def load(self, fp):
self.reset()
self._offset = fp.tell()
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))
if DEBUG:
tagname = TAGS_V2.get(tag, TagInfo()).name
typname = TYPES.get(typ, "unknown")
print(
"tag: %s (%d) - type: %s (%d)" % (tagname, tag,
typname, typ),
end=" ")
try:
unit_size, handler = self._load_dispatch[typ]
except KeyError:
if DEBUG:
print("- unsupported type", typ)
continue # ignore unsupported type
size = count * unit_size
if size > 4:
here = fp.tell()
offset, = self._unpack("L", data)
if DEBUG:
print(
"Tag Location: %s - Data Location: %s" % (here,
offset),
end=" ")
fp.seek(offset)
data = ImageFile._safe_read(fp, size)
fp.seek(here)
else:
data = data[:size]
if len(data) != size:
warnings.warn(
"Possibly corrupt EXIF data. "
"Expecting to read %d bytes but only got %d. "
"Skipping tag %s" % (size, len(data), tag))
continue
self._tagdata[tag] = data
self.tagtype[tag] = typ
if DEBUG:
if size > 32:
print("- value: <table: %d bytes>" % size)
else:
print("- value:", self[tag])
self.next, = self._unpack("L", self._ensure_read(fp, 4))
except IOError as msg:
warnings.warn(str(msg))
return
def load(self, fp):
self.reset()
self._offset = fp.tell()
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))
if DEBUG:
tagname = TAGS_V2.get(tag, TagInfo()).name
typname = TYPES.get(typ, "unknown")
print("tag: %s (%d) - type: %s (%d)" %
(tagname, tag, typname, typ),
end=" ")
try:
unit_size, handler = self._load_dispatch[typ]
except KeyError:
if DEBUG:
print("- unsupported type", typ)
continue # ignore unsupported type
size = count * unit_size
if size > 4:
here = fp.tell()
offset, = self._unpack("L", data)
if DEBUG:
print("Tag Location: %s - Data Location: %s" %
(here, offset),
end=" ")
fp.seek(offset)
data = ImageFile._safe_read(fp, size)
fp.seek(here)
else:
data = data[:size]
if len(data) != size:
warnings.warn(
"Possibly corrupt EXIF data. "
"Expecting to read %d bytes but only got %d. "
"Skipping tag %s" % (size, len(data), tag))
continue
self._tagdata[tag] = data
self.tagtype[tag] = typ
if DEBUG:
if size > 32:
print("- value: <table: %d bytes>" % size)
else:
print("- value:", self[tag])
self.next, = self._unpack("L", self._ensure_read(fp, 4))
except IOError as msg:
warnings.warn(str(msg))
return
def save(self, fp):
if fp.tell() == 0: # skip TIFF header on subsequent pages
# tiff header -- PIL always starts the first IFD at offset 8
fp.write(self._prefix + self._pack("HL", 42, 8))
# FIXME What about tagdata?
fp.write(self._pack("H", len(self._tags_v2)))
entries = []
offset = fp.tell() + len(self._tags_v2) * 12 + 4
stripoffsets = None
# pass 1: convert tags to binary format
# always write tags in ascending order
for tag, value in sorted(self._tags_v2.items()):
if tag == STRIPOFFSETS:
stripoffsets = len(entries)
typ = self.tagtype.get(tag)
if DEBUG:
print("Tag %s, Type: %s, Value: %s" % (tag, typ, value))
values = value if isinstance(value, tuple) else (value,)
data = self._write_dispatch[typ](self, *values)
if DEBUG:
tagname = TAGS_V2.get(tag, TagInfo()).name
typname = TYPES.get(typ, "unknown")
print("save: %s (%d) - type: %s (%d)" %
(tagname, tag, typname, typ), end=" ")
if len(data) >= 16:
print("- value: <table: %d bytes>" % len(data))
else:
print("- value:", values)
# count is sum of lengths for string and arbitrary data
count = len(data) if typ in [2, 7] else len(values)
# figure out if data fits into the entry
if len(data) <= 4:
entries.append((tag, typ, count, data.ljust(4, b"\0"), b""))
else:
entries.append((tag, typ, count, self._pack("L", offset), data))
offset += (len(data) + 1) // 2 * 2 # pad to word
# update strip offset data to point beyond auxiliary data
if stripoffsets is not None:
tag, typ, count, value, data = entries[stripoffsets]
if data:
raise NotImplementedError(
"multistrip support not yet implemented")
value = self._pack("L", self._unpack("L", value)[0] + offset)
entries[stripoffsets] = tag, typ, count, value, data
# pass 2: write entries to file
for tag, typ, count, value, data in entries:
if DEBUG > 1:
print(tag, typ, count, repr(value), repr(data))
fp.write(self._pack("HHL4s", tag, typ, count, value))
# -- overwrite here for multi-page --
fp.write(b"\0\0\0\0") # end of entries
# pass 3: write auxiliary data to file
for tag, typ, count, value, data in entries:
fp.write(data)
if len(data) & 1:
fp.write(b"\0")
return offset
fp.write(self._pack("HHL4s", tag, typ, count, value))
# -- overwrite here for multi-page --
fp.write(b"\0\0\0\0") # end of entries
# pass 3: write auxiliary data to file
for tag, typ, count, value, data in entries:
fp.write(data)
if len(data) & 1:
fp.write(b"\0")
return offset
ImageFileDirectory_v2._load_dispatch = _load_dispatch
ImageFileDirectory_v2._write_dispatch = _write_dispatch
for idx, name in TYPES.items():
name = name.replace(" ", "_")
setattr(ImageFileDirectory_v2, "load_" + name, _load_dispatch[idx][1])
setattr(ImageFileDirectory_v2, "write_" + name, _write_dispatch[idx])
del _load_dispatch, _write_dispatch, idx, name
# Legacy ImageFileDirectory support.
class ImageFileDirectory_v1(ImageFileDirectory_v2):
"""This class represents the **legacy** interface to a TIFF tag directory.
Exposes a dictionary interface of the tags in the directory::
ifd = ImageFileDirectory_v1()
ifd[key] = 'Some Data'
ifd.tagtype[key] = 2
def save(self, fp):
if fp.tell() == 0: # skip TIFF header on subsequent pages
# tiff header -- PIL always starts the first IFD at offset 8
fp.write(self._prefix + self._pack("HL", 42, 8))
# FIXME What about tagdata?
fp.write(self._pack("H", len(self._tags_v2)))
entries = []
offset = fp.tell() + len(self._tags_v2) * 12 + 4
stripoffsets = None
# pass 1: convert tags to binary format
# always write tags in ascending order
for tag, value in sorted(self._tags_v2.items()):
if tag == STRIPOFFSETS:
stripoffsets = len(entries)
typ = self.tagtype.get(tag)
if DEBUG:
print("Tag %s, Type: %s, Value: %s" % (tag, typ, value))
values = value if isinstance(value, tuple) else (value, )
data = self._write_dispatch[typ](self, *values)
if DEBUG:
tagname = TAGS_V2.get(tag, TagInfo()).name
typname = TYPES.get(typ, "unknown")
print("save: %s (%d) - type: %s (%d)" %
(tagname, tag, typname, typ),
end=" ")
if len(data) >= 16:
print("- value: <table: %d bytes>" % len(data))
else:
print("- value:", values)
# count is sum of lengths for string and arbitrary data
count = len(data) if typ in [2, 7] else len(values)
# figure out if data fits into the entry
if len(data) <= 4:
entries.append((tag, typ, count, data.ljust(4, b"\0"), b""))
else:
entries.append((tag, typ, count, self._pack("L",
offset), data))
offset += (len(data) + 1) // 2 * 2 # pad to word
# update strip offset data to point beyond auxiliary data
if stripoffsets is not None:
tag, typ, count, value, data = entries[stripoffsets]
if data:
raise NotImplementedError(
"multistrip support not yet implemented")
value = self._pack("L", self._unpack("L", value)[0] + offset)
entries[stripoffsets] = tag, typ, count, value, data
# pass 2: write entries to file
for tag, typ, count, value, data in entries:
if DEBUG > 1:
print(tag, typ, count, repr(value), repr(data))
fp.write(self._pack("HHL4s", tag, typ, count, value))
# -- overwrite here for multi-page --
fp.write(b"\0\0\0\0") # end of entries
# pass 3: write auxiliary data to file
for tag, typ, count, value, data in entries:
fp.write(data)
if len(data) & 1:
fp.write(b"\0")
return offset
# -- overwrite here for multi-page --
fp.write(b"\0\0\0\0") # end of entries
# pass 3: write auxiliary data to file
for tag, typ, count, value, data in entries:
fp.write(data)
if len(data) & 1:
fp.write(b"\0")
return offset
ImageFileDirectory_v2._load_dispatch = _load_dispatch
ImageFileDirectory_v2._write_dispatch = _write_dispatch
for idx, name in TYPES.items():
name = name.replace(" ", "_")
setattr(ImageFileDirectory_v2, "load_" + name, _load_dispatch[idx][1])
setattr(ImageFileDirectory_v2, "write_" + name, _write_dispatch[idx])
del _load_dispatch, _write_dispatch, idx, name
# Legacy ImageFileDirectory support.
class ImageFileDirectory_v1(ImageFileDirectory_v2):
"""This class represents the **legacy** interface to a TIFF tag directory.
Exposes a dictionary interface of the tags in the directory::
ifd = ImageFileDirectory_v1()
ifd[key] = 'Some Data'
ifd.tagtype[key] = 2
