Sha256: c6f45d7001b43327993ec961cc99937fbf0303df40f62751aabf8a92c85922bd
Contents?: true
Size: 1.41 KB
Versions: 7
Compression:
Stored size: 1.41 KB
Contents
/*global define*/
define(function() {
"use strict";
var context2DsByWidthAndHeight = {};
/**
* Extract a pixel array from a loaded image. Draws the image
* into a canvas so it can read the pixels back.
*
* @exports getImagePixels
*
* @param {Image} image The image to extract pixels from.
*
* @returns {CanvasPixelArray} The pixels of the image.
*/
var getImagePixels = function(image, width, height) {
if (typeof width === 'undefined') {
width = image.width;
}
if (typeof height === 'undefined') {
height = image.height;
}
var context2DsByHeight = context2DsByWidthAndHeight[width];
if (typeof context2DsByHeight === 'undefined') {
context2DsByHeight = {};
context2DsByWidthAndHeight[width] = context2DsByHeight;
}
var context2d = context2DsByHeight[height];
if (typeof context2d === 'undefined') {
var canvas = document.createElement('canvas');
canvas.width = width;
canvas.height = height;
context2d = canvas.getContext('2d');
context2d.globalCompositeOperation = 'copy';
context2DsByHeight[height] = context2d;
}
context2d.drawImage(image, 0, 0, width, height);
return context2d.getImageData(0, 0, width, height).data;
};
return getImagePixels;
});
Version data entries
7 entries across 7 versions & 1 rubygems