added dither files

DirectPrint/dither.cpp

@@ -0,0 +1,76 @@
+#include "dither.h"
+
+using namespace std;
+using namespace cv;
+
+uint8_t saturated_add(uint8_t val1, int8_t val2);
+
+Mat dither_image(Mat rawImg){
+    Mat dithImg;
+    int imgWidth;
+    int imgHeight;
+    
+    //Load the image and convert to grayscale first
+    cvtColor(rawImg, dithImg, CV_BGR2GRAY);
+
+
+    //Get the size info
+    imgWidth = dithImg.cols;
+    imgHeight = dithImg.rows;
+
+    //Run the 'Floyd-Steinberg' dithering algorithm
+  	int err;
+  	int8_t a,b,c,d;
+  
+  	for(int i=0; i<imgHeight; i++)
+  	{      
+    	for(int j=0; j<imgWidth; j++)
+    	{
+      		if(dithImg.at<uint8_t>(i,j) > 127)
+      		{
+        		err = dithImg.at<uint8_t>(i,j) - 255;
+        		dithImg.at<uint8_t>(i,j) = 255;
+      		}
+      		else
+      		{
+        		err = dithImg.at<uint8_t>(i,j) - 0;
+        		dithImg.at<uint8_t>(i,j) = 0;
+      		}
+
+      		a = (err * 7) / 16;
+      		b = (err * 1) / 16;
+      		c = (err * 5) / 16;
+      		d = (err * 3) / 16;
+      
+      		if((i != (imgHeight-1)) && (j != 0) && (j != (imgWidth - 1)))
+      		{
+        		dithImg.at<uint8_t>(i+0,j+1) = saturated_add(dithImg.at<uint8_t>(i+0,j+1),a);
+        		dithImg.at<uint8_t>(i+1,j+1) = saturated_add(dithImg.at<uint8_t>(i+1,j+1),b);
+        		dithImg.at<uint8_t>(i+1,j+0) = saturated_add(dithImg.at<uint8_t>(i+1,j+0),c);
+        		dithImg.at<uint8_t>(i+1,j-1) = saturated_add(dithImg.at<uint8_t>(i+1,j-1),d);
+      		}
+    	} 
+  	}
+
+	return dithImg;
+}
+
+uint8_t saturated_add(uint8_t val1, int8_t val2)
+{
+    int16_t val1_int = val1;
+    int16_t val2_int = val2;
+    int16_t tmp = val1_int + val2_int;
+
+    if(tmp > 255)
+    {
+        return 255;
+    }
+    else if(tmp < 0)
+    {   
+        return 0;
+    }
+    else
+    {
+        return tmp;
+    }
+}

DirectPrint/dither.h

@@ -0,0 +1,6 @@
+#include <stdint.h>
+#include <stdio.h>
+#include "opencv2/imgproc/imgproc.hpp"
+#include "opencv2/highgui/highgui.hpp"
+
+cv::Mat dither_image(cv::Mat rawImg);