Merge branch 'image-backend-tweaks' of https://github.com/kaedroho/wagtail into kaedroho-image-backend-tweaks

wagtail/wagtailimages/backends/base.py

@@ -1,6 +1,7 @@
 from django.conf import settings
 from django.core.exceptions import ImproperlyConfigured
 
+
 class InvalidImageBackendError(ImproperlyConfigured):
     pass
 
@@ -8,23 +9,22 @@ class InvalidImageBackendError(ImproperlyConfigured):
 class BaseImageBackend(object):
     def __init__(self, params):
         self.quality = getattr(settings, 'IMAGE_COMPRESSION_QUALITY', 85)
-        
+
     def open_image(self, input_file):
         """
-        Open an image and return the backend specific image object to pass 
-        to other methods. The object return has to have a size  attribute 
+        Open an image and return the backend specific image object to pass
+        to other methods. The object return has to have a size  attribute
         which is a tuple with the width and height of the image and a format
         attribute with the format of the image.
         """
         raise NotImplementedError('subclasses of BaseImageBackend must provide an open_image() method')
-        
-    
+
     def save_image(self, image, output):
         """
         Save the image to the output
         """
         raise NotImplementedError('subclasses of BaseImageBackend must provide a save_image() method')
-        
+
     def resize(self, image, size):
         """
         resize image to the requested size, using highest quality settings
@@ -32,11 +32,9 @@ class BaseImageBackend(object):
         """
         raise NotImplementedError('subclasses of BaseImageBackend must provide an resize() method')
 
-
     def crop_to_centre(self, image, size):
         raise NotImplementedError('subclasses of BaseImageBackend must provide a crop_to_centre() method')
 
-
     def resize_to_max(self, image, size):
         """
         Resize image down to fit within the given dimensions, preserving aspect ratio.
@@ -58,10 +56,8 @@ class BaseImageBackend(object):
             final_size = (target_width, int(original_height * horz_scale))
         else:
             final_size = (int(original_width * vert_scale), target_height)
-        
-        return self.resize(image, final_size)
-        
 
+        return self.resize(image, final_size)
 
     def resize_to_min(self, image, size):
         """
@@ -87,7 +83,6 @@ class BaseImageBackend(object):
 
         return self.resize(image, final_size)
 
-
     def resize_to_width(self, image, target_width):
         """
         Resize image down to the given width, preserving aspect ratio.
@@ -104,7 +99,6 @@ class BaseImageBackend(object):
 
         return self.resize(image, final_size)
 
-
     def resize_to_height(self, image, target_height):
         """
         Resize image down to the given height, preserving aspect ratio.
@@ -121,7 +115,6 @@ class BaseImageBackend(object):
 
         return self.resize(image, final_size)
 
-
     def resize_to_fill(self, image, size):
         """
         Resize down and crop image to fill the given dimensions. Most suitable for thumbnails.

wagtail/wagtailimages/backends/pillow.py

@@ -1,6 +1,9 @@
-from base import BaseImageBackend
+from __future__ import absolute_import
+
+from .base import BaseImageBackend
 import PIL.Image
 
+
 class PillowBackend(BaseImageBackend):
     def __init__(self, params):
         super(PillowBackend, self).__init__(params)
@@ -32,4 +35,4 @@ class PillowBackend(BaseImageBackend):
         top = (original_height - final_height) / 2
         return image.crop(
             (left, top, left + final_width, top + final_height)
-        )
+        )

wagtail/wagtailimages/backends/wand.py

@@ -1,8 +1,9 @@
 from __future__ import absolute_import
 
 from .base import BaseImageBackend
-
 from wand.image import Image
+from wand.api import library
+
 
 class WandBackend(BaseImageBackend):
     def __init__(self, params):
@@ -10,6 +11,7 @@ class WandBackend(BaseImageBackend):
 
     def open_image(self, input_file):
         image = Image(file=input_file)
+        image.wand = library.MagickCoalesceImages(image.wand)
         return image
 
     def save_image(self, image, output, format):
@@ -18,8 +20,9 @@ class WandBackend(BaseImageBackend):
         image.save(file=output)
 
     def resize(self, image, size):
-        image.resize(size[0], size[1])
-        return image
+        new_image = image.clone()
+        new_image.resize(size[0], size[1])
+        return new_image
 
     def crop_to_centre(self, image, size):
         (original_width, original_height) = image.size
@@ -34,7 +37,9 @@ class WandBackend(BaseImageBackend):
 
         left = (original_width - final_width) / 2
         top = (original_height - final_height) / 2
-        image.crop(
+
+        new_image = image.clone()
+        new_image.crop(
             left=left, top=top, right=left + final_width, bottom=top + final_height
         )
-        return image
+        return new_image

wagtail/wagtailimages/models.py

@@ -194,27 +194,25 @@ class Filter(models.Model):
         generate an output image with this filter applied, returning it
         as another django.core.files.File object
         """
-        
         backend = get_image_backend(backend_name)
-        
+
         if not self.method:
             self._parse_spec_string()
-        
+
         # If file is closed, open it
         input_file.open('rb')
         image = backend.open_image(input_file)
         file_format = image.format
-        
+
         method = getattr(backend, self.method_name)
 
         image = method(image, self.method_arg)
 
         output = StringIO.StringIO()
         backend.save_image(image, output, file_format)
-        
+
         # and then close the input file
         input_file.close()
-        
 
         # generate new filename derived from old one, inserting the filter spec string before the extension
         input_filename_parts = os.path.basename(input_file.name).split('.')
@@ -224,7 +222,6 @@ class Filter(models.Model):
         output_filename = '.'.join(output_filename_parts)
 
         output_file = File(output, name=output_filename)
-        
 
         return output_file
 

wagtail/wagtailimages/tests.py

@@ -84,10 +84,10 @@ class TestRenditions(TestCase):
         # default backend should be pillow
         backend = get_image_backend()
         self.assertTrue(isinstance(backend, PillowBackend))
-        
+
     def test_minification(self):
         rendition = self.image.get_rendition('width-400')
-        
+
         # Check size
         self.assertEqual(rendition.width, 400)
         self.assertEqual(rendition.height, 300)
@@ -121,7 +121,7 @@ class TestRenditions(TestCase):
 
         # Check that they are the same object
         self.assertEqual(first_rendition, second_rendition)
-        
+
 
 class TestRenditionsWand(TestCase):
     def setUp(self):
@@ -141,18 +141,18 @@ class TestRenditionsWand(TestCase):
 
     def test_minification(self):
         rendition = self.image.get_rendition('width-400')
-        
+
         # Check size
         self.assertEqual(rendition.width, 400)
         self.assertEqual(rendition.height, 300)
-        
+
     def test_resize_to_max(self):
         rendition = self.image.get_rendition('max-100x100')
-        
+
         # Check size
         self.assertEqual(rendition.width, 100)
         self.assertEqual(rendition.height, 75)
-        
+
     def test_resize_to_min(self):
         rendition = self.image.get_rendition('min-120x120')
 
@@ -174,7 +174,7 @@ class TestRenditionsWand(TestCase):
 
         # Check that they are the same object
         self.assertEqual(first_rendition, second_rendition)
-        
+
 
 class TestImageTag(TestCase):
     def setUp(self):