start colour unit test

python/test_colour.py

@@ -0,0 +1,136 @@
+#!/usr/bin/python
+
+import unittest
+import math
+
+#import logging
+#logging.basicConfig(level = logging.DEBUG)
+
+from gi.repository import Vips 
+from vips8 import vips
+
+unsigned_formats = [Vips.BandFormat.UCHAR, 
+                    Vips.BandFormat.USHORT, 
+                    Vips.BandFormat.UINT] 
+signed_formats = [Vips.BandFormat.CHAR, 
+                  Vips.BandFormat.SHORT, 
+                  Vips.BandFormat.INT] 
+float_formats = [Vips.BandFormat.FLOAT, 
+                 Vips.BandFormat.DOUBLE]
+complex_formats = [Vips.BandFormat.COMPLEX, 
+                   Vips.BandFormat.DPCOMPLEX] 
+int_formats = unsigned_formats + signed_formats
+noncomplex_formats = int_formats + float_formats
+all_formats = int_formats + float_formats + complex_formats
+
+colour_colourspaces = [Vips.Interpretation.XYZ,
+                       Vips.Interpretation.LAB,
+                       Vips.Interpretation.LABQ,
+                       Vips.Interpretation.LCH,
+                       Vips.Interpretation.CMC,
+                       Vips.Interpretation.LABS,
+                       Vips.Interpretation.SCRGB,
+                       Vips.Interpretation.SRGB,
+                       Vips.Interpretation.RGB16,
+                       Vips.Interpretation.YXY]
+mono_colourspaces = [Vips.Interpretation.GREY16,
+                     Vips.Interpretation.B_W]
+all_colourspaces = colour_colourspaces + mono_colourspaces
+
+# an expanding zip ... if either of the args is not a list, duplicate it down
+# the other
+def zip_expand(x, y):
+    if isinstance(x, list) and isinstance(y, list):
+        return zip(x, y)
+    elif isinstance(x, list):
+        return [[i, y] for i in x]
+    elif isinstance(y, list):
+        return [[x, j] for j in y]
+    else:
+        return [[x, y]]
+
+# run a 1-ary function on a thing -- loop over elements if the 
+# thing is a list
+def run_fn(fn, x):
+    if isinstance(x, list):
+        return [fn(i) for i in x]
+    else:
+        return fn(x)
+
+# run a 2-ary function on two things -- loop over elements pairwise if the 
+# things are lists
+def run_fn2(fn, x, y):
+    if isinstance(x, Vips.Image) or isinstance(y, Vips.Image):
+        return fn(x, y)
+    elif isinstance(x, list) or isinstance(y, list):
+        return [fn(i, j) for i, j in zip_expand(x, y)]
+    else:
+        return fn(x, y)
+
+class TestColour(unittest.TestCase):
+    # test a pair of things which can be lists for approx. equality
+    def assertAlmostEqualObjects(self, a, b, places = 4, msg = ''):
+        #print 'assertAlmostEqualObjects %s = %s' % (a, b)
+        for x, y in zip_expand(a, b):
+            self.assertAlmostEqual(x, y, places = places, msg = msg)
+
+    # run a function on an image and on a single pixel, the results 
+    # should match 
+    def run_cmp(self, message, im, x, y, fn):
+        a = im.getpoint(x, y)
+        v1 = fn(a)
+        im2 = fn(im)
+        v2 = im2.getpoint(x, y)
+        self.assertAlmostEqualObjects(v1, v2, msg = message)
+
+    # run a function on a pair of images and on a pair of pixels, the results 
+    # should match 
+    def run_cmp2(self, message, left, right, x, y, fn):
+        a = left.getpoint(x, y)
+        b = right.getpoint(x, y)
+        v1 = fn(a, b)
+        after = fn(left, right)
+        v2 = after.getpoint(x, y)
+        self.assertAlmostEqualObjects(v1, v2, msg = message)
+
+    # run a function on a pair of images
+    # 50,50 and 10,10 should have different values on the test image
+    def run_test2(self, message, left, right, fn):
+        self.run_cmp2(message, left, right, 50, 50, 
+                      lambda x, y: run_fn2(fn, x, y))
+        self.run_cmp2(message, left, right, 10, 10, 
+                      lambda x, y: run_fn2(fn, x, y))
+
+    def setUp(self):
+        im = Vips.Image.mask_ideal(100, 100, 0.5, optical = True)
+        self.colour = im * [1, 2, 3] + [2, 3, 4]
+        self.mono = self.colour.extract_band(1)
+        self.all_images = [self.mono, self.colour]
+
+    def test_colourspace(self):
+        # mid-grey in Lab
+        test = Vips.Image.black(100, 100) + [50, 0, 0]
+        test = test.copy(interpretation = Vips.Interpretation.LAB)
+
+        im = test
+        for col in colour_colourspaces + [Vips.Interpretation.LAB]:
+            im = im.colourspace(col)
+            self.assertEqual(im.interpretation, col)
+
+        before = test.getpoint(10, 10)
+        after = im.getpoint(10, 10)
+        self.assertAlmostEqualObjects(before, after, places = 1)
+
+        test = Vips.Image.black(100, 100) + [50, 0, 0]
+        test = test.copy(interpretation = Vips.Interpretation.LAB)
+        im = im.colourspace(Vips.Interpretation.XYZ)
+        after = im.getpoint(10, 10)
+
+        print 'after =', after
+        self.assertAlmostEqualObjects(after, [17.5064, 18.4187, 20.0547])
+    
+
+
+
+if __name__ == '__main__':
+    unittest.main()