infinity/kali

Time stretching and pitch shifting in Javascript

kali's Issues

Change tempo during stretching

Currently, you can only set tempo during setup. Ideally, you could change the tempo as you feed in more data and Kali would stretch as appropriate

Artefacts with multichannel audio

To verify these artefacts you can simply replace var output = doStretch(inputData, START_RATE); with var output = doStretch(inputData, START_RATE, 2); in your test.js file. The effect sounds like regular clicking artefacts (more or less apparent depending on the type of audio).

My workaround was to declare a single channel of data (although I guess the algorithm will result misconfigured in this case, even if the audio quality is still good). I can provide a complete example if you need to reproduce the issue.

Thanks.

Demo: MP3 Drag & Drop

The ability to simply drop an MP3 on the demo page seems to be broken. At least, in Firefox and Chrome it simply replaced the demo with the MP3 I was trying to upload.

Example for using Kali in real time that produce reasonably good audio

Hi !
I am currently trying to use your project in a realtime project. Audio should be processed and pushed to speakers without the latency of processing the whole track.

I am using the scriptPrecessorNode witch is feeding the Kali instance with the buffer given by the scriptProcessor.
Actualy it is working but the sound is very bad. You can listen the audio sample to understand a bit more what it sound like.

Here the code I use :

this.kali = new Kali(2);
this.setup(audioContext.sampleRate, 0.5);
input = audioContext.createScriptProcessor(4096, 1, 1);
that = this;
input.onaudioprocess = function (audioProcessingEvent) {
      var inputBuffer = audioProcessingEvent.inputBuffer;
      var outputBuffer = audioProcessingEvent.outputBuffer;

      var inputData = inputBuffer.getChannelData(0);

      var numInputFrames = inputData.length;
      var numChannels = 1;
      var stretchFactor = 1;

      var completed = new Float32Array(numInputFrames * numChannels + 1);

      that.kali.input(dataToInput);
      that.kali.process();
      that.kali.output(complete)
      that.kali.flush();

    outputBuffer.copyToChannel(completed, 0, 0);

  };

Any ideas of what I am doing wrong ?

Pitch shifting not yet implemented

Pitch shifting is implemented by resampling the audio and then doing time stretching

Using from NPM

Hi there. I've been trying to use your library from NPM by adding the following line into my package.json's 'dependencies':

"kali": "https://github.com/Infinity/Kali/archive/0.0.1.tar.gz",

However I'm having trouble importing it. I think the reason is that Kali's package.json is missing the 'main' parameter (https://docs.npmjs.com/files/package.json#main).

Should I fork the project and add it myself, or do you plan on adding Kali to the NPM registry soon?

Lastly, great library, thanks!

[edit] I got it working by using LucasThompson@b8c0f3f (thank you too, @LucasThompson)

Time-Stretching on the fly

Hi, one great feature I would love to have is to change time-stretching on the fly, without affecting the pitch. So you can speed up or slow down a song with a simple slider on a web page. Do you think it's feasable ?

Audio quality issues with multi-channel audio

There are currently issues with transforming multichannel audio