Rietveld Code Review Tool
Help | Bug tracker | Discussion group | Source code

Delta Between Two Patch Sets: imageConversion.py

Issue 5195120659922944: Issue 1883 - Convert mode P to LA to work around a PIL bug when extracting the alpha channel (Closed)
Left Patch Set: Created Jan. 27, 2015, 2:04 p.m.
Right Patch Set: Consider no transparency again and added a comment Created Jan. 27, 2015, 2:56 p.m.
Left:
Right:
Use n/p to move between diff chunks; N/P to move between comments.
Jump to:
Left: Side by side diff | Download
Right: Side by side diff | Download
« no previous file with change/comment | « no previous file | no next file » | no next file with change/comment »
Toggle Intra-line Diffs ('i') | Expand Comments ('e') | Collapse Comments ('c') | Show Comments Hide Comments ('s')
LEFTRIGHT
1 # coding: utf-8 1 # coding: utf-8
2 2
3 # This Source Code Form is subject to the terms of the Mozilla Public 3 # This Source Code Form is subject to the terms of the Mozilla Public
4 # License, v. 2.0. If a copy of the MPL was not distributed with this 4 # License, v. 2.0. If a copy of the MPL was not distributed with this
5 # file, You can obtain one at http://mozilla.org/MPL/2.0/. 5 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
6 6
7 import os 7 import os
8 import re 8 import re
9 from StringIO import StringIO 9 from StringIO import StringIO
10 10
11 try: 11 try:
12 from PIL import Image 12 from PIL import Image
13 from PIL import ImageOps 13 from PIL import ImageOps
14 except ImportError: 14 except ImportError:
15 import Image 15 import Image
16 import ImageOps 16 import ImageOps
17 17
18 def get_alpha(image): 18 def get_alpha(image):
19 if image.mode not in ('RGBA', 'LA'): 19 if image.mode in ('RGBA', 'LA'):
20 image = image.convert("LA") 20 return image.split()[image.getbands().index('A')]
21 21
22 return image.split()[image.getbands().index('A')] 22 # In order to generate an alpha channel for images using a palette, we
23 # convert the image to grayscale+alpha. Initially, we created an alpha
24 # channel by replacing opaque pixels with a high mark and transparent
25 # pixels with a low mark. However, it turned out that you can't rely on the
26 # value of Image.info['transparency'] since in some cases it might be an
27 # unparsed string instead an int indicating the value of transparent pixels.
28 if image.mode == 'P' and 'transparency' in image.info:
29 return image.convert('LA').split()[1]
23 30
24 def load_image(path): 31 def load_image(path):
25 image = Image.open(path) 32 image = Image.open(path)
26 # Make sure the image is loaded, some versions of PIL load images lazily. 33 # Make sure the image is loaded, some versions of PIL load images lazily.
27 image.load() 34 image.load()
28 return image 35 return image
29 36
30 def ensure_same_mode(im1, im2): 37 def ensure_same_mode(im1, im2):
31 # if both images already have the same mode (and palette, in 38 # if both images already have the same mode (and palette, in
32 # case of mode P), don't convert anything. Images with mode P, 39 # case of mode P), don't convert anything. Images with mode P,
(...skipping 75 matching lines...) Expand 10 before | Expand all | Expand 10 after
108 115
109 for step in steps: 116 for step in steps:
110 filter, args = re.match(r'([^(]+)(?:\((.*)\))?', step).groups() 117 filter, args = re.match(r'([^(]+)(?:\((.*)\))?', step).groups()
111 args = re.split(r'\s*,\s*', args) if args else () 118 args = re.split(r'\s*,\s*', args) if args else ()
112 image = globals()['filter_' + filter](image, baseDir, *args) 119 image = globals()['filter_' + filter](image, baseDir, *args)
113 120
114 f = StringIO() 121 f = StringIO()
115 f.name = filename 122 f.name = filename
116 image.save(f) 123 image.save(f)
117 files[filename] = f.getvalue() 124 files[filename] = f.getvalue()
LEFTRIGHT
« no previous file | no next file » | Toggle Intra-line Diffs ('i') | Expand Comments ('e') | Collapse Comments ('c') | Toggle Comments ('s')

Powered by Google App Engine
This is Rietveld