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• mplayer output 4 audio channels to jack

  14 novembre 2013, par MrCastro

  I am struggling with getting mplayer to reproduce a 4 audio channel wav file.

  I created a 4chn audio file. Want mplayer to player, and output it to jack. The problem is that i am only able to get in jack 2 mplayer channels.

  if I do:

  mplayer -ao jack -channels 4 test_4chan_2.wav 
  

  mplayer plays and responds:

  laying test_4chan_2.wav.
  libavformat version 54.6.100 (internal)
  Audio only file format detected.
  Load subtitles in ./
  ==========================================================================
  Opening audio decoder: [pcm] Uncompressed PCM audio decoder
  AUDIO: 44100 Hz, 4 ch, s16le, 2822.4 kbit/100.00% (ratio: 352800->352800)
  Selected audio codec: [pcm] afm: pcm (Uncompressed PCM)
  ==========================================================================
  AO: [jack] 44100Hz 2ch floatle (4 bytes per sample)
  Video: no video
  Starting playback...
  

  and jack has only the following outputs:

  system:capture_1
  system:capture_2
  system:playback_1
  system:playback_2
  MPlayer [14434]:out_0
  MPlayer [14434]:out_1
  

  So it seems that mplayer recognizes that the input file as 4ch but on AO: [jack] only 2ch appear

  if I try the same with ecasound:

  ecasound -f 16,4,44100 -i test_4chan_2.wav -o jack 
  

  in Jack ecasoud appears with 4 outputs

  system:capture_1
  system:capture_2
  system:playback_1
  system:playback_2
  ecasound:out_1
  ecasound:out_2
  ecasound:out_3
  ecasound:out_4
  

  Do you have any idea of what could I be doing wrong?? I am running Debian (Jessy) and mplayer 1.1-4.7

  Thanks a lot

• Extract WAV from an MP4, process and then remux it back

  13 novembre 2013, par Matt J.

  I have a large number of x264+AAC MP4 files. I have written an audio filter that operates on PCM wav files that I want to apply to the audio on all my videos, replacing the existing audio with the filtered version.

• Hide system message while running ffmpeg

  13 novembre 2013, par Irene T.

  I am using the code bellow to grab an image from a video file and it is working great. But when i am running the php file that contains the code bellow all system procceses appears, and i mean some infos about the convertion, export etc.

  How can i make it run silent?

  $stderr = system("ffmpeg -i $videoPath -vframes 1 -an -s 306x173 -ss 03 $finalfilename 2>&1 >/dev/null", $exit_status);
  
  if ($exit_status === 0) {
      print 'Done! :)';
  } else {
      print 'Error... :/';
      // $stderr will help you figure out what happened...
  }
  

• Find absolute path to ffmpeg

  13 novembre 2013, par Irene T.

  I installed ffmpeg and ffmpeg-php to my dedicated server and with a small script i am trying to extract an image from specific second.

  <?php
  
  $extension = "ffmpeg";
  $extension_soname = $extension . "." . PHP_SHLIB_SUFFIX;
  $extension_fullname = PHP_EXTENSION_DIR . "/" . $extension_soname;
  
  $timeOffset = "00:00:30";
  $videoPath = "sample.mp4";
  $extensi = ".jpg";
  $folder = "images/";
  $finalfilename = $folder . $randomfilename . $extensi;
  
  echo $extension_fullname; //I AM GETING THIS /usr/lib64/php/modules/ffmpeg.so
  
  if (exec("ffmpeg -ss $timeOffset -i $videoPath  -frames:v 1 $finalfilename")){
  echo "Done";
  }else{
  echo "Error";   
  }
  ?>
  

  as you can see in my execution command ther is ffmpeg, but how can i find the absolute path to ffmpeg? Take a look in my screenshot maybe this helps you to tell me..

  My last question is what is ffmpeg-php? Do i need it? i already install it.

  Thank you

  

• PHP - Converting images to video using ffmpeg

  13 novembre 2013, par Vishnu

  I am good in php but very new to ffmpeg and exec stuffs.Now I have successfully installed ffmpeg via ssh.I referred some stackoverflow here and found below code to make video using several images.

  <?php
  
  echo exec('ffmpeg -f image2 -i image%d.jpg video.mpg');
  
  ?>
  

  I have image1.jpg and image2.jpg in same folder.I run this php code but nothing happened...where does video.mpg gets saved ? and how to check if exec function ran successfully or how to debug it ?Any help is appreciated.