-
-
Notifications
You must be signed in to change notification settings - Fork 2.2k
/
SunImagePlugin.py
139 lines (112 loc) · 4.3 KB
/
SunImagePlugin.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
#
# The Python Imaging Library.
# $Id$
#
# Sun image file handling
#
# History:
# 1995-09-10 fl Created
# 1996-05-28 fl Fixed 32-bit alignment
# 1998-12-29 fl Import ImagePalette module
# 2001-12-18 fl Fixed palette loading (from Jean-Claude Rimbault)
#
# Copyright (c) 1997-2001 by Secret Labs AB
# Copyright (c) 1995-1996 by Fredrik Lundh
#
# See the README file for information on usage and redistribution.
#
from . import Image, ImageFile, ImagePalette
from ._binary import i32be as i32
def _accept(prefix):
return len(prefix) >= 4 and i32(prefix) == 0x59A66A95
##
# Image plugin for Sun raster files.
class SunImageFile(ImageFile.ImageFile):
format = "SUN"
format_description = "Sun Raster File"
def _open(self):
# The Sun Raster file header is 32 bytes in length
# and has the following format:
# typedef struct _SunRaster
# {
# DWORD MagicNumber; /* Magic (identification) number */
# DWORD Width; /* Width of image in pixels */
# DWORD Height; /* Height of image in pixels */
# DWORD Depth; /* Number of bits per pixel */
# DWORD Length; /* Size of image data in bytes */
# DWORD Type; /* Type of raster file */
# DWORD ColorMapType; /* Type of color map */
# DWORD ColorMapLength; /* Size of the color map in bytes */
# } SUNRASTER;
# HEAD
s = self.fp.read(32)
if not _accept(s):
msg = "not an SUN raster file"
raise SyntaxError(msg)
offset = 32
self._size = i32(s, 4), i32(s, 8)
depth = i32(s, 12)
# data_length = i32(s, 16) # unreliable, ignore.
file_type = i32(s, 20)
palette_type = i32(s, 24) # 0: None, 1: RGB, 2: Raw/arbitrary
palette_length = i32(s, 28)
if depth == 1:
self._mode, rawmode = "1", "1;I"
elif depth == 4:
self._mode, rawmode = "L", "L;4"
elif depth == 8:
self._mode = rawmode = "L"
elif depth == 24:
if file_type == 3:
self._mode, rawmode = "RGB", "RGB"
else:
self._mode, rawmode = "RGB", "BGR"
elif depth == 32:
if file_type == 3:
self._mode, rawmode = "RGB", "RGBX"
else:
self._mode, rawmode = "RGB", "BGRX"
else:
msg = "Unsupported Mode/Bit Depth"
raise SyntaxError(msg)
if palette_length:
if palette_length > 1024:
msg = "Unsupported Color Palette Length"
raise SyntaxError(msg)
if palette_type != 1:
msg = "Unsupported Palette Type"
raise SyntaxError(msg)
offset = offset + palette_length
self.palette = ImagePalette.raw("RGB;L", self.fp.read(palette_length))
if self.mode == "L":
self._mode = "P"
rawmode = rawmode.replace("L", "P")
# 16 bit boundaries on stride
stride = ((self.size[0] * depth + 15) // 16) * 2
# file type: Type is the version (or flavor) of the bitmap
# file. The following values are typically found in the Type
# field:
# 0000h Old
# 0001h Standard
# 0002h Byte-encoded
# 0003h RGB format
# 0004h TIFF format
# 0005h IFF format
# FFFFh Experimental
# Old and standard are the same, except for the length tag.
# byte-encoded is run-length-encoded
# RGB looks similar to standard, but RGB byte order
# TIFF and IFF mean that they were converted from T/IFF
# Experimental means that it's something else.
# (https://www.fileformat.info/format/sunraster/egff.htm)
if file_type in (0, 1, 3, 4, 5):
self.tile = [("raw", (0, 0) + self.size, offset, (rawmode, stride))]
elif file_type == 2:
self.tile = [("sun_rle", (0, 0) + self.size, offset, rawmode)]
else:
msg = "Unsupported Sun Raster file type"
raise SyntaxError(msg)
#
# registry
Image.register_open(SunImageFile.format, SunImageFile, _accept)
Image.register_extension(SunImageFile.format, ".ras")