pixlwave/waveform

An interactive audio waveform made with SwiftUI.

Waveform

A SwiftUI Package to display an interactive waveform of an audio file.

The project is currently in a very early stage having been created as part of SwiftUI Jam 2021. Code from the end of the Jam will be in the swiftuijam branch.

Installation

To include it in your Xcode project click File | Swift Packages | Add Package Dependency… and enter the following url:

https://github.com/pixlwave/Waveform

For now, you'll need to select Branch and ensure it's set to main until v0.1.0 is released.

Usage

To use Waveform create a WaveformGenerator object with your audio file:

let audioFile = try! AVAudioFile(forReading: URL))!
let generator = WaveformGenerator(audioFile: audioFile)   // this generator object is observable

And then pass this to a Waveform along with a selection range if you need this:

var body: some View {
    Waveform(generator: generator, selectedSamples: $selection, selectionEnabled: .constant(true))
}

The colour scheme can be customised via the standard colour modifiers:

Waveform(generator: generator, selectedSamples: $selection, selectionEnabled: .constant(true))
    .foregroundColor(waveformColor)
    .background(backgroundColor)
    .accentColor(selectionColor)

Caveats

• More work is required on optimisation for acceptable performance on older devices.
• Any audio file you use is loaded into memory in the WaveformGenerator. For now it would be worth watching your app's memory usage until this is addressed.

waveform's Issues

Playhead

Styling

• Foreground
• Background

Pinch to Zoom

Importing to swift playground iPad issue.

Hi there, thanks for the framework. I’d like to use it with swift playground iPad. It doesn’t work because the release tags has the "v" prefix. In your case “iOS(.v14)”. would it be possible if you could change that? Removing the “v” should fix the issue.

Highlighting

Interruptible rendering

Use vDSP to generate WaveformData

Handle Errors

• AVAudioPCMBuffer initialiser
• AVAudioFile.read(into:)

These are both in the WaveformGenerator object now.

Investigate Channel Summing

• Average?
• Power algorithm?

Fatal error: Index out of range on setting the `selectedSamples`

Hey 👋🏻 I'm getting Fatal error: Index out of range exception on setting the selectedSamples range like so:

Waveform(
  generator: generator,
  selectedSamples: $selectedSamples,
  selectionEnabled: .constant(true)
)
.foregroundColor(.white)
.onAppear {
  selectedSamples = 0 ..< Int(generator.audioBuffer.frameLength)
}

What could be the issue?

Convert into a Swift Package

Documentation

Should SampleRange be a ClosedRange?

Investigate whether AVAudioPCMBuffer will ever have intChannelData

Gestures only work over the WaveformRenderer

This is fixed now with a barely visible rect behind the view. Is there a better way to do this?