Recherche avancée

Sur d’autres sites (7948)

• fluent-ffmpeg concatenate audio files

  8 septembre 2020, par Martin

  I am trying to use fluent-ffmpeg with my electron app to concatenate multiple audio files together with an image in a video. So if i have three files :

  


  song1.mp3 1:00
song2.mp3 0:30
song3.mp3 2:00
front.jpg

  


  I could create output.mp4 which would be 3:30 seconds long, and play each file one after the other in order. With front.jpg set as the background image.

  


  I have succesfully been able to render a single audio file with an image file, but havent been able to render multiple audio files together yet into a video.

  


  Here is my concat attempt :

  


  const command = ffmpeg();
       
            const audioFiles = ['C:\\Users\\marti\\Documents\\martinradio\\uploads\\Movers - 1970 greatest hits vol. 2\\01 back from the moon.mp3', 'C:\\Users\\marti\\Documents\\martinradio\\uploads\\Movers - 1970 greatest hits vol. 2\\02 love me not.mp3'];
            audioFiles.forEach((fileName)=>{
                command.input(fileName);
            })
            command
                    .complexFilter([
                        '[0]adelay=1000|1000[a]',
                        '[1]adelay=4000|4000[b]',
                        '[a][b]amix=2'
                    ])
                    .input(imgPath)
                    .videoCodec('copy')
                    .save('C:\\Users\\marti\\Documents\\martinradio\\uploads\\Movers - 1970 greatest hits vol. 2\\concat-autio.mp4')
                    .on('codecData', function(data) {
                        console.log('codecData=',data);
                    })
                    .on('progress', function({ percent }) {
                        console.log('progress percent: ' + percent);
                    })
                    .on('end', function() {
                        console.log('file has been converted succesfully');
                    })
                    .on('error', function(err) {
                        console.log('an error happened: ' + err.message);
                    })
                    command.run()


  


  When I run it I can see in my console it start, run, and end.

  


  

  


  My example uses two audio files :

  


  01 back from the moon.mp3 02:31
02 love me not.mp3' 02:35

  


  So my output file should be 05:06 in length, but my output is only 02:39 in length


  


• Heroku django weird tempfile behavior

  13 février 2019, par BenFire

  I’m writing a django application, where, a user records a message, the message is converted with FFMPEG and uploaded to a FS,now, FFMPEG doesn’t allow file overwrite, so i’m creating a new file and than replacing the old one before inserting it my filesystem. so basically :

  The file is recorded in the front-end -> sent to the backend and stored as a tempfile (automatically by django) -> the files gets converted -> the file is uploaded to the fs.

  (the file is converted from around 2mb to 200kb, which is an indicator to if the file was converted)

  now, to replace the original file, I use shutil.move(), and when i run it on my system, and then I look in my fs, the file sure is only 200kb, but when i push the same code to Heroku, i do the same operation, when look in the fs I see that the new file is still 2mb, also, I know the conversion was done from the server logs, whitch means that the file replacing failed but only on Heroku, am i missing something ?

• dts to m4a (aac) encoding - qaac, neroaacenc encoder output issues

  9 avril 2014, par user8979

  greets

  I want to encode a dts 5.1 audio source to m4a (aac) 5.1 with same playback duration.
  Intend to use either qaac or neroAacEnc.

  The output is the same per encoder with .mkv and .dts extracted from .mkv as input audio source.
  .mkv source piped to encoder using ffmpeg
  .dts source piped to encoder using ffmpeg and wavi with .avs input, .avs using NicAudio avisynth plugin, to decode .dts source for separate encodes to confirm if challenges encountered were from ffmpeg or elsewhere (both produced the same issues so concluded the issues originated from the respective encoders)

  • qaac output is same duration as .mkv
    issues : mediainfo reports output is 2ch while mediatab and ffmpeg report output is 5.1ch (lfe)

    mediainfo :

    Channel(s) : 2 channels
    Channel(s)_Original : 6 channels
    Channel positions : Front : L C R, Side : L R, LFE
    this channel position and channel combination is not possible, so which is it ?

    ffmpeg (5.1 info bold) :

    Stream #0:0(und) : Audio : aac, 5.1, fltp

    mediatab :

    Channel(s) : 6 channels
    ChannelPositions : Front : L C R, Side : L R, LFE

  • neroaacenc output has same channels, 5.1
    issue : ffmpeg reports output is longer than mkv audio track by 0.06 seconds (60 ms) and it begins after 0.054677 seconds (54.667 ms)

    Chapter #0.0 : start 0.054667

  Questions :

  1. qaac output
     
     • is the output stream 2ch or 5.1ch ?
     • if it is 2ch, what qaac option(s) leave the channels in output same as input AND report the correct channels ?
     • if the output is 5.1ch, does this mean every qaac output keeps the input channels (without using —chanmap or other such options) ? if so then its easy to ignore mediainfo channel information for qaac encodes.
       
       • why did mediainfo report 2ch ? could the stream report incorrect channels to a media player (implies incorrect playback) ? is there any way to get rid of the misleading channel information shown in mediainfo ? (expecting the information to be stored in the file, that is where would like to get rid of it)
  2. neroaacenc output
     • how can one ensure neroaacenc output is exact same duration as input ?
     • if not possible to change the output duration, does that mean when muxing audio with video, include the 54.667 ms delay to maintain sync ? (audio delay of -0.054667 s in this case) ?

  Commandlines were many so not included. Let me know if they would be helpful.