Recherche avancée

Sur d’autres sites (6592)

• How to detect two identical audio/video files with different volume level ?

  3 juillet 2017, par Marina Rappoport

  I’m working on program that could compare 2 video files and show difference.
  I compare audio track of files using SOX and FFMPEG :

  1. invert one of the files (sox)
  2. merge other file and invert version of first (sox)
  3. detect silence (ffmpeg)

  But if two file differs only by volume level - all audio track will be detected as non-silent ranges.

  How to understand that 2 files have the same audio track, but with different volume level ?

  I tried to change sound level via sox : sox -v 1.1 input.wav output.wav
  And then compare statistical information (-n stat).
  It works fine. Result of division parameters audio2/audio1 :

      Samples read 1.00;
  
      Length (seconds) 1.00;
  
      Scaled by 1.00;
  
      Maximum amplitude 1.10;
  
      Minimum amplitude 1.10;
  
      Midline amplitude 1.10;
  
      Mean norm 1.10;
  
      Mean amplitude 1.00;
  
      RMS amplitude 1.10;
  
      Maximum delta 1.10;
  
      Mean delta 1.10;
  
      RMS delta 1.10;
  
      Rough frequency 1.00;
  
      Volume adjustment 1/1.10;

  BUT ! When I tried ffmpeg to change volume of video : ffmpeg -i input.mp4 -vcodec copy -af "volume=10dB" output.mp4 (or volume=volume=0.5) and than compared sox audio statistic : I can’t find any patterns...

  Samples read    1.00
  
  Length (seconds)    1.00
  
  Scaled by   1.00
  
  Maximum amplitude   0.71
  
  Minimum amplitude   0.64
  
  Midline amplitude   -2401.73
  
  Mean    norm    0.34
  
  Mean    amplitude   0.50
  
  RMS     amplitude   0.36
  
  Maximum delta   0.37
  
  Mean    delta   0.34
  
  RMS     delta   0.36
  
  Rough   frequency   0.99
  
  Volume adjustment   0.71

  I will be grateful for any ideas and help.

• Revision 8bd88a3c83 : Merge "Make RTC coding flow support sub8x8 in key frame coding"

  10 décembre 2014, par Jingning Han

  Merge "Make RTC coding flow support sub8x8 in key frame coding"

• FFMPEG mixing .wav files volume control [closed]

  1er avril 2024, par JoonSeo Yang

  I am working on Java, using the ffmpeg library with command line processing to mix 2 .wav files into one .wav file, but I would like to know how to control the volume of each original file.

  


  My problem : i have 2 audio files (human voice BGM), but BGM is too loud, so i can barely hear human voice, i would like to -> volume down the BGM file, or volume up voice file

  


  Here is my partial code

  


  String ffmpegCommand = file_exe.getAbsolutePath()
    + String.format(
        " -i %s -i %s -filter_complex amix=inputs=2:duration=first:dropout_transition=3 %s",
        file_1.getAbsolutePath(), file_2.getAbsolutePath(), outputFilePath);
Process process = Runtime.getRuntime().exec(ffmpegCommand);


  


  it is quite simple code. I need help on this, and it would be very thankful to which document to read to get such information

  


  PS.sorry for my poor eng.. Im not native :D

  


  I was wandering around documentations, but its quite hard to find what i want