Source code for PIL.McIdasImagePlugin

#
# The Python Imaging Library.
# $Id$
#
# Basic McIdas support for PIL
#
# History:
# 1997-05-05 fl  Created (8-bit images only)
# 2009-03-08 fl  Added 16/32-bit support.
#
# Thanks to Richard Jones and Craig Swank for specs and samples.
#
# Copyright (c) Secret Labs AB 1997.
# Copyright (c) Fredrik Lundh 1997.
#
# See the README file for information on usage and redistribution.
#

import struct
from . import Image, ImageFile

__version__ = "0.2"


def _accept(s):
    return s[:8] == b"\x00\x00\x00\x00\x00\x00\x00\x04"


##
# Image plugin for McIdas area images.

[docs]class McIdasImageFile(ImageFile.ImageFile): format = "MCIDAS" format_description = "McIdas area file" def _open(self): # parse area file directory s = self.fp.read(256) if not _accept(s) or len(s) != 256: raise SyntaxError("not an McIdas area file") self.area_descriptor_raw = s self.area_descriptor = w = [0] + list(struct.unpack("!64i", s)) # get mode if w[11] == 1: mode = rawmode = "L" elif w[11] == 2: # FIXME: add memory map support mode = "I" rawmode = "I;16B" elif w[11] == 4: # FIXME: add memory map support mode = "I" rawmode = "I;32B" else: raise SyntaxError("unsupported McIdas format") self.mode = mode self._size = w[10], w[9] offset = w[34] + w[15] stride = w[15] + w[10]*w[11]*w[14] self.tile = [("raw", (0, 0) + self.size, offset, (rawmode, stride, 1))]
# -------------------------------------------------------------------- # registry Image.register_open(McIdasImageFile.format, McIdasImageFile, _accept) # no default extension