Data update

Task/Image-convolution/OCaml/image-convolution-1.ml

@@ -0,0 +1,55 @@
+let get_rgb img x y =
+  let _, r_channel,_,_ = img in
+  let width = Bigarray.Array2.dim1 r_channel
+  and height = Bigarray.Array2.dim2 r_channel in
+  if (x < 0) || (x >= width) then (0,0,0) else
+  if (y < 0) || (y >= height) then (0,0,0) else  (* feed borders with black *)
+  get_pixel img x y
+
+
+let convolve_get_value img kernel divisor offset = fun x y ->
+  let sum_r = ref 0.0
+  and sum_g = ref 0.0
+  and sum_b = ref 0.0 in
+
+  for i = -1 to 1 do
+    for j = -1 to 1 do
+      let r, g, b = get_rgb img (x+i) (y+j) in
+      sum_r := !sum_r +. kernel.(j+1).(i+1) *. (float r);
+      sum_g := !sum_g +. kernel.(j+1).(i+1) *. (float g);
+      sum_b := !sum_b +. kernel.(j+1).(i+1) *. (float b);
+    done;
+  done;
+  ( !sum_r /. divisor +. offset,
+    !sum_g /. divisor +. offset,
+    !sum_b /. divisor +. offset )
+
+
+let color_to_int (r,g,b) =
+  (truncate r,
+   truncate g,
+   truncate b)
+
+let bounded (r,g,b) =
+  ((max 0 (min r 255)),
+   (max 0 (min g 255)),
+   (max 0 (min b 255)))
+
+
+let convolve_value ~img ~kernel ~divisor ~offset =
+  let _, r_channel,_,_ = img in
+  let width = Bigarray.Array2.dim1 r_channel
+  and height = Bigarray.Array2.dim2 r_channel in
+
+  let res = new_img ~width ~height in
+
+  let conv = convolve_get_value img kernel divisor offset in
+
+  for y = 0 to pred height do
+    for x = 0 to pred width do
+      let color = conv x y in
+      let color = color_to_int color in
+      put_pixel res (bounded color) x y;
+    done;
+  done;
+  (res)