Source code for PIL.TgaImagePlugin

#
# 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.

[docs]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")