38 lines
949 B
Python
38 lines
949 B
Python
# Copyright (c) 2011 The Chromium Authors. All rights reserved.
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# Use of this source code is governed by a BSD-style license that can be
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# found in the LICENSE file.
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"""Compare two images for equality."""
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from PIL import Image
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from PIL import ImageChops
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def Compare(file1, file2, **kwargs):
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"""Compares two images to see if they're identical.
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Args:
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file1: path to first image to compare
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file2: path to second image to compare
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kwargs: unused for this operator
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Returns:
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None if the images are identical
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A tuple of (errorstring, image) if they're not
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"""
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kwargs = kwargs # unused parameter
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im1 = Image.open(file1)
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im2 = Image.open(file2)
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if im1.size != im2.size:
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return ("The images are of different size (%s vs %s)" %
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(im1.size, im2.size), im1)
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diff = ImageChops.difference(im1, im2)
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if max(diff.getextrema()) != (0, 0):
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return ("The images differ", diff)
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else:
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return None
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