analyzePixels = function analyzePixels() {

		var len = pixels.length;
		var nPix = len / 3;
		indexedPixels = [];
		var nq = new NeuQuant(pixels, len, sample);

		// initialize quantizer
		colorTab = nq.process(); // create reduced palette

		// map image pixels to new palette
		var k = 0;
		for (var j = 0; j < nPix; j++) {
			var index = nq.map(pixels[k++] & 0xff, pixels[k++] & 0xff, pixels[k++] & 0xff);
			usedEntry[index] = true;
			indexedPixels[j] = index;
		}

		pixels = null;
		colorDepth = 8;
		palSize = 7;

		// get closest match to transparent color if specified
		if (transparent !== null) {
			transIndex = findClosest(transparent);
		}
	}
Analyzes image colors and creates color map.