view src/app/waveform/waveform.component.ts @ 157:3f54066a0e01

Prevent seeking when panning with mouse. There's still potential for this approach to go wrong, for both zooming and panning. During the duration of the click, if the offset or zoom are returned to the starting position, the mouse will seek to its current x position.

import {
  Component, OnInit, ViewChild, ElementRef, Input, AfterViewInit, NgZone,
  OnDestroy
} from '@angular/core';
import {AudioPlayerService} from "../services/audio-player/audio-player.service";
import wavesUI from 'waves-ui';
import {
  FeatureExtractionService
} from "../services/feature-extraction/feature-extraction.service";
import {Subscription} from "rxjs";
import {
  FeatureCollection,
  FixedSpacedFeatures, SimpleResponse
} from "piper/HigherLevelUtilities";
import {toSeconds} from "piper";
import {FeatureList, Feature} from "piper/Feature";
import * as Hammer from 'hammerjs';
import {WavesSpectrogramLayer} from "../spectrogram/Spectrogram";

type Timeline = any; // TODO what type actually is it.. start a .d.ts for waves-ui?
type Layer = any;
type Track = any;
type Colour = string;

@Component({
  selector: 'app-waveform',
  templateUrl: './waveform.component.html',
  styleUrls: ['./waveform.component.css']
})
export class WaveformComponent implements OnInit, AfterViewInit, OnDestroy {

  @ViewChild('track') trackDiv: ElementRef;

  private _audioBuffer: AudioBuffer;
  private timeline: Timeline;
  private cursorLayer: any;

  @Input()
  set audioBuffer(buffer: AudioBuffer) {
    this._audioBuffer = buffer || undefined;
    if (this.audioBuffer) {
      this.renderWaveform(this.audioBuffer);
      this.renderSpectrogram(this.audioBuffer);
    }
  }

  get audioBuffer(): AudioBuffer {
    return this._audioBuffer;
  }

  private featureExtractionSubscription: Subscription;
  private playingStateSubscription: Subscription;
  private seekedSubscription: Subscription;
  private isPlaying: boolean;
  private offsetAtPanStart: number;
  private initialZoom: number;
  private initialDistance: number;
  private zoomOnMouseDown: number;
  private offsetOnMouseDown: number;

  constructor(private audioService: AudioPlayerService,
              private piperService: FeatureExtractionService,
              public ngZone: NgZone) {
    this._audioBuffer = undefined;
    this.timeline = undefined;
    this.cursorLayer = undefined;
    this.isPlaying = false;
    const colours = function* () {
      const circularColours = [
        'black',
        'red',
        'green',
        'purple',
        'orange'
      ];
      let index = 0;
      const nColours = circularColours.length;
      while (true) {
        yield circularColours[index = ++index % nColours];
      }
    }();

    this.featureExtractionSubscription = piperService.featuresExtracted$.subscribe(
      features => {
        this.renderFeatures(features, colours.next().value);
      });
    this.playingStateSubscription = audioService.playingStateChange$.subscribe(
      isPlaying => {
        this.isPlaying = isPlaying;
        if (this.isPlaying)
          this.animate();
      });
    this.seekedSubscription = audioService.seeked$.subscribe(() => {
      if (!this.isPlaying)
        this.animate();
    });
  }

  ngOnInit() {
  }

  ngAfterViewInit(): void {
    this.timeline = this.renderTimeline();
  }

  renderTimeline(duration: number = 1.0): Timeline {
    const track: HTMLElement = this.trackDiv.nativeElement;
    track.innerHTML = "";
    const height: number = track.getBoundingClientRect().height;
    const width: number = track.getBoundingClientRect().width;
    const pixelsPerSecond = width / duration;
    const timeline = new wavesUI.core.Timeline(pixelsPerSecond, width);
    timeline.createTrack(track, height/2, 'wave');
    timeline.createTrack(track, height/2, 'grid');
    return timeline;
  }

  estimatePercentile(matrix, percentile) {
    // our sample is not evenly distributed across the whole data set:
    // it is guaranteed to include at least one sample from every
    // column, and could sample some values more than once. But it
    // should be good enough in most cases (todo: show this)
    if (matrix.length === 0) {
      return 0.0;
    }
    const w = matrix.length;
    const h = matrix[0].length;
    const n = w * h;
    const m = (n > 50000 ? 50000 : n); // should base that on the %ile
    let m_per = Math.floor(m / w);
    if (m_per < 1) m_per = 1;
    let sample = [];
    for (let x = 0; x < w; ++x) {
      for (let i = 0; i < m_per; ++i) {
        const y = Math.floor(Math.random() * h);
        const value = matrix[x][y];
        if (!isNaN(value) && value !== Infinity) {
          sample.push(value);
        }
      }
    }
    if (sample.length === 0) {
      console.log("WARNING: No samples gathered, even though we hoped for " +
                  (m_per * w) + " of them");
      return 0.0;
    }
    sample.sort((a,b) => { return a - b; });
    const ix = Math.floor((sample.length * percentile) / 100);
    console.log("Estimating " + percentile + "-%ile of " +
                n + "-sample dataset (" + w + " x " + h + ") as value " + ix +
                " of sorted " + sample.length + "-sample subset");
    const estimate = sample[ix];
    console.log("Estimate is: " + estimate + " (where min sampled value = " +
                sample[0] + " and max = " + sample[sample.length-1] + ")");
    return estimate;
  }

  interpolatingMapper(hexColours) {
    const colours = hexColours.map(n => {
      const i = parseInt(n, 16);
      return [ ((i >> 16) & 255) / 255.0,
               ((i >> 8) & 255) / 255.0,
               ((i) & 255) / 255.0 ];
    });
    const last = colours.length - 1;
    return (value => {
      const m = value * last;
      if (m >= last) {
        return colours[last];
      }
      if (m <= 0) {
        return colours[0];
      }
      const base = Math.floor(m);
      const prop0 = base + 1.0 - m;
      const prop1 = m - base;
      const c0 = colours[base];
      const c1 = colours[base+1];
      return [ c0[0] * prop0 + c1[0] * prop1,
               c0[1] * prop0 + c1[1] * prop1,
               c0[2] * prop0 + c1[2] * prop1 ];
    });
  }

  iceMapper() {
    let hexColours = [
      // Based on ColorBrewer ylGnBu
      "ffffff", "ffff00", "f7fcf0", "e0f3db", "ccebc5", "a8ddb5",
      "7bccc4", "4eb3d3", "2b8cbe", "0868ac", "084081", "042040"
    ];
    hexColours.reverse();
    return this.interpolatingMapper(hexColours);
  }

  hsv2rgb(h, s, v) { // all values in range [0, 1]
    const i = Math.floor(h * 6);
    const f = h * 6 - i;
    const p = v * (1 - s);
    const q = v * (1 - f * s);
    const t = v * (1 - (1 - f) * s);
    let r = 0, g = 0, b = 0;
    switch (i % 6) {
        case 0: r = v, g = t, b = p; break;
        case 1: r = q, g = v, b = p; break;
        case 2: r = p, g = v, b = t; break;
        case 3: r = p, g = q, b = v; break;
        case 4: r = t, g = p, b = v; break;
        case 5: r = v, g = p, b = q; break;
    }
    return [ r, g, b ];
  }

  greenMapper() {
    const blue = 0.6666;
    const pieslice = 0.3333;
    return (value => {
      const h = blue - value * 2.0 * pieslice;
      const s = 0.5 + value / 2.0;
      const v = value;
      return this.hsv2rgb(h, s, v);
    });
  }

  sunsetMapper() {
    return (value => {
      let r = (value - 0.24) * 2.38;
      let g = (value - 0.64) * 2.777;
      let b = (3.6 * value);
      if (value > 0.277) b = 2.0 - b;
      return [ r, g, b ];
    });
  }

  clearTimeline(): void {
    // loop through layers and remove them, waves-ui provides methods for this but it seems to not work properly
    const timeContextChildren = this.timeline.timeContext._children;
    for (let track of this.timeline.tracks) {
      if (track.layers.length === 0) { continue; }
      const trackLayers = Array.from(track.layers);
      while (trackLayers.length) {
        let layer: Layer = trackLayers.pop();
        track.remove(layer);

        const index = timeContextChildren.indexOf(layer.timeContext);
        if (index >= 0) {
          timeContextChildren.splice(index, 1);
        }
        layer.destroy();
      }
    }
  }

  renderWaveform(buffer: AudioBuffer): void {
    const height: number = this.trackDiv.nativeElement.getBoundingClientRect().height / 2;
    const waveTrack = this.timeline.getTrackById('wave');
    if (this.timeline) {
      // resize
      const width = this.trackDiv.nativeElement.getBoundingClientRect().width;

      this.clearTimeline();

      this.timeline.visibleWidth = width;
      this.timeline.pixelsPerSecond = width / buffer.duration;
      waveTrack.height = height;
    } else {
      this.timeline = this.renderTimeline(buffer.duration)
    }
    this.timeline.timeContext.offset = 0.5 * this.timeline.timeContext.visibleDuration;

    // time axis
    const timeAxis = new wavesUI.helpers.TimeAxisLayer({
      height: height,
      color: '#b0b0b0'
    });
    this.addLayer(timeAxis, waveTrack, this.timeline.timeContext, true);

    const waveformLayer = new wavesUI.helpers.WaveformLayer(buffer, {
      top: 10,
      height: height * 0.9,
      color: 'darkblue'
    });
    this.addLayer(waveformLayer, waveTrack, this.timeline.timeContext);

    this.cursorLayer = new wavesUI.helpers.CursorLayer({
      height: height
    });
    this.addLayer(this.cursorLayer, waveTrack, this.timeline.timeContext);
    this.timeline.state = new wavesUI.states.CenteredZoomState(this.timeline);
    waveTrack.render();
    waveTrack.update();


    if ('ontouchstart' in window) {
      interface Point {
        x: number;
        y: number;
      }

      let zoomGestureJustEnded: boolean = false;

      const pixelToExponent: Function = wavesUI.utils.scales.linear()
        .domain([0, 100]) // 100px => factor 2
        .range([0, 1]);

      const calculateDistance: (p1: Point, p2: Point) => number = (p1, p2) => {
        return Math.pow(
          Math.pow(p2.x - p1.x, 2) +
          Math.pow(p2.y - p1.y, 2), 0.5);
      };

      const hammertime = new Hammer(this.trackDiv.nativeElement);
      const scroll = (ev) => {
        if (zoomGestureJustEnded) {
          zoomGestureJustEnded = false;
          console.log("Skip this event: likely a single touch dangling from pinch");
          return;
        }
        this.timeline.timeContext.offset = this.offsetAtPanStart +
          this.timeline.timeContext.timeToPixel.invert(ev.deltaX);
        this.timeline.tracks.update();
      };

      const zoom = (ev) => {
        const minZoom = this.timeline.state.minZoom;
        const maxZoom = this.timeline.state.maxZoom;
        const distance = calculateDistance({
          x: ev.pointers[0].clientX,
          y: ev.pointers[0].clientY
        }, {
          x: ev.pointers[1].clientX,
          y: ev.pointers[1].clientY
        });

        const lastCenterTime =
          this.timeline.timeContext.timeToPixel.invert(ev.center.x);

        const exponent = pixelToExponent(distance - this.initialDistance);
        const targetZoom = this.initialZoom * Math.pow(2, exponent);

        this.timeline.timeContext.zoom =
          Math.min(Math.max(targetZoom, minZoom), maxZoom);

        const newCenterTime =
          this.timeline.timeContext.timeToPixel.invert(ev.center.x);

        this.timeline.timeContext.offset += newCenterTime - lastCenterTime;
        this.timeline.tracks.update();
      };
      hammertime.get('pinch').set({ enable: true });
      hammertime.on('panstart', () => {
        this.offsetAtPanStart = this.timeline.timeContext.offset;
      });
      hammertime.on('panleft', scroll);
      hammertime.on('panright', scroll);
      hammertime.on('pinchstart', (e) => {
        this.initialZoom = this.timeline.timeContext.zoom;

        this.initialDistance = calculateDistance({
          x: e.pointers[0].clientX,
          y: e.pointers[0].clientY
        }, {
          x: e.pointers[1].clientX,
          y: e.pointers[1].clientY
        });
      });
      hammertime.on('pinch', zoom);
      hammertime.on('pinchend', () => {
        zoomGestureJustEnded = true;
      });
    }

    this.animate();
  }

  renderSpectrogram(buffer: AudioBuffer): void {
    const height: number = this.trackDiv.nativeElement.getBoundingClientRect().height / 2;
    const gridTrack = this.timeline.getTrackById('grid');

    const spectrogramLayer = new WavesSpectrogramLayer(buffer, {
      top: height * 0.05,
      height: height * 0.9,
      stepSize: 512,
      blockSize: 1024,
      normalise: 'none',
      mapper: this.sunsetMapper()
    });
    this.addLayer(spectrogramLayer, gridTrack, this.timeline.timeContext);

    this.timeline.tracks.update();
  }

  // TODO refactor - this doesn't belong here
  private renderFeatures(extracted: SimpleResponse, colour: Colour): void {
    if (!extracted.hasOwnProperty('features') || !extracted.hasOwnProperty('outputDescriptor')) return;
    if (!extracted.features.hasOwnProperty('shape') || !extracted.features.hasOwnProperty('data')) return;
    const features: FeatureCollection = (extracted.features as FeatureCollection);
    const outputDescriptor = extracted.outputDescriptor;
    const height = this.trackDiv.nativeElement.getBoundingClientRect().height / 2;
    const waveTrack = this.timeline.getTrackById('wave');

    // TODO refactor all of this
    switch (features.shape) {
      case 'vector': {
        const stepDuration = (features as FixedSpacedFeatures).stepDuration;
        const featureData = (features.data as Float32Array);
        if (featureData.length === 0) return;
        const normalisationFactor = 1.0 /
          featureData.reduce(
            (currentMax, feature) => Math.max(currentMax, feature),
            -Infinity
          );

        const plotData = [...featureData].map((feature, i) => {
          return {
            cx: i * stepDuration,
            cy: feature * normalisationFactor
          };
        });

        let lineLayer = new wavesUI.helpers.LineLayer(plotData, {
          color: colour,
          height: height
        });
        this.addLayer(
          lineLayer,
          waveTrack,
          this.timeline.timeContext
        );
        break;
      }
      case 'list': {
        const featureData = (features.data as FeatureList);
        if (featureData.length === 0) return;
        // TODO look at output descriptor instead of directly inspecting features
        const hasDuration = outputDescriptor.configured.hasDuration;
        const isMarker = !hasDuration
          && outputDescriptor.configured.binCount === 0
          && featureData[0].featureValues == null;
        const isRegion = hasDuration
          && featureData[0].timestamp != null;
        console.log("Have list features: length " + featureData.length +
                    ", isMarker " + isMarker + ", isRegion " + isRegion +
                    ", hasDuration " + hasDuration);
        // TODO refactor, this is incomprehensible
        if (isMarker) {
          const plotData = featureData.map(feature => {
            return {time: toSeconds(feature.timestamp)}
          });
          let featureLayer = new wavesUI.helpers.TickLayer(plotData, {
            height: height,
            color: colour,
          });
          this.addLayer(
            featureLayer,
            waveTrack,
            this.timeline.timeContext
          );
        } else if (isRegion) {
          console.log("Output is of region type");
          const binCount = outputDescriptor.configured.binCount || 0;
          const isBarRegion = featureData[0].featureValues.length >= 1 || binCount >= 1 ;
          const getSegmentArgs = () => {
            if (isBarRegion) {

              // TODO refactor - this is messy
              interface FoldsToNumber<T> {
                reduce(fn: (previousValue: number,
                            currentValue: T,
                            currentIndex: number,
                            array: ArrayLike<T>) => number,
                       initialValue?: number): number;
              }

              // TODO potentially change impl., i.e avoid reduce
              const findMin = <T>(arr: FoldsToNumber<T>, getElement: (x: T) => number): number => {
                return arr.reduce((min, val) => Math.min(min, getElement(val)), Infinity);
              };

              const findMax = <T>(arr: FoldsToNumber<T>, getElement: (x: T) => number): number => {
                return arr.reduce((min, val) => Math.max(min, getElement(val)), -Infinity);
              };

              const min = findMin<Feature>(featureData, (x: Feature) => {
                return findMin<number>(x.featureValues, y => y);
              });

              const max = findMax<Feature>(featureData, (x: Feature) => {
                return findMax<number>(x.featureValues, y => y);
              });

              const barHeight = 1.0 / height;
              return [
                featureData.reduce((bars, feature) => {
                  const staticProperties = {
                    x: toSeconds(feature.timestamp),
                    width: toSeconds(feature.duration),
                    height: min + barHeight,
                    color: colour,
                    opacity: 0.8
                  };
                  // TODO avoid copying Float32Array to an array - map is problematic here
                  return bars.concat([...feature.featureValues]
                    .map(val => Object.assign({}, staticProperties, {y: val})))
                }, []),
                {yDomain: [min, max + barHeight], height: height} as any
              ];
            } else {
              return [featureData.map(feature => {
                return {
                  x: toSeconds(feature.timestamp),
                  width: toSeconds(feature.duration),
                  color: colour,
                  opacity: 0.8
                }
              }), {height: height}];
            }
          };

          let segmentLayer = new wavesUI.helpers.SegmentLayer(
            ...getSegmentArgs()
          );
          this.addLayer(
            segmentLayer,
            waveTrack,
            this.timeline.timeContext
          );
        }
        break;
      }
      case 'matrix': {
        const stepDuration = (features as FixedSpacedFeatures).stepDuration;
        //!!! + start time
        const matrixData = (features.data as Float32Array[]);
        if (matrixData.length === 0) return;
        console.log("matrix data length = " + matrixData.length);
        console.log("height of first column = " + matrixData[0].length);
        const targetValue = this.estimatePercentile(matrixData, 95);
        const gain = (targetValue > 0.0 ? (1.0 / targetValue) : 1.0);
        console.log("setting gain to " + gain);
        const matrixEntity =
          new wavesUI.utils.PrefilledMatrixEntity(matrixData,
                                                  0, // startTime
                                                  stepDuration);
        let matrixLayer = new wavesUI.helpers.MatrixLayer(matrixEntity, {
          gain,
          height: height * 0.9,
          top: height * 0.05,
          normalise: 'none',
          mapper: this.iceMapper()
        });
        this.addLayer(
          matrixLayer,
          waveTrack,
          this.timeline.timeContext
        );
        break;
      }
      default:
        console.log("Cannot render an appropriate layer for feature shape '" +
                    features.shape + "'");
    }

    this.timeline.tracks.update();
  }

  private animate(): void {
    this.ngZone.runOutsideAngular(() => {
      // listen for time passing...
      const updateSeekingCursor = () => {
        const currentTime = this.audioService.getCurrentTime();
        this.cursorLayer.currentPosition = currentTime;
        this.cursorLayer.update();

        const currentOffset = this.timeline.timeContext.offset;
        const offsetTimestamp = currentOffset
          + currentTime;

        const visibleDuration = this.timeline.timeContext.visibleDuration;
        // TODO reduce duplication between directions and make more declarative
        // this kinda logic should also be tested
        const mustPageForward = offsetTimestamp > visibleDuration;
        const mustPageBackward = currentTime < -currentOffset;

        if (mustPageForward) {
          const hasSkippedMultiplePages = offsetTimestamp - visibleDuration > visibleDuration;

            this.timeline.timeContext.offset = hasSkippedMultiplePages ?
                -currentTime +  0.5 * visibleDuration :
                currentOffset - visibleDuration;
          this.timeline.tracks.update();
        }

        if (mustPageBackward) {
          const hasSkippedMultiplePages = currentTime + visibleDuration < -currentOffset;
            this.timeline.timeContext.offset = hasSkippedMultiplePages ?
                -currentTime + 0.5 * visibleDuration :
                currentOffset + visibleDuration;
          this.timeline.tracks.update();
        }

        if (this.isPlaying)
          requestAnimationFrame(updateSeekingCursor);
      };
      updateSeekingCursor();
    });
  }

  private addLayer(layer: Layer, track: Track, timeContext: any, isAxis: boolean = false): void {
    timeContext.zoom = 1.0;
    if (!layer.timeContext) {
      layer.setTimeContext(isAxis ?
        timeContext : new wavesUI.core.LayerTimeContext(timeContext));
    }
    track.add(layer);
    layer.render();
    layer.update();
    if (this.cursorLayer && track.$layout.contains(this.cursorLayer.$el)) {
      track.$layout.appendChild(this.cursorLayer.$el);
    }
  }

  private static changeColour(layer: Layer, colour: string): void {
    const butcherShapes = (shape) => {
      shape.install({color: () => colour});
      shape.params.color = colour;
      shape.update(layer._renderingContext, layer.data);
    };

    layer._$itemCommonShapeMap.forEach(butcherShapes);
    layer._$itemShapeMap.forEach(butcherShapes);
    layer.render();
    layer.update();
  }

  ngOnDestroy(): void {
    this.featureExtractionSubscription.unsubscribe();
    this.playingStateSubscription.unsubscribe();
    this.seekedSubscription.unsubscribe();
  }

  seekStart(): void {
    this.zoomOnMouseDown = this.timeline.timeContext.zoom;
    this.offsetOnMouseDown = this.timeline.timeContext.offset;
  }

  seekEnd(x: number): void {
    const hasSameZoom: boolean = this.zoomOnMouseDown ===
      this.timeline.timeContext.zoom;
    const hasSameOffset: boolean = this.offsetOnMouseDown ===
      this.timeline.timeContext.offset;
    if (hasSameZoom && hasSameOffset) {
      this.seek(x);
    }
  }

  seek(x: number): void {
    if (this.timeline) {
      const timeContext: any = this.timeline.timeContext;
      this.audioService.seekTo(
        timeContext.timeToPixel.invert(x)- timeContext.offset
      );
    }
  }
}