blocktrail / blocktrail-sdk-nodejs

				/*

				 * processes 16 bit RGBA and grayscale + alpha images

				 */

				if(img.bits === 16) {

					var pixels = new Uint32Array(img.decodePixels().buffer),

						len = pixels.length,

						imgData = new Uint8Array((len * (32 / img.pixelBitlength) ) * img.colors),

						alphaData = new Uint8Array(len * (32 / img.pixelBitlength) ),

						hasColors = img.colors > 1,

						i = 0, n = 0, a = 0, pixel;

					while(i < len) {

						pixel = pixels[i++];

						imgData[n++] = (pixel >>> 0) & 0xFF;

						if(hasColors) {

							imgData[n++] = (pixel >>> 16) & 0xFF;

							pixel = pixels[i++];

							imgData[n++] = (pixel >>> 0) & 0xFF;

						}

						alphaData[a++] = (pixel >>> 16) & 0xFF;

					}

					bpc = 8;

				}

				if(canCompress(compression)) {

				/*

				 * processes 8 bit RGBA and grayscale + alpha images

				 */

				if(img.bits === 8) {

					var pixelsArrayType = window['Uint' + img.pixelBitlength + 'Array'],

						pixels = new pixelsArrayType(img.decodePixels().buffer),

						len = pixels.length,

						imgData = new Uint8Array(len * img.colors),

						alphaData = new Uint8Array(len),

						pDiff = img.pixelBitlength - img.bits,

						i = 0, n = 0, pixel, pbl;

					for(; i < len; i++) {

						pixel = pixels[i];

						pbl = 0;

						while(pbl < pDiff) {

							imgData[n++] = ( pixel >>> pbl ) & 0xff;

							pbl = pbl + img.bits;

						}

						alphaData[i] = ( pixel >>> pbl ) & 0xff;

					}

				}

				/*

				 * processes 16 bit RGBA and grayscale + alpha images