Libtiff metadata writing fixes

PIL/TiffImagePlugin.py

@@ -549,7 +549,11 @@ def _setitem(self, tag, value, legacy_api):
         if info.length == 1:
             if legacy_api and self.tagtype[tag] in [5, 10]:
                 values = values,
-            dest[tag], = values
+            try:
+                dest[tag], = values
+            except ValueError:
+                # there's a mismatch between the spec and the item from the file.
+                dest[tag] = values
         else:
             dest[tag] = values
 
@@ -666,11 +670,22 @@ def load(self, fp):
         try:
             for i in range(self._unpack("H", self._ensure_read(fp, 2))[0]):
                 tag, typ, count, data = self._unpack("HHL4s", self._ensure_read(fp, 12))
+                taginfo = TiffTags.lookup(tag)
                 if DEBUG:
-                    tagname = TiffTags.lookup(tag).name
                     typname = TYPES.get(typ, "unknown")
-                    print("tag: %s (%d) - type: %s (%d)" %
-                          (tagname, tag, typname, typ), end=" ")
+                    print("tag: %s (%d) - type: %s (%d) - spec type: %s - count: %d, spec ct: %d" %
+                          (taginfo.name, tag, typname, typ,
+                           taginfo.type, count, taginfo.length), end=" ")
+
+                if (taginfo.type and typ != taginfo.type):
+                    warnings.warn(("Possibly corrupt EXIF data.  " + 
+                                   "File tag type %s does not match spec %s for tag %s"
+                                   ) % (typ, taginfo.type, tag))
+
+                if (taginfo.length and count != taginfo.length):
+                    warnings.warn(("Possibly corrupt EXIF data.  " + 
+                                   "File tag count %s does not match spec %s for tag %s"
+                                   ) % (count, taginfo.length, tag))
 
                 try:
                     unit_size, handler = self._load_dispatch[typ]
@@ -1134,6 +1149,8 @@ def _setup(self):
             print("- size:", self.size)
 
         sampleFormat = self.tag_v2.get(SAMPLEFORMAT, (1,))
+        if not isinstance(sampleFormat, tuple):
+            sampleFormat = (sampleFormat,)
         if (len(sampleFormat) > 1
             and max(sampleFormat) == min(sampleFormat) == 1):
             # SAMPLEFORMAT is properly per band, so an RGB image will
@@ -1430,14 +1447,26 @@ def _save(im, fp, filename):
         # based on the data in the strip.
         blocklist = [STRIPOFFSETS, STRIPBYTECOUNTS]
         atts = {}
+        # atts is a dict of key: tuple(type, array, count, value)
+        # where type is the tifftype int
+        # array is 0/1 for single or array value
+        # count is the number of items
+        # value is the value, or a tuple of the items.
+        # Note that we've got some items where there's an unspecified length
+        # in the spec (or 0), and they may have 1 item, so they need to be
+        # passed in in the array interface as an array of one item.
+
         # bits per sample is a single short in the tiff directory, not a list.
-        atts[BITSPERSAMPLE] = bits[0]
+        tag_info = TiffTags.lookup(BITSPERSAMPLE)
+        atts[BITSPERSAMPLE] = (tag_info.type, 0, 1, bits[0])
         # Merge the ones that we have with (optional) more bits from
         # the original file, e.g x,y resolution so that we can
         # save(load('')) == original file.
         legacy_ifd = {}
         if hasattr(im, 'tag'):
             legacy_ifd = im.tag.to_v2()
+            if DEBUG:
+                print("Legacy IFD items: %s" % sorted(legacy_ifd.items()))
         for tag, value in itertools.chain(ifd.items(),
                                           getattr(im, 'tag_v2', {}).items(),
                                           legacy_ifd.items()):
@@ -1448,16 +1477,38 @@ def _save(im, fp, filename):
             # UNDONE --  add code for the custom dictionary
             if tag not in TiffTags.LIBTIFF_CORE:
                 continue
-            if tag not in atts and tag not in blocklist:
-                if isinstance(value, unicode if bytes is str else str):
-                    atts[tag] = value.encode('ascii', 'replace') + b"\0"
-                elif isinstance(value, IFDRational):
-                    atts[tag] = float(value)
-                else:
-                    atts[tag] = value
+            if tag in atts:
+                continue
+            if tag in blocklist:
+                continue
+            tag_info = TiffTags.lookup(tag)
+            # numeric types
+            if tag_info.length == 1:
+                if tag_info.type in (3,4,6,8,9):
+                    atts[tag] = (tag_info.type, 0, 1, int(value))
+                elif tag_info.type in (5,10,11,12):
+                    atts[tag] = (tag_info.type, 0, 1, float(value))
+                elif tag_info.type == 2:
+                    if isinstance(value, unicode if bytes is str else str):
+                        atts[tag] = (tag_info.type, 0, 1,
+                                     value.encode('ascii', 'replace') + b"\0")
+                    else:
+                        atts[tag] = (tag_info.type, 0, 1, value)
+                # we're not sending bytes to libtiff, as they require custom fields.
+                #elif tag_info.type == 7:
+                #    atts[tag] = (tag_info.type, 0, 1, value)
+
+            else: # undefined or set length. 
+                if tag_info.type in (3,4,6,8,9):
+                    atts[tag] = (tag_info.type, 1, len(value), tuple(map(int,value)))
+                elif tag_info.type in (5,10,11,12):
+                    atts[tag] = (tag_info.type, 1, len(value), tuple(map(float,value)))
+            # stringish types    
+
 
         if DEBUG:
             print("Converted items: %s" % sorted(atts.items()))
+            print("Length: %s" % len(atts))
 
         # libtiff always expects the bytes in native order.
         # we're storing image byte order. So, if the rawmode

PIL/TiffTags.py

@@ -95,8 +95,8 @@ def lookup(tag):
     278: ("RowsPerStrip", LONG, 1),
     279: ("StripByteCounts", LONG, 0),
 
-    280: ("MinSampleValue", LONG, 0),
-    281: ("MaxSampleValue", SHORT, 0),
+    280: ("MinSampleValue", LONG, 1),
+    281: ("MaxSampleValue", SHORT, 1),
     282: ("XResolution", RATIONAL, 1),
     283: ("YResolution", RATIONAL, 1),
     284: ("PlanarConfiguration", SHORT, 1, {"Contiguous": 1, "Separate": 2}),
@@ -121,7 +121,7 @@ def lookup(tag):
     316: ("HostComputer", ASCII, 1),
     317: ("Predictor", SHORT, 1, {"none": 1, "Horizontal Differencing": 2}),
     318: ("WhitePoint", RATIONAL, 2),
-    319: ("PrimaryChromaticities", SHORT, 6),
+    319: ("PrimaryChromaticities", RATIONAL, 6),
 
     320: ("ColorMap", SHORT, 0),
     321: ("HalftoneHints", SHORT, 2),
@@ -130,16 +130,17 @@ def lookup(tag):
     324: ("TileOffsets", LONG, 0),
     325: ("TileByteCounts", LONG, 0),
 
+    330: ("SubIFD", SHORT, 1),
     332: ("InkSet", SHORT, 1),
     333: ("InkNames", ASCII, 1),
     334: ("NumberOfInks", SHORT, 1),
     336: ("DotRange", SHORT, 0),
     337: ("TargetPrinter", ASCII, 1),
     338: ("ExtraSamples", SHORT, 0),
-    339: ("SampleFormat", SHORT, 0),
+    339: ("SampleFormat", SHORT, 1),
 
-    340: ("SMinSampleValue", DOUBLE, 0),
-    341: ("SMaxSampleValue", DOUBLE, 0),
+    340: ("SMinSampleValue", DOUBLE, 1),
+    341: ("SMaxSampleValue", DOUBLE, 1),
     342: ("TransferRange", SHORT, 6),
 
     # obsolete JPEG tags
@@ -156,7 +157,13 @@ def lookup(tag):
     529: ("YCbCrCoefficients", RATIONAL, 3),
     530: ("YCbCrSubSampling", SHORT, 2),
     531: ("YCbCrPositioning", SHORT, 1),
-    532: ("ReferenceBlackWhite", LONG, 0),
+    532: ("ReferenceBlackWhite", RATIONAL, 6),
+
+    # sgi, in core
+    32995:("Matteing", SHORT, 1),
+    32996:("DataType", SHORT, 1),
+    32997:("ImageDepth", LONG, 1),
+    32998:("TileDepth", LONG, 1),
 
     33432: ("Copyright", ASCII, 1),
 
@@ -417,23 +424,25 @@ def _populate():
 # 393:	case TIFFTAG_INKNAMES:
 
 # some of these are not in our TAGS_V2 dict and were included from tiff.h
+# Anything included here needs to have the correct type in TAGS_V2 above
 
 LIBTIFF_CORE = {255, 256, 257, 258, 259, 262, 263, 266, 274, 277,
                 278, 280, 281, 340, 341, 282, 283, 284, 286, 287,
                 296, 297, 321, 320, 338, 32995, 322, 323, 32998,
                 32996, 339, 32997, 330, 531, 530, 301, 532, 333,
                 # as above
-                269  # this has been in our tests forever, and works
+                269,  # this has been in our tests forever, and works
+                318, # Whitepoint, Specific test for it
+                319, # Primary Chromaticities
                 }
 
-LIBTIFF_CORE.remove(320)  # Array of short, crashes
-LIBTIFF_CORE.remove(301)  # Array of short, crashes
-LIBTIFF_CORE.remove(532)  # Array of long, crashes
+LIBTIFF_CORE.remove(330)  # subifd, requires extra support for uint64 payload
 
 LIBTIFF_CORE.remove(255)  # We don't have support for subfiletypes
 LIBTIFF_CORE.remove(322)  # We don't have support for tiled images in libtiff
 LIBTIFF_CORE.remove(323)  # Tiled images
 LIBTIFF_CORE.remove(333)  # Ink Names either
+LIBTIFF_CORE.remove(301)  # Transfer Function. No support as of yet.
 
 # Note to advanced users: There may be combinations of these
 # parameters and values that when added properly, will work and

Tests/test_file_libtiff.py

@@ -194,6 +194,7 @@ def test_additional_metadata(self):
                 del(core_items[tag])
             except:
                 pass
+        del(core_items[320])  # colormap is special, tested below
 
         # Type codes:
         #     2: "ascii",
@@ -222,11 +223,21 @@ def test_additional_metadata(self):
 
         out = self.tempfile("temp.tif")
         TiffImagePlugin.WRITE_LIBTIFF = True
-
+        
         im.save(out, tiffinfo=new_ifd)
 
         TiffImagePlugin.WRITE_LIBTIFF = False
 
+    def test_int_dpi(self):
+        # issue #1765
+        im = hopper('RGB')
+        out = self.tempfile('temp.tif')
+        TiffImagePlugin.WRITE_LIBTIFF = True
+        im.save(out, dpi=(72, 72))
+        TiffImagePlugin.WRITE_LIBTIFF = False
+        reloaded = Image.open(out)
+        self.assertEqual(reloaded.info['dpi'], (72.0, 72.0))
+
     def test_g3_compression(self):
         i = Image.open('Tests/images/hopper_g4_500.tif')
         out = self.tempfile("temp.tif")
@@ -354,6 +365,19 @@ def test_cmyk_save(self):
         im2 = Image.open(out)
         self.assert_image_equal(im, im2)
 
+    def test_palette_save(self):
+        im = hopper('P')
+        out = self.tempfile('temp.tif')
+        TiffImagePlugin.WRITE_LIBTIFF = True
+        im.save(out)
+        TiffImagePlugin.WRITE_LIBTIFF = False
+
+        reloaded = Image.open(out)
+        # colormap/palette tag
+        self.assertTrue(len(reloaded.tag_v2[320]), 768)
+        self.assert_image_equal(im, reloaded)
+
+
     def xtest_bw_compression_w_rgb(self):
         """ This test passes, but when running all tests causes a failure due
             to output on stderr from the error thrown by libtiff. We need to
@@ -493,6 +517,16 @@ def test_crashing_metadata(self):
         im.save(out, format='TIFF')
         TiffImagePlugin.WRITE_LIBTIFF = False
 
+        reloaded = Image.open(out)
+
+        self.assert_image_equal(im, reloaded)
+        for tag in (318, 319):
+            for ix in range(len(im.tag_v2[tag])):
+                self.assertAlmostEqual(float(im.tag_v2[tag][ix]),
+                                       float(reloaded.tag_v2[tag][ix]),
+                                       places=5)
+
+
     def test_page_number_x_0(self):
         # Issue 973
         # Test TIFF with tag 297 (Page Number) having value of 0 0.

docs/reference/internal_design.rst

@@ -6,3 +6,5 @@ Internal Reference Docs
 
   open_files
   limits
+  tiff_metadata
+