Closes #62

glymur/jp2k.py

@@ -431,6 +431,15 @@ class Jp2k(Jp2kBox):
             msg += "must be the file type box."
             raise IOError(msg)
 
+        # jp2c must be preceeded by jp2h
+        jp2h_lst = [idx for (idx, box) in enumerate(boxes) if box.id == 'jp2h']
+        jp2h_idx = jp2h_lst[0]
+        jp2c_lst = [idx for (idx, box) in enumerate(boxes) if box.id == 'jp2c']
+        jp2c_idx = jp2c_lst[0]
+        if jp2h_idx >= jp2c_idx:
+            msg = "The codestream box must be preceeded by a jp2 header box."
+            raise IOError(msg)
+
         with open(filename, 'wb') as ofile:
             for box in boxes:
                 if box.id != 'jp2c':

glymur/test/test_jp2box.py

@@ -289,6 +289,26 @@ class TestJp2Boxes(unittest.TestCase):
             with self.assertRaises(IOError):
                 j2k.wrap(tfile.name, boxes=boxes)
 
+    def test_jp2h_not_preceeding_jp2c(self):
+        j2k = Jp2k(self.raw_codestream)
+        c = j2k.get_codestream()
+        height = c.segment[1].Ysiz
+        width = c.segment[1].Xsiz
+        num_components = len(c.segment[1].XRsiz)
+
+        jP = JPEG2000SignatureBox()
+        ftyp = FileTypeBox()
+        jp2h = JP2HeaderBox()
+        jp2c = ContiguousCodestreamBox()
+        colr = ColourSpecificationBox(colorspace=glymur.core.SRGB)
+        ihdr = ImageHeaderBox(height=height, width=width,
+                              num_components=num_components)
+        jp2h.box = [ihdr, colr]
+        boxes = [jP, ftyp, jp2c, jp2h]
+        with tempfile.NamedTemporaryFile(suffix=".jp2") as tfile:
+            #with self.assertRaises(IOError):
+            j2k.wrap(tfile.name, boxes=boxes)
+
 
 if __name__ == "__main__":
     unittest.main()