PIL.IcnsImagePlugin 源代码
#
# The Python Imaging Library.
# $Id$
#
# macOS icns file decoder, based on icns.py by Bob Ippolito.
#
# history:
# 2004-10-09 fl Turned into a PIL plugin; removed 2.3 dependencies.
# 2020-04-04 Allow saving on all operating systems.
#
# Copyright (c) 2004 by Bob Ippolito.
# Copyright (c) 2004 by Secret Labs.
# Copyright (c) 2004 by Fredrik Lundh.
# Copyright (c) 2014 by Alastair Houghton.
# Copyright (c) 2020 by Pan Jing.
#
# See the README file for information on usage and redistribution.
#
import io
import os
import struct
import sys
from PIL import Image, ImageFile, PngImagePlugin, features
enable_jpeg2k = features.check_codec("jpg_2000")
if enable_jpeg2k:
from PIL import Jpeg2KImagePlugin
MAGIC = b"icns"
HEADERSIZE = 8
[文档]def read_32t(fobj, start_length, size):
# The 128x128 icon seems to have an extra header for some reason.
(start, length) = start_length
fobj.seek(start)
sig = fobj.read(4)
if sig != b"\x00\x00\x00\x00":
raise SyntaxError("Unknown signature, expecting 0x00000000")
return read_32(fobj, (start + 4, length - 4), size)
[文档]def read_32(fobj, start_length, size):
"""
Read a 32bit RGB icon resource. Seems to be either uncompressed or
an RLE packbits-like scheme.
"""
(start, length) = start_length
fobj.seek(start)
pixel_size = (size[0] * size[2], size[1] * size[2])
sizesq = pixel_size[0] * pixel_size[1]
if length == sizesq * 3:
# uncompressed ("RGBRGBGB")
indata = fobj.read(length)
im = Image.frombuffer("RGB", pixel_size, indata, "raw", "RGB", 0, 1)
else:
# decode image
im = Image.new("RGB", pixel_size, None)
for band_ix in range(3):
data = []
bytesleft = sizesq
while bytesleft > 0:
byte = fobj.read(1)
if not byte:
break
byte = byte[0]
if byte & 0x80:
blocksize = byte - 125
byte = fobj.read(1)
for i in range(blocksize):
data.append(byte)
else:
blocksize = byte + 1
data.append(fobj.read(blocksize))
bytesleft -= blocksize
if bytesleft <= 0:
break
if bytesleft != 0:
raise SyntaxError(f"Error reading channel [{repr(bytesleft)} left]")
band = Image.frombuffer("L", pixel_size, b"".join(data), "raw", "L", 0, 1)
im.im.putband(band.im, band_ix)
return {"RGB": im}
[文档]def read_mk(fobj, start_length, size):
# Alpha masks seem to be uncompressed
start = start_length[0]
fobj.seek(start)
pixel_size = (size[0] * size[2], size[1] * size[2])
sizesq = pixel_size[0] * pixel_size[1]
band = Image.frombuffer("L", pixel_size, fobj.read(sizesq), "raw", "L", 0, 1)
return {"A": band}
[文档]def read_png_or_jpeg2000(fobj, start_length, size):
(start, length) = start_length
fobj.seek(start)
sig = fobj.read(12)
if sig[:8] == b"\x89PNG\x0d\x0a\x1a\x0a":
fobj.seek(start)
im = PngImagePlugin.PngImageFile(fobj)
Image._decompression_bomb_check(im.size)
return {"RGBA": im}
elif (
sig[:4] == b"\xff\x4f\xff\x51"
or sig[:4] == b"\x0d\x0a\x87\x0a"
or sig == b"\x00\x00\x00\x0cjP \x0d\x0a\x87\x0a"
):
if not enable_jpeg2k:
raise ValueError(
"Unsupported icon subimage format (rebuild PIL "
"with JPEG 2000 support to fix this)"
)
# j2k, jpc or j2c
fobj.seek(start)
jp2kstream = fobj.read(length)
f = io.BytesIO(jp2kstream)
im = Jpeg2KImagePlugin.Jpeg2KImageFile(f)
Image._decompression_bomb_check(im.size)
if im.mode != "RGBA":
im = im.convert("RGBA")
return {"RGBA": im}
else:
raise ValueError("Unsupported icon subimage format")
[文档]class IcnsFile:
SIZES = {
(512, 512, 2): [(b"ic10", read_png_or_jpeg2000)],
(512, 512, 1): [(b"ic09", read_png_or_jpeg2000)],
(256, 256, 2): [(b"ic14", read_png_or_jpeg2000)],
(256, 256, 1): [(b"ic08", read_png_or_jpeg2000)],
(128, 128, 2): [(b"ic13", read_png_or_jpeg2000)],
(128, 128, 1): [
(b"ic07", read_png_or_jpeg2000),
(b"it32", read_32t),
(b"t8mk", read_mk),
],
(64, 64, 1): [(b"icp6", read_png_or_jpeg2000)],
(32, 32, 2): [(b"ic12", read_png_or_jpeg2000)],
(48, 48, 1): [(b"ih32", read_32), (b"h8mk", read_mk)],
(32, 32, 1): [
(b"icp5", read_png_or_jpeg2000),
(b"il32", read_32),
(b"l8mk", read_mk),
],
(16, 16, 2): [(b"ic11", read_png_or_jpeg2000)],
(16, 16, 1): [
(b"icp4", read_png_or_jpeg2000),
(b"is32", read_32),
(b"s8mk", read_mk),
],
}
def __init__(self, fobj):
"""
fobj is a file-like object as an icns resource
"""
# signature : (start, length)
self.dct = dct = {}
self.fobj = fobj
sig, filesize = nextheader(fobj)
if sig != MAGIC:
raise SyntaxError("not an icns file")
i = HEADERSIZE
while i < filesize:
sig, blocksize = nextheader(fobj)
if blocksize <= 0:
raise SyntaxError("invalid block header")
i += HEADERSIZE
blocksize -= HEADERSIZE
dct[sig] = (i, blocksize)
fobj.seek(blocksize, io.SEEK_CUR)
i += blocksize
[文档] def itersizes(self):
sizes = []
for size, fmts in self.SIZES.items():
for (fmt, reader) in fmts:
if fmt in self.dct:
sizes.append(size)
break
return sizes
[文档] def bestsize(self):
sizes = self.itersizes()
if not sizes:
raise SyntaxError("No 32bit icon resources found")
return max(sizes)
[文档] def dataforsize(self, size):
"""
Get an icon resource as {channel: array}. Note that
the arrays are bottom-up like windows bitmaps and will likely
need to be flipped or transposed in some way.
"""
dct = {}
for code, reader in self.SIZES[size]:
desc = self.dct.get(code)
if desc is not None:
dct.update(reader(self.fobj, desc, size))
return dct
[文档] def getimage(self, size=None):
if size is None:
size = self.bestsize()
if len(size) == 2:
size = (size[0], size[1], 1)
channels = self.dataforsize(size)
im = channels.get("RGBA", None)
if im:
return im
im = channels.get("RGB").copy()
try:
im.putalpha(channels["A"])
except KeyError:
pass
return im
##
# Image plugin for Mac OS icons.
[文档]class IcnsImageFile(ImageFile.ImageFile):
"""
PIL image support for Mac OS .icns files.
Chooses the best resolution, but will possibly load
a different size image if you mutate the size attribute
before calling 'load'.
The info dictionary has a key 'sizes' that is a list
of sizes that the icns file has.
"""
format = "ICNS"
format_description = "Mac OS icns resource"
def _open(self):
self.icns = IcnsFile(self.fp)
self.mode = "RGBA"
self.info["sizes"] = self.icns.itersizes()
self.best_size = self.icns.bestsize()
self.size = (
self.best_size[0] * self.best_size[2],
self.best_size[1] * self.best_size[2],
)
@property
def size(self):
return self._size
@size.setter
def size(self, value):
info_size = value
if info_size not in self.info["sizes"] and len(info_size) == 2:
info_size = (info_size[0], info_size[1], 1)
if (
info_size not in self.info["sizes"]
and len(info_size) == 3
and info_size[2] == 1
):
simple_sizes = [
(size[0] * size[2], size[1] * size[2]) for size in self.info["sizes"]
]
if value in simple_sizes:
info_size = self.info["sizes"][simple_sizes.index(value)]
if info_size not in self.info["sizes"]:
raise ValueError("This is not one of the allowed sizes of this image")
self._size = value
[文档] def load(self):
if len(self.size) == 3:
self.best_size = self.size
self.size = (
self.best_size[0] * self.best_size[2],
self.best_size[1] * self.best_size[2],
)
Image.Image.load(self)
if self.im and self.im.size == self.size:
# Already loaded
return
self.load_prepare()
# This is likely NOT the best way to do it, but whatever.
im = self.icns.getimage(self.best_size)
# If this is a PNG or JPEG 2000, it won't be loaded yet
im.load()
self.im = im.im
self.mode = im.mode
self.size = im.size
self.load_end()
def _save(im, fp, filename):
"""
Saves the image as a series of PNG files,
that are then combined into a .icns file.
"""
if hasattr(fp, "flush"):
fp.flush()
sizes = {
b"ic07": 128,
b"ic08": 256,
b"ic09": 512,
b"ic10": 1024,
b"ic11": 32,
b"ic12": 64,
b"ic13": 256,
b"ic14": 512,
}
provided_images = {im.width: im for im in im.encoderinfo.get("append_images", [])}
size_streams = {}
for size in set(sizes.values()):
image = (
provided_images[size]
if size in provided_images
else im.resize((size, size))
)
temp = io.BytesIO()
image.save(temp, "png")
size_streams[size] = temp.getvalue()
entries = []
for type, size in sizes.items():
stream = size_streams[size]
entries.append({"type": type, "size": len(stream), "stream": stream})
# Header
fp.write(MAGIC)
fp.write(struct.pack(">i", sum(entry["size"] for entry in entries)))
# TOC
fp.write(b"TOC ")
fp.write(struct.pack(">i", HEADERSIZE + len(entries) * HEADERSIZE))
for entry in entries:
fp.write(entry["type"])
fp.write(struct.pack(">i", HEADERSIZE + entry["size"]))
# Data
for entry in entries:
fp.write(entry["type"])
fp.write(struct.pack(">i", HEADERSIZE + entry["size"]))
fp.write(entry["stream"])
if hasattr(fp, "flush"):
fp.flush()
def _accept(prefix):
return prefix[:4] == MAGIC
Image.register_open(IcnsImageFile.format, IcnsImageFile, _accept)
Image.register_extension(IcnsImageFile.format, ".icns")
Image.register_save(IcnsImageFile.format, _save)
Image.register_mime(IcnsImageFile.format, "image/icns")
if __name__ == "__main__":
if len(sys.argv) < 2:
print("Syntax: python3 IcnsImagePlugin.py [file]")
sys.exit()
with open(sys.argv[1], "rb") as fp:
imf = IcnsImageFile(fp)
for size in imf.info["sizes"]:
imf.size = size
imf.save("out-%s-%s-%s.png" % size)
with Image.open(sys.argv[1]) as im:
im.save("out.png")
if sys.platform == "windows":
os.startfile("out.png")
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