Add matrix math module (#358)

* Add matrix math module

* add info.json file

* correct format of module

* Add a constant factor input field

* clone the pixels array

* change default values

src/modules/Convolution/Convolution.js

@@ -0,0 +1,71 @@
+var _ = require('lodash');
+module.exports = exports = function(pixels, constantFactor, kernelValues){
+	let kernel = kernelGenerator(constantFactor, kernelValues), oldpix = _.cloneDeep(pixels);
+	kernel = flipKernel(kernel);
+
+	for (let i = 0; i < pixels.shape[0]; i++) {
+        for (let j = 0; j < pixels.shape[1]; j++) {
+            let neighboutPos = getNeighbouringPixelPositions([i, j]);
+            let acc = [0.0, 0.0, 0.0, 0.0];
+            for (let a = 0; a < kernel.length; a++) {
+                for (let b = 0; b < kernel.length; b++) {
+                    acc[0] += (oldpix.get(neighboutPos[a][b][0], neighboutPos[a][b][1], 0) * kernel[a][b]);
+                    acc[1] += (oldpix.get(neighboutPos[a][b][0], neighboutPos[a][b][1], 1) * kernel[a][b]);
+                    acc[2] += (oldpix.get(neighboutPos[a][b][0], neighboutPos[a][b][1], 2) * kernel[a][b]);
+                    acc[3] += (oldpix.get(neighboutPos[a][b][0], neighboutPos[a][b][1], 3) * kernel[a][b]);
+                }
+            }
+            acc[0] = acc[0]%255;
+            acc[1] = acc[1]%255;
+            acc[2] = acc[2]%255;
+            pixels.set(i, j, 0, acc[0]);
+            pixels.set(i, j, 1, acc[1]);
+            pixels.set(i, j, 2, acc[2]);
+        }
+    }
+    return pixels;
+
+
+	function kernelGenerator(constantFactor, kernelValues){
+		kernelValues = kernelValues.split(" ");
+        for(i = 0 ; i < 9; i++){
+            kernelValues[i] = Number(kernelValues[i]) * constantFactor;
+        }
+        let k = 0;
+		let arr = [];
+		for(i = 0; i < 3; i++){
+			let columns = [];
+			for(j = 0; j < 3; j++){
+				columns.push(kernelValues[k]);
+				k += 1;
+			}
+			arr.push(columns);
+		}
+		return arr;
+	}
+
+	function getNeighbouringPixelPositions(pixelPosition) {
+        let x = pixelPosition[0], y = pixelPosition[1], result = [];
+
+        for (let i = -1; i <= 1; i++) {
+            let arr = [];
+            for (let j = -1; j <= 1; j++)
+                arr.push([x + i, y + j]);
+
+            result.push(arr);
+        }
+        return result;
+    }
+
+	function flipKernel(kernel) {
+        let result = [];
+        for (let i = kernel.length - 1; i >= 0; i--) {
+            let arr = [];
+            for (let j = kernel[i].length - 1; j >= 0; j--) {
+                arr.push(kernel[i][j]);
+            }
+            result.push(arr);
+        }
+        return result;
+    }
+}