diff --git a/gen_tiles.py b/gen_tiles.py
index 87487a7..e27151f 100644
--- a/gen_tiles.py
+++ b/gen_tiles.py
@@ -1,45 +1,139 @@
-import cv2 
+from concurrent.futures import ThreadPoolExecutor
+from itertools import product
+from pathlib import Path
+from typing import Tuple, List
+import cv2
 import numpy as np
 import os
 import sys
 from tqdm import tqdm
 import math
 import conf
+import multiprocessing
+
+import click
+
 
 # DEPTH = 4 -> 4 * 4 * 4 = 64 colors
 DEPTH = conf.DEPTH
 # list of rotations, in degrees, to apply over the original image
 ROTATIONS = conf.ROTATIONS
+THREADS = multiprocessing.cpu_count()
+
+
+def get_tile_dir(img_dir: Path, img_name: str) -> Path:
+    tile_dir = img_dir / Path(f"gen_{img_name}")
+
+    if not tile_dir.exists():
+        tile_dir.mkdir()
+
+    return tile_dir
+
+
+def get_img(img: Path) -> np.array:
+    img = cv2.imread(str(img), cv2.IMREAD_UNCHANGED)
+    return img.astype("float")
+
+
+def get_dimensions(img: np.array) -> Tuple[int, int, Tuple[float, float]]:
+    height, width = img.shape[:2]
+    center = (width / 2, height / 2)
+
+    return height, width, center
+
+
+def make_rotation(
+    img_name: str,
+    ext: str,
+    tile_dir: Path,
+    new_img: np.array,
+    dimensions: Tuple[int, int, Tuple[float, float]],
+    rotation: float,
+    colors: Tuple[float, float, float],
+    bar: tqdm,
+):
+    height, width, center = dimensions
+    b, g, r = colors
+
+    rotation_matrix = cv2.getRotationMatrix2D(center, rotation, 1)
+    abs_cos = abs(rotation_matrix[0, 0])
+    abs_sin = abs(rotation_matrix[0, 1])
+    new_w = int(height * abs_sin + width * abs_cos)
+    new_h = int(height * abs_cos + width * abs_sin)
+    rotation_matrix[0, 2] += new_w / 2 - center[0]
+    rotation_matrix[1, 2] += new_h / 2 - center[1]
+    cv2.imwrite(
+        f"{tile_dir}/{img_name}_{round(r,1)}_{round(g,1)}_{round(b,1)}_r{rotation}.{ext}",
+        cv2.warpAffine(new_img, rotation_matrix, (new_w, new_h)),
+        # compress image
+        [cv2.IMWRITE_PNG_COMPRESSION, 9],
+    )
+    bar.update()
+
+
+def generate_tiles(
+    img: np.array,
+    img_name: str,
+    ext: str,
+    tile_dir: Path,
+    depth: int,
+    rotations: List[int],
+    pool: ThreadPoolExecutor,
+):
+    dimensions = get_dimensions(img)
+    b_range = np.arange(0, 1.01, 1 / depth)
+    g_range = np.arange(0, 1.01, 1 / depth)
+    r_range = np.arange(0, 1.01, 1 / depth)
+    operations = len(b_range) ** 3 * len(rotations)
+    progress_bar = tqdm(total=operations)
+
+    for b, g, r in product(b_range, g_range, r_range):
+        colors = b, g, r
+        new_img = img * [b, g, r, 1]
+        new_img = new_img.astype("uint8")
+        for rotation in rotations:
+            pool.submit(
+                make_rotation,
+                img_name,
+                ext,
+                tile_dir,
+                new_img,
+                dimensions,
+                rotation,
+                colors,
+                progress_bar,
+            )
+
+
+@click.command()
+@click.option(
+    "-d",
+    "--depth",
+    default=DEPTH,
+    help="Color depth.",
+    show_default=True,
+    type=click.INT,
+)
+@click.option(
+    "-r",
+    "--rotations",
+    default=ROTATIONS,
+    help="Rotations.",
+    multiple=True,
+    show_default=True,
+    type=click.INT,
+)
+@click.argument("img", type=click.Path(exists=True))
+def cmd(img: str, depth: int, rotations: List[int]):
+    img_path = Path(img)
+    img_dir = img_path.parent
+    img_name, ext = img_path.name.split(".")
+    tile_dir = get_tile_dir(img_dir, img_name)
+    img = get_img(img_path)
+
+    with ThreadPoolExecutor(max_workers=THREADS) as pool:
+        generate_tiles(img, img_name, ext, tile_dir, depth, rotations, pool)
+
 
-img_path = sys.argv[1]
-img_dir = os.path.dirname(img_path)
-img_name, ext = os.path.basename(img_path).rsplit('.', 1)
-out_folder = img_dir + '/gen_' + img_name
-
-if not os.path.exists(out_folder):
-    os.mkdir(out_folder)
-
-img = cv2.imread(img_path, cv2.IMREAD_UNCHANGED)
-img = img.astype('float')
-
-height, width = img.shape[:2]
-center = (width/2, height/2)
-
-for b in tqdm(np.arange(0, 1.01, 1 / DEPTH)):
-    for g in np.arange(0, 1.01, 1 / DEPTH):
-        for r in np.arange(0, 1.01, 1 / DEPTH):
-            new_img = img * [b, g, r, 1]
-            new_img = new_img.astype('uint8')
-            for rotation in ROTATIONS:
-                rotation_matrix = cv2.getRotationMatrix2D(center, rotation, 1)
-                abs_cos = abs(rotation_matrix[0,0])
-                abs_sin = abs(rotation_matrix[0,1])
-                new_w = int(height * abs_sin + width * abs_cos)
-                new_h = int(height * abs_cos + width * abs_sin)
-                rotation_matrix[0, 2] += new_w/2 - center[0]
-                rotation_matrix[1, 2] += new_h/2 - center[1]
-                cv2.imwrite(
-                    f'{out_folder}/{img_name}_{round(r,1)}_{round(g,1)}_{round(b,1)}_r{rotation}.{ext}',
-                    cv2.warpAffine(new_img, rotation_matrix, (new_w, new_h)),
-                    # compress image
-                    [cv2.IMWRITE_PNG_COMPRESSION, 9])
+if __name__ == "__main__":
+    cmd()
diff --git a/requirements.txt b/requirements.txt
index 9c0b5b3..13d2c43 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,3 +1,4 @@
 opencv-python
 numpy
-tqdm
\ No newline at end of file
+tqdm
+click
\ No newline at end of file