Feature: Built django-images into Pinry

django_images/utils.py

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+from PIL import Image
+
+
+# this neat function is based on easy-thumbnails
+def scale_and_crop(image, size, crop=False, upscale=False, quality=None):
+    """
+    Resize, crop and/or change quality of an image.
+
+    :param image: Source image file
+    :param type: :class:`django.core.files.images.ImageFile`
+
+    :param size: Size as width & height, zero as either means unrestricted
+    :type size: tuple of two int
+
+    :param crop: Truncate image or not
+    :type crop: bool
+
+    :param upscale: Enable scale up
+    :type upscale: bool
+
+    :param quality: Value between 1 to 95, or None for keep the same
+    :type quality: int or NoneType
+
+    :return: Handled image
+    :rtype: class:`PIL.Image`
+    """
+    # Open image and store format/metadata.
+    image.open()
+    im = Image.open(image)
+    im_format, im_info = im.format, im.info
+    if quality:
+        im_info['quality'] = quality
+
+    # Force PIL to load image data.
+    im.load()
+
+    source_x, source_y = [float(v) for v in im.size]
+    target_x, target_y = [float(v) for v in size]
+
+    if crop or not target_x or not target_y:
+        scale = max(target_x / source_x, target_y / source_y)
+    else:
+        scale = min(target_x / source_x, target_y / source_y)
+
+    # Handle one-dimensional targets.
+    if not target_x:
+        target_x = source_x * scale
+    elif not target_y:
+        target_y = source_y * scale
+
+    if scale < 1.0 or (scale > 1.0 and upscale):
+        im = im.resize((int(source_x * scale), int(source_y * scale)),
+                       resample=Image.ANTIALIAS)
+
+    if crop:
+        # Use integer values now.
+        source_x, source_y = im.size
+        # Difference between new image size and requested size.
+        diff_x = int(source_x - min(source_x, target_x))
+        diff_y = int(source_y - min(source_y, target_y))
+        if diff_x or diff_y:
+            # Center cropping (default).
+            halfdiff_x, halfdiff_y = diff_x // 2, diff_y // 2
+            box = [halfdiff_x, halfdiff_y,
+                   min(source_x, int(target_x) + halfdiff_x),
+                   min(source_y, int(target_y) + halfdiff_y)]
+            # Finally, crop the image!
+            im = im.crop(box)
+
+    # Close image and replace format/metadata, as PIL blows this away.
+    im.format, im.info = im_format, im_info
+    image.close()
+    return im