From 09d96c17693048b0ec8b6610cd5f4f4247cb3075 Mon Sep 17 00:00:00 2001
From: jevans <john.g.evans.ne@gmail.com>
Date: Thu, 14 Nov 2013 20:53:29 -0500
Subject: [PATCH] Handling the case of signed data as well.  #140.

---
 glymur/codestream.py           |  2 +-
 glymur/test/test_codestream.py | 24 +++++++++++++++++++++---
 2 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/glymur/codestream.py b/glymur/codestream.py
index 4274b61..fc94d32 100644
--- a/glymur/codestream.py
+++ b/glymur/codestream.py
@@ -1510,7 +1510,7 @@ class SIZsegment(Segment):
         lst = []
         for bitdepth, signed in zip(self.bitdepth, self.signed):
             if signed:
-                lst.append((bitdepth - 1) & 0x80)
+                lst.append((bitdepth - 1) | 0x80)
             else:
                 lst.append(bitdepth - 1)
         self.ssiz = tuple(lst)
diff --git a/glymur/test/test_codestream.py b/glymur/test/test_codestream.py
index 39e3b16..768bf7f 100644
--- a/glymur/test/test_codestream.py
+++ b/glymur/test/test_codestream.py
@@ -32,8 +32,6 @@ except:
     raise
 
 
-@unittest.skipIf(DATA_ROOT is None,
-                 "OPJ_DATA_ROOT environment variable not set")
 class TestCodestream(unittest.TestCase):
     """Test suite for unusual codestream cases."""
 
@@ -43,6 +41,8 @@ class TestCodestream(unittest.TestCase):
     def tearDown(self):
         pass
 
+    @unittest.skipIf(DATA_ROOT is None,
+                     "OPJ_DATA_ROOT environment variable not set")
     @unittest.skipIf(os.name == "nt", "Temporary file issue on window.")
     def test_reserved_marker_segment(self):
         """Reserved marker segments are ok."""
@@ -74,6 +74,8 @@ class TestCodestream(unittest.TestCase):
             self.assertEqual(codestream.segment[2].length, 3)
             self.assertEqual(codestream.segment[2].data, b'\x00')
 
+    @unittest.skipIf(DATA_ROOT is None,
+                     "OPJ_DATA_ROOT environment variable not set")
     @unittest.skipIf(sys.hexversion < 0x03020000,
                      "Uses features introduced in 3.2.")
     @unittest.skipIf(os.name == "nt", "Temporary file issue on window.")
@@ -105,6 +107,8 @@ class TestCodestream(unittest.TestCase):
                 self.assertEqual(codestream.segment[2].length, 3)
                 self.assertEqual(codestream.segment[2].data, b'\x00')
 
+    @unittest.skipIf(DATA_ROOT is None,
+                     "OPJ_DATA_ROOT environment variable not set")
     def test_psot_is_zero(self):
         """Psot=0 in SOT is perfectly legal.  Issue #78."""
         filename = os.path.join(DATA_ROOT,
@@ -117,7 +121,7 @@ class TestCodestream(unittest.TestCase):
         self.assertEqual(codestream.segment[-1].marker_id, 'EOC')
 
 
-    def test_siz_segment_ssiz(self):
+    def test_siz_segment_ssiz_unsigned(self):
         """ssiz attribute to be removed in future release"""
         j = Jp2k(self.jp2file)
         codestream = j.get_codestream()
@@ -128,6 +132,20 @@ class TestCodestream(unittest.TestCase):
         self.assertEqual(codestream.segment[1].ssiz, (7, 7, 7))
 
 
+    @unittest.skipIf(DATA_ROOT is None,
+                     "OPJ_DATA_ROOT environment variable not set")
+    def test_siz_segment_ssiz_signed(self):
+        """ssiz attribute to be removed in future release"""
+        filename = os.path.join(DATA_ROOT, 'input/conformance/p0_03.j2k')
+        j = Jp2k(filename)
+        codestream = j.get_codestream()
+
+        # The ssiz attribute was simply a tuple of raw bytes.
+        # The first 7 bits are interpreted as the bitdepth, the MSB determines
+        # whether or not it is signed.
+        self.assertEqual(codestream.segment[1].ssiz, (131,))
+
+
 class TestCodestreamRepr(unittest.TestCase):
 
     def setUp(self):