Pillow/PIL/McIdasImagePlugin.py
Brian Crowell a7e3b2e47b py3k: The big push
There are two main issues fixed with this commit:

* bytes vs. str: All file, image, and palette data are now handled as
  bytes. A new _binary module consolidates the hacks needed to do this
  across Python versions. tostring/fromstring methods have been renamed to
  tobytes/frombytes, but the Python 2.6/2.7 versions alias them to the old
  names for compatibility. Users should move to tobytes/frombytes.

  One other potentially-breaking change is that text data in image files
  (such as tags, comments) are now explicitly handled with a specific
  character encoding in mind. This works well with the Unicode str in
  Python 3, but may trip up old code expecting a straight byte-for-byte
  translation to a Python string. This also required a change to Gohlke's
  tags tests (in Tests/test_file_png.py) to expect Unicode strings from
  the code.

* True div vs. floor div: Many division operations used the "/" operator
  to do floor division, which is now the "//" operator in Python 3. These
  were fixed.

As of this commit, on the first pass, I have one failing test (improper
handling of a slice object in a C module, test_imagepath.py) in Python 3,
and three that that I haven't tried running yet (test_imagegl,
test_imagegrab, and test_imageqt). I also haven't tested anything on
Windows. All but the three skipped tests run flawlessly against Pythons
2.6 and 2.7.
2013-01-10 08:46:56 -06:00

71 lines
1.7 KiB
Python

#
# 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.
#
__version__ = "0.2"
import struct
from . import Image, ImageFile
def _accept(s):
return s[:8] == b"\x00\x00\x00\x00\x00\x00\x00\x04"
##
# Image plugin for McIdas area images.
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("MCIDAS", McIdasImageFile, _accept)
# no default extension