--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/montage/utils.py	Mon Sep 07 15:38:38 2009 -0400
@@ -0,0 +1,50 @@
+#!/usr/bin/env python
+
+import os
+
+from PIL import Image
+
+def crop_resize(image, size):
+    """crop out the proportional middle of the image and set to the desired size"""
+    assert size[0] or size[1]
+
+    size = list(size)
+
+    if size[0] > image.size[0]:
+        return image
+    if size[1] > image.size[1]:
+        return image
+
+    image_ar = image.size[0]/float(image.size[1])
+    crop = not size[0] or not size[1]
+    if not size[1]:
+        size[1] = int(image.size[1]*size[0]/float(image.size[0]) )
+    if not size[0]:
+        size[0] = int(image.size[0]*size[1]/float(image.size[1]) )
+    size_ar = size[0]/float(size[1])
+                
+    if crop:
+        if image_ar > size_ar:
+            # trim the width
+            xoffset = int(0.5*(image.size[0] - size_ar*image.size[1]))
+            image = image.crop((xoffset, 0, image.size[0]-xoffset, image.size[1]))
+        elif image_ar < size_ar:
+            # trim the height
+            yoffset = int(0.5*(image.size[1] - image.size[0]/size_ar))
+            image = image.crop((0, yoffset, image.size[0], image.size[1] - yoffset))
+
+    return image.resize(size, Image.ANTIALIAS)
+
+if __name__ == '__main__':
+    from optparse import OptionParser
+    parser = OptionParser()
+    parser.add_option('-f', '--file')
+    parser.add_option('-W', '--width')
+    parser.add_option('-H', '--height')
+    (options, args) = parser.parse_args()
+
+    assert os.path.exists(options.file)
+
+    i = Image.open(options.file)
+    new_image = crop_resize(i, (int(options.width), int(options.height)))
+    new_image.show()