Viewing file:  FpxImagePlugin.py (6.14 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
#
# THIS IS WORK IN PROGRESS
#
# The Python Imaging Library.
# $Id$
#
# FlashPix support for PIL
#
# History:
# 97-01-25 fl Created (reads uncompressed RGB images only)
#
# Copyright (c) Secret Labs AB 1997.
# Copyright (c) Fredrik Lundh 1997.
#
# See the README file for information on usage and redistribution.
#
from PIL import Image, ImageFile
from PIL.OleFileIO import i8, i32, MAGIC, OleFileIO
__version__ = "0.1"
# we map from colour field tuples to (mode, rawmode) descriptors
MODES = {
# opacity
(0x00007ffe): ("A", "L"),
# monochrome
(0x00010000,): ("L", "L"),
(0x00018000, 0x00017ffe): ("RGBA", "LA"),
# photo YCC
(0x00020000, 0x00020001, 0x00020002): ("RGB", "YCC;P"),
(0x00028000, 0x00028001, 0x00028002, 0x00027ffe): ("RGBA", "YCCA;P"),
# standard RGB (NIFRGB)
(0x00030000, 0x00030001, 0x00030002): ("RGB", "RGB"),
(0x00038000, 0x00038001, 0x00038002, 0x00037ffe): ("RGBA", "RGBA"),
}
#
# --------------------------------------------------------------------
def _accept(prefix):
return prefix[:8] == MAGIC
##
# Image plugin for the FlashPix images.
class FpxImageFile(ImageFile.ImageFile):
format = "FPX"
format_description = "FlashPix"
def _open(self):
#
# read the OLE directory and see if this is a likely
# to be a FlashPix file
try:
self.ole = OleFileIO(self.fp)
except IOError:
raise SyntaxError("not an FPX file; invalid OLE file")
if self.ole.root.clsid != "56616700-C154-11CE-8553-00AA00A1F95B":
raise SyntaxError("not an FPX file; bad root CLSID")
self._open_index(1)
def _open_index(self, index=1):
#
# get the Image Contents Property Set
prop = self.ole.getproperties([
"Data Object Store %06d" % index,
"\005Image Contents"
])
# size (highest resolution)
self.size = prop[0x1000002], prop[0x1000003]
size = max(self.size)
i = 1
while size > 64:
size = size / 2
i += 1
self.maxid = i - 1
# mode. instead of using a single field for this, flashpix
# requires you to specify the mode for each channel in each
# resolution subimage, and leaves it to the decoder to make
# sure that they all match. for now, we'll cheat and assume
# that this is always the case.
id = self.maxid << 16
s = prop[0x2000002 | id]
colors = []
for i in range(i32(s, 4)):
# note: for now, we ignore the "uncalibrated" flag
colors.append(i32(s, 8+i*4) & 0x7fffffff)
self.mode, self.rawmode = MODES[tuple(colors)]
# load JPEG tables, if any
self.jpeg = {}
for i in range(256):
id = 0x3000001 | (i << 16)
if id in prop:
self.jpeg[i] = prop[id]
# print len(self.jpeg), "tables loaded"
self._open_subimage(1, self.maxid)
def _open_subimage(self, index=1, subimage=0):
#
# setup tile descriptors for a given subimage
stream = [
"Data Object Store %06d" % index,
"Resolution %04d" % subimage,
"Subimage 0000 Header"
]
fp = self.ole.openstream(stream)
# skip prefix
fp.read(28)
# header stream
s = fp.read(36)
size = i32(s, 4), i32(s, 8)
# tilecount = i32(s, 12)
tilesize = i32(s, 16), i32(s, 20)
# channels = i32(s, 24)
offset = i32(s, 28)
length = i32(s, 32)
# print size, self.mode, self.rawmode
if size != self.size:
raise IOError("subimage mismatch")
# get tile descriptors
fp.seek(28 + offset)
s = fp.read(i32(s, 12) * length)
x = y = 0
xsize, ysize = size
xtile, ytile = tilesize
self.tile = []
for i in range(0, len(s), length):
compression = i32(s, i+8)
if compression == 0:
self.tile.append(("raw", (x, y, x+xtile, y+ytile),
i32(s, i) + 28, (self.rawmode)))
elif compression == 1:
# FIXME: the fill decoder is not implemented
self.tile.append(("fill", (x, y, x+xtile, y+ytile),
i32(s, i) + 28, (self.rawmode, s[12:16])))
elif compression == 2:
internal_color_conversion = i8(s[14])
jpeg_tables = i8(s[15])
rawmode = self.rawmode
if internal_color_conversion:
# The image is stored as usual (usually YCbCr).
if rawmode == "RGBA":
# For "RGBA", data is stored as YCbCrA based on
# negative RGB. The following trick works around
# this problem :
jpegmode, rawmode = "YCbCrK", "CMYK"
else:
jpegmode = None # let the decoder decide
else:
# The image is stored as defined by rawmode
jpegmode = rawmode
self.tile.append(("jpeg", (x, y, x+xtile, y+ytile),
i32(s, i) + 28, (rawmode, jpegmode)))
# FIXME: jpeg tables are tile dependent; the prefix
# data must be placed in the tile descriptor itself!
if jpeg_tables:
self.tile_prefix = self.jpeg[jpeg_tables]
else:
raise IOError("unknown/invalid compression")
x = x + xtile
if x >= xsize:
x, y = 0, y + ytile
if y >= ysize:
break # isn't really required
self.stream = stream
self.fp = None
def load(self):
if not self.fp:
self.fp = self.ole.openstream(self.stream[:2] +
["Subimage 0000 Data"])
ImageFile.ImageFile.load(self)
#
# --------------------------------------------------------------------
Image.register_open("FPX", FpxImageFile, _accept)
Image.register_extension("FPX", ".fpx")
|