diff --git a/Makefile b/Makefile
index 3a50d22..cc4f0df 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
 CXX = g++
 
-CXXFLAGS  = -Wall -Wextra -O2 -std=c++14
+CXXFLAGS  = -std=c++14 -Wall -Wextra -march=native -Ofast -fopenmp -flto
 
 DEPS = util.h vec3.h color.h ray.h camera.h hittable.h hittable_list.h sphere.h
 OBJ = wtracer.o
diff --git a/wtracer.cpp b/wtracer.cpp
index cf70ca0..f21d0ad 100644
--- a/wtracer.cpp
+++ b/wtracer.cpp
@@ -27,7 +27,8 @@ Color ray_color(const Ray& r, const Hittable& world, int depth) {
 int main() {
     const auto aspect_ratio = 16.0 / 9.0;
     //const int image_width = 1280;
-    const int image_width = 384;
+    const int image_width = 768;
+    //const int image_width = 384;
     const int image_height = static_cast<int>(image_width / aspect_ratio);
     const int samples_per_pixel = 250;
     const int max_depth = 50;
@@ -40,8 +41,11 @@ int main() {
 
     Camera cam;
 
+    Color* image = new Color[image_height*image_width];
+
     for (int j = image_height - 1; j >= 0; --j) {
         std::cerr << "\rScanlines remaining: " << j << " " << std::flush;
+        #pragma omp parallel for
         for (int i = 0; i < image_width; ++i) {
             Color pixel_color(0, 0, 0);
             for (int s = 0; s<samples_per_pixel; ++s) {
@@ -50,8 +54,15 @@ int main() {
                 Ray r = cam.get_ray(u, v);
                 pixel_color += ray_color(r, world, max_depth);
             }
-            write_color(std::cout, pixel_color, samples_per_pixel);
+            image[i*image_height+j] = pixel_color;
         }
     }
-    std::cerr << "\nDone.\n";
+    std::cerr << "\nWriting file.\n";
+    for (int j = image_height - 1; j >= 0; --j) {
+        for (int i = 0; i < image_width; ++i) {
+            write_color(std::cout, image[i*image_height+j], samples_per_pixel);
+        }
+    }
+    delete[] image;
+    std::cerr << "Done.\n";
 }