PIL.TiffImagePlugin 源代码
#
# The Python Imaging Library.
# $Id$
#
# TIFF file handling
#
# TIFF is a flexible, if somewhat aged, image file format originally
# defined by Aldus. Although TIFF supports a wide variety of pixel
# layouts and compression methods, the name doesn't really stand for
# "thousands of incompatible file formats," it just feels that way.
#
# To read TIFF data from a stream, the stream must be seekable. For
# progressive decoding, make sure to use TIFF files where the tag
# directory is placed first in the file.
#
# History:
# 1995-09-01 fl Created
# 1996-05-04 fl Handle JPEGTABLES tag
# 1996-05-18 fl Fixed COLORMAP support
# 1997-01-05 fl Fixed PREDICTOR support
# 1997-08-27 fl Added support for rational tags (from Perry Stoll)
# 1998-01-10 fl Fixed seek/tell (from Jan Blom)
# 1998-07-15 fl Use private names for internal variables
# 1999-06-13 fl Rewritten for PIL 1.0 (1.0)
# 2000-10-11 fl Additional fixes for Python 2.0 (1.1)
# 2001-04-17 fl Fixed rewind support (seek to frame 0) (1.2)
# 2001-05-12 fl Added write support for more tags (from Greg Couch) (1.3)
# 2001-12-18 fl Added workaround for broken Matrox library
# 2002-01-18 fl Don't mess up if photometric tag is missing (D. Alan Stewart)
# 2003-05-19 fl Check FILLORDER tag
# 2003-09-26 fl Added RGBa support
# 2004-02-24 fl Added DPI support; fixed rational write support
# 2005-02-07 fl Added workaround for broken Corel Draw 10 files
# 2006-01-09 fl Added support for float/double tags (from Russell Nelson)
#
# Copyright (c) 1997-2006 by Secret Labs AB. All rights reserved.
# Copyright (c) 1995-1997 by Fredrik Lundh
#
# See the README file for information on usage and redistribution.
#
import io
import itertools
import logging
import os
import struct
import warnings
from collections.abc import MutableMapping
from fractions import Fraction
from numbers import Number, Rational
from . import Image, ImageFile, ImageOps, ImagePalette, TiffTags
from ._binary import o8
from .TiffTags import TYPES
logger = logging.getLogger(__name__)
# Set these to true to force use of libtiff for reading or writing.
READ_LIBTIFF = False
WRITE_LIBTIFF = False
IFD_LEGACY_API = True
STRIP_SIZE = 65536
II = b"II" # little-endian (Intel style)
MM = b"MM" # big-endian (Motorola style)
#
# --------------------------------------------------------------------
# Read TIFF files
# a few tag names, just to make the code below a bit more readable
IMAGEWIDTH = 256
IMAGELENGTH = 257
BITSPERSAMPLE = 258
COMPRESSION = 259
PHOTOMETRIC_INTERPRETATION = 262
FILLORDER = 266
IMAGEDESCRIPTION = 270
STRIPOFFSETS = 273
SAMPLESPERPIXEL = 277
ROWSPERSTRIP = 278
STRIPBYTECOUNTS = 279
X_RESOLUTION = 282
Y_RESOLUTION = 283
PLANAR_CONFIGURATION = 284
RESOLUTION_UNIT = 296
TRANSFERFUNCTION = 301
SOFTWARE = 305
DATE_TIME = 306
ARTIST = 315
PREDICTOR = 317
COLORMAP = 320
TILEOFFSETS = 324
SUBIFD = 330
EXTRASAMPLES = 338
SAMPLEFORMAT = 339
JPEGTABLES = 347
YCBCRSUBSAMPLING = 530
REFERENCEBLACKWHITE = 532
COPYRIGHT = 33432
IPTC_NAA_CHUNK = 33723 # newsphoto properties
PHOTOSHOP_CHUNK = 34377 # photoshop properties
ICCPROFILE = 34675
EXIFIFD = 34665
XMP = 700
JPEGQUALITY = 65537 # pseudo-tag by libtiff
# https://github.com/imagej/ImageJA/blob/master/src/main/java/ij/io/TiffDecoder.java
IMAGEJ_META_DATA_BYTE_COUNTS = 50838
IMAGEJ_META_DATA = 50839
COMPRESSION_INFO = {
# Compression => pil compression name
1: "raw",
2: "tiff_ccitt",
3: "group3",
4: "group4",
5: "tiff_lzw",
6: "tiff_jpeg", # obsolete
7: "jpeg",
8: "tiff_adobe_deflate",
32771: "tiff_raw_16", # 16-bit padding
32773: "packbits",
32809: "tiff_thunderscan",
32946: "tiff_deflate",
34676: "tiff_sgilog",
34677: "tiff_sgilog24",
34925: "lzma",
50000: "zstd",
50001: "webp",
}
COMPRESSION_INFO_REV = {v: k for k, v in COMPRESSION_INFO.items()}
OPEN_INFO = {
# (ByteOrder, PhotoInterpretation, SampleFormat, FillOrder, BitsPerSample,
# ExtraSamples) => mode, rawmode
(II, 0, (1,), 1, (1,), ()): ("1", "1;I"),
(MM, 0, (1,), 1, (1,), ()): ("1", "1;I"),
(II, 0, (1,), 2, (1,), ()): ("1", "1;IR"),
(MM, 0, (1,), 2, (1,), ()): ("1", "1;IR"),
(II, 1, (1,), 1, (1,), ()): ("1", "1"),
(MM, 1, (1,), 1, (1,), ()): ("1", "1"),
(II, 1, (1,), 2, (1,), ()): ("1", "1;R"),
(MM, 1, (1,), 2, (1,), ()): ("1", "1;R"),
(II, 0, (1,), 1, (2,), ()): ("L", "L;2I"),
(MM, 0, (1,), 1, (2,), ()): ("L", "L;2I"),
(II, 0, (1,), 2, (2,), ()): ("L", "L;2IR"),
(MM, 0, (1,), 2, (2,), ()): ("L", "L;2IR"),
(II, 1, (1,), 1, (2,), ()): ("L", "L;2"),
(MM, 1, (1,), 1, (2,), ()): ("L", "L;2"),
(II, 1, (1,), 2, (2,), ()): ("L", "L;2R"),
(MM, 1, (1,), 2, (2,), ()): ("L", "L;2R"),
(II, 0, (1,), 1, (4,), ()): ("L", "L;4I"),
(MM, 0, (1,), 1, (4,), ()): ("L", "L;4I"),
(II, 0, (1,), 2, (4,), ()): ("L", "L;4IR"),
(MM, 0, (1,), 2, (4,), ()): ("L", "L;4IR"),
(II, 1, (1,), 1, (4,), ()): ("L", "L;4"),
(MM, 1, (1,), 1, (4,), ()): ("L", "L;4"),
(II, 1, (1,), 2, (4,), ()): ("L", "L;4R"),
(MM, 1, (1,), 2, (4,), ()): ("L", "L;4R"),
(II, 0, (1,), 1, (8,), ()): ("L", "L;I"),
(MM, 0, (1,), 1, (8,), ()): ("L", "L;I"),
(II, 0, (1,), 2, (8,), ()): ("L", "L;IR"),
(MM, 0, (1,), 2, (8,), ()): ("L", "L;IR"),
(II, 1, (1,), 1, (8,), ()): ("L", "L"),
(MM, 1, (1,), 1, (8,), ()): ("L", "L"),
(II, 1, (1,), 2, (8,), ()): ("L", "L;R"),
(MM, 1, (1,), 2, (8,), ()): ("L", "L;R"),
(II, 1, (1,), 1, (12,), ()): ("I;16", "I;12"),
(II, 1, (1,), 1, (16,), ()): ("I;16", "I;16"),
(MM, 1, (1,), 1, (16,), ()): ("I;16B", "I;16B"),
(II, 1, (2,), 1, (16,), ()): ("I", "I;16S"),
(MM, 1, (2,), 1, (16,), ()): ("I", "I;16BS"),
(II, 0, (3,), 1, (32,), ()): ("F", "F;32F"),
(MM, 0, (3,), 1, (32,), ()): ("F", "F;32BF"),
(II, 1, (1,), 1, (32,), ()): ("I", "I;32N"),
(II, 1, (2,), 1, (32,), ()): ("I", "I;32S"),
(MM, 1, (2,), 1, (32,), ()): ("I", "I;32BS"),
(II, 1, (3,), 1, (32,), ()): ("F", "F;32F"),
(MM, 1, (3,), 1, (32,), ()): ("F", "F;32BF"),
(II, 1, (1,), 1, (8, 8), (2,)): ("LA", "LA"),
(MM, 1, (1,), 1, (8, 8), (2,)): ("LA", "LA"),
(II, 2, (1,), 1, (8, 8, 8), ()): ("RGB", "RGB"),
(MM, 2, (1,), 1, (8, 8, 8), ()): ("RGB", "RGB"),
(II, 2, (1,), 2, (8, 8, 8), ()): ("RGB", "RGB;R"),
(MM, 2, (1,), 2, (8, 8, 8), ()): ("RGB", "RGB;R"),
(II, 2, (1,), 1, (8, 8, 8, 8), ()): ("RGBA", "RGBA"), # missing ExtraSamples
(MM, 2, (1,), 1, (8, 8, 8, 8), ()): ("RGBA", "RGBA"), # missing ExtraSamples
(II, 2, (1,), 1, (8, 8, 8, 8), (0,)): ("RGBX", "RGBX"),
(MM, 2, (1,), 1, (8, 8, 8, 8), (0,)): ("RGBX", "RGBX"),
(II, 2, (1,), 1, (8, 8, 8, 8, 8), (0, 0)): ("RGBX", "RGBXX"),
(MM, 2, (1,), 1, (8, 8, 8, 8, 8), (0, 0)): ("RGBX", "RGBXX"),
(II, 2, (1,), 1, (8, 8, 8, 8, 8, 8), (0, 0, 0)): ("RGBX", "RGBXXX"),
(MM, 2, (1,), 1, (8, 8, 8, 8, 8, 8), (0, 0, 0)): ("RGBX", "RGBXXX"),
(II, 2, (1,), 1, (8, 8, 8, 8), (1,)): ("RGBA", "RGBa"),
(MM, 2, (1,), 1, (8, 8, 8, 8), (1,)): ("RGBA", "RGBa"),
(II, 2, (1,), 1, (8, 8, 8, 8, 8), (1, 0)): ("RGBA", "RGBaX"),
(MM, 2, (1,), 1, (8, 8, 8, 8, 8), (1, 0)): ("RGBA", "RGBaX"),
(II, 2, (1,), 1, (8, 8, 8, 8, 8, 8), (1, 0, 0)): ("RGBA", "RGBaXX"),
(MM, 2, (1,), 1, (8, 8, 8, 8, 8, 8), (1, 0, 0)): ("RGBA", "RGBaXX"),
(II, 2, (1,), 1, (8, 8, 8, 8), (2,)): ("RGBA", "RGBA"),
(MM, 2, (1,), 1, (8, 8, 8, 8), (2,)): ("RGBA", "RGBA"),
(II, 2, (1,), 1, (8, 8, 8, 8, 8), (2, 0)): ("RGBA", "RGBAX"),
(MM, 2, (1,), 1, (8, 8, 8, 8, 8), (2, 0)): ("RGBA", "RGBAX"),
(II, 2, (1,), 1, (8, 8, 8, 8, 8, 8), (2, 0, 0)): ("RGBA", "RGBAXX"),
(MM, 2, (1,), 1, (8, 8, 8, 8, 8, 8), (2, 0, 0)): ("RGBA", "RGBAXX"),
(II, 2, (1,), 1, (8, 8, 8, 8), (999,)): ("RGBA", "RGBA"), # Corel Draw 10
(MM, 2, (1,), 1, (8, 8, 8, 8), (999,)): ("RGBA", "RGBA"), # Corel Draw 10
(II, 2, (1,), 1, (16, 16, 16), ()): ("RGB", "RGB;16L"),
(MM, 2, (1,), 1, (16, 16, 16), ()): ("RGB", "RGB;16B"),
(II, 2, (1,), 1, (16, 16, 16, 16), ()): ("RGBA", "RGBA;16L"),
(MM, 2, (1,), 1, (16, 16, 16, 16), ()): ("RGBA", "RGBA;16B"),
(II, 2, (1,), 1, (16, 16, 16, 16), (0,)): ("RGBX", "RGBX;16L"),
(MM, 2, (1,), 1, (16, 16, 16, 16), (0,)): ("RGBX", "RGBX;16B"),
(II, 2, (1,), 1, (16, 16, 16, 16), (1,)): ("RGBA", "RGBa;16L"),
(MM, 2, (1,), 1, (16, 16, 16, 16), (1,)): ("RGBA", "RGBa;16B"),
(II, 2, (1,), 1, (16, 16, 16, 16), (2,)): ("RGBA", "RGBA;16L"),
(MM, 2, (1,), 1, (16, 16, 16, 16), (2,)): ("RGBA", "RGBA;16B"),
(II, 3, (1,), 1, (1,), ()): ("P", "P;1"),
(MM, 3, (1,), 1, (1,), ()): ("P", "P;1"),
(II, 3, (1,), 2, (1,), ()): ("P", "P;1R"),
(MM, 3, (1,), 2, (1,), ()): ("P", "P;1R"),
(II, 3, (1,), 1, (2,), ()): ("P", "P;2"),
(MM, 3, (1,), 1, (2,), ()): ("P", "P;2"),
(II, 3, (1,), 2, (2,), ()): ("P", "P;2R"),
(MM, 3, (1,), 2, (2,), ()): ("P", "P;2R"),
(II, 3, (1,), 1, (4,), ()): ("P", "P;4"),
(MM, 3, (1,), 1, (4,), ()): ("P", "P;4"),
(II, 3, (1,), 2, (4,), ()): ("P", "P;4R"),
(MM, 3, (1,), 2, (4,), ()): ("P", "P;4R"),
(II, 3, (1,), 1, (8,), ()): ("P", "P"),
(MM, 3, (1,), 1, (8,), ()): ("P", "P"),
(II, 3, (1,), 1, (8, 8), (2,)): ("PA", "PA"),
(MM, 3, (1,), 1, (8, 8), (2,)): ("PA", "PA"),
(II, 3, (1,), 2, (8,), ()): ("P", "P;R"),
(MM, 3, (1,), 2, (8,), ()): ("P", "P;R"),
(II, 5, (1,), 1, (8, 8, 8, 8), ()): ("CMYK", "CMYK"),
(MM, 5, (1,), 1, (8, 8, 8, 8), ()): ("CMYK", "CMYK"),
(II, 5, (1,), 1, (8, 8, 8, 8, 8), (0,)): ("CMYK", "CMYKX"),
(MM, 5, (1,), 1, (8, 8, 8, 8, 8), (0,)): ("CMYK", "CMYKX"),
(II, 5, (1,), 1, (8, 8, 8, 8, 8, 8), (0, 0)): ("CMYK", "CMYKXX"),
(MM, 5, (1,), 1, (8, 8, 8, 8, 8, 8), (0, 0)): ("CMYK", "CMYKXX"),
(II, 5, (1,), 1, (16, 16, 16, 16), ()): ("CMYK", "CMYK;16L"),
# JPEG compressed images handled by LibTiff and auto-converted to RGBX
# Minimal Baseline TIFF requires YCbCr images to have 3 SamplesPerPixel
(II, 6, (1,), 1, (8, 8, 8), ()): ("RGB", "RGBX"),
(MM, 6, (1,), 1, (8, 8, 8), ()): ("RGB", "RGBX"),
(II, 8, (1,), 1, (8, 8, 8), ()): ("LAB", "LAB"),
(MM, 8, (1,), 1, (8, 8, 8), ()): ("LAB", "LAB"),
}
PREFIXES = [
b"MM\x00\x2A", # Valid TIFF header with big-endian byte order
b"II\x2A\x00", # Valid TIFF header with little-endian byte order
b"MM\x2A\x00", # Invalid TIFF header, assume big-endian
b"II\x00\x2A", # Invalid TIFF header, assume little-endian
]
def _accept(prefix):
return prefix[:4] in PREFIXES
def _limit_rational(val, max_val):
inv = abs(val) > 1
n_d = IFDRational(1 / val if inv else val).limit_rational(max_val)
return n_d[::-1] if inv else n_d
def _limit_signed_rational(val, max_val, min_val):
frac = Fraction(val)
n_d = frac.numerator, frac.denominator
if min(n_d) < min_val:
n_d = _limit_rational(val, abs(min_val))
if max(n_d) > max_val:
val = Fraction(*n_d)
n_d = _limit_rational(val, max_val)
return n_d
##
# Wrapper for TIFF IFDs.
_load_dispatch = {}
_write_dispatch = {}
[文档]class IFDRational(Rational):
"""Implements a rational class where 0/0 is a legal value to match
the in the wild use of exif rationals.
e.g., DigitalZoomRatio - 0.00/0.00 indicates that no digital zoom was used
"""
""" If the denominator is 0, store this as a float('nan'), otherwise store
as a fractions.Fraction(). Delegate as appropriate
"""
__slots__ = ("_numerator", "_denominator", "_val")
def __init__(self, value, denominator=1):
"""
:param value: either an integer numerator, a
float/rational/other number, or an IFDRational
:param denominator: Optional integer denominator
"""
if isinstance(value, IFDRational):
self._numerator = value.numerator
self._denominator = value.denominator
self._val = value._val
return
if isinstance(value, Fraction):
self._numerator = value.numerator
self._denominator = value.denominator
else:
self._numerator = value
self._denominator = denominator
if denominator == 0:
self._val = float("nan")
elif denominator == 1:
self._val = Fraction(value)
else:
self._val = Fraction(value, denominator)
@property
def numerator(a):
return a._numerator
@property
def denominator(a):
return a._denominator
[文档] def limit_rational(self, max_denominator):
"""
:param max_denominator: Integer, the maximum denominator value
:returns: Tuple of (numerator, denominator)
"""
if self.denominator == 0:
return (self.numerator, self.denominator)
f = self._val.limit_denominator(max_denominator)
return (f.numerator, f.denominator)
def __repr__(self):
return str(float(self._val))
def __hash__(self):
return self._val.__hash__()
def __eq__(self, other):
val = self._val
if isinstance(other, IFDRational):
other = other._val
if isinstance(other, float):
val = float(val)
return val == other
def __getstate__(self):
return [self._val, self._numerator, self._denominator]
def __setstate__(self, state):
IFDRational.__init__(self, 0)
_val, _numerator, _denominator = state
self._val = _val
self._numerator = _numerator
self._denominator = _denominator
def _delegate(op):
def delegate(self, *args):
return getattr(self._val, op)(*args)
return delegate
""" a = ['add','radd', 'sub', 'rsub', 'mul', 'rmul',
'truediv', 'rtruediv', 'floordiv', 'rfloordiv',
'mod','rmod', 'pow','rpow', 'pos', 'neg',
'abs', 'trunc', 'lt', 'gt', 'le', 'ge', 'bool',
'ceil', 'floor', 'round']
print("\n".join("__%s__ = _delegate('__%s__')" % (s,s) for s in a))
"""
__add__ = _delegate("__add__")
__radd__ = _delegate("__radd__")
__sub__ = _delegate("__sub__")
__rsub__ = _delegate("__rsub__")
__mul__ = _delegate("__mul__")
__rmul__ = _delegate("__rmul__")
__truediv__ = _delegate("__truediv__")
__rtruediv__ = _delegate("__rtruediv__")
__floordiv__ = _delegate("__floordiv__")
__rfloordiv__ = _delegate("__rfloordiv__")
__mod__ = _delegate("__mod__")
__rmod__ = _delegate("__rmod__")
__pow__ = _delegate("__pow__")
__rpow__ = _delegate("__rpow__")
__pos__ = _delegate("__pos__")
__neg__ = _delegate("__neg__")
__abs__ = _delegate("__abs__")
__trunc__ = _delegate("__trunc__")
__lt__ = _delegate("__lt__")
__gt__ = _delegate("__gt__")
__le__ = _delegate("__le__")
__ge__ = _delegate("__ge__")
__bool__ = _delegate("__bool__")
__ceil__ = _delegate("__ceil__")
__floor__ = _delegate("__floor__")
__round__ = _delegate("__round__")
[文档]class ImageFileDirectory_v2(MutableMapping):
"""This class represents a TIFF tag directory. To speed things up, we
don't decode tags unless they're asked for.
Exposes a dictionary interface of the tags in the directory::
ifd = ImageFileDirectory_v2()
ifd[key] = 'Some Data'
ifd.tagtype[key] = TiffTags.ASCII
print(ifd[key])
'Some Data'
Individual values are returned as the strings or numbers, sequences are
returned as tuples of the values.
The tiff metadata type of each item is stored in a dictionary of
tag types in
:attr:`~PIL.TiffImagePlugin.ImageFileDirectory_v2.tagtype`. The types
are read from a tiff file, guessed from the type added, or added
manually.
Data Structures:
* ``self.tagtype = {}``
* Key: numerical TIFF tag number
* Value: integer corresponding to the data type from
:py:data:`.TiffTags.TYPES`
.. versionadded:: 3.0.0
'Internal' data structures:
* ``self._tags_v2 = {}``
* Key: numerical TIFF tag number
* Value: decoded data, as tuple for multiple values
* ``self._tagdata = {}``
* Key: numerical TIFF tag number
* Value: undecoded byte string from file
* ``self._tags_v1 = {}``
* Key: numerical TIFF tag number
* Value: decoded data in the v1 format
Tags will be found in the private attributes ``self._tagdata``, and in
``self._tags_v2`` once decoded.
``self.legacy_api`` is a value for internal use, and shouldn't be changed
from outside code. In cooperation with
:py:class:`~PIL.TiffImagePlugin.ImageFileDirectory_v1`, if ``legacy_api``
is true, then decoded tags will be populated into both ``_tags_v1`` and
``_tags_v2``. ``_tags_v2`` will be used if this IFD is used in the TIFF
save routine. Tags should be read from ``_tags_v1`` if
``legacy_api == true``.
"""
def __init__(self, ifh=b"II\052\0\0\0\0\0", prefix=None, group=None):
"""Initialize an ImageFileDirectory.
To construct an ImageFileDirectory from a real file, pass the 8-byte
magic header to the constructor. To only set the endianness, pass it
as the 'prefix' keyword argument.
:param ifh: One of the accepted magic headers (cf. PREFIXES); also sets
endianness.
:param prefix: Override the endianness of the file.
"""
if ifh[:4] not in PREFIXES:
raise SyntaxError(f"not a TIFF file (header {repr(ifh)} not valid)")
self._prefix = prefix if prefix is not None else ifh[:2]
if self._prefix == MM:
self._endian = ">"
elif self._prefix == II:
self._endian = "<"
else:
raise SyntaxError("not a TIFF IFD")
self.group = group
self.tagtype = {}
""" Dictionary of tag types """
self.reset()
(self.next,) = self._unpack("L", ifh[4:])
self._legacy_api = False
prefix = property(lambda self: self._prefix)
offset = property(lambda self: self._offset)
legacy_api = property(lambda self: self._legacy_api)
@legacy_api.setter
def legacy_api(self, value):
raise Exception("Not allowing setting of legacy api")
[文档] def reset(self):
self._tags_v1 = {} # will remain empty if legacy_api is false
self._tags_v2 = {} # main tag storage
self._tagdata = {}
self.tagtype = {} # added 2008-06-05 by Florian Hoech
self._next = None
self._offset = None
def __str__(self):
return str(dict(self))
[文档] def named(self):
"""
:returns: dict of name|key: value
Returns the complete tag dictionary, with named tags where possible.
"""
return {
TiffTags.lookup(code, self.group).name: value
for code, value in self.items()
}
def __len__(self):
return len(set(self._tagdata) | set(self._tags_v2))
def __getitem__(self, tag):
if tag not in self._tags_v2: # unpack on the fly
data = self._tagdata[tag]
typ = self.tagtype[tag]
size, handler = self._load_dispatch[typ]
self[tag] = handler(self, data, self.legacy_api) # check type
val = self._tags_v2[tag]
if self.legacy_api and not isinstance(val, (tuple, bytes)):
val = (val,)
return val
def __contains__(self, tag):
return tag in self._tags_v2 or tag in self._tagdata
def __setitem__(self, tag, value):
self._setitem(tag, value, self.legacy_api)
def _setitem(self, tag, value, legacy_api):
basetypes = (Number, bytes, str)
info = TiffTags.lookup(tag, self.group)
values = [value] if isinstance(value, basetypes) else value
if tag not in self.tagtype:
if info.type:
self.tagtype[tag] = info.type
else:
self.tagtype[tag] = TiffTags.UNDEFINED
if all(isinstance(v, IFDRational) for v in values):
self.tagtype[tag] = (
TiffTags.RATIONAL
if all(v >= 0 for v in values)
else TiffTags.SIGNED_RATIONAL
)
elif all(isinstance(v, int) for v in values):
if all(0 <= v < 2 ** 16 for v in values):
self.tagtype[tag] = TiffTags.SHORT
elif all(-(2 ** 15) < v < 2 ** 15 for v in values):
self.tagtype[tag] = TiffTags.SIGNED_SHORT
else:
self.tagtype[tag] = (
TiffTags.LONG
if all(v >= 0 for v in values)
else TiffTags.SIGNED_LONG
)
elif all(isinstance(v, float) for v in values):
self.tagtype[tag] = TiffTags.DOUBLE
elif all(isinstance(v, str) for v in values):
self.tagtype[tag] = TiffTags.ASCII
elif all(isinstance(v, bytes) for v in values):
self.tagtype[tag] = TiffTags.BYTE
if self.tagtype[tag] == TiffTags.UNDEFINED:
values = [
v.encode("ascii", "replace") if isinstance(v, str) else v
for v in values
]
elif self.tagtype[tag] == TiffTags.RATIONAL:
values = [float(v) if isinstance(v, int) else v for v in values]
is_ifd = self.tagtype[tag] == TiffTags.LONG and isinstance(values, dict)
if not is_ifd:
values = tuple(info.cvt_enum(value) for value in values)
dest = self._tags_v1 if legacy_api else self._tags_v2
# Three branches:
# Spec'd length == 1, Actual length 1, store as element
# Spec'd length == 1, Actual > 1, Warn and truncate. Formerly barfed.
# No Spec, Actual length 1, Formerly (<4.2) returned a 1 element tuple.
# Don't mess with the legacy api, since it's frozen.
if not is_ifd and (
(info.length == 1)
or self.tagtype[tag] == TiffTags.BYTE
or (info.length is None and len(values) == 1 and not legacy_api)
):
# Don't mess with the legacy api, since it's frozen.
if legacy_api and self.tagtype[tag] in [
TiffTags.RATIONAL,
TiffTags.SIGNED_RATIONAL,
]: # rationals
values = (values,)
try:
(dest[tag],) = values
except ValueError:
# We've got a builtin tag with 1 expected entry
warnings.warn(
f"Metadata Warning, tag {tag} had too many entries: "
f"{len(values)}, expected 1"
)
dest[tag] = values[0]
else:
# Spec'd length > 1 or undefined
# Unspec'd, and length > 1
dest[tag] = values
def __delitem__(self, tag):
self._tags_v2.pop(tag, None)
self._tags_v1.pop(tag, None)
self._tagdata.pop(tag, None)
def __iter__(self):
return iter(set(self._tagdata) | set(self._tags_v2))
def _unpack(self, fmt, data):
return struct.unpack(self._endian + fmt, data)
def _pack(self, fmt, *values):
return struct.pack(self._endian + fmt, *values)
def _register_loader(idx, size):
def decorator(func):
from .TiffTags import TYPES
if func.__name__.startswith("load_"):
TYPES[idx] = func.__name__[5:].replace("_", " ")
_load_dispatch[idx] = size, func # noqa: F821
return func
return decorator
def _register_writer(idx):
def decorator(func):
_write_dispatch[idx] = func # noqa: F821
return func
return decorator
def _register_basic(idx_fmt_name):
from .TiffTags import TYPES
idx, fmt, name = idx_fmt_name
TYPES[idx] = name
size = struct.calcsize("=" + fmt)
_load_dispatch[idx] = ( # noqa: F821
size,
lambda self, data, legacy_api=True: (
self._unpack("{}{}".format(len(data) // size, fmt), data)
),
)
_write_dispatch[idx] = lambda self, *values: ( # noqa: F821
b"".join(self._pack(fmt, value) for value in values)
)
list(
map(
_register_basic,
[
(TiffTags.SHORT, "H", "short"),
(TiffTags.LONG, "L", "long"),
(TiffTags.SIGNED_BYTE, "b", "signed byte"),
(TiffTags.SIGNED_SHORT, "h", "signed short"),
(TiffTags.SIGNED_LONG, "l", "signed long"),
(TiffTags.FLOAT, "f", "float"),
(TiffTags.DOUBLE, "d", "double"),
(TiffTags.IFD, "L", "long"),
],
)
)
[文档] @_register_loader(1, 1) # Basic type, except for the legacy API.
def load_byte(self, data, legacy_api=True):
return data
[文档] @_register_writer(1) # Basic type, except for the legacy API.
def write_byte(self, data):
return data
[文档] @_register_loader(2, 1)
def load_string(self, data, legacy_api=True):
if data.endswith(b"\0"):
data = data[:-1]
return data.decode("latin-1", "replace")
[文档] @_register_writer(2)
def write_string(self, value):
# remerge of https://github.com/python-pillow/Pillow/pull/1416
return b"" + value.encode("ascii", "replace") + b"\0"
[文档] @_register_loader(5, 8)
def load_rational(self, data, legacy_api=True):
vals = self._unpack("{}L".format(len(data) // 4), data)
def combine(a, b):
return (a, b) if legacy_api else IFDRational(a, b)
return tuple(combine(num, denom) for num, denom in zip(vals[::2], vals[1::2]))
[文档] @_register_writer(5)
def write_rational(self, *values):
return b"".join(
self._pack("2L", *_limit_rational(frac, 2 ** 32 - 1)) for frac in values
)
[文档] @_register_loader(10, 8)
def load_signed_rational(self, data, legacy_api=True):
vals = self._unpack("{}l".format(len(data) // 4), data)
def combine(a, b):
return (a, b) if legacy_api else IFDRational(a, b)
return tuple(combine(num, denom) for num, denom in zip(vals[::2], vals[1::2]))
[文档] @_register_writer(10)
def write_signed_rational(self, *values):
return b"".join(
self._pack("2l", *_limit_signed_rational(frac, 2 ** 31 - 1, -(2 ** 31)))
for frac in values
)
def _ensure_read(self, fp, size):
ret = fp.read(size)
if len(ret) != size:
raise OSError(
"Corrupt EXIF data. "
f"Expecting to read {size} bytes but only got {len(ret)}. "
)
return ret
[文档] 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))
tagname = TiffTags.lookup(tag, self.group).name
typname = TYPES.get(typ, "unknown")
msg = f"tag: {tagname} ({tag}) - type: {typname} ({typ})"
try:
unit_size, handler = self._load_dispatch[typ]
except KeyError:
logger.debug(msg + f" - unsupported type {typ}")
continue # ignore unsupported type
size = count * unit_size
if size > 4:
here = fp.tell()
(offset,) = self._unpack("L", data)
msg += f" Tag Location: {here} - Data Location: {offset}"
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. "
f"Expecting to read {size} bytes but only got {len(data)}."
f" Skipping tag {tag}"
)
logger.debug(msg)
continue
if not data:
logger.debug(msg)
continue
self._tagdata[tag] = data
self.tagtype[tag] = typ
msg += " - value: " + (
"<table: %d bytes>" % size if size > 32 else repr(data)
)
logger.debug(msg)
(self.next,) = self._unpack("L", self._ensure_read(fp, 4))
except OSError as msg:
warnings.warn(str(msg))
return
[文档] def tobytes(self, offset=0):
# FIXME What about tagdata?
result = self._pack("H", len(self._tags_v2))
entries = []
offset = offset + len(result) + 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)
logger.debug(f"Tag {tag}, Type: {typ}, Value: {repr(value)}")
is_ifd = typ == TiffTags.LONG and isinstance(value, dict)
if is_ifd:
if self._endian == "<":
ifh = b"II\x2A\x00\x08\x00\x00\x00"
else:
ifh = b"MM\x00\x2A\x00\x00\x00\x08"
ifd = ImageFileDirectory_v2(ifh, group=tag)
values = self._tags_v2[tag]
for ifd_tag, ifd_value in values.items():
ifd[ifd_tag] = ifd_value
data = ifd.tobytes(offset)
else:
values = value if isinstance(value, tuple) else (value,)
data = self._write_dispatch[typ](self, *values)
tagname = TiffTags.lookup(tag, self.group).name
typname = "ifd" if is_ifd else TYPES.get(typ, "unknown")
msg = f"save: {tagname} ({tag}) - type: {typname} ({typ})"
msg += " - value: " + (
"<table: %d bytes>" % len(data) if len(data) >= 16 else str(values)
)
logger.debug(msg)
# count is sum of lengths for string and arbitrary data
if is_ifd:
count = 1
elif typ in [TiffTags.BYTE, TiffTags.ASCII, TiffTags.UNDEFINED]:
count = len(data)
else:
count = 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:
logger.debug(f"{tag} {typ} {count} {repr(value)} {repr(data)}")
result += self._pack("HHL4s", tag, typ, count, value)
# -- overwrite here for multi-page --
result += b"\0\0\0\0" # end of entries
# pass 3: write auxiliary data to file
for tag, typ, count, value, data in entries:
result += data
if len(data) & 1:
result += b"\0"
return result
[文档] 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))
offset = fp.tell()
result = self.tobytes(offset)
fp.write(result)
return offset + len(result)
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.
[文档]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] = TiffTags.ASCII
print(ifd[key])
('Some Data',)
Also contains a dictionary of tag types as read from the tiff image file,
:attr:`~PIL.TiffImagePlugin.ImageFileDirectory_v1.tagtype`.
Values are returned as a tuple.
.. deprecated:: 3.0.0
"""
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self._legacy_api = True
tags = property(lambda self: self._tags_v1)
tagdata = property(lambda self: self._tagdata)
# defined in ImageFileDirectory_v2
tagtype: dict
"""Dictionary of tag types"""
[文档] @classmethod
def from_v2(cls, original):
"""Returns an
:py:class:`~PIL.TiffImagePlugin.ImageFileDirectory_v1`
instance with the same data as is contained in the original
:py:class:`~PIL.TiffImagePlugin.ImageFileDirectory_v2`
instance.
:returns: :py:class:`~PIL.TiffImagePlugin.ImageFileDirectory_v1`
"""
ifd = cls(prefix=original.prefix)
ifd._tagdata = original._tagdata
ifd.tagtype = original.tagtype
ifd.next = original.next # an indicator for multipage tiffs
return ifd
[文档] def to_v2(self):
"""Returns an
:py:class:`~PIL.TiffImagePlugin.ImageFileDirectory_v2`
instance with the same data as is contained in the original
:py:class:`~PIL.TiffImagePlugin.ImageFileDirectory_v1`
instance.
:returns: :py:class:`~PIL.TiffImagePlugin.ImageFileDirectory_v2`
"""
ifd = ImageFileDirectory_v2(prefix=self.prefix)
ifd._tagdata = dict(self._tagdata)
ifd.tagtype = dict(self.tagtype)
ifd._tags_v2 = dict(self._tags_v2)
return ifd
def __contains__(self, tag):
return tag in self._tags_v1 or tag in self._tagdata
def __len__(self):
return len(set(self._tagdata) | set(self._tags_v1))
def __iter__(self):
return iter(set(self._tagdata) | set(self._tags_v1))
def __setitem__(self, tag, value):
for legacy_api in (False, True):
self._setitem(tag, value, legacy_api)
def __getitem__(self, tag):
if tag not in self._tags_v1: # unpack on the fly
data = self._tagdata[tag]
typ = self.tagtype[tag]
size, handler = self._load_dispatch[typ]
for legacy in (False, True):
self._setitem(tag, handler(self, data, legacy), legacy)
val = self._tags_v1[tag]
if not isinstance(val, (tuple, bytes)):
val = (val,)
return val
# undone -- switch this pointer when IFD_LEGACY_API == False
ImageFileDirectory = ImageFileDirectory_v1
##
# Image plugin for TIFF files.
[文档]class TiffImageFile(ImageFile.ImageFile):
format = "TIFF"
format_description = "Adobe TIFF"
_close_exclusive_fp_after_loading = False
def __init__(self, fp=None, filename=None):
self.tag_v2 = None
""" Image file directory (tag dictionary) """
self.tag = None
""" Legacy tag entries """
super().__init__(fp, filename)
def _open(self):
"""Open the first image in a TIFF file"""
# Header
ifh = self.fp.read(8)
self.tag_v2 = ImageFileDirectory_v2(ifh)
# legacy IFD entries will be filled in later
self.ifd = None
# setup frame pointers
self.__first = self.__next = self.tag_v2.next
self.__frame = -1
self.__fp = self.fp
self._frame_pos = []
self._n_frames = None
logger.debug("*** TiffImageFile._open ***")
logger.debug(f"- __first: {self.__first}")
logger.debug(f"- ifh: {repr(ifh)}") # Use repr to avoid str(bytes)
# and load the first frame
self._seek(0)
@property
def n_frames(self):
if self._n_frames is None:
current = self.tell()
self._seek(len(self._frame_pos))
while self._n_frames is None:
self._seek(self.tell() + 1)
self.seek(current)
return self._n_frames
[文档] def seek(self, frame):
"""Select a given frame as current image"""
if not self._seek_check(frame):
return
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 _seek(self, frame):
self.fp = self.__fp
# reset buffered io handle in case fp
# was passed to libtiff, invalidating the buffer
self.fp.tell()
while len(self._frame_pos) <= frame:
if not self.__next:
raise EOFError("no more images in TIFF file")
logger.debug(
f"Seeking to frame {frame}, on frame {self.__frame}, "
f"__next {self.__next}, location: {self.fp.tell()}"
)
self.fp.seek(self.__next)
self._frame_pos.append(self.__next)
logger.debug("Loading tags, location: %s" % self.fp.tell())
self.tag_v2.load(self.fp)
if self.tag_v2.next in self._frame_pos:
# This IFD has already been processed
# Declare this to be the end of the image
self.__next = 0
else:
self.__next = self.tag_v2.next
if self.__next == 0:
self._n_frames = frame + 1
if len(self._frame_pos) == 1:
self.is_animated = self.__next != 0
self.__frame += 1
self.fp.seek(self._frame_pos[frame])
self.tag_v2.load(self.fp)
# fill the legacy tag/ifd entries
self.tag = self.ifd = ImageFileDirectory_v1.from_v2(self.tag_v2)
self.__frame = frame
self._setup()
[文档] def getxmp(self):
"""
Returns a dictionary containing the XMP tags.
Requires defusedxml to be installed.
:returns: XMP tags in a dictionary.
"""
return self._getxmp(self.tag_v2[700]) if 700 in self.tag_v2 else {}
[文档] def load(self):
if self.tile and self.use_load_libtiff:
return self._load_libtiff()
return super().load()
[文档] def load_end(self):
if self._tile_orientation:
method = {
2: Image.FLIP_LEFT_RIGHT,
3: Image.ROTATE_180,
4: Image.FLIP_TOP_BOTTOM,
5: Image.TRANSPOSE,
6: Image.ROTATE_270,
7: Image.TRANSVERSE,
8: Image.ROTATE_90,
}.get(self._tile_orientation)
if method is not None:
self.im = self.im.transpose(method)
self._size = self.im.size
# allow closing if we're on the first frame, there's no next
# This is the ImageFile.load path only, libtiff specific below.
if not self.is_animated:
self._close_exclusive_fp_after_loading = True
# reset buffered io handle in case fp
# was passed to libtiff, invalidating the buffer
self.fp.tell()
# load IFD data from fp before it is closed
exif = self.getexif()
for key in TiffTags.TAGS_V2_GROUPS.keys():
if key not in exif:
continue
exif.get_ifd(key)
def _load_libtiff(self):
"""Overload method triggered when we detect a compressed tiff
Calls out to libtiff"""
Image.Image.load(self)
self.load_prepare()
if not len(self.tile) == 1:
raise OSError("Not exactly one tile")
# (self._compression, (extents tuple),
# 0, (rawmode, self._compression, fp))
extents = self.tile[0][1]
args = list(self.tile[0][3])
# To be nice on memory footprint, if there's a
# file descriptor, use that instead of reading
# into a string in python.
# libtiff closes the file descriptor, so pass in a dup.
try:
fp = hasattr(self.fp, "fileno") and os.dup(self.fp.fileno())
# flush the file descriptor, prevents error on pypy 2.4+
# should also eliminate the need for fp.tell
# in _seek
if hasattr(self.fp, "flush"):
self.fp.flush()
except OSError:
# io.BytesIO have a fileno, but returns an OSError if
# it doesn't use a file descriptor.
fp = False
if fp:
args[2] = fp
decoder = Image._getdecoder(
self.mode, "libtiff", tuple(args), self.decoderconfig
)
try:
decoder.setimage(self.im, extents)
except ValueError as e:
raise OSError("Couldn't set the image") from e
close_self_fp = self._exclusive_fp and not self.is_animated
if hasattr(self.fp, "getvalue"):
# We've got a stringio like thing passed in. Yay for all in memory.
# The decoder needs the entire file in one shot, so there's not
# a lot we can do here other than give it the entire file.
# unless we could do something like get the address of the
# underlying string for stringio.
#
# Rearranging for supporting byteio items, since they have a fileno
# that returns an OSError if there's no underlying fp. Easier to
# deal with here by reordering.
logger.debug("have getvalue. just sending in a string from getvalue")
n, err = decoder.decode(self.fp.getvalue())
elif fp:
# we've got a actual file on disk, pass in the fp.
logger.debug("have fileno, calling fileno version of the decoder.")
if not close_self_fp:
self.fp.seek(0)
# 4 bytes, otherwise the trace might error out
n, err = decoder.decode(b"fpfp")
else:
# we have something else.
logger.debug("don't have fileno or getvalue. just reading")
self.fp.seek(0)
# UNDONE -- so much for that buffer size thing.
n, err = decoder.decode(self.fp.read())
self.tile = []
self.readonly = 0
self.load_end()
# libtiff closed the fp in a, we need to close self.fp, if possible
if close_self_fp:
self.fp.close()
self.fp = None # might be shared
if err < 0:
raise OSError(err)
return Image.Image.load(self)
def _setup(self):
"""Setup this image object based on current tags"""
if 0xBC01 in self.tag_v2:
raise OSError("Windows Media Photo files not yet supported")
# extract relevant tags
self._compression = COMPRESSION_INFO[self.tag_v2.get(COMPRESSION, 1)]
self._planar_configuration = self.tag_v2.get(PLANAR_CONFIGURATION, 1)
# photometric is a required tag, but not everyone is reading
# the specification
photo = self.tag_v2.get(PHOTOMETRIC_INTERPRETATION, 0)
# old style jpeg compression images most certainly are YCbCr
if self._compression == "tiff_jpeg":
photo = 6
fillorder = self.tag_v2.get(FILLORDER, 1)
logger.debug("*** Summary ***")
logger.debug(f"- compression: {self._compression}")
logger.debug(f"- photometric_interpretation: {photo}")
logger.debug(f"- planar_configuration: {self._planar_configuration}")
logger.debug(f"- fill_order: {fillorder}")
logger.debug(f"- YCbCr subsampling: {self.tag.get(530)}")
# size
xsize = int(self.tag_v2.get(IMAGEWIDTH))
ysize = int(self.tag_v2.get(IMAGELENGTH))
self._size = xsize, ysize
logger.debug(f"- size: {self.size}")
sampleFormat = self.tag_v2.get(SAMPLEFORMAT, (1,))
if len(sampleFormat) > 1 and max(sampleFormat) == min(sampleFormat) == 1:
# SAMPLEFORMAT is properly per band, so an RGB image will
# be (1,1,1). But, we don't support per band pixel types,
# and anything more than one band is a uint8. So, just
# take the first element. Revisit this if adding support
# for more exotic images.
sampleFormat = (1,)
bps_tuple = self.tag_v2.get(BITSPERSAMPLE, (1,))
extra_tuple = self.tag_v2.get(EXTRASAMPLES, ())
if photo in (2, 6, 8): # RGB, YCbCr, LAB
bps_count = 3
elif photo == 5: # CMYK
bps_count = 4
else:
bps_count = 1
bps_count += len(extra_tuple)
# Some files have only one value in bps_tuple,
# while should have more. Fix it
if bps_count > len(bps_tuple) and len(bps_tuple) == 1:
bps_tuple = bps_tuple * bps_count
samplesPerPixel = self.tag_v2.get(
SAMPLESPERPIXEL,
3 if self._compression == "tiff_jpeg" and photo in (2, 6) else 1,
)
if len(bps_tuple) != samplesPerPixel:
raise SyntaxError("unknown data organization")
# mode: check photometric interpretation and bits per pixel
key = (
self.tag_v2.prefix,
photo,
sampleFormat,
fillorder,
bps_tuple,
extra_tuple,
)
logger.debug(f"format key: {key}")
try:
self.mode, rawmode = OPEN_INFO[key]
except KeyError as e:
logger.debug("- unsupported format")
raise SyntaxError("unknown pixel mode") from e
logger.debug(f"- raw mode: {rawmode}")
logger.debug(f"- pil mode: {self.mode}")
self.info["compression"] = self._compression
xres = self.tag_v2.get(X_RESOLUTION, 1)
yres = self.tag_v2.get(Y_RESOLUTION, 1)
if xres and yres:
resunit = self.tag_v2.get(RESOLUTION_UNIT)
if resunit == 2: # dots per inch
self.info["dpi"] = (xres, yres)
elif resunit == 3: # dots per centimeter. convert to dpi
self.info["dpi"] = (xres * 2.54, yres * 2.54)
elif resunit is None: # used to default to 1, but now 2)
self.info["dpi"] = (xres, yres)
# For backward compatibility,
# we also preserve the old behavior
self.info["resolution"] = xres, yres
else: # No absolute unit of measurement
self.info["resolution"] = xres, yres
# build tile descriptors
x = y = layer = 0
self.tile = []
self.use_load_libtiff = READ_LIBTIFF or self._compression != "raw"
if self.use_load_libtiff:
# Decoder expects entire file as one tile.
# There's a buffer size limit in load (64k)
# so large g4 images will fail if we use that
# function.
#
# Setup the one tile for the whole image, then
# use the _load_libtiff function.
# libtiff handles the fillmode for us, so 1;IR should
# actually be 1;I. Including the R double reverses the
# bits, so stripes of the image are reversed. See
# https://github.com/python-pillow/Pillow/issues/279
if fillorder == 2:
# Replace fillorder with fillorder=1
key = key[:3] + (1,) + key[4:]
logger.debug(f"format key: {key}")
# this should always work, since all the
# fillorder==2 modes have a corresponding
# fillorder=1 mode
self.mode, rawmode = OPEN_INFO[key]
# libtiff always returns the bytes in native order.
# we're expecting image byte order. So, if the rawmode
# contains I;16, we need to convert from native to image
# byte order.
if rawmode == "I;16":
rawmode = "I;16N"
if ";16B" in rawmode:
rawmode = rawmode.replace(";16B", ";16N")
if ";16L" in rawmode:
rawmode = rawmode.replace(";16L", ";16N")
# YCbCr images with new jpeg compression with pixels in one plane
# unpacked straight into RGB values
if (
photo == 6
and self._compression == "jpeg"
and self._planar_configuration == 1
):
rawmode = "RGB"
# Offset in the tile tuple is 0, we go from 0,0 to
# w,h, and we only do this once -- eds
a = (rawmode, self._compression, False, self.tag_v2.offset)
self.tile.append(("libtiff", (0, 0, xsize, ysize), 0, a))
elif STRIPOFFSETS in self.tag_v2 or TILEOFFSETS in self.tag_v2:
# striped image
if STRIPOFFSETS in self.tag_v2:
offsets = self.tag_v2[STRIPOFFSETS]
h = self.tag_v2.get(ROWSPERSTRIP, ysize)
w = self.size[0]
else:
# tiled image
offsets = self.tag_v2[TILEOFFSETS]
w = self.tag_v2.get(322)
h = self.tag_v2.get(323)
for offset in offsets:
if x + w > xsize:
stride = w * sum(bps_tuple) / 8 # bytes per line
else:
stride = 0
tile_rawmode = rawmode
if self._planar_configuration == 2:
# each band on it's own layer
tile_rawmode = rawmode[layer]
# adjust stride width accordingly
stride /= bps_count
a = (tile_rawmode, int(stride), 1)
self.tile.append(
(
self._compression,
(x, y, min(x + w, xsize), min(y + h, ysize)),
offset,
a,
)
)
x = x + w
if x >= self.size[0]:
x, y = 0, y + h
if y >= self.size[1]:
x = y = 0
layer += 1
else:
logger.debug("- unsupported data organization")
raise SyntaxError("unknown data organization")
# Fix up info.
if ICCPROFILE in self.tag_v2:
self.info["icc_profile"] = self.tag_v2[ICCPROFILE]
# fixup palette descriptor
if self.mode in ["P", "PA"]:
palette = [o8(b // 256) for b in self.tag_v2[COLORMAP]]
self.palette = ImagePalette.raw("RGB;L", b"".join(palette))
self._tile_orientation = self.tag_v2.get(0x0112)
def _close__fp(self):
try:
if self.__fp != self.fp:
self.__fp.close()
except AttributeError:
pass
finally:
self.__fp = None
#
# --------------------------------------------------------------------
# Write TIFF files
# little endian is default except for image modes with
# explicit big endian byte-order
SAVE_INFO = {
# mode => rawmode, byteorder, photometrics,
# sampleformat, bitspersample, extra
"1": ("1", II, 1, 1, (1,), None),
"L": ("L", II, 1, 1, (8,), None),
"LA": ("LA", II, 1, 1, (8, 8), 2),
"P": ("P", II, 3, 1, (8,), None),
"PA": ("PA", II, 3, 1, (8, 8), 2),
"I": ("I;32S", II, 1, 2, (32,), None),
"I;16": ("I;16", II, 1, 1, (16,), None),
"I;16S": ("I;16S", II, 1, 2, (16,), None),
"F": ("F;32F", II, 1, 3, (32,), None),
"RGB": ("RGB", II, 2, 1, (8, 8, 8), None),
"RGBX": ("RGBX", II, 2, 1, (8, 8, 8, 8), 0),
"RGBA": ("RGBA", II, 2, 1, (8, 8, 8, 8), 2),
"CMYK": ("CMYK", II, 5, 1, (8, 8, 8, 8), None),
"YCbCr": ("YCbCr", II, 6, 1, (8, 8, 8), None),
"LAB": ("LAB", II, 8, 1, (8, 8, 8), None),
"I;32BS": ("I;32BS", MM, 1, 2, (32,), None),
"I;16B": ("I;16B", MM, 1, 1, (16,), None),
"I;16BS": ("I;16BS", MM, 1, 2, (16,), None),
"F;32BF": ("F;32BF", MM, 1, 3, (32,), None),
}
def _save(im, fp, filename):
try:
rawmode, prefix, photo, format, bits, extra = SAVE_INFO[im.mode]
except KeyError as e:
raise OSError(f"cannot write mode {im.mode} as TIFF") from e
ifd = ImageFileDirectory_v2(prefix=prefix)
encoderinfo = im.encoderinfo
encoderconfig = im.encoderconfig
compression = encoderinfo.get("compression", im.info.get("compression"))
if compression is None:
compression = "raw"
elif compression == "tiff_jpeg":
# OJPEG is obsolete, so use new-style JPEG compression instead
compression = "jpeg"
elif compression == "tiff_deflate":
compression = "tiff_adobe_deflate"
libtiff = WRITE_LIBTIFF or compression != "raw"
# required for color libtiff images
ifd[PLANAR_CONFIGURATION] = getattr(im, "_planar_configuration", 1)
ifd[IMAGEWIDTH] = im.size[0]
ifd[IMAGELENGTH] = im.size[1]
# write any arbitrary tags passed in as an ImageFileDirectory
if "tiffinfo" in encoderinfo:
info = encoderinfo["tiffinfo"]
elif "exif" in encoderinfo:
info = encoderinfo["exif"]
if isinstance(info, bytes):
exif = Image.Exif()
exif.load(info)
info = exif
else:
info = {}
logger.debug("Tiffinfo Keys: %s" % list(info))
if isinstance(info, ImageFileDirectory_v1):
info = info.to_v2()
for key in info:
if isinstance(info, Image.Exif) and key in TiffTags.TAGS_V2_GROUPS.keys():
ifd[key] = info.get_ifd(key)
else:
ifd[key] = info.get(key)
try:
ifd.tagtype[key] = info.tagtype[key]
except Exception:
pass # might not be an IFD. Might not have populated type
# additions written by Greg Couch, gregc@cgl.ucsf.edu
# inspired by image-sig posting from Kevin Cazabon, kcazabon@home.com
if hasattr(im, "tag_v2"):
# preserve tags from original TIFF image file
for key in (
RESOLUTION_UNIT,
X_RESOLUTION,
Y_RESOLUTION,
IPTC_NAA_CHUNK,
PHOTOSHOP_CHUNK,
XMP,
):
if key in im.tag_v2:
ifd[key] = im.tag_v2[key]
ifd.tagtype[key] = im.tag_v2.tagtype[key]
# preserve ICC profile (should also work when saving other formats
# which support profiles as TIFF) -- 2008-06-06 Florian Hoech
icc = encoderinfo.get("icc_profile", im.info.get("icc_profile"))
if icc:
ifd[ICCPROFILE] = icc
for key, name in [
(IMAGEDESCRIPTION, "description"),
(X_RESOLUTION, "resolution"),
(Y_RESOLUTION, "resolution"),
(X_RESOLUTION, "x_resolution"),
(Y_RESOLUTION, "y_resolution"),
(RESOLUTION_UNIT, "resolution_unit"),
(SOFTWARE, "software"),
(DATE_TIME, "date_time"),
(ARTIST, "artist"),
(COPYRIGHT, "copyright"),
]:
if name in encoderinfo:
ifd[key] = encoderinfo[name]
dpi = encoderinfo.get("dpi")
if dpi:
ifd[RESOLUTION_UNIT] = 2
ifd[X_RESOLUTION] = dpi[0]
ifd[Y_RESOLUTION] = dpi[1]
if bits != (1,):
ifd[BITSPERSAMPLE] = bits
if len(bits) != 1:
ifd[SAMPLESPERPIXEL] = len(bits)
if extra is not None:
ifd[EXTRASAMPLES] = extra
if format != 1:
ifd[SAMPLEFORMAT] = format
if PHOTOMETRIC_INTERPRETATION not in ifd:
ifd[PHOTOMETRIC_INTERPRETATION] = photo
elif im.mode in ("1", "L") and ifd[PHOTOMETRIC_INTERPRETATION] == 0:
if im.mode == "1":
inverted_im = im.copy()
px = inverted_im.load()
for y in range(inverted_im.height):
for x in range(inverted_im.width):
px[x, y] = 0 if px[x, y] == 255 else 255
im = inverted_im
else:
im = ImageOps.invert(im)
if im.mode in ["P", "PA"]:
lut = im.im.getpalette("RGB", "RGB;L")
ifd[COLORMAP] = tuple(v * 256 for v in lut)
# data orientation
stride = len(bits) * ((im.size[0] * bits[0] + 7) // 8)
# aim for given strip size (64 KB by default) when using libtiff writer
if libtiff:
rows_per_strip = 1 if stride == 0 else min(STRIP_SIZE // stride, im.size[1])
# JPEG encoder expects multiple of 8 rows
if compression == "jpeg":
rows_per_strip = min(((rows_per_strip + 7) // 8) * 8, im.size[1])
else:
rows_per_strip = im.size[1]
if rows_per_strip == 0:
rows_per_strip = 1
strip_byte_counts = 1 if stride == 0 else stride * rows_per_strip
strips_per_image = (im.size[1] + rows_per_strip - 1) // rows_per_strip
ifd[ROWSPERSTRIP] = rows_per_strip
if strip_byte_counts >= 2 ** 16:
ifd.tagtype[STRIPBYTECOUNTS] = TiffTags.LONG
ifd[STRIPBYTECOUNTS] = (strip_byte_counts,) * (strips_per_image - 1) + (
stride * im.size[1] - strip_byte_counts * (strips_per_image - 1),
)
ifd[STRIPOFFSETS] = tuple(
range(0, strip_byte_counts * strips_per_image, strip_byte_counts)
) # this is adjusted by IFD writer
# no compression by default:
ifd[COMPRESSION] = COMPRESSION_INFO_REV.get(compression, 1)
if im.mode == "YCbCr":
for tag, value in {
YCBCRSUBSAMPLING: (1, 1),
REFERENCEBLACKWHITE: (0, 255, 128, 255, 128, 255),
}.items():
ifd.setdefault(tag, value)
if libtiff:
if "quality" in encoderinfo:
quality = encoderinfo["quality"]
if not isinstance(quality, int) or quality < 0 or quality > 100:
raise ValueError("Invalid quality setting")
if compression != "jpeg":
raise ValueError(
"quality setting only supported for 'jpeg' compression"
)
ifd[JPEGQUALITY] = quality
logger.debug("Saving using libtiff encoder")
logger.debug("Items: %s" % sorted(ifd.items()))
_fp = 0
if hasattr(fp, "fileno"):
try:
fp.seek(0)
_fp = os.dup(fp.fileno())
except io.UnsupportedOperation:
pass
# optional types for non core tags
types = {}
# SAMPLEFORMAT is determined by the image format and should not be copied
# from legacy_ifd.
# STRIPOFFSETS and STRIPBYTECOUNTS are added by the library
# based on the data in the strip.
# The other tags expect arrays with a certain length (fixed or depending on
# BITSPERSAMPLE, etc), passing arrays with a different length will result in
# segfaults. Block these tags until we add extra validation.
# SUBIFD may also cause a segfault.
blocklist = [
REFERENCEBLACKWHITE,
SAMPLEFORMAT,
STRIPBYTECOUNTS,
STRIPOFFSETS,
TRANSFERFUNCTION,
SUBIFD,
]
atts = {}
# bits per sample is a single short in the tiff directory, not a list.
atts[BITSPERSAMPLE] = 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()
for tag, value in itertools.chain(
ifd.items(), getattr(im, "tag_v2", {}).items(), legacy_ifd.items()
):
# Libtiff can only process certain core items without adding
# them to the custom dictionary.
# Custom items are supported for int, float, unicode, string and byte
# values. Other types and tuples require a tagtype.
if tag not in TiffTags.LIBTIFF_CORE:
if not Image.core.libtiff_support_custom_tags:
continue
if tag in ifd.tagtype:
types[tag] = ifd.tagtype[tag]
elif not (isinstance(value, (int, float, str, bytes))):
continue
else:
type = TiffTags.lookup(tag).type
if type:
types[tag] = type
if tag not in atts and tag not in blocklist:
if isinstance(value, str):
atts[tag] = value.encode("ascii", "replace") + b"\0"
elif isinstance(value, IFDRational):
atts[tag] = float(value)
else:
atts[tag] = value
logger.debug("Converted items: %s" % sorted(atts.items()))
# libtiff always expects the bytes in native order.
# we're storing image byte order. So, if the rawmode
# contains I;16, we need to convert from native to image
# byte order.
if im.mode in ("I;16B", "I;16"):
rawmode = "I;16N"
# Pass tags as sorted list so that the tags are set in a fixed order.
# This is required by libtiff for some tags. For example, the JPEGQUALITY
# pseudo tag requires that the COMPRESS tag was already set.
tags = list(atts.items())
tags.sort()
a = (rawmode, compression, _fp, filename, tags, types)
e = Image._getencoder(im.mode, "libtiff", a, encoderconfig)
e.setimage(im.im, (0, 0) + im.size)
while True:
# undone, change to self.decodermaxblock:
l, s, d = e.encode(16 * 1024)
if not _fp:
fp.write(d)
if s:
break
if s < 0:
raise OSError(f"encoder error {s} when writing image file")
else:
offset = ifd.save(fp)
ImageFile._save(
im, fp, [("raw", (0, 0) + im.size, offset, (rawmode, stride, 1))]
)
# -- helper for multi-page save --
if "_debug_multipage" in encoderinfo:
# just to access o32 and o16 (using correct byte order)
im._debug_multipage = ifd
[文档]class AppendingTiffWriter:
fieldSizes = [
0, # None
1, # byte
1, # ascii
2, # short
4, # long
8, # rational
1, # sbyte
1, # undefined
2, # sshort
4, # slong
8, # srational
4, # float
8, # double
]
# StripOffsets = 273
# FreeOffsets = 288
# TileOffsets = 324
# JPEGQTables = 519
# JPEGDCTables = 520
# JPEGACTables = 521
Tags = {273, 288, 324, 519, 520, 521}
def __init__(self, fn, new=False):
if hasattr(fn, "read"):
self.f = fn
self.close_fp = False
else:
self.name = fn
self.close_fp = True
try:
self.f = open(fn, "w+b" if new else "r+b")
except OSError:
self.f = open(fn, "w+b")
self.beginning = self.f.tell()
self.setup()
[文档] def setup(self):
# Reset everything.
self.f.seek(self.beginning, os.SEEK_SET)
self.whereToWriteNewIFDOffset = None
self.offsetOfNewPage = 0
self.IIMM = IIMM = self.f.read(4)
if not IIMM:
# empty file - first page
self.isFirst = True
return
self.isFirst = False
if IIMM == b"II\x2a\x00":
self.setEndian("<")
elif IIMM == b"MM\x00\x2a":
self.setEndian(">")
else:
raise RuntimeError("Invalid TIFF file header")
self.skipIFDs()
self.goToEnd()
[文档] def finalize(self):
if self.isFirst:
return
# fix offsets
self.f.seek(self.offsetOfNewPage)
IIMM = self.f.read(4)
if not IIMM:
# raise RuntimeError("nothing written into new page")
# Make it easy to finish a frame without committing to a new one.
return
if IIMM != self.IIMM:
raise RuntimeError("IIMM of new page doesn't match IIMM of first page")
IFDoffset = self.readLong()
IFDoffset += self.offsetOfNewPage
self.f.seek(self.whereToWriteNewIFDOffset)
self.writeLong(IFDoffset)
self.f.seek(IFDoffset)
self.fixIFD()
def __enter__(self):
return self
def __exit__(self, exc_type, exc_value, traceback):
if self.close_fp:
self.close()
return False
[文档] def seek(self, offset, whence=io.SEEK_SET):
if whence == os.SEEK_SET:
offset += self.offsetOfNewPage
self.f.seek(offset, whence)
return self.tell()
[文档] def goToEnd(self):
self.f.seek(0, os.SEEK_END)
pos = self.f.tell()
# pad to 16 byte boundary
padBytes = 16 - pos % 16
if 0 < padBytes < 16:
self.f.write(bytes(padBytes))
self.offsetOfNewPage = self.f.tell()
[文档] def setEndian(self, endian):
self.endian = endian
self.longFmt = self.endian + "L"
self.shortFmt = self.endian + "H"
self.tagFormat = self.endian + "HHL"
[文档] def skipIFDs(self):
while True:
IFDoffset = self.readLong()
if IFDoffset == 0:
self.whereToWriteNewIFDOffset = self.f.tell() - 4
break
self.f.seek(IFDoffset)
numTags = self.readShort()
self.f.seek(numTags * 12, os.SEEK_CUR)
[文档] def rewriteLastShortToLong(self, value):
self.f.seek(-2, os.SEEK_CUR)
bytesWritten = self.f.write(struct.pack(self.longFmt, value))
if bytesWritten is not None and bytesWritten != 4:
raise RuntimeError(f"wrote only {bytesWritten} bytes but wanted 4")
[文档] def rewriteLastShort(self, value):
self.f.seek(-2, os.SEEK_CUR)
bytesWritten = self.f.write(struct.pack(self.shortFmt, value))
if bytesWritten is not None and bytesWritten != 2:
raise RuntimeError(f"wrote only {bytesWritten} bytes but wanted 2")
[文档] def rewriteLastLong(self, value):
self.f.seek(-4, os.SEEK_CUR)
bytesWritten = self.f.write(struct.pack(self.longFmt, value))
if bytesWritten is not None and bytesWritten != 4:
raise RuntimeError(f"wrote only {bytesWritten} bytes but wanted 4")
[文档] def writeShort(self, value):
bytesWritten = self.f.write(struct.pack(self.shortFmt, value))
if bytesWritten is not None and bytesWritten != 2:
raise RuntimeError(f"wrote only {bytesWritten} bytes but wanted 2")
[文档] def writeLong(self, value):
bytesWritten = self.f.write(struct.pack(self.longFmt, value))
if bytesWritten is not None and bytesWritten != 4:
raise RuntimeError(f"wrote only {bytesWritten} bytes but wanted 4")
[文档] def fixIFD(self):
numTags = self.readShort()
for i in range(numTags):
tag, fieldType, count = struct.unpack(self.tagFormat, self.f.read(8))
fieldSize = self.fieldSizes[fieldType]
totalSize = fieldSize * count
isLocal = totalSize <= 4
if not isLocal:
offset = self.readLong()
offset += self.offsetOfNewPage
self.rewriteLastLong(offset)
if tag in self.Tags:
curPos = self.f.tell()
if isLocal:
self.fixOffsets(
count, isShort=(fieldSize == 2), isLong=(fieldSize == 4)
)
self.f.seek(curPos + 4)
else:
self.f.seek(offset)
self.fixOffsets(
count, isShort=(fieldSize == 2), isLong=(fieldSize == 4)
)
self.f.seek(curPos)
offset = curPos = None
elif isLocal:
# skip the locally stored value that is not an offset
self.f.seek(4, os.SEEK_CUR)
[文档] def fixOffsets(self, count, isShort=False, isLong=False):
if not isShort and not isLong:
raise RuntimeError("offset is neither short nor long")
for i in range(count):
offset = self.readShort() if isShort else self.readLong()
offset += self.offsetOfNewPage
if isShort and offset >= 65536:
# offset is now too large - we must convert shorts to longs
if count != 1:
raise RuntimeError("not implemented") # XXX TODO
# simple case - the offset is just one and therefore it is
# local (not referenced with another offset)
self.rewriteLastShortToLong(offset)
self.f.seek(-10, os.SEEK_CUR)
self.writeShort(TiffTags.LONG) # rewrite the type to LONG
self.f.seek(8, os.SEEK_CUR)
elif isShort:
self.rewriteLastShort(offset)
else:
self.rewriteLastLong(offset)
def _save_all(im, fp, filename):
encoderinfo = im.encoderinfo.copy()
encoderconfig = im.encoderconfig
append_images = list(encoderinfo.get("append_images", []))
if not hasattr(im, "n_frames") and not append_images:
return _save(im, fp, filename)
cur_idx = im.tell()
try:
with AppendingTiffWriter(fp) as tf:
for ims in [im] + append_images:
ims.encoderinfo = encoderinfo
ims.encoderconfig = encoderconfig
if not hasattr(ims, "n_frames"):
nfr = 1
else:
nfr = ims.n_frames
for idx in range(nfr):
ims.seek(idx)
ims.load()
_save(ims, tf, filename)
tf.newFrame()
finally:
im.seek(cur_idx)
#
# --------------------------------------------------------------------
# Register
Image.register_open(TiffImageFile.format, TiffImageFile, _accept)
Image.register_save(TiffImageFile.format, _save)
Image.register_save_all(TiffImageFile.format, _save_all)
Image.register_extensions(TiffImageFile.format, [".tif", ".tiff"])
Image.register_mime(TiffImageFile.format, "image/tiff")
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