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• python : subprocess call ffmpeg (command line)

  21 septembre 2014, par user3295674

  I have been incorporating subprocess calls in my program. I have had no issues with subprocess calls for other commands, but I am having trouble getting the command line input

  ffmpeg -r 10 -i frame%03d.png -r ntsc movie.mpg
  

  To work inside a subprocess.call()

  I tried the following with no success:

  subprocess.call('ffmpeg -r 10 -i %s frame%03.d.png - r ntsc movie.mpg')
  

  Any thoughts? Do I separate out different commands, do I specify string, integer etc. with %s, %d?

• FFmpeg : Get volume of frame or short timespan

  21 septembre 2014, par Qaz

  I want to make a program that automatically deletes frames from an mp4 when the volume for those frames is below a given threshold. How can I get the volume of each frame? Or, alternatively, the volume for time t in the video? Or for timespan dt? (I'm not committed to FFmpeg yet, or even to the mp4 format, so feel free to suggest alternatives.)

• Executing ffmpeg command using Popen

  21 septembre 2014, par dragonator

  I have a strange problem trying to execute ffmpeg command using Popen. I have the following piece of code, which I use for executing an external commands in Python:

  from subprocess import Popen, PIPE
  from datetime import datetime
  
  
  class Executor(object):
  
      @classmethod
      def execute(cls, command):
          """
          Executing a given command and
          writing into a log file in cases where errors arise.
          """
          p = Popen(command, stdin=PIPE, stdout=PIPE, stderr=PIPE)
          output, err = p.communicate()
          if p.returncode:
              with open("failed_commands.log", 'a') as log:
                  now = datetime.now()
                  log.write('{}/{}/{} , {}:{}:{}\n\n'.format(now.day, now.month,
                                                             now.year, now.hour,
                                                             now.minute,
                                                             now.second))
  
                  log.write("COMMAND:\n{}\n\n".format(" ".join(command)))
                  log.write("OUTPUT:\n{}\n\n".format(output.decode("utf-8")))
                  log.write("ERRORS:\n{}\n".format(err.decode("utf-8")))
                  log.write('-'*40)
                  log.write('\n')
  
              return ''
  
          if not output:
              output += ' '
  
          return output
  

  I've tested it with others commands, but when I try to execute ffmpeg command - it fails. I'm trying to convert some audio format to mp3 format. Here is an example of my command:

  ffmpeg -i "/path/old_song.m4a" "/path/new_song.mp3"
  

  ...simple as that.When I run it in terminal it works fine, but when I try to execute it using the above function it fails. Here is the exact error:

  ----------------------------------------
  21/9/2014 , 19:48:50
  
  COMMAND:
  ffmpeg -i "/path/old_song.m4a" "/path/new_song.mp3"
  
  OUTPUT:
  
  
  ERRORS:
  ffmpeg version 2.2.3 Copyright (c) 2000-2014 the FFmpeg developers
    built on Jun  9 2014 08:01:43 with gcc 4.9.0 (GCC) 20140521 (prerelease)
    configuration: --prefix=/usr --disable-debug --disable-static --enable-avisynth --enable-avresample --enable-dxva2 --enable-fontconfig --enable-gnutls --enable-gpl --enable-libass --enable-libbluray --enable-libfreetype --enable-libgsm --enable-libmodplug --enable-libmp3lame --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-librtmp --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libv4l2 --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libxvid --enable-pic --enable-postproc --enable-runtime-cpudetect --enable-shared --enable-swresample --enable-vdpau --enable-version3 --enable-x11grab
    libavutil      52. 66.100 / 52. 66.100
    libavcodec     55. 52.102 / 55. 52.102
    libavformat    55. 33.100 / 55. 33.100
    libavdevice    55. 10.100 / 55. 10.100
    libavfilter     4.  2.100 /  4.  2.100
    libavresample   1.  2.  0 /  1.  2.  0
    libswscale      2.  5.102 /  2.  5.102
    libswresample   0. 18.100 /  0. 18.100
    libpostproc    52.  3.100 / 52.  3.100
  "/path/old_song.m4a": No such file or directory
  Conversion failed!
  
  ----------------------------------------
  

  ...and as you can think of - the file exists.

  I think there is something in passing the command to Popen.communicate but I don't know exactly.

  Kind regards,

  Teodor D. PS: I'm passing the command to Executor.execute as Python list.

  PSS: Calling the Executor.execute :

  def process_conversion(self):
      for song in self.files_to_convert:
          current_format = song.rsplit('.', 1)[-1]
  
          old_file = '"{}{}{}"'.format(self.target_dir, os.sep, song)
          new_file = '"{}{}{}"'.format(self.target_dir, os.sep,
                                       song.replace(current_format, 'mp3'))
  
          command = ["ffmpeg", "-i", old_file, new_file]
          Executor.execute(command)
  

• ffmpeg install php 5.6.11 xampp window 7 32bit [on hold]

  21 septembre 2014, par yogesh kumar

  I am install ffmpeg but it is provide all detail fulfill below description but not install these error come when we start xampp server how can resolve it ![enter image description here][1] but it is provide error

  some time below error is comming

  Please give me you suggestion/answer

• Using ffmpeg in Java

  21 septembre 2014, par Riccardo Bestetti

  I'm writing a Java program. I'm receiving a MPEG video stream via TCP and I have to decode it and re-encode it in a different format.

  I have found JJMPEG, which are ffmpeg wrappers for Java, but they don't get an update since 2 years ago. So I thought to implement my conversion by spawning a ffmpeg process from Java and piping the stream into it, and getting the data back from another pipe.

  Would that be a optimal solution? I need feedback from experienced people on both Java and ffmpeg programming.