codekingpro/portable-devtools

1#
2# The Python Imaging Library
3# $Id$
4#
5# HDF5 stub adapter
6#
7# Copyright (c) 2000-2003 by Fredrik Lundh
8#
9# See the README file for information on usage and redistribution.
10#
11from __future__ import annotations
12
13import os
14from typing import IO
15
16from . import Image, ImageFile
17
18_handler = None
19
20
21def register_handler(handler: ImageFile.StubHandler | None) -> None:
22    """
23    Install application-specific HDF5 image handler.
24
25    :param handler: Handler object.
26    """
27    global _handler
28    _handler = handler
29
30
31# --------------------------------------------------------------------
32# Image adapter
33
34
35def _accept(prefix: bytes) -> bool:
36    return prefix.startswith(b"\x89HDF\r\n\x1a\n")
37
38
39class HDF5StubImageFile(ImageFile.StubImageFile):
40    format = "HDF5"
41    format_description = "HDF5"
42
43    def _open(self) -> None:
44        assert self.fp is not None
45        if not _accept(self.fp.read(8)):
46            msg = "Not an HDF file"
47            raise SyntaxError(msg)
48
49        self.fp.seek(-8, os.SEEK_CUR)
50
51        # make something up
52        self._mode = "F"
53        self._size = 1, 1
54
55    def _load(self) -> ImageFile.StubHandler | None:
56        return _handler
57
58
59def _save(im: Image.Image, fp: IO[bytes], filename: str | bytes) -> None:
60    if _handler is None or not hasattr(_handler, "save"):
61        msg = "HDF5 save handler not installed"
62        raise OSError(msg)
63    _handler.save(im, fp, filename)
64
65
66# --------------------------------------------------------------------
67# Registry
68
69Image.register_open(HDF5StubImageFile.format, HDF5StubImageFile, _accept)
70Image.register_save(HDF5StubImageFile.format, _save)
71
72Image.register_extensions(HDF5StubImageFile.format, [".h5", ".hdf"])
73