Success with default conversion from j2c to jp2.

glymur/jp2box.py

@@ -167,7 +167,7 @@ class ColourSpecificationBox(Jp2kBox):
         colorspace is not None, then icc_profile must be empty.
     """
     def __init__(self, method=ENUMERATED_COLORSPACE, precedence=0,
-                 approximation=1, colorspace=None, icc_profile=None, **kwargs):
+                 approximation=0, colorspace=None, icc_profile=None, **kwargs):
         Jp2kBox.__init__(self, id='', longname='Colour Specification')
 
         if colorspace is not None and icc_profile is not None:
@@ -208,6 +208,20 @@ class ColourSpecificationBox(Jp2kBox):
 
         return msg
 
+    def _write(self, f):
+        """Write an Colour Specification box to file.
+        """
+        length = 15 if self.icc_profile is None else 11 + len(self.icc_profile)
+        f.write(struct.pack('>I', length)) 
+        f.write('colr'.encode())
+
+        buffer = struct.pack('>BBBI',
+                             self.method,
+                             self.precedence,
+                             self.approximation,
+                             self.colorspace)
+        f.write(buffer)
+
     @staticmethod
     def _parse(f, id, offset, length):
         """Parse JPEG 2000 color specification box.
@@ -756,6 +770,25 @@ class ImageHeaderBox(Jp2kBox):
                          self.colorspace_unknown)
         return msg
 
+    def _write(self, f):
+        """Write an Image Header box to file.
+        """
+        f.write(struct.pack('>I', 22)) 
+        f.write('ihdr'.encode())
+
+        # signedness and bps are stored together in a single byte
+        bit_depth_signedness = 0x80 if self.signed else 0x00
+        bit_depth_signedness |= self.bits_per_component - 1 
+        buffer = struct.pack('>IIHBBBB',
+                             self.height,
+                             self.width,
+                             self.num_components,
+                             bit_depth_signedness,
+                             self.compression,
+                             1 if self.colorspace_unknown else 0,
+                             1 if self.ip_provided else 0)
+        f.write(buffer)
+
     @staticmethod
     def _parse(f, id, offset, length):
         """Parse JPEG 2000 image header box.

glymur/jp2k.py

@@ -407,17 +407,37 @@ class Jp2k(Jp2kBox):
         filename : str
            JP2 file to be created from a raw codestream.
         """
+        if len(self.box) > 0:
+            msg = "This method  can only be used on files consisting only of "
+            msg += "a raw codestream.  It cannot be used on a file that "
+            msg += "already has the JP2 format."
+            raise IOError(msg)
+
         boxes = [JPEG2000SignatureBox(),
                  FileTypeBox(),
-                 JP2HeaderBox(),
+                 JP2HeaderBox()]
-                 ContiguousCodestreamBox()]
+        c = self.get_codestream()
-        boxes[2].box = [ImageHeaderBox(height=1456,
+        height = c.segment[1].Ysiz
-                                       width=2592,
+        width = c.segment[1].Xsiz
-                                       num_components=3),
+        num_components = len(c.segment[1].XRsiz)
+        boxes[2].box = [ImageHeaderBox(height=height,
+                                       width=width,
+                                       num_components=num_components),
                         ColourSpecificationBox(colorspace=SRGB)]
-        with open(filename, 'wb') as fp:
+        with open(filename, 'wb') as ofile:
             for box in boxes:
-                box._write(fp)
+                box._write(ofile)
+
+            # The codestream gets written last.
+            ofile.write(struct.pack('>I', self.length + 8))
+            ofile.write('jp2c'.encode())
+
+            with open(self.filename, 'rb') as ifile:
+                ofile.write(ifile.read())
+
+            ofile.flush()
+
+
 
     def read(self, reduce=0, layer=0, area=None, tile=None, verbose=False):
         """Read a JPEG 2000 image.

glymur/test/test_jp2box.py

@@ -28,7 +28,7 @@ class TestJp2Boxes(unittest.TestCase):
         j = Jp2k(jp2file)
         c = [box for box in j.box if box.id == 'jp2c'][0]
 
-        with tempfile.NamedTemporaryFile(suffix='.jp2', delete=False) as ofile:
+        with tempfile.NamedTemporaryFile(suffix='.j2c', delete=False) as ofile:
             with open(jp2file, 'rb') as ifile:
                 # Everything up until the jp2c box.
                 ifile.seek(c.offset+8)
@@ -74,7 +74,7 @@ class TestJp2Boxes(unittest.TestCase):
         b = glymur.jp2box.ColourSpecificationBox(colorspace=glymur.core.SRGB)
         self.assertEqual(b.method,  glymur.core.ENUMERATED_COLORSPACE)
         self.assertEqual(b.precedence, 0)
-        self.assertEqual(b.approximation, 1)
+        self.assertEqual(b.approximation, 0)
         self.assertEqual(b.colorspace, glymur.core.SRGB)
         self.assertIsNone(b.icc_profile)
 
@@ -108,9 +108,71 @@ class TestJp2Boxes(unittest.TestCase):
         self.assertEqual(b.main_header, [])
 
     def test_tojp2(self):
-        j = Jp2k(self.raw_codestream)
+        j2k = Jp2k(self.raw_codestream)
+        with tempfile.NamedTemporaryFile(suffix=".jp2", mode="wb") as tfile:
+            j2k.tojp2(tfile.name)
+            
+            jp2 = Jp2k(tfile.name) 
+            self.assertEqual(len(jp2.box), 4)
+    
+            self.assertEqual(jp2.box[0].id, 'jP  ')
+            self.assertEqual(jp2.box[0].offset, 0)
+            self.assertEqual(jp2.box[0].length, 12)
+            self.assertEqual(jp2.box[0].longname, 'JPEG 2000 Signature')
+    
+            self.assertEqual(jp2.box[1].id, 'ftyp')
+            self.assertEqual(jp2.box[1].offset, 12)
+            self.assertEqual(jp2.box[1].length, 20)
+            self.assertEqual(jp2.box[1].longname, 'File Type')
+    
+            self.assertEqual(jp2.box[2].id, 'jp2h')
+            self.assertEqual(jp2.box[2].offset, 32)
+            self.assertEqual(jp2.box[2].length, 45)
+            self.assertEqual(jp2.box[2].longname, 'JP2 Header')
+    
+            self.assertEqual(jp2.box[3].id, 'jp2c')
+            self.assertEqual(jp2.box[3].offset, 77)
+            self.assertEqual(jp2.box[3].length, 1133427)
+    
+            # jp2h super box
+            self.assertEqual(len(jp2.box[2].box), 2)
+    
+            self.assertEqual(jp2.box[2].box[0].id, 'ihdr')
+            self.assertEqual(jp2.box[2].box[0].offset, 40)
+            self.assertEqual(jp2.box[2].box[0].length, 22)
+            self.assertEqual(jp2.box[2].box[0].longname, 'Image Header')
+            self.assertEqual(jp2.box[2].box[0].height, 1456)
+            self.assertEqual(jp2.box[2].box[0].width, 2592)
+            self.assertEqual(jp2.box[2].box[0].num_components, 3)
+            self.assertEqual(jp2.box[2].box[0].bits_per_component, 8)
+            self.assertEqual(jp2.box[2].box[0].signed, False)
+            self.assertEqual(jp2.box[2].box[0].compression, 7)
+            self.assertEqual(jp2.box[2].box[0].colorspace_unknown, False)
+            self.assertEqual(jp2.box[2].box[0].ip_provided, False)
+    
+            self.assertEqual(jp2.box[2].box[1].id, 'colr')
+            self.assertEqual(jp2.box[2].box[1].offset, 62)
+            self.assertEqual(jp2.box[2].box[1].length, 15)
+            self.assertEqual(jp2.box[2].box[1].longname, 'Colour Specification')
+            self.assertEqual(jp2.box[2].box[1].precedence, 0)
+            self.assertEqual(jp2.box[2].box[1].approximation, 0)
+            self.assertEqual(jp2.box[2].box[1].colorspace, glymur.core.SRGB)
+            self.assertIsNone(jp2.box[2].box[1].icc_profile)
+
+    def test_image_header_box_not_first_in_jp2_header(self):
+        # The specification says that ihdr must be the first box in jp2h.
+        self.assertTrue(False)
+
+    def test_color_specification_box_with_icc_profile(self):
+        # Not sure how this should be done so don't allow it.
+        self.assertTrue(False)
+
+    def test_tojp2_on_jp2(self):
+        # Should not use "tojp2" method on file that is already jp2.
+        j = glymur.Jp2k(self.jp2file)
         with tempfile.NamedTemporaryFile(suffix=".jp2") as tfile:
-            j.tojp2(tfile.name)
+            with self.assertRaises(IOError):
+                j.tojp2(tfile.name)
 
 if __name__ == "__main__":
     unittest.main()