#!/usr/bin/env python
##########################################################################
#
+# Copyright 2011 Jose Fonseca
# Copyright 2008-2009 VMware, Inc.
# All Rights Reserved.
#
##########################################################################/
+'''Snapshot (image) comparison script.
+'''
+
+
import sys
import os.path
-import subprocess
import optparse
+import math
+import operator
-import Image
+from PIL import Image
+from PIL import ImageChops
+from PIL import ImageEnhance
+from PIL import ImageFilter
thumb_size = 320, 320
+gaussian_kernel = ImageFilter.Kernel((3, 3), [1, 2, 1, 2, 4, 2, 1, 2, 1], 16)
+
+class Comparer:
+ '''Image comparer.'''
+
+ def __init__(self, ref_image, src_image, alpha = False):
+ if isinstance(ref_image, basestring):
+ self.ref_im = Image.open(ref_image)
+ else:
+ self.ref_im = ref_image
+
+ if isinstance(src_image, basestring):
+ self.src_im = Image.open(src_image)
+ else:
+ self.src_im = src_image
+
+ # Ignore
+ if not alpha:
+ self.ref_im = self.ref_im.convert('RGB')
+ self.src_im = self.src_im.convert('RGB')
+
+ self.diff = ImageChops.difference(self.src_im, self.ref_im)
+
+ def size_mismatch(self):
+ return self.ref_im.size != self.src_im.size
+
+ def write_diff(self, diff_image, fuzz = 0.05):
+ # make a difference image similar to ImageMagick's compare utility
+ mask = ImageEnhance.Brightness(self.diff).enhance(1.0/fuzz)
+ mask = mask.convert('L')
+
+ lowlight = Image.new('RGB', self.src_im.size, (0xff, 0xff, 0xff))
+ highlight = Image.new('RGB', self.src_im.size, (0xf1, 0x00, 0x1e))
+ diff_im = Image.composite(highlight, lowlight, mask)
+
+ diff_im = Image.blend(self.src_im, diff_im, 0xcc/255.0)
+ diff_im.save(diff_image)
+
+ def precision(self, filter=False):
+ if self.size_mismatch():
+ return 0.0
+
+ diff = self.diff
+ if filter:
+ diff = diff.filter(gaussian_kernel)
+
+ # See also http://effbot.org/zone/pil-comparing-images.htm
+ h = diff.histogram()
+ square_error = 0
+ for i in range(1, 256):
+ square_error += sum(h[i : 3*256: 256])*i*i
+ rel_error = float(square_error*2 + 1) / float(self.diff.size[0]*self.diff.size[1]*3*255*255*2)
+ bits = -math.log(rel_error)/math.log(2.0)
+ return bits
+
+ def ae(self, fuzz = 0.05):
+ # Compute absolute error
+
+ if self.size_mismatch():
+ return sys.maxint
-def compare(im, ref):
- import ImageMath
- # See http://www.pythonware.com/library/pil/handbook/imagemath.htm
- mask = ImageMath.eval("min(abs(a - b), 1)", a=im, b=ref)
- gray = ref.convert('L')
- # TODO
+ # TODO: this is approximate due to the grayscale conversion
+ h = self.diff.convert('L').histogram()
+ ae = sum(h[int(255 * fuzz) + 1 : 256])
+ return ae
def surface(html, image):
- if False:
- html.write(' <td><a href="%s"><img src="%s"/></a></td>\n' % (image, image))
- else:
+ if True:
name, ext = os.path.splitext(image)
- thumb = name + '_thumb' + ext
- if not os.path.exists(thumb) and os.path.exists(image):
+ thumb = name + '.thumb' + ext
+ if os.path.exists(image) \
+ and (not os.path.exists(thumb) \
+ or os.path.getmtime(thumb) < os.path.getmtime(image)):
im = Image.open(image)
im.thumbnail(thumb_size)
im.save(thumb)
- html.write(' <td><a href="%s"><img src="%s"/></a></td>\n' % (image, thumb))
+ else:
+ thumb = image
+ html.write(' <td><a href="%s"><img src="%s"/></a></td>\n' % (image, thumb))
+
+
+def is_image(path):
+ name = os.path.basename(path)
+ name, ext1 = os.path.splitext(name)
+ name, ext2 = os.path.splitext(name)
+ return ext1 in ('.png', '.bmp') and ext2 not in ('.diff', '.thumb')
+
+
+def find_images(prefix):
+ if os.path.isdir(prefix):
+ prefix_dir = prefix
+ else:
+ prefix_dir = os.path.dirname(prefix)
+
+ images = []
+ for dirname, dirnames, filenames in os.walk(prefix_dir, followlinks=True):
+ for filename in filenames:
+ filepath = os.path.join(dirname, filename)
+ if filepath.startswith(prefix) and is_image(filepath):
+ images.append(filepath[len(prefix):])
+
+ return images
def main():
+ global options
+
optparser = optparse.OptionParser(
- usage="\n\t%prog [options] [file] ...",
- version="%%prog")
+ usage="\n\t%prog [options] <ref_prefix> <src_prefix>")
+ optparser.add_option(
+ '-v', '--verbose',
+ action="store_true", dest="verbose", default=False,
+ help="verbose output")
optparser.add_option(
'-o', '--output', metavar='FILE',
- type="string", dest="output",
- help="output filename [stdout]")
+ type="string", dest="output", default='index.html',
+ help="output filename [default: %default]")
optparser.add_option(
- '--start', metavar='FRAME',
- type="int", dest="start", default=0,
- help="start frame [default: %default]")
+ '-f', '--fuzz',
+ type="float", dest="fuzz", default=0.05,
+ help="fuzz ratio [default: %default]")
optparser.add_option(
- '--stop', metavar='FRAME',
- type="int", dest="stop", default=0xffffffff,
- help="stop frame [default: %default]")
+ '-a', '--alpha',
+ action="store_true", dest="alpha", default=False,
+ help="take alpha channel in consideration")
optparser.add_option(
- '-f', '--fuzz',
- type="string", dest="fuzz", default='5%',
- help="fuzz [default: %default]")
+ '--overwrite',
+ action="store_true", dest="overwrite", default=False,
+ help="overwrite images")
+ optparser.add_option(
+ '--show-all',
+ action="store_true", dest="show_all", default=False,
+ help="show all images, including similar ones")
(options, args) = optparser.parse_args(sys.argv[1:])
ref_prefix = args[0]
src_prefix = args[1]
+ ref_images = find_images(ref_prefix)
+ src_images = find_images(src_prefix)
+ images = list(set(ref_images).intersection(set(src_images)))
+ images.sort()
+
if options.output:
html = open(options.output, 'wt')
else:
html.write('<html>\n')
html.write(' <body>\n')
html.write(' <table border="1">\n')
- html.write(' <tr><th>ref</th><th>src</th><th>Δ</th></tr>\n')
- frame_no = options.start
- while frame_no <= options.stop:
- ref_image = "%s%010u.png" % (ref_prefix, frame_no)
- src_image = "%s%010u.png" % (src_prefix, frame_no)
- delta_image = "%s%010u_diff.png" % (src_prefix, frame_no)
+ html.write(' <tr><th>File</th><th>%s</th><th>%s</th><th>Δ</th></tr>\n' % (ref_prefix, src_prefix))
+ failures = 0
+ for image in images:
+ ref_image = ref_prefix + image
+ src_image = src_prefix + image
+ root, ext = os.path.splitext(src_image)
+ delta_image = "%s.diff.png" % (root, )
if os.path.exists(ref_image) and os.path.exists(src_image):
+ if options.verbose:
+ sys.stdout.write('Comparing %s and %s ...' % (ref_image, src_image))
+ comparer = Comparer(ref_image, src_image, options.alpha)
+ match = comparer.ae(fuzz=options.fuzz) == 0
+ if match:
+ result = 'MATCH'
+ bgcolor = '#20ff20'
+ else:
+ result = 'MISMATCH'
+ failures += 1
+ bgcolor = '#ff2020'
+ if options.verbose:
+ sys.stdout.write(' %s\n' % (result,))
html.write(' <tr>\n')
- subprocess.call(["compare", '-metric', 'AE', '-fuzz', options.fuzz, ref_image, src_image, delta_image])
- surface(html, ref_image)
- surface(html, src_image)
- surface(html, delta_image)
+ html.write(' <td bgcolor="%s"><a href="%s">%s<a/></td>\n' % (bgcolor, ref_image, image))
+ if not match or options.show_all:
+ if options.overwrite \
+ or not os.path.exists(delta_image) \
+ or (os.path.getmtime(delta_image) < os.path.getmtime(ref_image) \
+ and os.path.getmtime(delta_image) < os.path.getmtime(src_image)):
+ comparer.write_diff(delta_image, fuzz=options.fuzz)
+ surface(html, ref_image)
+ surface(html, src_image)
+ surface(html, delta_image)
html.write(' </tr>\n')
html.flush()
- frame_no += 1
html.write(' </table>\n')
html.write(' </body>\n')
html.write('</html>\n')
+ if failures:
+ sys.exit(1)
if __name__ == '__main__':
main()
projects / apitrace / blobdiff