Add alpha to analysis result.

demoassets/main.js

@@ -44,6 +44,7 @@ $(function(){
 			$('#red').css('width',data.red+'%');
 			$('#green').css('width',data.green+'%');
 			$('#blue').css('width',data.blue+'%');
+			$('#alpha').css('width',data.alpha+'%');
 			$('#brightness').css('width',data.brightness+'%');
 		});
 

index.html

@@ -39,7 +39,7 @@
 									</p>
 									<div id="image-data" style="display:none">
 
-										RGB
+										RGBA
 									    <div class="progress progress-danger">
 										    <div id="red" class="bar" style="width: 0%;"></div>
 									    </div>
@@ -49,6 +49,9 @@
 									    <div class="progress">
 										    <div id="blue" class="bar" style="width: 0%;"></div>
 									    </div>
+									    <div class="progress">
+										    <div id="alpha" class="bar" style="width: 0%;"></div>
+									    </div>
 
 									    Brightness
 									    <div class="progress progress-warning">

resemble.js

@@ -116,6 +116,7 @@ URL: https://github.com/Huddle/Resemble.js
 			var redTotal = 0;
 			var greenTotal = 0;
 			var blueTotal = 0;
+			var alphaTotal = 0;
 			var brightnessTotal = 0;
 
 			loop(height, width, function(verticalPos, horizontalPos){
@@ -123,6 +124,7 @@ URL: https://github.com/Huddle/Resemble.js
 				var red = sourceImageData[offset];
 				var green = sourceImageData[offset + 1];
 				var blue = sourceImageData[offset + 2];
+				var alpha = sourceImageData[offset + 3];
 				var brightness = getBrightness(red,green,blue);
 
 				pixelCount++;
@@ -130,12 +132,14 @@ URL: https://github.com/Huddle/Resemble.js
 				redTotal += red / 255 * 100;
 				greenTotal += green / 255 * 100;
 				blueTotal += blue / 255 * 100;
+				alphaTotal += (255 - alpha) / 255 * 100;
 				brightnessTotal += brightness / 255 * 100;
 			});
 
 			data.red = Math.floor(redTotal / pixelCount);
 			data.green = Math.floor(greenTotal / pixelCount);
 			data.blue = Math.floor(blueTotal / pixelCount);
+			data.alpha = Math.floor(alphaTotal / pixelCount);
 			data.brightness = Math.floor(brightnessTotal / pixelCount);
 
 			triggerDataUpdate();