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import { Color } from "../deps/color.ts";
/** * Histogram of colors with reduced space * Effectively quantizes the image into 32768 colors */export class ColorHistogram {  #data: Uint32Array;  constructor() {    this.#data = new Uint32Array(32768);  }  #getIndex(color: Color) {    // ignore alpha    const index = ((color.r >> 3) << (10)) + ((color.g >> 3) << 5) +      (color.b >> 3);    return index;  }  get(color: Color): number {    const index = this.#getIndex(color);    return this.#data[index];  }  getQuantized(color: [number, number, number]): number {    const index = (color[0] << 10) + (color[1] << 5) + color[2];    return this.#data[index];  }  add(color: Color, amount: number): number {    const index = this.#getIndex(color);    return Atomics.add(this.#data, index, amount);  }  get raw(): Uint32Array {    return this.#data;  }  get length(): number {    return this.#data.filter((x) => x).length;  }  static getColor(index: number): Color {    const ri = index >> 10;    const gi = (index - (ri << 10)) >> 5;    const bi = (index - (ri << 10) - (gi << 5));    return new Color(ri << 3, gi << 3, bi << 3, 255);  }}
/** Get a histogram of frequency of colors. */export function getHistogram(colors: Color[]): ColorHistogram {  const histo = new ColorHistogram();  let i = 0;  while (i < colors.length) {    const hIndex = colors[i];    histo.add(hIndex, 1);    i += 1;  }  return histo;}