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Diffstat (limited to 'lib/Python/Lib/PIL/ImagePalette.py')
| -rw-r--r-- | lib/Python/Lib/PIL/ImagePalette.py | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/lib/Python/Lib/PIL/ImagePalette.py b/lib/Python/Lib/PIL/ImagePalette.py new file mode 100644 index 000000000..62f8814f1 --- /dev/null +++ b/lib/Python/Lib/PIL/ImagePalette.py @@ -0,0 +1,235 @@ +# +# The Python Imaging Library. +# $Id$ +# +# image palette object +# +# History: +# 1996-03-11 fl Rewritten. +# 1997-01-03 fl Up and running. +# 1997-08-23 fl Added load hack +# 2001-04-16 fl Fixed randint shadow bug in random() +# +# Copyright (c) 1997-2001 by Secret Labs AB +# Copyright (c) 1996-1997 by Fredrik Lundh +# +# See the README file for information on usage and redistribution. +# + +import array +import warnings +from PIL import ImageColor + + +class ImagePalette: + "Color palette for palette mapped images" + + def __init__(self, mode="RGB", palette=None, size=0): + self.mode = mode + self.rawmode = None # if set, palette contains raw data + self.palette = palette or list(range(256))*len(self.mode) + self.colors = {} + self.dirty = None + if ((size == 0 and len(self.mode)*256 != len(self.palette)) or + (size != 0 and size != len(self.palette))): + raise ValueError("wrong palette size") + + def getdata(self): + """ + Get palette contents in format suitable # for the low-level + ``im.putpalette`` primitive. + + .. warning:: This method is experimental. + """ + if self.rawmode: + return self.rawmode, self.palette + return self.mode + ";L", self.tobytes() + + def tobytes(self): + """Convert palette to bytes. + + .. warning:: This method is experimental. + """ + if self.rawmode: + raise ValueError("palette contains raw palette data") + if isinstance(self.palette, bytes): + return self.palette + arr = array.array("B", self.palette) + if hasattr(arr, 'tobytes'): + # py3k has a tobytes, tostring is deprecated. + return arr.tobytes() + return arr.tostring() + + # Declare tostring as an alias for tobytes + tostring = tobytes + + def getcolor(self, color): + """Given an rgb tuple, allocate palette entry. + + .. warning:: This method is experimental. + """ + if self.rawmode: + raise ValueError("palette contains raw palette data") + if isinstance(color, tuple): + try: + return self.colors[color] + except KeyError: + # allocate new color slot + if isinstance(self.palette, bytes): + self.palette = [int(x) for x in self.palette] + index = len(self.colors) + if index >= 256: + raise ValueError("cannot allocate more than 256 colors") + self.colors[color] = index + self.palette[index] = color[0] + self.palette[index+256] = color[1] + self.palette[index+512] = color[2] + self.dirty = 1 + return index + else: + raise ValueError("unknown color specifier: %r" % color) + + def save(self, fp): + """Save palette to text file. + + .. warning:: This method is experimental. + """ + if self.rawmode: + raise ValueError("palette contains raw palette data") + if isinstance(fp, str): + fp = open(fp, "w") + fp.write("# Palette\n") + fp.write("# Mode: %s\n" % self.mode) + for i in range(256): + fp.write("%d" % i) + for j in range(i*len(self.mode), (i+1)*len(self.mode)): + try: + fp.write(" %d" % self.palette[j]) + except IndexError: + fp.write(" 0") + fp.write("\n") + fp.close() + + +# -------------------------------------------------------------------- +# Internal + +def raw(rawmode, data): + palette = ImagePalette() + palette.rawmode = rawmode + palette.palette = data + palette.dirty = 1 + return palette + + +# -------------------------------------------------------------------- +# Factories + +def _make_linear_lut(black, white): + warnings.warn( + '_make_linear_lut() is deprecated. ' + 'Please call make_linear_lut() instead.', + DeprecationWarning, + stacklevel=2 + ) + return make_linear_lut(black, white) + + +def _make_gamma_lut(exp): + warnings.warn( + '_make_gamma_lut() is deprecated. ' + 'Please call make_gamma_lut() instead.', + DeprecationWarning, + stacklevel=2 + ) + return make_gamma_lut(exp) + + +def make_linear_lut(black, white): + lut = [] + if black == 0: + for i in range(256): + lut.append(white*i//255) + else: + raise NotImplementedError # FIXME + return lut + + +def make_gamma_lut(exp): + lut = [] + for i in range(256): + lut.append(int(((i / 255.0) ** exp) * 255.0 + 0.5)) + return lut + + +def negative(mode="RGB"): + palette = list(range(256)) + palette.reverse() + return ImagePalette(mode, palette * len(mode)) + + +def random(mode="RGB"): + from random import randint + palette = [] + for i in range(256*len(mode)): + palette.append(randint(0, 255)) + return ImagePalette(mode, palette) + + +def sepia(white="#fff0c0"): + r, g, b = ImageColor.getrgb(white) + r = make_linear_lut(0, r) + g = make_linear_lut(0, g) + b = make_linear_lut(0, b) + return ImagePalette("RGB", r + g + b) + + +def wedge(mode="RGB"): + return ImagePalette(mode, list(range(256)) * len(mode)) + + +def load(filename): + + # FIXME: supports GIMP gradients only + + fp = open(filename, "rb") + + lut = None + + if not lut: + try: + from PIL import GimpPaletteFile + fp.seek(0) + p = GimpPaletteFile.GimpPaletteFile(fp) + lut = p.getpalette() + except (SyntaxError, ValueError): + # import traceback + # traceback.print_exc() + pass + + if not lut: + try: + from PIL import GimpGradientFile + fp.seek(0) + p = GimpGradientFile.GimpGradientFile(fp) + lut = p.getpalette() + except (SyntaxError, ValueError): + # import traceback + # traceback.print_exc() + pass + + if not lut: + try: + from PIL import PaletteFile + fp.seek(0) + p = PaletteFile.PaletteFile(fp) + lut = p.getpalette() + except (SyntaxError, ValueError): + import traceback + traceback.print_exc() + pass + + if not lut: + raise IOError("cannot load palette") + + return lut # data, rawmode |