Recherche avancée

Sur d’autres sites (13273)

• Best way to pipe audio and video chunks from within python to ffmpeg

  8 mai 2016, par basilikum

  Problem

  I’m getting audio and video chunks from a third-party server and I would like to pipe those chunks to ffmpeg to create a WebM live stream according to these instructions :

  http://wiki.webmproject.org/adaptive-streaming/instructions-to-do-webm-live-streaming-via-dash

  Here they are using input from webcam and microphone but I need to use the data chunks, so the ffmpeg command would look somehow like this :

      cmd = [
  
          "ffmpeg",
  
          "-f", "flv", "-i", "video.fifo",
  
          "-f", "s16le", "-ar", "16000", "-ac", "1", "-i", "audio.fifo",
  
          "-map", "0:0",
  
          "-pix_fmt", "yuv420p",
  
          "-c:v", "libvpx-vp9",
  
          "-s", "640x480", "-keyint_min", "40", "-g", "40", "-speed", "6",
  
          "-tile-columns", "4", "-frame-parallel", "1", "-threads", "8",
  
          "-static-thresh", "0", "-max-intra-rate", "300",
  
          "-deadline", "realtime", "-lag-in-frames", "0",
  
          "-error-resilient", "1",
  
          "-b:v", "3000k",
  
          "-f", "webm_chunk",
  
          "-header", self.video_header,
  
          "-chunk_start_index", "1",
  
          "video_360_%d.chk",
  
          "-map", "1:0",
  
          "-c:a", "libvorbis",
  
          "-b:a", "16k", "-ar", "16000",
  
          "-f", "webm_chunk",
  
          "-audio_chunk_duration", "2000",
  
          "-header", self.audio_header,
  
          "-chunk_start_index", "1",
  
          "audio_171_%d.chk"
  
      ]

  As you can see, I am using a "video.fifo" and "audio.fifo" file, because I thought it would be a good idea to pipe the chunks in via a named pipe, but I can’t get it to work. Here is what I’m doing :

  p = subprocess.Popen(cmd)
  
  fa = os.open("video.fifo", os.O_WRONLY)
  
  fv = os.open("audio.fifo", os.O_WRONLY)

  So I’m starting the subprocess first, so that it opens the fifo files for reading. After that, I should be able to open them for writing but I am not. More specifically, I am able to open the first one, but not the second one. So maybe that has something to do with how ffmpeg handles its inputs if there are more than one, but I just don’t know.

  Question

  How can I either solve the problem of non openable named pipes or how can I achieve what I wanted to achieve without named pipes.

• lavf/img2dec : add pnm pipe demuxers

  8 juin 2016, par Clément Bœsch

  lavf/img2dec : add pnm pipe demuxers
  

  • [DH] libavformat/Makefile
  • [DH] libavformat/allformats.c
  • [DH] libavformat/img2dec.c
  • [DH] libavformat/version.h
  • [DH] tests/ref/seek/lavf-pbmpipe
  • [DH] tests/ref/seek/lavf-pgmpipe
  • [DH] tests/ref/seek/lavf-ppmpipe

• Getting 'av_interleaved_write_frame() : Broken pipe' error

  2 juillet 2016, par Poornan

  I am trying this blog post.I am new to python, numpy as well as FFMPEG. I could not figure out what causes this issue.

  http://zulko.github.io/blog/2013/09/27/read-and-write-video-frames-in-python-using-ffmpeg/

  here is the code :

  import subprocess as sp
  
  import numpy
  
  
  
  print ("Hello World!");
  
  FFMPEG_BIN = "ffmpeg" # on Linux ans Mac OS
  
  #FFMPEG_BIN = "ffmpeg.exe" # on Windows
  
  
  
  command = [ FFMPEG_BIN,
  
              '-i', '/Users/eananthaneshan/Movies/myvideo.mp4',
  
              '-f', 'image2pipe',
  
              '-pix_fmt', 'yuv444p',
  
              '-s', '420x360',
  
              '-r', '24',
  
              '-vcodec', 'h264', '-']
  
  pipe = sp.Popen(command, stdout = sp.PIPE, bufsize=-1)
  
  
  
  # read 420*360*3 bytes (= 1 frame)
  
  raw_image = pipe.stdout.read(420*360*3)
  
  # transform the byte read into a numpy array
  
  image =  numpy.fromstring(raw_image, dtype='uint8')
  
  image = image.reshape((360,420,3)   )
  
  # throw away the data in the pipe's buffer.
  
  pipe.stdout.flush()

  This is the output :

  ffmpeg version 2.8 Copyright (c) 2000-2015 the FFmpeg developers
  
    built with Apple LLVM version 7.0.0 (clang-700.0.72)
  
    configuration: --prefix=/usr/local/Cellar/ffmpeg/2.8 --enable-shared --enable-pthreads --enable-gpl --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-opencl --enable-libx264 --enable-libmp3lame --enable-libvo-aacenc --enable-libxvid --enable-libfreetype --enable-libtheora --enable-libvorbis --enable-libvpx --enable-librtmp --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libass --enable-ffplay --enable-libspeex --enable-libschroedinger --enable-libfdk-aac --enable-libopus --enable-frei0r --enable-libopenjpeg --disable-decoder=jpeg2000 --extra-cflags='-I/usr/local/Cellar/openjpeg/1.5.2_1/include/openjpeg-1.5 ' --enable-nonfree --enable-vda
  
    libavutil      54. 31.100 / 54. 31.100
  
    libavcodec     56. 60.100 / 56. 60.100
  
    libavformat    56. 40.101 / 56. 40.101
  
    libavdevice    56.  4.100 / 56.  4.100
  
    libavfilter     5. 40.101 /  5. 40.101
  
    libavresample   2.  1.  0 /  2.  1.  0
  
    libswscale      3.  1.101 /  3.  1.101
  
    libswresample   1.  2.101 /  1.  2.101
  
    libpostproc    53.  3.100 / 53.  3.100
  
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/Users/eananthaneshan/Movies/myvideo.mp4':
  
    Metadata:
  
      major_brand     : isom
  
      minor_version   : 1
  
      compatible_brands: isom
  
      creation_time   : 2014-04-07 02:02:31
  
    Duration: 01:00:10.03, start: 0.000000, bitrate: 1024 kb/s
  
      Stream #0:0(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 111 kb/s (default)
  
      Metadata:
  
        creation_time   : 2014-04-07 02:02:31
  
        handler_name    : GPAC ISO Audio Handler
  
      Stream #0:1(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv, bt709/unknown/unknown), 720x404, 909 kb/s, 23.98 fps, 23.98 tbr, 24k tbn, 47.95 tbc (default)
  
      Metadata:
  
        creation_time   : 2014-04-07 01:14:58
  
        handler_name    : L-SMASH Video Media Handler
  
        encoder         : AVC Coding
  
  Output #0, image2pipe, to 'pipe:':
  
    Metadata:
  
      major_brand     : isom
  
      minor_version   : 1
  
      compatible_brands: isom
  
      encoder         : Lavf56.40.101
  
      Stream #0:0(und): Video: rawvideo (444P / 0x50343434), yuv444p, 420x360, q=2-31, 200 kb/s, 23.98 fps, 23.98 tbn, 23.98 tbc (default)
  
      Metadata:
  
        creation_time   : 2014-04-07 01:14:58
  
        handler_name    : L-SMASH Video Media Handler
  
        encoder         : Lavc56.60.100 rawvideo
  
  Stream mapping:
  
    Stream #0:1 -> #0:0 (h264 (native) -> rawvideo (native))
  
  Press [q] to stop, [?] for help
  
  av_interleaved_write_frame(): Broken pipe
  
  frame=    2 fps=0.0 q=-0.0 Lsize=     886kB time=00:00:00.08 bitrate=87003.8kbits/s    
  
  video:886kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.000000%
  
  Conversion failed!