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Diffstat (limited to 'lib/Python/Lib/PIL/PpmImagePlugin.py')
-rw-r--r-- | lib/Python/Lib/PIL/PpmImagePlugin.py | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/lib/Python/Lib/PIL/PpmImagePlugin.py b/lib/Python/Lib/PIL/PpmImagePlugin.py new file mode 100644 index 000000000..954832451 --- /dev/null +++ b/lib/Python/Lib/PIL/PpmImagePlugin.py @@ -0,0 +1,172 @@ +# +# The Python Imaging Library. +# $Id$ +# +# PPM support for PIL +# +# History: +# 96-03-24 fl Created +# 98-03-06 fl Write RGBA images (as RGB, that is) +# +# Copyright (c) Secret Labs AB 1997-98. +# Copyright (c) Fredrik Lundh 1996. +# +# See the README file for information on usage and redistribution. +# + + +__version__ = "0.2" + +import string + +from PIL import Image, ImageFile + +# +# -------------------------------------------------------------------- + +b_whitespace = string.whitespace +try: + import locale + locale_lang, locale_enc = locale.getlocale() + if locale_enc is None: + locale_lang, locale_enc = locale.getdefaultlocale() + b_whitespace = b_whitespace.decode(locale_enc) +except: + pass +b_whitespace = b_whitespace.encode('ascii', 'ignore') + +MODES = { + # standard + b"P4": "1", + b"P5": "L", + b"P6": "RGB", + # extensions + b"P0CMYK": "CMYK", + # PIL extensions (for test purposes only) + b"PyP": "P", + b"PyRGBA": "RGBA", + b"PyCMYK": "CMYK" +} + + +def _accept(prefix): + return prefix[0:1] == b"P" and prefix[1] in b"0456y" + + +## +# Image plugin for PBM, PGM, and PPM images. + +class PpmImageFile(ImageFile.ImageFile): + + format = "PPM" + format_description = "Pbmplus image" + + def _token(self, s=b""): + while True: # read until next whitespace + c = self.fp.read(1) + if not c or c in b_whitespace: + break + if c > b'\x79': + raise ValueError("Expected ASCII value, found binary") + s = s + c + if (len(s) > 9): + raise ValueError("Expected int, got > 9 digits") + return s + + def _open(self): + + # check magic + s = self.fp.read(1) + if s != b"P": + raise SyntaxError("not a PPM file") + mode = MODES[self._token(s)] + + if mode == "1": + self.mode = "1" + rawmode = "1;I" + else: + self.mode = rawmode = mode + + for ix in range(3): + while True: + while True: + s = self.fp.read(1) + if s not in b_whitespace: + break + if s != b"#": + break + s = self.fp.readline() + s = int(self._token(s)) + if ix == 0: + xsize = s + elif ix == 1: + ysize = s + if mode == "1": + break + elif ix == 2: + # maxgrey + if s > 255: + if not mode == 'L': + raise ValueError("Too many colors for band: %s" % s) + if s < 2**16: + self.mode = 'I' + rawmode = 'I;16B' + else: + self.mode = 'I' + rawmode = 'I;32B' + + self.size = xsize, ysize + self.tile = [("raw", + (0, 0, xsize, ysize), + self.fp.tell(), + (rawmode, 0, 1))] + + # ALTERNATIVE: load via builtin debug function + # self.im = Image.core.open_ppm(self.filename) + # self.mode = self.im.mode + # self.size = self.im.size + + +# +# -------------------------------------------------------------------- + +def _save(im, fp, filename): + if im.mode == "1": + rawmode, head = "1;I", b"P4" + elif im.mode == "L": + rawmode, head = "L", b"P5" + elif im.mode == "I": + if im.getextrema()[1] < 2**16: + rawmode, head = "I;16B", b"P5" + else: + rawmode, head = "I;32B", b"P5" + elif im.mode == "RGB": + rawmode, head = "RGB", b"P6" + elif im.mode == "RGBA": + rawmode, head = "RGB", b"P6" + else: + raise IOError("cannot write mode %s as PPM" % im.mode) + fp.write(head + ("\n%d %d\n" % im.size).encode('ascii')) + if head == b"P6": + fp.write(b"255\n") + if head == b"P5": + if rawmode == "L": + fp.write(b"255\n") + elif rawmode == "I;16B": + fp.write(b"65535\n") + elif rawmode == "I;32B": + fp.write(b"2147483648\n") + ImageFile._save(im, fp, [("raw", (0, 0)+im.size, 0, (rawmode, 0, 1))]) + + # ALTERNATIVE: save via builtin debug function + # im._dump(filename) + +# +# -------------------------------------------------------------------- + +Image.register_open("PPM", PpmImageFile, _accept) +Image.register_save("PPM", _save) + +Image.register_extension("PPM", ".pbm") +Image.register_extension("PPM", ".pgm") +Image.register_extension("PPM", ".ppm") |