Fixes to MultiImage, added tests for it, plus a test TIF image.

scikits/image/io/io.py

@@ -44,23 +44,25 @@ class MultiImage(object):
 
     Examples
     --------
-    >>> img = MultiImage(fname)  #doctest: +SKIP
+    >>> import os.path
+    >>> fname = os.path.join('tests', 'data', 'multipage.tif')
+
+    >>> img = MultiImage(fname)
     >>> len(img)
-    3
+    2
     >>> for frame in img:
     ...     print frame.shape
-    (576, 384)
-    (576, 384)
-    (576, 384)
+    (15, 10)
+    (15, 10)
     """
     def __init__(self, filename, conserve_memory=True):
         """Load a multi-img"""
         self._filename = filename
-        self.conserve_memory = conserve_memory
+        self._conserve_memory = conserve_memory
         self._cached = None
 
         img = Image.open(self._filename)
-        if self.conserve_memory:
+        if self._conserve_memory:
             self._numframes = self._find_numframes(img)
         else:
             self._frames = self._getallframes(img)
@@ -70,6 +72,10 @@ class MultiImage(object):
     def filename(self):
         return self._filename
 
+    @property
+    def conserve_memory(self):
+        return self._conserve_memory
+
     def _find_numframes(self, img):
         """Find the number of frames in the multi-img."""
         i = 0

scikits/image/io/tests/test_io.py

@@ -44,6 +44,48 @@ class TestImageCollection():
         assert self.collection[1].ndim == 2
 
 
+class TestMultiImage():
+
+    def setUp(self):
+        # This multipage TIF file was created with imagemagick:
+        # convert im1.tif im2.tif -adjoin multipage.tif
+        self.img = io.MultiImage(os.path.join('data', 'multipage.tif'))
+
+    def test_len(self):
+        assert len(self.img) == 2
+
+    def test_getitem(self):
+        num = len(self.img)
+        for i in range(-num, num):
+            assert type(self.img[i]) is np.ndarray
+        assert_array_almost_equal(self.img[0],
+                                  self.img[-num])
+
+        #assert_raises expects a callable, hence this do-very-little func
+        def return_img(n):
+            return self.img[n]
+        assert_raises(IndexError, return_img, num)
+        assert_raises(IndexError, return_img, -num-1)
+
+    def test_files_property(self):
+        assert isinstance(self.img.filename, basestring)
+
+        def set_filename(f):
+            self.img.filename = f
+        assert_raises(AttributeError, set_filename, 'newfile')
+
+    def test_conserve_memory_property(self):
+        assert isinstance(self.img.conserve_memory, bool)
+
+        def set_mem(val):
+            self.img.conserve_memory = val
+        assert_raises(AttributeError, set_mem, True)
+
+
+
+
+
+
 if __name__ == "__main__":
     run_module_suite()