* Lots of changes, code cleanup, import/export in GUI.

src/lib/thumbnail.py

@@ -0,0 +1,116 @@
+# This Python file uses the following encoding: utf-8
+#
+#  Author: Roman 'gryf' Dobosz  gryf@elysium.pl
+#
+#  Copyright (C) 2007 by Roman 'gryf' Dobosz
+#
+#  This file is part of pyGTKtalog.
+#
+#  This program is free software; you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation; either version 2 of the License, or
+#  (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program; if not, write to the Free Software
+#  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+
+#  -------------------------------------------------------------------------
+
+from tempfile import mkstemp
+from hashlib import sha512
+from shutil import move
+from os import path
+import sys
+
+from lib import EXIF
+import Image
+
+class Thumbnail(object):
+    """Class for generate/extract thumbnail from image file"""
+
+    def __init__(self, filename=None, base=''):
+        self.thumb_x = 160
+        self.thumb_y = 160
+        self.filename = filename
+        self.base = base
+        self.sha512 = sha512(open(filename).read()).hexdigest()
+        self.thumbnail_path = path.join(self.base, self.sha512 + "_t")
+
+    def save(self):
+        """Save thumbnail into specific directory structure
+        return filename base and exif object or None"""
+        exif = {}
+        orientations = {2: Image.FLIP_LEFT_RIGHT,  # Mirrored horizontal
+                        3: Image.ROTATE_180,       # Rotated 180
+                        4: Image.FLIP_TOP_BOTTOM,  # Mirrored vertical
+                        5: Image.ROTATE_90,        # Mirrored horizontal then
+                                                   # rotated 90 CCW
+                        6: Image.ROTATE_270,       # Rotated 90 CW
+                        7: Image.ROTATE_270,       # Mirrored horizontal then
+                                                   # rotated 90 CW
+                        8: Image.ROTATE_90}        # Rotated 90 CCW
+        flips = {7: Image.FLIP_LEFT_RIGHT, 5: Image.FLIP_LEFT_RIGHT}
+        
+        image_file = open(self.filename, 'rb')
+        try:
+            exif = EXIF.process_file(image_file)
+        except:
+            if __debug__:
+                print "exception", sys.exc_info()[0], "raised with file:"
+                print self.filename
+        finally:
+            image_file.close()
+
+        if path.exists(self.thumbnail_path):
+            if __debug__:
+                print "file", self.filename, "with hash", self.sha512, "exists"
+            return self.sha512, exif
+            
+        if 'JPEGThumbnail' in exif:
+            if __debug__:
+                print self.filename, "exif thumb"
+            exif_thumbnail = exif['JPEGThumbnail']
+            thumb_file = open(self.thumbnail_path, 'wb')
+            thumb_file.write(exif_thumbnail)
+            thumb_file.close()
+            
+            if 'Image Orientation' in exif:
+                orient = exif['Image Orientation'].values[0]
+                if orient > 1 and orient in orientations:
+                    temp_image_path = mkstemp()[1]
+                    
+                    thumb_image = Image.open(self.thumbnail_path)
+                    tmp_thumb_img = thumb_image.transpose(orientations[orient])
+                    
+                    if orient in flips:
+                        tmp_thumb_img = tmp_thumb_img.transpose(flips[orient])
+
+                    if tmp_thumb_img:
+                        tmp_thumb_img.save(temp_image_path, 'JPEG')
+                        move(temp_image_path, self.thumbnail_path)
+            return self.sha512, exif
+        else:
+            if __debug__:
+                print self.filename, "no exif thumb"
+            thumb = self.__scale_image()
+            if thumb:
+                thumb.save(self.thumbnail_path, "JPEG")
+                return self.sha512, exif
+        return None, exif
+
+    def __scale_image(self):
+        """create thumbnail. returns image object or None"""
+        try:
+            image_thumb = Image.open(self.filename).convert('RGB')
+        except:
+            return None
+        it_x, it_y = image_thumb.size
+        if it_x > self.thumb_x or it_y > self.thumb_y:
+            image_thumb.thumbnail((self.thumb_x, self.thumb_y), Image.ANTIALIAS)
+        return image_thumb