Source code for PIL.FpxImagePlugin

#
# 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 __future__ import annotations

import olefile

from . import Image, ImageFile
from ._binary import i32le as i32

# 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] == olefile.MAGIC


##
# Image plugin for the FlashPix images.


[docs] 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 = olefile.OleFileIO(self.fp) except OSError as e: msg = "not an FPX file; invalid OLE file" raise SyntaxError(msg) from e if self.ole.root.clsid != "56616700-C154-11CE-8553-00AA00A1F95B": msg = "not an FPX file; bad root CLSID" raise SyntaxError(msg) self._open_index(1) def _open_index(self, index=1): # # get the Image Contents Property Set prop = self.ole.getproperties( [f"Data Object Store {index:06d}", "\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] bands = i32(s, 4) if bands > 4: msg = "Invalid number of bands" raise OSError(msg) # note: for now, we ignore the "uncalibrated" flag colors = tuple(i32(s, 8 + i * 4) & 0x7FFFFFFF for i in range(bands)) self._mode, self.rawmode = MODES[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] self._open_subimage(1, self.maxid) def _open_subimage(self, index=1, subimage=0): # # setup tile descriptors for a given subimage stream = [ f"Data Object Store {index:06d}", f"Resolution {subimage:04d}", "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) if size != self.size: msg = "subimage mismatch" raise OSError(msg) # 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): x1 = min(xsize, x + xtile) y1 = min(ysize, y + ytile) compression = i32(s, i + 8) if compression == 0: self.tile.append( ( "raw", (x, y, x1, y1), i32(s, i) + 28, (self.rawmode,), ) ) elif compression == 1: # FIXME: the fill decoder is not implemented self.tile.append( ( "fill", (x, y, x1, y1), i32(s, i) + 28, (self.rawmode, s[12:16]), ) ) elif compression == 2: internal_color_conversion = s[14] jpeg_tables = 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, x1, y1), 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: msg = "unknown/invalid compression" raise OSError(msg) x = x + xtile if x >= xsize: x, y = 0, y + ytile if y >= ysize: break # isn't really required self.stream = stream self._fp = self.fp self.fp = None
[docs] def load(self): if not self.fp: self.fp = self.ole.openstream(self.stream[:2] + ["Subimage 0000 Data"]) return ImageFile.ImageFile.load(self)
[docs] def close(self): self.ole.close() super().close()
def __exit__(self, *args): self.ole.close() super().__exit__()
# # -------------------------------------------------------------------- Image.register_open(FpxImageFile.format, FpxImageFile, _accept) Image.register_extension(FpxImageFile.format, ".fpx")