PIL.GbrImagePlugin 源代码

#
# The Python Imaging Library
#
# load a GIMP brush file
#
# History:
#       96-03-14 fl     Created
#       16-01-08 es     Version 2
#
# Copyright (c) Secret Labs AB 1997.
# Copyright (c) Fredrik Lundh 1996.
# Copyright (c) Eric Soroos 2016.
#
# See the README file for information on usage and redistribution.
#
#
# See https://github.com/GNOME/gimp/blob/master/devel-docs/gbr.txt for
# format documentation.
#
# This code Interprets version 1 and 2 .gbr files.
# Version 1 files are obsolete, and should not be used for new
#   brushes.
# Version 2 files are saved by GIMP v2.8 (at least)
# Version 3 files have a format specifier of 18 for 16bit floats in
#   the color depth field. This is currently unsupported by Pillow.

from PIL import Image, ImageFile, _binary

i32 = _binary.i32be


def _accept(prefix):
    return len(prefix) >= 8 and i32(prefix[:4]) >= 20 and i32(prefix[4:8]) in (1, 2)


##
# Image plugin for the GIMP brush format.

[文档]class GbrImageFile(ImageFile.ImageFile): format = "GBR" format_description = "GIMP brush file" def _open(self): header_size = i32(self.fp.read(4)) version = i32(self.fp.read(4)) if header_size < 20: raise SyntaxError("not a GIMP brush") if version not in (1, 2): raise SyntaxError("Unsupported GIMP brush version: %s" % version) width = i32(self.fp.read(4)) height = i32(self.fp.read(4)) color_depth = i32(self.fp.read(4)) if width <= 0 or height <= 0: raise SyntaxError("not a GIMP brush") if color_depth not in (1, 4): raise SyntaxError("Unsupported GIMP brush color depth: %s" % color_depth) if version == 1: comment_length = header_size-20 else: comment_length = header_size-28 magic_number = self.fp.read(4) if magic_number != b'GIMP': raise SyntaxError("not a GIMP brush, bad magic number") self.info['spacing'] = i32(self.fp.read(4)) comment = self.fp.read(comment_length)[:-1] if color_depth == 1: self.mode = "L" else: self.mode = 'RGBA' self.size = width, height self.info["comment"] = comment # Image might not be small Image._decompression_bomb_check(self.size) # Data is an uncompressed block of w * h * bytes/pixel self._data_size = width * height * color_depth
[文档] def load(self): self.im = Image.core.new(self.mode, self.size) self.frombytes(self.fp.read(self._data_size))
# # registry Image.register_open(GbrImageFile.format, GbrImageFile, _accept) Image.register_extension(GbrImageFile.format, ".gbr")