image-js/lib/image/filter/hypotenuse.js

Image processing and manipulation in JavaScript

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = hypotenuse;
var _channel = require("../../util/channel");
var _Image = _interopRequireDefault(require("../Image"));
function _interopRequireDefault(e) { return e && e.__esModule ? e : { default: e }; }
/**
 * Calculate a new image that is the hypotenuse between the current image and the otherImage.
 * @memberof Image
 * @instance
 * @param {Image} otherImage
 * @param {object} [options={}]
 * @param {number} [options.bitDepth=this.bitDepth]
 * @param {number[]|string[]} [options.channels] : to which channel to apply the filter. By default all but alpha.
 * @return {Image}
 */
function hypotenuse(otherImage, options = {}) {
  let {
    bitDepth = this.bitDepth,
    channels
  } = options;
  this.checkProcessable('hypotenuse', {
    bitDepth: [8, 16, 32]
  });
  if (this.width !== otherImage.width || this.height !== otherImage.height) {
    throw new Error('hypotenuse: both images must have the same size');
  }
  if (this.alpha !== otherImage.alpha || this.bitDepth !== otherImage.bitDepth) {
    throw new Error('hypotenuse: both images must have the same alpha and bitDepth');
  }
  if (this.channels !== otherImage.channels) {
    throw new Error('hypotenuse: both images must have the same number of channels');
  }
  let newImage = _Image.default.createFrom(this, {
    bitDepth: bitDepth
  });
  channels = (0, _channel.validateArrayOfChannels)(this, {
    channels: channels
  });
  let clamped = newImage.isClamped;
  for (let j = 0; j < channels.length; j++) {
    let c = channels[j];
    for (let i = c; i < this.data.length; i += this.channels) {
      let value = Math.hypot(this.data[i], otherImage.data[i]);
      if (clamped) {
        // we calculate the clamped result
        newImage.data[i] = Math.min(Math.max(Math.round(value), 0), newImage.maxValue);
      } else {
        newImage.data[i] = value;
      }
    }
  }
  return newImage;
}