NgWaveform

Library to visualize audio waveform. Built as pure Angular library that doesn't wrap any of JS library. With NgWaveform you can create interactive customisable waveform of any audio file in your Angular application.

Quick start

npm install --save ng-waveform

import { NgWaveformModule } from 'ng-waveform';

import { ITimeUpdateEvent, NgWaveformComponent, IRegionPositions } from 'ng-waveform';
 
@ViewChild('waveform', { static: false }) waveform: NgWaveformComponent;
 
onPlayButtonClick() {
  this.waveform.play();
}
onPauseButtonClick() {
  this.waveform.pause();
}

<ng-waveform #waveform class="waveform"
    [src]="src"
    [height]="150"
    [useRegion]="true"
    backgroundColor="#d3d3d3"
    regionBackgroundColor="rgba(255, 255, 255, 0.7)"
    regionStartStickColor="#21f032"
    regionEndStickColor="red"
    regionTextColor="#09417e"
    [withRegionLabels]="true"
    waveColor="#ff11ff"
    (trackLoaded)="onTrackLoaded($event)"
    (rendered)="onTrackRendered($event)"
    (durationChange)="onDurationChange($event)"
    (timeUpdate)="onTimeUpdate($event)"
    (paused)="onPaused()"
    (regionChange)="onRegionChange($event)"
  >
</ng-waveform>

API Reference

NgWaveformComponent

Methods

• play(start: number = 0): void Play audio, start - starting position

• pause(): void Stops audio

Events

• trackLoaded - emits when data fetched from Url, returns time in ms spent for fetching.
• rendered - emits when waveform is rendered, returns time in ms spent for rendering.
• durationChange - emits when duration of audio is changed, returns duration value in seconds.
• timeUpdate - emits when current time of audio changes, returns object that implements interface ITimeUpdateEvent.
• paused - emits when audio paused. Useful for switch Play/Pause buttons in external control.
• regionChange - emits when region start or/and end positions change, returns object that implements interface IRegionPositions.

Properties

Name	Description
src: string	Url of src mp3 file
height = 100	Height of component
waveColor = '#d3d3d3'	Color of wave
backgroundColor = 'transparent'	Background color of component
overlayBackgroundColor = 'rgba(0, 0, 0, 0.5)'	Background color of overlay filling component while playing
useRegion: boolean	Turn region on
withRegionLabels: boolean	Turn region labels on
regionBackgroundColor = 'transparent'	Background color of region
regionStartStickColor = 'red'	Color of region left border stick
regionEndStickColor = 'red'	Color of region right border stick
regionTextColor = '#000'	Color of region labels text
autoplay	Turn autoplay on load on

Intrfaces

interface ITimeUpdateEvent {
  time: number;
  progress: number;
}

interface IRegionPositions {
  start: number;
  end: number;
}

Credits

Thank you very much for great inspiration wavesurfer.js team.

Conclusion

Feedback, issues and stars will be very appreciated.