec libx264 -g 90 -bf 3 -refs 1 -b_strategy 1 -coder 1 -qmin 10 -qmax 51 -sc_threshold 40 -flags +loop -cmp chroma -me_range 16 -me_method dia -subq 2 -i_qfactor 0.71 -qcomp 0.6 -qdiff 4 -direct-pred 3 -trellis 0 -partitions -parti8x8-parti4x4-partp8x8-partb8x8 -r 30 -keyint_min 25 -wpredp 2 -rc_lookahead 50 -acodec libfaac -ar 44100 pass1.mp4

  Pass 2 :

  ffmpeg -y -i pass1.mp4 -pass 2 -b 774000 -ab 128000 -s 640x360 -passlogfile ffmpeglog -vcodec libx264 -g 90 -bf 3 -refs 8 -b_strategy 1 -coder 1 -qmin 10 -qmax 51 -sc_threshold 40 -flags +loop -cmp chroma -me_range 16 -me_method umh -subq 9 -i_qfactor 0.71 -qcomp 0.6 -qdiff 4 -direct-pred 3 -trellis 2 -partitions +parti8x8+parti4x4+partp8x8+partp4x4+partb8x8 -r 30 -keyint_min 25 -wpredp 2 -rc_lookahead 60 -acodec libfaac -ar 44100 pass2.mp4

  ...and here is my ffmpeg configuration :

  ffmpeg version 2.1.4 Copyright (c) 2000-2014 the FFmpeg developers
  
    built on Feb 25 2014 19:23:21 with gcc 4.6.3 (GCC) 20120306 (Red Hat 4.6.3-2)
  
    configuration: --enable-gpl --enable-libmp3lame --enable-libtheora --enable-libvo-aacenc --enable-libvorbis --enable-libvpx --enable-libx264 --enable-version3 --enable-libfaac --enable-nonfree
  
    libavutil      52. 48.101 / 52. 48.101
  
    libavcodec     55. 39.101 / 55. 39.101
  
    libavformat    55. 19.104 / 55. 19.104
  
    libavdevice    55.  5.100 / 55.  5.100
  
    libavfilter     3. 90.100 /  3. 90.100
  
    libswscale      2.  5.101 /  2.  5.101
  
    libswresample   0. 17.104 /  0. 17.104
  
    libpostproc    52.  3.100 / 52.  3.100
  
  Hyper fast Audio and Video encoder
  
  usage: ffmpeg [options] [[infile options] -i infile]... {[outfile options] outfile}...

  Any ideas would be greatly appreciated !

• lowest latency method to pass raw video frames from ffmpeg to gstreamer

  21 juillet 2021, par art vanderlay

  I would like to pass raw audio and video buffers from ffmpeg to gstreamer. For video a 1920x1080 25fps RGB output is what ffmpeg is producing.

  


  What is the best method to pass this from ffmpeg to gstreamer on the same hardware.

  


  The end goal is to not block either ffmpeg from outputting if gstreamer cannot take the frame and to not block gstreamer if no frames are available.

  


  For this we have looked at sockets and tcp/udp plugins. However if we get any buffering issues the gstreamer pipline will block until the buffer is clear/full.

  


  we will have multiple pairs of TX/RX running on same linux instance so stdI/O will not work.
Is there a current preferred method for this type of transfer ?

  


• how to pass a audio file with powershell pipe [duplicate]

  9 février 2020, par mudssky

  I’m trying to convert flac file to aac use qaac cli.
  qaac cli default don’t support flac file,so i use ffmpeg to convert it to wav ,and use pipe pass it to qaac

  this command can be run successfully in cmd
  ffmpeg.exe  -i .\input.flac  -f wav -| qaac64.exe -

  but in powershell ,the pipe passed string object,so it doesnt’t work properly
  ffmpeg.exe  -i .\input.flac  -f wav -| get-member

  Q : what’s the correct way in powershell to pass a file ?