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- #
- # The Python Imaging Library.
- # $Id$
- #
- # TGA file handling
- #
- # History:
- # 95-09-01 fl created (reads 24-bit files only)
- # 97-01-04 fl support more TGA versions, including compressed images
- # 98-07-04 fl fixed orientation and alpha layer bugs
- # 98-09-11 fl fixed orientation for runlength decoder
- #
- # Copyright (c) Secret Labs AB 1997-98.
- # Copyright (c) Fredrik Lundh 1995-97.
- #
- # See the README file for information on usage and redistribution.
- #
-
-
- from . import Image, ImageFile, ImagePalette
- from ._binary import i8, i16le as i16, o8, o16le as o16
-
- import warnings
-
- __version__ = "0.3"
-
-
- #
- # --------------------------------------------------------------------
- # Read RGA file
-
-
- MODES = {
- # map imagetype/depth to rawmode
- (1, 8): "P",
- (3, 1): "1",
- (3, 8): "L",
- (3, 16): "LA",
- (2, 16): "BGR;5",
- (2, 24): "BGR",
- (2, 32): "BGRA",
- }
-
-
- ##
- # Image plugin for Targa files.
-
- class TgaImageFile(ImageFile.ImageFile):
-
- format = "TGA"
- format_description = "Targa"
-
- def _open(self):
-
- # process header
- s = self.fp.read(18)
-
- id_len = i8(s[0])
-
- colormaptype = i8(s[1])
- imagetype = i8(s[2])
-
- depth = i8(s[16])
-
- flags = i8(s[17])
-
- self._size = i16(s[12:]), i16(s[14:])
-
- # validate header fields
- if colormaptype not in (0, 1) or\
- self.size[0] <= 0 or self.size[1] <= 0 or\
- depth not in (1, 8, 16, 24, 32):
- raise SyntaxError("not a TGA file")
-
- # image mode
- if imagetype in (3, 11):
- self.mode = "L"
- if depth == 1:
- self.mode = "1" # ???
- elif depth == 16:
- self.mode = "LA"
- elif imagetype in (1, 9):
- self.mode = "P"
- elif imagetype in (2, 10):
- self.mode = "RGB"
- if depth == 32:
- self.mode = "RGBA"
- else:
- raise SyntaxError("unknown TGA mode")
-
- # orientation
- orientation = flags & 0x30
- if orientation == 0x20:
- orientation = 1
- elif not orientation:
- orientation = -1
- else:
- raise SyntaxError("unknown TGA orientation")
-
- self.info["orientation"] = orientation
-
- if imagetype & 8:
- self.info["compression"] = "tga_rle"
-
- if id_len:
- self.info["id_section"] = self.fp.read(id_len)
-
- if colormaptype:
- # read palette
- start, size, mapdepth = i16(s[3:]), i16(s[5:]), i16(s[7:])
- if mapdepth == 16:
- self.palette = ImagePalette.raw(
- "BGR;16", b"\0"*2*start + self.fp.read(2*size))
- elif mapdepth == 24:
- self.palette = ImagePalette.raw(
- "BGR", b"\0"*3*start + self.fp.read(3*size))
- elif mapdepth == 32:
- self.palette = ImagePalette.raw(
- "BGRA", b"\0"*4*start + self.fp.read(4*size))
-
- # setup tile descriptor
- try:
- rawmode = MODES[(imagetype & 7, depth)]
- if imagetype & 8:
- # compressed
- self.tile = [("tga_rle", (0, 0)+self.size,
- self.fp.tell(), (rawmode, orientation, depth))]
- else:
- self.tile = [("raw", (0, 0)+self.size,
- self.fp.tell(), (rawmode, 0, orientation))]
- except KeyError:
- pass # cannot decode
-
- #
- # --------------------------------------------------------------------
- # Write TGA file
-
-
- SAVE = {
- "1": ("1", 1, 0, 3),
- "L": ("L", 8, 0, 3),
- "LA": ("LA", 16, 0, 3),
- "P": ("P", 8, 1, 1),
- "RGB": ("BGR", 24, 0, 2),
- "RGBA": ("BGRA", 32, 0, 2),
- }
-
-
- def _save(im, fp, filename):
-
- try:
- rawmode, bits, colormaptype, imagetype = SAVE[im.mode]
- except KeyError:
- raise IOError("cannot write mode %s as TGA" % im.mode)
-
- if "rle" in im.encoderinfo:
- rle = im.encoderinfo["rle"]
- else:
- compression = im.encoderinfo.get("compression",
- im.info.get("compression"))
- rle = compression == "tga_rle"
- if rle:
- imagetype += 8
-
- id_section = im.encoderinfo.get("id_section",
- im.info.get("id_section", ""))
- id_len = len(id_section)
- if id_len > 255:
- id_len = 255
- id_section = id_section[:255]
- warnings.warn("id_section has been trimmed to 255 characters")
-
- if colormaptype:
- colormapfirst, colormaplength, colormapentry = 0, 256, 24
- else:
- colormapfirst, colormaplength, colormapentry = 0, 0, 0
-
- if im.mode in ("LA", "RGBA"):
- flags = 8
- else:
- flags = 0
-
- orientation = im.encoderinfo.get("orientation",
- im.info.get("orientation", -1))
- if orientation > 0:
- flags = flags | 0x20
-
- fp.write(o8(id_len) +
- o8(colormaptype) +
- o8(imagetype) +
- o16(colormapfirst) +
- o16(colormaplength) +
- o8(colormapentry) +
- o16(0) +
- o16(0) +
- o16(im.size[0]) +
- o16(im.size[1]) +
- o8(bits) +
- o8(flags))
-
- if id_section:
- fp.write(id_section)
-
- if colormaptype:
- fp.write(im.im.getpalette("RGB", "BGR"))
-
- if rle:
- ImageFile._save(
- im,
- fp,
- [("tga_rle", (0, 0) + im.size, 0, (rawmode, orientation))])
- else:
- ImageFile._save(
- im, fp, [("raw", (0, 0) + im.size, 0, (rawmode, 0, orientation))])
-
- # write targa version 2 footer
- fp.write(b"\000" * 8 + b"TRUEVISION-XFILE." + b"\000")
-
- #
- # --------------------------------------------------------------------
- # Registry
-
-
- Image.register_open(TgaImageFile.format, TgaImageFile)
- Image.register_save(TgaImageFile.format, _save)
-
- Image.register_extension(TgaImageFile.format, ".tga")
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