Recherche avancée

Sur d’autres sites (12131)

• How to apply audio equalization using NAudio

  19 mai 2021, par Raheel Khan

  I have a WPF app that does the following :

  


  

  1. Imports video files.

  


  2. Extracts audio from the using FFmpeg.

  


  3. Resamples the audio using NAudio to conform to a Speech-to-Text engine (16kHz/16bit/Mono).

  


  4. Plays back the video for users with overlayed subtitles.

  


  5. Allows users to correct mistakes that the STT engine might have made.

  


  


  Simple resampling with NAudio :

  


  using (var reader = new WaveFileReader(fileAudioTemp.FullName))
{
    var outFormat = new WaveFormat(16000, 16, 1);
    //var outFormat = WaveFormat.CreateIeeeFloatWaveFormat(16000, 1);

    using (var resampler = new MediaFoundationResampler(reader, outFormat))
    {
        resampler.ResamplerQuality = 60; // Highest Quality in MF.
        WaveFileWriter.CreateWaveFile(fileAudio.FullName, resampler);
    }
}


  


  The problem is that these videos have extremely bad audio quality. The sound is muffled, bassy, and makes it very difficult to make out names of people, places, etc. This makes it difficult and time-consuming for users to proof the text. Please do note that the STT engine has no problem with this and is surprisingly accurate considering the quality.

  


  What I would like to do is apply an equalization present to this audio. I found that the built-in SKA preset in VLC seems to make it 'slightly' easier for users to understand what is being said.

  


  

  


  Is there a way to use either FFmpeg (Xabe) or preferably NAudio to apply such a filter ? Is so how ? I have seen many examples out there about manipulation of sound buffers but was looking for an easier way such as a preset file or parameters that could be passed into the resamplers.

  


  Any pointers would be appreciated.

  


• moviepy mp4 to mp3 converter

  18 mai 2023, par Enspist

  I am trying to use python to convert files from mp4 to mp3. After some research most places recommend moviepy. I used the command pip install moviepy and it seemed to go off without a hitch. I go to VS Code and enter what a youtube video told me to enter (I know its not recommended to do that, I just wanted to see if it would work). This is what I have

  


  #This code should convert a .mp4 file into a .mp3 file

#This imports the moviepy package
from moviepy.editor import *

#here are the names of my files (I have subbed out actual files names)
mp4_file = "file_name.mp4"

mp3_file = "file_name.mp3

#Here is the the audio being stripped from the .mp4 file
video_clip = VideoFileClip(mp4_file)
audio_clip = video_clip.audio

#this is writing the audio to a .mp3 file at the path that is specified.
audio_clip.write_audiofile(mp3_file)

#this closes the conversion code
audio_clip.close()
VideoClip.close()


  


  After running the code I get this error :

  


  RuntimeError: No ffmpeg exe could be found. Install ffmpeg on your system, or set the IMAGEIO_FFMPEG_EXE environment variable.


  


  There is a bunch of gibberish above it but that is the final line that gets spit out.

  


  After looking up what the issue is I tried to input :

  


  from moviepy.config import change_settings
change_settings({"FFMPEG_BINARY": "/usr/bin/ffmpeg"})


  


  And it also did not work. I have tried searching for where ffmpeg is and it is not in /usr/bin/ffmepg or /usr/local/bin/ffmpeg like most sources I have looked at tell me it should be.

  


  I have tried installing ffmpeg on its own by doing pip install ffmpeg and 'brew install ffmpeg'. Both of those go off without a hitch as well but the error still pops.

  


  I am using a macbook air m1 and I have I think everything I need installed already so I am so lost on what is causing this error to pop.

  


  Can someone please help ?

  


  I have tried installing ffmpeg on its own as well as searching for the file directly.

  


  I should expect to get the .py file to run fine.

  


  I instead get the error seen above :

  


  RuntimeError: No ffmpeg exe could be found. Install ffmpeg on your system, or set the IMAGEIO_FFMPEG_EXE environment variable.


  


• avformat : Add av_get_frame_filename2() and AV_FRAME_FILENAME_FLAGS_MULTIPLE

  3 août 2016, par Michael Niedermayer

  avformat : Add av_get_frame_filename2() and AV_FRAME_FILENAME_FLAGS_MULTIPLE
  This will be used to allow writing file sequences using the tee output onto
  
  multiple places in parallel
  Signed-off-by : Michael Niedermayer <michael@niedermayer.cc>
  

  • [DH] doc/APIchanges
  • [DH] libavformat/avformat.h
  • [DH] libavformat/utils.c
  • [DH] libavformat/version.h