voluptasquisquam/src/image/filter/sobelFilter.js

Image processing and manipulation in JavaScript

import convolution from '../operator/convolution';
import {GRADIENT_X, GRADIENT_Y} from '../../util/kernels';

/**
 * @memberof Image
 * @instance
 * @param {object} [options]
 * @param {Array<Array<number>>} [options.kernelX]
 * @param {Array<Array<number>>} [options.kernelY]
 * @param {string} [options.border='copy']
 * @param {*} [options.channels]
 * #param {number} [options.bitDepth=this.bitDepth] Specify the bitDepth of the resulting image
 * @return {Image}
 */
export default function sobelFilter(options = {}) {
    let {
        kernelX = GRADIENT_X,
        kernelY = GRADIENT_Y,
        border = 'copy',
        channels,
        bitDepth = this.bitDepth
    } = options;

    this.checkProcessable('sobel', {
        bitDepth: [8, 16]
    });

    let gX = convolution.call(this, kernelX, {
        channels: channels,
        border: border,
        bitDepth: 32
    });

    let gY = convolution.call(this, kernelY, {
        channels: channels,
        border: border,
        bitDepth: 32
    });

    return gX.hypotenuse(gY, {bitDepth, channels: channels});
}