view src/app/spectrogram/ColourMap.ts @ 456:7bb0bac6f8dc

Add export button for recordings and option to remove audio item (also removes all related analyses atm). Revokes associated object url for audio on removal. Will be problematic if the history is used for undo / redo.

/**
 * Created by lucast on 23/05/2017.
 */

export function 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 ];
  });
}

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

export function 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);
  });
}

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

export function 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 ];
}