Issue 1894 - Removed "blend(red, green, blue, opacity)" and "grayscale" image conversions

imageConversion.py

 # coding: utf-8
 
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 import os
 import re
 from StringIO import StringIO
 
@@ skipping 45 matching lines @@
   )
 
   if any(im.mode in ('RGBA', 'LA', 'P') for im in (im1, im2)):
     mode += 'A'
 
   return (
     im1 if im1.mode == mode else im1.convert(mode),
     im2 if im2.mode == mode else im2.convert(mode),
   )
 
-def filter_grayscale(image, baseDir):
-  alpha = get_alpha(image)
-  image = image.convert('L')
-
-  if alpha:
-    image.putalpha(alpha)
-
-  return image
-
 def filter_contrastToAlpha(image, baseDir):
   alpha = Image.new('L', image.size, 255)
   alpha.paste(image, mask=get_alpha(image))
   alpha = ImageOps.invert(alpha)
   alpha = ImageOps.autocontrast(alpha)
 
   return Image.merge('LA', [Image.new('L', image.size), alpha])
 
-def filter_blend(image, baseDir, *args):
-  if len(args) == 2:
-    filename, opacity = args
-
-    overlay = load_image(os.path.join(
+def filter_blend(image, baseDir, filename, opacity):
+  image, overlay = ensure_same_mode(
+    image,
+    load_image(os.path.join(
       baseDir,
       *filename.split('/')
     ))
-  else:
-    red, green, blue, opacity = args
+  )
 
-    overlay = Image.new('RGB', image.size, (
-      int(red),
-      int(green),
-      int(blue),
-    ))
-
-    # if the background image has an alpha channel copy it to
-    # the overlay, so that transparent areas stay transparent.
-    alpha = get_alpha(image)
-    if alpha:
-      overlay.putalpha(alpha)
-
-  image, overlay = ensure_same_mode(image, overlay)
   return Image.blend(image, overlay, float(opacity))
 
 def convertImages(params, files):
   metadata = params['metadata']
 
   for filename, chain in metadata.items('convert_img'):
     baseDir = os.path.dirname(metadata.option_source('convert_img', filename))
     steps = re.split(r'\s*->\s*', chain)
     image = load_image(os.path.join(baseDir, *steps.pop(0).split('/')))
 
     for step in steps:
       filter, args = re.match(r'([^(]+)(?:\((.*)\))?', step).groups()
       args = re.split(r'\s*,\s*', args) if args else ()
       image = globals()['filter_' + filter](image, baseDir, *args)
 
     f = StringIO()
     f.name = filename
     image.save(f)
     files[filename] = f.getvalue()