Added possibility of creating XMLBox by reading an XML file.

glymur/jp2box.py

@@ -1537,8 +1537,24 @@ class XMLBox(Jp2kBox):
     xml : ElementTree.Element
         XML section.
     """
-    def __init__(self, **kwargs):
+    def __init__(self, xml=None, filename=None, **kwargs):
+        """
+        Parameters
+        ----------
+        xml : ElementTree
+            An ElementTree object already existing in python.
+        filename : str
+            File from which to read XML.  If filename is not None, then the xml
+            keyword argument must be None.
+        """
         Jp2kBox.__init__(self, id='xml ', longname='XML')
+        if filename is not None and xml is not None:
+            msg = "Only one of either filename or xml should be provided."
+            raise IOError(msg)
+        if filename is not None:
+            self.xml = ET.parse(filename)
+        else:
+            self.xml = xml
         self.__dict__.update(**kwargs)
 
     def __str__(self):
@@ -1553,7 +1569,11 @@ class XMLBox(Jp2kBox):
     def _write(self, f):
         """Write an XML box to file.
         """
-        buffer = ET.tostring(self.xml, encoding='utf-8')
+        try:
+            buffer = ET.tostring(self.xml, encoding='utf-8')
+        except AttributeError:
+            buffer = ET.tostring(self.xml.getroot(), encoding='utf-8')
+
         f.write(struct.pack('>I', len(buffer) + 8))
         f.write(self.id.encode())
         f.write(buffer)

glymur/test/test_jp2box.py

@@ -371,6 +371,60 @@ class TestJp2Boxes(unittest.TestCase):
             jp2 = Jp2k(tfile.name)
             self.assertEqual(jp2.box[3].id, 'xml ')
 
+    def test_xml_from_file(self):
+        raw_xml = b"""<?xml version="1.0"?>
+        <data>
+            <country name="Liechtenstein">
+                <rank>1</rank>
+                <year>2008</year>
+                <gdppc>141100</gdppc>
+                <neighbor name="Austria" direction="E"/>
+                <neighbor name="Switzerland" direction="W"/>
+            </country>
+            <country name="Singapore">
+                <rank>4</rank>
+                <year>2011</year>
+                <gdppc>59900</gdppc>
+                <neighbor name="Malaysia" direction="N"/>
+            </country>
+            <country name="Panama">
+                <rank>68</rank>
+                <year>2011</year>
+                <gdppc>13600</gdppc>
+                <neighbor name="Costa Rica" direction="W"/>
+                <neighbor name="Colombia" direction="E"/>
+            </country>
+        </data>"""
+        with tempfile.NamedTemporaryFile(suffix=".xml") as tfile:
+            tfile.write(raw_xml)                
+            tfile.flush()
+
+            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()
+            ihdr = ImageHeaderBox(height=height, width=width,
+                                  num_components=num_components)
+            colr = ColourSpecificationBox(colorspace=glymur.core.SRGB)
+            jp2h.box = [ihdr, colr]
+    
+            xmlb = glymur.jp2box.XMLBox(filename=tfile.name)
+            boxes = [jP, ftyp, jp2h, xmlb, jp2c]
+            with tempfile.NamedTemporaryFile(suffix=".jp2") as tfile:
+                j2k.wrap(tfile.name, boxes=boxes)
+                jp2 = Jp2k(tfile.name)
+
+                output_boxes = [box.id for box in jp2.box]
+                self.assertEqual(output_boxes, ['jP  ', 'ftyp', 'jp2h', 'xml ',
+                                                'jp2c'])
+                self.assertIsNotNone(jp2.box[3].xml)
+
 
 if __name__ == "__main__":
     unittest.main()