Initial Commit

node_modules/color-space/ycgco.js

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+/**
+ * https://en.wikipedia.org/?title=YCgCo
+ *
+ * @module  color-space/ycgco
+ */
+import rgb from './rgb.js';
+
+
+var ycgco = {
+	name: 'ycgco',
+	min: [0, -0.5, -0.5],
+	max: [1, 0.5, 0.5],
+	channel: ['Y', 'Cg', 'Co'],
+	alias: ['YCgCo']
+};
+
+
+/**
+ * YCgCo to RGB
+ * transform through analog form
+ *
+ * @param {Array<number>} arr RGB values
+ *
+ * @return {Array<number>} YCgCo values
+ */
+ycgco.rgb = function (arr) {
+	var y = arr[0], cg = arr[1], co = arr[2];
+
+	var tmp = y - cg;
+
+	return [
+		(tmp + co) * 255,
+		(y + cg) * 255,
+		(tmp - co) * 255
+	];
+};
+
+
+/**
+ * RGB to YCgCo
+ * transform through analog form
+ *
+ * @param {Array<number>} arr YCgCo values
+ *
+ * @return {Array<number>} RGB values
+ */
+rgb.ycgco = function (arr) {
+	var r = arr[0] / 255, g = arr[1] / 255, b = arr[2] / 255;
+
+	return [
+		0.25 * r + 0.5 * g + 0.25 * b,
+		-0.25 * r + 0.5 * g - 0.25 * b,
+		0.5 * r - 0.5 * b
+	];
+};
+
+
+export default (ycgco);