Include jpeg test

Makefile

@@ -34,4 +34,7 @@ infragram:	infragram.cpp jpeg.hpp ndvi.hpp
 ndvi:	ndvi.cpp ndvi.hpp jpeg.hpp
 	$(CXX) $(CXX_FLAGS) $(INCLUDE) -o $@ $< $(LIBS)
 
+tests:	jpeg
 
+jpeg:	jpeg.cpp jpeg.hpp
+	$(CXX) $(CXX_FLAGS) $(INCLUDE) -o $@ $< $(LIBS)

jpeg.cpp

@@ -0,0 +1,76 @@
+/* Jpeg wrapper test program
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <jpeglib.h>
+#include <string.h>
+#include <errno.h>
+#include <stdlib.h>
+
+#include "jpeg.hpp"
+
+
+
+using namespace std;
+
+static void rgb_prescription(const int x, const int y, const int width, const int height, rgb_t &rgb) {
+	rgb.r = 255*((float)x/(float)width);
+	rgb.g = 255*((float)y/(float)height);
+	rgb.b = 0;
+}
+
+static inline int diff(const rgb_t &a, const rgb_t &b) {
+	return abs(a.r-b.r) + abs(a.g-b.g) + abs(a.b-b.b);
+}
+
+
+int main() {
+	const char* filename = "test.jpeg";
+	
+	// Create and write a jpeg
+	Jpeg jpeg(255,255);
+	rgb_t rgb;
+	
+	for (int x=0;x<jpeg.width;x++) {
+		for(int y=0;y<jpeg.height;y++) {
+			rgb_prescription(x,y, jpeg.width, jpeg.height, rgb);
+			jpeg.set(x,y,rgb);
+		}
+	}
+	jpeg.write(filename);
+	
+	// Read in and check values
+	try {
+	Jpeg input(filename);
+		if(input.width != jpeg.width) throw "Width mismatch";
+		if(input.height != jpeg.height) throw "Width mismatch";
+		
+		
+		rgb_t rgb1, rgb2;
+		int errs = 0;
+		for (int x=0;x<input.width;x++) {
+			for(int y=0;y<input.height;y++) {
+				rgb1 = input.rgb(x, y);
+				rgb2 = jpeg.rgb(x, y);
+				
+				const int x = diff(rgb1, rgb2);
+				if (x > 5) {
+					cerr << "Pixel (" << x << "," << y << ") differs " << x << " value points!" << endl;
+					errs++;
+				}
+			}
+		}
+		
+		if(errs > 0) throw "Pixel errors";
+	} catch (const char* msg) {
+		cerr << "Error: " << msg << endl;
+		return EXIT_FAILURE;
+	}
+	
+	::unlink(filename);
+	cout << "All good" << endl;
+	return EXIT_SUCCESS;
+}
+
+