i&m: add operations

2 files changed, 32 insertions, 0 deletions

diff --git a/Year_2/IandM/stretching/data/lena.png b/Year_2/IandM/stretching/data/lena.png
new file mode 100644
index 0000000..59ef68a
--- /dev/null
+++ b/Year_2/IandM/stretching/data/lena.png
diff --git a/Year_2/IandM/stretching/stretching.pde b/Year_2/IandM/stretching/stretching.pde
new file mode 100644
index 0000000..0814190
--- /dev/null
+++ b/Year_2/IandM/stretching/stretching.pde
@@ -0,0 +1,32 @@
+void setup() {
+  size(512, 256);
+  PImage img = loadImage("lena.png");
+  img.resize(256, 256);
+  img.filter(GRAY);
+
+  image(img, 0, 0);
+  image(stretching(img), 256, 0);
+}
+
+PImage stretching(PImage I) {
+  PImage out = I.copy();
+  out.loadPixels();
+
+  float max = red(out.pixels[0]);
+  float min = max;
+
+  for (int i = 0; i < out.pixels.length; ++i) {
+    float t = red(out.pixels[i]);
+    if (t < min)
+      min = t;
+    if (t > max)
+      max = t;
+  }
+
+  for (int i = 0; i < out.pixels.length; ++i) {
+    out.pixels[i]= color(255*(red(out.pixels[i])-min)/(max-min));
+  }
+
+  out.updatePixels();
+  return out;
+}