start to average module (#249)

* start to average module

* completed average module

* added average module, version bump

src/modules/Average/Module.js

@@ -0,0 +1,86 @@
+/*
+* Average all pixel colors
+*/
+module.exports = function Average(options, UI){
+    options = options || {};
+    options.blur = options.blur || 2
+    
+    //Tell the UI that a step has been set up
+    UI.onSetup(options.step);
+    var output;
+
+    options.step.metadata = options.step.metadata || {};
+    
+    function draw(input,callback,progressObj){
+
+        progressObj.stop(true);
+        progressObj.overrideFlag = true;
+        
+        // Tell the UI that a step is being drawn
+        UI.onDraw(options.step);
+        
+        var step = this;
+        
+        function changePixel(r, g, b, a){
+            return [r,g,b,a]
+        }
+
+        // do the averaging        
+        function extraManipulation(pixels){
+            var sum = [0,0,0,0];
+            for (var i = 0; i < pixels.data.length; i += 4) {
+              sum[0] += pixels.data[i + 0];
+              sum[1] += pixels.data[i + 1];
+              sum[2] += pixels.data[i + 2];
+              sum[3] += pixels.data[i + 3];
+            }
+
+            sum[0] = parseInt(sum[0] / (pixels.data.length / 4));
+            sum[1] = parseInt(sum[1] / (pixels.data.length / 4));
+            sum[2] = parseInt(sum[2] / (pixels.data.length / 4));
+            sum[3] = parseInt(sum[3] / (pixels.data.length / 4));
+
+            for (var i = 0; i < pixels.data.length; i += 4) {
+              pixels.data[i + 0] = sum[0];
+              pixels.data[i + 1] = sum[1];
+              pixels.data[i + 2] = sum[2];
+              pixels.data[i + 3] = sum[3];
+            }
+            // report back and store average in metadata:
+            options.step.metadata.averages = sum;
+            console.log("average: ", sum);
+            return pixels;
+        }
+
+        function output(image, datauri, mimetype){
+            
+            // This output is accessible by Image Sequencer
+            step.output = {
+              src: datauri,
+              format: mimetype
+            };
+            
+            // This output is accessible by UI
+            options.step.output = datauri;
+            
+            // Tell UI that step has been drawn.
+            UI.onComplete(options.step);
+        }
+        
+        return require('../_nomodule/PixelManipulation.js')(input, {
+            output: output,
+            changePixel: changePixel,
+            extraManipulation: extraManipulation,
+            format: input.format,
+            image: options.image,
+            callback: callback
+        });
+        
+    }
+    return {
+        options: options,
+        draw:  draw,
+        output: output,
+        UI: UI
+    }
+}