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- #
- # 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")
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