#
# The Python Imaging Library.
# $Id$
#
# Mac OS X icns file decoder, based on icns.py by Bob Ippolito.
#
# history:
# 2004-10-09 fl Turned into a PIL plugin; removed 2.3 dependencies.
#
# Copyright (c) 2004 by Bob Ippolito.
# Copyright (c) 2004 by Secret Labs.
# Copyright (c) 2004 by Fredrik Lundh.
#
# See the README file for information on usage and redistribution.
#
import Image, ImageFile
import string, struct
HEADERSIZE = 8
def nextheader(fobj):
return struct.unpack('>4sI', fobj.read(HEADERSIZE))
def read_32t(fobj, (start, length), (width, height)):
# The 128x128 icon seems to have an extra header for some reason.
fobj.seek(start)
sig = fobj.read(4)
if sig != '\x00\x00\x00\x00':
raise SyntaxError, 'Unknown signature, expecting 0x00000000'
return read_32(fobj, (start + 4, length - 4), (width, height))
def read_32(fobj, (start, length), size):
"""
Read a 32bit RGB icon resource. Seems to be either uncompressed or
an RLE packbits-like scheme.
"""
fobj.seek(start)
sizesq = size[0] * size[1]
if length == sizesq * 3:
# uncompressed ("RGBRGBGB")
indata = fobj.read(length)
im = Image.frombuffer("RGB", size, indata, "raw", "RGB", 0, 1)
else:
# decode image
im = Image.new("RGB", size, None)
for band_ix in range(3):
data = []
bytesleft = sizesq
while bytesleft > 0:
byte = fobj.read(1)
if not byte:
break
byte = ord(byte)
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 = bytesleft - blocksize
if bytesleft <= 0:
break
if bytesleft != 0:
raise SyntaxError(
"Error reading channel [%r left]" % bytesleft
)
band = Image.frombuffer(
"L", size, string.join(data, ""), "raw", "L", 0, 1
)
im.im.putband(band.im, band_ix)
return {"RGB": im}
def read_mk(fobj, (start, length), size):
# Alpha masks seem to be uncompressed
fobj.seek(start)
band = Image.frombuffer(
"L", size, fobj.read(size[0]*size[1]), "raw", "L", 0, 1
)
return {"A": band}
class IcnsFile:
SIZES = {
(128, 128): [
('it32', read_32t),
('t8mk', read_mk),
],
(48, 48): [
('ih32', read_32),
('h8mk', read_mk),
],
(32, 32): [
('il32', read_32),
('l8mk', read_mk),
],
(16, 16): [
('is32', read_32),
('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 != 'icns':
raise SyntaxError, 'not an icns file'
i = HEADERSIZE
while i < filesize:
sig, blocksize = nextheader(fobj)
i = i + HEADERSIZE
blocksize = blocksize - HEADERSIZE
dct[sig] = (i, blocksize)
fobj.seek(blocksize, 1)
i = i + blocksize
def itersizes(self):
sizes = []
for size, fmts in self.SIZES.items():
for (fmt, reader) in fmts:
if self.dct.has_key(fmt):
sizes.append(size)
break
return sizes
def bestsize(self):
sizes = self.itersizes()
if not sizes:
raise SyntaxError, "No 32bit icon resources found"
return max(sizes)
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
def getimage(self, size=None):
if size is None:
size = self.bestsize()
channels = self.dataforsize(size)
im = channels.get("RGB").copy()
try:
im.putalpha(channels["A"])
except KeyError:
pass
return im
##
# Image plugin for Mac OS icons.
class IcnsImageFile(ImageFile.ImageFile):
"""
PIL read-only 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.size = self.icns.bestsize()
self.info['sizes'] = self.icns.itersizes()
# Just use this to see if it's loaded or not yet.
self.tile = ('',)
def load(self):
Image.Image.load(self)
if not self.tile:
return
self.load_prepare()
# This is likely NOT the best way to do it, but whatever.
im = self.icns.getimage(self.size)
self.im = im.im
self.mode = im.mode
self.size = im.size
self.fp = None
self.icns = None
self.tile = ()
self.load_end()
Image.register_open("ICNS", IcnsImageFile, lambda x: x[:4] == 'icns')
Image.register_extension("ICNS", '.icns')
if __name__ == '__main__':
import os, sys
im = Image.open(open(sys.argv[1], "rb"))
im.save("out.png")
os.startfile("out.png")
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