Added missing HEIC box names and handling of a TIFF header inside HEIC

exifread/__init__.py

@@ -26,6 +26,22 @@ def _find_tiff_exif(fh: BinaryIO) -> tuple:
     offset = 0
     return offset, endian
 
+def _find_heic_tiff(fh: BinaryIO) -> tuple:
+    """ In some HEIC files, the Exif offset is 0 and there is a plain TIFF header near end of the file. """
+
+    data = fh.read(4)
+    if data[0:2] in [b'II', b'MM'] and data [2] == 42 and data[3] == 0:
+        offset = fh.tell() - 4
+        fh.seek(offset)
+        endian = data[0:2]
+        offset = fh.tell()
+        logger.debug('Found TIFF header in Exif, offset = %0xH', offset)
+    else:
+        raise InvalidExif(
+            "Exif pointer to zeros, but found " + str(data) + " instead of a TIFF header."
+        )
+
+    return offset, endian
 
 def _find_webp_exif(fh: BinaryIO) -> tuple:
     logger.debug("WebP format recognized in data[0:4], data[8:12]")
@@ -108,6 +124,9 @@ def _determine_type(fh: BinaryIO) -> tuple:
         fh.seek(0)
         heic = HEICExifFinder(fh)
         offset, endian = heic.find_exif()
+        if offset == 0:
+            offset, endian = _find_heic_tiff(fh)
+            # It's a HEIC file with a TIFF header
     elif data[0:4] == b'RIFF' and data[8:12] == b'WEBP':
         offset, endian = _find_webp_exif(fh)
     elif data[0:2] == b'\xFF\xD8':

exifread/heic.py

@@ -164,6 +164,12 @@ def get_parser(self, box: Box) -> Optional[Callable[[Box], Any]]:
             'infe': self._parse_infe,
             'iinf': self._parse_iinf,
             'iloc': self._parse_iloc,
+            'hdlr': self._parse_hdlr,  # HEIC/AVIF hdlr = Handler
+            'pitm': self._parse_pitm,  # HEIC/AVIF pitm = Primary Item
+            'iref': self._parse_iref,  # HEIC/AVIF idat = Item Reference
+            'idat': self._parse_idat,  # HEIC/AVIF idat = Item Data Box
+            'dinf': self._parse_dinf,  # HEIC/AVIF dinf = Data Information Box
+            'iprp': self._parse_iprp,  # HEIC/AVIF iprp = Item Protection Box
         }
         return defs.get(box.name)
 
@@ -257,6 +263,37 @@ def _parse_iloc(self, box: Box):
                 extents.append((extent_offset, extent_length))
             box.locs[item_id] = extents
 
+    # Added a few box names, which as unhandled aborted data extraction:
+    # hdlr, pitm, dinf, iprp, idat, iref
+    #
+    # Handling is initially `None`.
+    # They were found in .heif photo files produced by Nokia 8.3 5G.
+    #
+    # They are part of the standard, referring to:
+    #   - ISO/IEC 14496-12 fifth edition 2015-02-20 (chapter 8.10 Metadata)
+    #     found in:
+    #     https://mpeg.chiariglione.org/standards/mpeg-4/iso-base-media-file-format/text-isoiec-14496-12-5th-edition
+    #     (The newest is ISO/IEC 14496-12:2022, but would cost 208 Swiss Francs at iso.org)
+    #   - A C++ example: https://exiv2.org/book/#BMFF
+
+    def _parse_hdlr(self, box: Box):
+        logger.debug("HEIC: found 'hdlr' Box %s, skipped", box.name)
+
+    def _parse_pitm(self, box: Box):
+        logger.debug("HEIC: found 'pitm' Box %s, skipped", box.name)
+
+    def _parse_dinf(self, box: Box):
+        logger.debug("HEIC: found 'dinf' Box %s, skipped", box.name)
+
+    def _parse_iprp(self, box: Box):
+        logger.debug("HEIC: found 'iprp' Box %s, skipped", box.name)
+
+    def _parse_idat(self, box: Box):
+        logger.debug("HEIC: found 'idat' Box %s, skipped", box.name)
+
+    def _parse_iref(self, box: Box):
+        logger.debug("HEIC: found 'iref' Box %s, skipped", box.name)
+
     def find_exif(self) -> tuple:
         ftyp = self.expect_parse('ftyp')
         assert ftyp.major_brand == b'heic'
@@ -277,8 +314,17 @@ def find_exif(self) -> tuple:
         # b'Exif\x00\x00' (without APP1 marker, e.g. iOS)
         # according to "ISO/IEC 23008-12, 2017-12", both of them are legal
         exif_tiff_header_offset = self.get32()
-        assert exif_tiff_header_offset >= 6
-        assert self.get(exif_tiff_header_offset)[-6:] == b'Exif\x00\x00'
-        offset = self.file_handle.tell()
-        endian = self.file_handle.read(1)
+
+        if exif_tiff_header_offset == 0:
+            # This case was found in HMD Nokia 8.3 5G heic photos.
+            # The TIFF header just sits there without any 'Exif'.
+
+            offset = 0
+            endian = '?' # Haven't got Endian info yet
+        else:
+            assert exif_tiff_header_offset >= 6
+            assert self.get(exif_tiff_header_offset)[-6:] == b'Exif\x00\x00'
+            offset = self.file_handle.tell()
+            endian = str(self.file_handle.read(1))
+
         return offset, endian