Merge pull request #885 from wiredfool/tiff-seek-rebase

Fix for reading multipage TIFFs

PIL/TiffImagePlugin.py

@@ -281,6 +281,7 @@ class ImageFileDirectory(collections.MutableMapping):
         self.tagdata = {}
         self.tagtype = {}  # added 2008-06-05 by Florian Hoech
         self.next = None
+        self.offset = None
 
     def __str__(self):
         return str(self.as_dict())
@@ -415,6 +416,7 @@ class ImageFileDirectory(collections.MutableMapping):
         # load tag dictionary
 
         self.reset()
+        self.offset = fp.tell()
 
         i16 = self.i16
         i32 = self.i32
@@ -446,7 +448,11 @@ class ImageFileDirectory(collections.MutableMapping):
             # Get and expand tag value
             if size > 4:
                 here = fp.tell()
+                if Image.DEBUG:
+                    print ("Tag Location: %s" %here)
                 fp.seek(i32(ifd, 8))
+                if Image.DEBUG:
+                    print ("Data Location: %s" %fp.tell())
                 data = ImageFile._safe_read(fp, size)
                 fp.seek(here)
             else:
@@ -630,18 +636,20 @@ class TiffImageFile(ImageFile.ImageFile):
 
     def seek(self, frame):
         "Select a given frame as current image"
-
         if frame < 0:
             frame = 0
         self._seek(frame)
+        # Create a new core image object on second and
+        # subsequent frames in the image. Image may be
+        # different size/mode.
+        Image._decompression_bomb_check(self.size)
+        self.im = Image.core.new(self.mode, self.size)
 
     def tell(self):
         "Return the current frame number"
-
         return self._tell()
 
     def _seek(self, frame):
-
         self.fp = self.__fp
         if frame < self.__frame:
             # rewind file
@@ -650,14 +658,21 @@ class TiffImageFile(ImageFile.ImageFile):
         while self.__frame < frame:
             if not self.__next:
                 raise EOFError("no more images in TIFF file")
+            if Image.DEBUG:
+                print("Seeking to frame %s, on frame %s, __next %s, location: %s"%
+                      (frame, self.__frame, self.__next, self.fp.tell()))            
+            # reset python3 buffered io handle in case fp
+            # was passed to libtiff, invalidating the buffer
+            self.fp.tell()
             self.fp.seek(self.__next)
+            if Image.DEBUG:
+                print("Loading tags, location: %s"%self.fp.tell())
             self.tag.load(self.fp)
             self.__next = self.tag.next
             self.__frame += 1
         self._setup()
-
+        
     def _tell(self):
-
         return self.__frame
 
     def _decoder(self, rawmode, layer, tile=None):
@@ -706,6 +721,7 @@ class TiffImageFile(ImageFile.ImageFile):
         # (self._compression, (extents tuple),
         #   0, (rawmode, self._compression, fp))
         ignored, extents, ignored_2, args = self.tile[0]
+        args = args + (self.ifd.offset,)
         decoder = Image._getdecoder(self.mode, 'libtiff', args,
                                     self.decoderconfig)
         try:
@@ -744,7 +760,8 @@ class TiffImageFile(ImageFile.ImageFile):
         self.readonly = 0
         # libtiff closed the fp in a, we need to close self.fp, if possible
         if hasattr(self.fp, 'close'):
-            self.fp.close()
+            if not self.__next:
+                self.fp.close()
         self.fp = None  # might be shared
 
         if err < 0:

Tests/test_file_libtiff.py

@@ -312,6 +312,35 @@ class TestFileLibTiff(LibTiffTestCase):
         self.assertRaises(OSError, lambda: os.fstat(fn))
         self.assertRaises(OSError, lambda: os.close(fn))
 
+    def test_multipage(self):
+        # issue #862
+        TiffImagePlugin.READ_LIBTIFF = True
+        im = Image.open('Tests/images/multipage.tiff')
+        # file is a multipage tiff,  10x10 green, 10x10 red, 20x20 blue
+
+        im.seek(0)
+        self.assertEqual(im.size, (10,10))
+        self.assertEqual(im.convert('RGB').getpixel((0,0)), (0,128,0))
+        self.assertTrue(im.tag.next)
+
+        im.seek(1)
+        self.assertEqual(im.size, (10,10))
+        self.assertEqual(im.convert('RGB').getpixel((0,0)), (255,0,0))
+        self.assertTrue(im.tag.next)
+
+        im.seek(2)
+        self.assertFalse(im.tag.next)
+        self.assertEqual(im.size, (20,20))
+        self.assertEqual(im.convert('RGB').getpixel((0,0)), (0,0,255))
+   
+        TiffImagePlugin.READ_LIBTIFF = False
+
+    def test__next(self):
+        TiffImagePlugin.READ_LIBTIFF = True
+        im = Image.open('Tests/images/lena.tif')
+        self.assertFalse(im.tag.next)
+        im.load()
+        self.assertFalse(im.tag.next)
 
 if __name__ == '__main__':
     unittest.main()

Tests/test_file_tiff.py

@@ -1,6 +1,6 @@
 from helper import unittest, PillowTestCase, lena, py3
 
-from PIL import Image
+from PIL import Image, TiffImagePlugin
 
 
 class TestFileTiff(PillowTestCase):
@@ -141,6 +141,32 @@ class TestFileTiff(PillowTestCase):
         self.assertEqual(
             im.getextrema(), (-3.140936851501465, 3.140684127807617))
 
+    def test_multipage(self):
+        # issue #862
+        im = Image.open('Tests/images/multipage.tiff')
+        # file is a multipage tiff,  10x10 green, 10x10 red, 20x20 blue
+
+        im.seek(0)
+        self.assertEqual(im.size, (10,10))
+        self.assertEqual(im.convert('RGB').getpixel((0,0)), (0,128,0))
+
+        im.seek(1)
+        im.load()
+        self.assertEqual(im.size, (10,10))
+        self.assertEqual(im.convert('RGB').getpixel((0,0)), (255,0,0))
+
+        im.seek(2)
+        im.load()
+        self.assertEqual(im.size, (20,20))
+        self.assertEqual(im.convert('RGB').getpixel((0,0)), (0,0,255))      
+
+    def test_multipage_last_frame(self):
+        im = Image.open('Tests/images/multipage-lastframe.tif')
+        im.load()
+        self.assertEqual(im.size, (20,20))
+        self.assertEqual(im.convert('RGB').getpixel((0,0)), (0,0,255))      
+        
+
     def test___str__(self):
         # Arrange
         file = "Tests/images/pil136.tiff"

Tests/test_imagesequence.py

@@ -1,6 +1,6 @@
 from helper import unittest, PillowTestCase, lena
 
-from PIL import ImageSequence
+from PIL import Image, ImageSequence, TiffImagePlugin
 
 
 class TestImageSequence(PillowTestCase):
@@ -22,7 +22,31 @@ class TestImageSequence(PillowTestCase):
 
         self.assertEqual(index, 1)
 
+    def _test_multipage_tiff(self, dbg=False):
+        # debug had side effect of calling fp.tell.
+        Image.DEBUG=dbg
+        im = Image.open('Tests/images/multipage.tiff')
+        for index, frame in enumerate(ImageSequence.Iterator(im)):
+            frame.load()
+            self.assertEqual(index, im.tell())
+            frame.convert('RGB')
+        Image.DEBUG=False
+            
+    def test_tiff(self):
+        #self._test_multipage_tiff(True)
+        self._test_multipage_tiff(False)
 
+    def test_libtiff(self):
+        codecs = dir(Image.core)
+        
+        if "libtiff_encoder" not in codecs or "libtiff_decoder" not in codecs:
+            self.skipTest("tiff support not available")
+
+        TiffImagePlugin.READ_LIBTIFF = True
+        #self._test_multipage_tiff(True)
+        self._test_multipage_tiff(False)
+        TiffImagePlugin.READ_LIBTIFF = False
+        
 if __name__ == '__main__':
     unittest.main()
 

decode.c

@@ -442,8 +442,9 @@ PyImaging_LibTiffDecoderNew(PyObject* self, PyObject* args)
     char* rawmode;
     char* compname;
     int fp;
+    int ifdoffset;
 
-    if (! PyArg_ParseTuple(args, "sssi", &mode, &rawmode, &compname, &fp))
+    if (! PyArg_ParseTuple(args, "sssii", &mode, &rawmode, &compname, &fp, &ifdoffset))
         return NULL;
 
     TRACE(("new tiff decoder %s\n", compname));
@@ -455,7 +456,7 @@ PyImaging_LibTiffDecoderNew(PyObject* self, PyObject* args)
     if (get_unpacker(decoder, mode, rawmode) < 0)
         return NULL;
 
-    if (! ImagingLibTiffInit(&decoder->state, fp)) {
+    if (! ImagingLibTiffInit(&decoder->state, fp, ifdoffset)) {
         Py_DECREF(decoder);
         PyErr_SetString(PyExc_RuntimeError, "tiff codec initialization failed");
         return NULL;

libImaging/TiffDecode.c

@@ -21,8 +21,8 @@
 #include "TiffDecode.h"
 
 void dump_state(const TIFFSTATE *state){
-	TRACE(("State: Location %u size %d eof %d data: %p \n", (uint)state->loc,
+	TRACE(("State: Location %u size %d eof %d data: %p ifd: %d\n", (uint)state->loc,
-		   (int)state->size, (uint)state->eof, state->data));
+		   (int)state->size, (uint)state->eof, state->data, state->ifd));
 }
 
 /*
@@ -142,7 +142,7 @@ void _tiffUnmapProc(thandle_t hdata, tdata_t base, toff_t size) {
 	(void) hdata; (void) base; (void) size;
 }
 
-int ImagingLibTiffInit(ImagingCodecState state, int fp) {
+int ImagingLibTiffInit(ImagingCodecState state, int fp, int offset) {
 	TIFFSTATE *clientstate = (TIFFSTATE *)state->context;
 
     TRACE(("initing libtiff\n"));
@@ -158,6 +158,7 @@ int ImagingLibTiffInit(ImagingCodecState state, int fp) {
 	clientstate->size = 0;
 	clientstate->data = 0;
 	clientstate->fp = fp;
+    clientstate->ifd = offset;
 	clientstate->eof = 0;
 
     return 1;
@@ -195,7 +196,6 @@ int ImagingLibTiffDecode(Imaging im, ImagingCodecState state, UINT8* buffer, int
 	clientstate->loc = 0;
 	clientstate->data = (tdata_t)buffer;
 	clientstate->flrealloc = 0;
-
 	dump_state(clientstate);
 
     TIFFSetWarningHandler(NULL);
@@ -220,6 +220,16 @@ int ImagingLibTiffDecode(Imaging im, ImagingCodecState state, UINT8* buffer, int
 		return -1;
 	}
 
+    if (clientstate->ifd){
+        unsigned int ifdoffset = clientstate->ifd;
+		TRACE(("reading tiff ifd %d\n", ifdoffset));
+		int rv = TIFFSetSubDirectory(tiff, ifdoffset);
+		if (!rv){
+			TRACE(("error in TIFFSetSubDirectory"));
+			return -1;
+		}
+	}
+
 	size = TIFFScanlineSize(tiff);
 	TRACE(("ScanlineSize: %d \n", size));
 	if (size > state->bytes) {

libImaging/TiffDecode.h

@@ -26,6 +26,7 @@ typedef struct {
 	toff_t loc;   /* toff_t == uint32 */
 	tsize_t size; /* tsize_t == int32 */
 	int fp;
+    int ifd; /* offset of the ifd, used for multipage */
 	TIFF *tiff; /* Used in write */
 	toff_t eof;
 	int flrealloc; /* may we realloc */
@@ -33,7 +34,7 @@ typedef struct {
 
 
 
-extern int ImagingLibTiffInit(ImagingCodecState state, int fp);
+extern int ImagingLibTiffInit(ImagingCodecState state, int fp, int offset);
 extern int ImagingLibTiffEncodeInit(ImagingCodecState state, char *filename, int fp);
 extern int ImagingLibTiffSetField(ImagingCodecState state, ttag_t tag, ...);
 
@@ -50,5 +51,4 @@ extern int ImagingLibTiffSetField(ImagingCodecState state, ttag_t tag, ...);
 
 #define TRACE(args)
 
-
 #endif