Generate real thumbnails

boop.py

 from operator import itemgetter
 
 from jinja2 import Environment, PackageLoader, select_autoescape
+from PIL import Image
 
 from configuration import SITE_TITLE, THEME
 
         shutil.copyfile(photo["path"], photo_output_path)
 
         thumb_output_path = os.path.join(output_path, photo["thumb_url"])
-        shutil.copyfile(photo["path"], thumb_output_path)
+        generate_thumb_file(thumb_output_path, photo)
+
+
+def generate_thumb_file(output_path, photo):
+    with Image.open(photo["path"]) as image:
+        size = (440, 264)
+        w, h = image.size
+        if w > size[0] and h > size[1]:
+            # If the original file is larger in width AND height, we resize
+            # first the image to the lowest size accepted (both width and
+            # height stays greater or equal to requested size).
+            # E.g. 1200x900 is resized to 440x330
+            #      1200x600 is resized to 528x264
+            if size[0] / size[1] <= w / h:
+                w = int(max(size[1] * w / h, 1))
+                h = 264
+            else:
+                h = int(max(size[0] * h / w, 1))
+                w = 440
+            new_size = (w, h)
+
+            image.draft(None, new_size)
+            image = image.resize(new_size, Image.BICUBIC)
+
+        # We now have an image with at least w = 440 OR h = 264 (unless one of
+        # the size is smaller). But the image can still be larger than
+        # requested size, so we have to crop the image in the middle.
+        crop_box = None
+        if w > size[0]:
+            left = (w - size[0]) / 2
+            right = left + size[0]
+            crop_box = (left, 0, right, h)
+        elif h > size[1]:
+            upper = (h - size[1]) / 2
+            lower = upper + size[1]
+            crop_box = (0, upper, w, lower)
+        if crop_box is not None:
+            image = image.crop(crop_box)
+
+        # And we save the final image.
+        image.save(output_path)
 
 
 def main():

requirements.txt

-black
 Jinja2
+Pillow