Source code for PIL.FitsStubImagePlugin

#
# The Python Imaging Library
# $Id$
#
# FITS stub adapter
#
# Copyright (c) 1998-2003 by Fredrik Lundh
#
# See the README file for information on usage and redistribution.
#

from . import Image, ImageFile

_handler = None


[docs]def register_handler(handler): """ Install application-specific FITS image handler. :param handler: Handler object. """ global _handler _handler = handler
# -------------------------------------------------------------------- # Image adapter def _accept(prefix): return prefix[:6] == b"SIMPLE"
[docs]class FITSStubImageFile(ImageFile.StubImageFile): format = "FITS" format_description = "FITS" def _open(self): offset = self.fp.tell() headers = {} while True: header = self.fp.read(80) if not header: raise OSError("Truncated FITS file") keyword = header[:8].strip() if keyword == b"END": break value = header[8:].strip() if value.startswith(b"="): value = value[1:].strip() if not headers and (not _accept(keyword) or value != b"T"): raise SyntaxError("Not a FITS file") headers[keyword] = value naxis = int(headers[b"NAXIS"]) if naxis == 0: raise ValueError("No image data") elif naxis == 1: self._size = 1, int(headers[b"NAXIS1"]) else: self._size = int(headers[b"NAXIS1"]), int(headers[b"NAXIS2"]) number_of_bits = int(headers[b"BITPIX"]) if number_of_bits == 8: self.mode = "L" elif number_of_bits == 16: self.mode = "I" # rawmode = "I;16S" elif number_of_bits == 32: self.mode = "I" elif number_of_bits in (-32, -64): self.mode = "F" # rawmode = "F" if number_of_bits == -32 else "F;64F" self.fp.seek(offset) loader = self._load() if loader: loader.open(self) def _load(self): return _handler
def _save(im, fp, filename): if _handler is None or not hasattr("_handler", "save"): raise OSError("FITS save handler not installed") _handler.save(im, fp, filename) # -------------------------------------------------------------------- # Registry Image.register_open(FITSStubImageFile.format, FITSStubImageFile, _accept) Image.register_save(FITSStubImageFile.format, _save) Image.register_extensions(FITSStubImageFile.format, [".fit", ".fits"])