Added two negative tests for ChannelDefinition.

glymur/jp2box.py

@@ -392,7 +392,7 @@ class _ICCProfile(object):
         self.header = header
 
 
-class ComponentDefinitionBox(Jp2kBox):
+class ChannelDefinitionBox(Jp2kBox):
     """Container for component definition box information.
 
     Attributes
@@ -405,27 +405,43 @@ class ComponentDefinitionBox(Jp2kBox):
         offset of the box from the start of the file.
     longname : str
         more verbose description of the box.
-    component_number : int
-        number of the component
-    component_type : int
-        type of the component
+    index : int
+        number of the channel
+    channel_type : int
+        type of the channel
     association : int
-        number of the associated color
+        index of the associated color
     """
-    def __init__(self, **kwargs):
-        Jp2kBox.__init__(self, id='', longname='Component Definition')
+    def __init__(self, index, channel_type, association, **kwargs):
+        Jp2kBox.__init__(self, id='cdef', longname='Channel Definition')
+        if len(index) != len(channel_type) or len(index) != len(association):
+            msg = "Length of channel definition box inputs must be the same."
+            raise IOError(msg)
+
+        # channel types must be one of 0, 1, 2, 65535
+        if any(x not in [0, 1, 2, 65535] for x in channel_type):
+            msg = "Channel types must be in the set of\n\n"
+            msg += "    0     - colour image data for associated color\n"
+            msg += "    1     - opacity\n"
+            msg += "    2     - premultiplied opacity\n"
+            msg += "    65535 - unspecified"
+            raise IOError(msg)
+
+        self.index = index
+        self.channel_type = channel_type
+        self.association = association
         self.__dict__.update(**kwargs)
 
     def __str__(self):
         msg = Jp2kBox.__str__(self)
         for j in range(len(self.association)):
-            color_type_string = _color_type_map_display[self.component_type[j]]
+            color_type_string = _color_type_map_display[self.channel_type[j]]
             if self.association[j] == 0:
                 assn = 'whole image'
             else:
                 assn = str(self.association[j])
-            msg += '\n    Component {0} ({1}) ==> ({2})'
-            msg = msg.format(self.component_number[j], color_type_string, assn)
+            msg += '\n    Channel {0} ({1}) ==> ({2})'
+            msg = msg.format(self.index[j], color_type_string, assn)
         return msg
 
     @staticmethod
@@ -456,17 +472,17 @@ class ComponentDefinitionBox(Jp2kBox):
         buffer = f.read(2)
         N, = struct.unpack('>H', buffer)
 
-        component_number = []
-        component_type = []
+        index = []
+        chan_type = []
         association = []
 
         buffer = f.read(N * 6)
         data = struct.unpack('>' + 'HHH' * N, buffer)
-        kwargs['component_number'] = data[0:N * 6:3]
-        kwargs['component_type'] = data[1:N * 6:3]
-        kwargs['association'] = data[2:N * 6:3]
+        index = data[0:N * 6:3]
+        channel_type = data[1:N * 6:3]
+        association = data[2:N * 6:3]
 
-        box = ComponentDefinitionBox(**kwargs)
+        box = ChannelDefinitionBox(index, channel_type, association, **kwargs)
         return box
 
 
@@ -2426,7 +2442,7 @@ class _ExifInteroperabilityIfd(_Ifd):
 # Map each box ID to the corresponding class.
 _box_with_id = {
     'asoc': AssociationBox,
-    'cdef': ComponentDefinitionBox,
+    'cdef': ChannelDefinitionBox,
     'cmap': ComponentMappingBox,
     'colr': ColourSpecificationBox,
     'jP  ': JPEG2000SignatureBox,

glymur/test/test_jp2box.py

@@ -17,6 +17,34 @@ def load_tests(loader, tests, ignore):
     return tests
 
 
+@unittest.skipIf(glymur.lib.openjp2._OPENJP2 is None,
+                 "Missing openjp2 library.")
+class TestChannelDefinition(unittest.TestCase):
+
+    def setUp(self):
+        self.jp2file = glymur.data.nemo()
+        self.j2kfile = glymur.data.goodstuff()
+
+    def tearDown(self):
+        pass
+
+    def test_bad_type(self):
+        # Channel types are limited to 0, 1, 2, 65535
+        # Should reject if not all of index, channel_type, association the
+        # same length.
+        with self.assertRaises(IOError):
+            box = glymur.jp2box.ChannelDefinitionBox(index=[0, 1, 2],
+                                                     channel_type=[0, 0, 3],
+                                                     association=[0, 1, 2])
+
+    def test_wrong_lengths(self):
+        # Should reject if not all of index, channel_type, association the
+        # same length.
+        with self.assertRaises(IOError):
+            box = glymur.jp2box.ChannelDefinitionBox(index=[0, 1, 2],
+                                                     channel_type=[0, 0],
+                                                     association=[0, 1, 2])
+
 @unittest.skipIf(glymur.lib.openjp2._OPENJP2 is None,
                  "Missing openjp2 library.")
 class TestJp2Boxes(unittest.TestCase):
@@ -225,11 +253,6 @@ class TestJp2Boxes(unittest.TestCase):
             with self.assertRaises(NotImplementedError):
                 j2k.wrap(tfile.name, boxes=boxes)
 
-    def test_default_component_definition(self):
-        # Should be able to specify a component definition box in order to,
-        # say, create an image with an alpha layer.
-        self.assertTrue(False)
-
     def test_first_2_boxes_not_jP_and_ftyp(self):
         j2k = Jp2k(self.raw_codestream)
         c = j2k.get_codestream()

glymur/test/test_opj_suite.py

@@ -4170,8 +4170,8 @@ class TestSuiteDump(unittest.TestCase):
 
         # Jp2 Header
         # Channel Definition
-        self.assertEqual(jp2.box[2].box[2].component_number, (0, 1, 2))
-        self.assertEqual(jp2.box[2].box[2].component_type, (0, 0, 0))  # color
+        self.assertEqual(jp2.box[2].box[2].index, (0, 1, 2))
+        self.assertEqual(jp2.box[2].box[2].channel_type, (0, 0, 0))  # color
         self.assertEqual(jp2.box[2].box[2].association, (3, 2, 1))  # reverse
 
     def test_NR_file3_dump(self):
@@ -6706,8 +6706,8 @@ class TestSuiteDump(unittest.TestCase):
 
         # Jp2 Header
         # Channel Definition
-        self.assertEqual(jp2.box[2].box[2].component_number, (0, 1))
-        self.assertEqual(jp2.box[2].box[2].component_type, (0, 1))   # opacity
+        self.assertEqual(jp2.box[2].box[2].index, (0, 1))
+        self.assertEqual(jp2.box[2].box[2].channel_type, (0, 1))   # opacity
         self.assertEqual(jp2.box[2].box[2].association, (0, 0))  # both main
 
         c = jp2.box[3].main_header

glymur/test/test_printing.py

@@ -676,15 +676,15 @@ class TestPrinting(unittest.TestCase):
 
     @unittest.skipIf(data_root is None,
                      "OPJ_DATA_ROOT environment variable not set")
-    def test_component_definition(self):
+    def test_channel_definition(self):
         filename = os.path.join(data_root, 'input/conformance/file2.jp2')
         j = glymur.Jp2k(filename)
         print(j.box[2].box[2])
         actual = sys.stdout.getvalue().strip()
-        lines = ['Component Definition Box (cdef) @ (81, 28)',
-                 '    Component 0 (color) ==> (3)',
-                 '    Component 1 (color) ==> (2)',
-                 '    Component 2 (color) ==> (1)']
+        lines = ['Channel Definition Box (cdef) @ (81, 28)',
+                 '    Channel 0 (color) ==> (3)',
+                 '    Channel 1 (color) ==> (2)',
+                 '    Channel 2 (color) ==> (1)']
         expected = '\n'.join(lines)
         self.assertEqual(actual, expected)