contrib/epstopng.py

   1 #!/usr/bin/env python
   2 #
   3 #
   4 # Copyright (C) 2003 André Wobst <wobsta@users.sourceforge.net>
   5 #
   6 # epstopng is free software; you can redistribute it and/or modify
   7 # it under the terms of the GNU General Public License as published by
   8 # the Free Software Foundation; either version 2 of the License, or
   9 # (at your option) any later version.
  10 #
  11 # epstopng is distributed in the hope that it will be useful,
  12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 # GNU General Public License for more details.
  15 #
  16 # You should have received a copy of the GNU General Public License
  17 # along with epstopng; if not, write to the Free Software
  18 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19
  20 # TODO: - set dpi in png (don't know how to do this in PIL)
  21 #       - this is much too slow --- consider a rewrite in C
  22
  23
  24 import getopt, sys, os, StringIO, re, math
  25 import Image # we use the python image library (PIL)
  26
  27
  28 progname = "epstopng v0.1: eps to transparent antialiased png converter"
  29
  30
  31 def epstopng(epsname, pngname, resolution, scale, transparent, gsname, quiet):
  32     sys.stderr.write("run ghostscript to create a %i times larger non-antialiased image ... " % scale)
  33     gsout = os.popen("%s -dEPSCrop -dNOPAUSE -dQUIET -dBATCH -sDEVICE=ppmraw -sOutputFile=- -r%i %s" % (gsname, resolution*scale, epsname))
  34     input = Image.open(StringIO.StringIO(gsout.read())).convert("RGB") # ensure rgb here
  35     output = Image.new("RGBA", [(x+scale-1)/scale for x in input.size])
  36     sys.stderr.write("done\n")
  37     sys.stderr.write("image size is %ix%i\n" % output.size)
  38
  39     inputdata = input.getdata() # getdata instead of getpixel leads to about a factor of 2 in running time
  40                                 # similar effect with putdata possible??? (didn't got that running)
  41     # loop over the small image
  42     for x in range(output.size[0]):
  43         sys.stderr.write("transparent antialias conversion ... %5.2f %%\r" % (x*100.0/output.size[0]))
  44         for y in range(output.size[1]):
  45             # r, g, b: sum of the rgb-values; u: number of non-transparent pixels
  46             r = g = b = u = 0
  47             # loop over the pixels of the large image to be used for pixel (x, y)
  48             for xo in range(x*scale, (x+1)*scale):
  49                 for yo in range(y*scale, (y+1)*scale):
  50                     if xo < input.size[0] and yo < input.size[1]:
  51                         ro, go, bo = inputdata[xo+input.size[0]*yo]
  52                         if (ro, go, bo) != transparent:
  53                             r += ro
  54                             g += go
  55                             b += bo
  56                             u += 1
  57             if u:
  58                 output.putpixel((x, y), (r/u, g/u, b/u, (u*255)/(scale*scale)))
  59             else:
  60                 output.putpixel((x, y), (255, 255, 255, 0))
  61     sys.stderr.write("transparent antialias conversion ... done     \n")
  62
  63     output.save(pngname)
  64
  65
  66 def usage():
  67     print progname
  68     print "Copyright (C) 2003 André Wobst <wobsta@users.sourceforge.net>"
  69     print "usage: epstopng [options] <eps-file>"
  70     print "-h, --help: show this help"
  71     print "-q, --quiet: be quiet"
  72     print "-o, --output <file>: output file name; must be set"
  73     print "-r, --resolution <dpi>: resolution; default: 100"
  74     print "-s, --scale <scale>: input scale for antialias; default: 4"
  75     print "-t, --transparent (<r>, <g>, <b>): transparent color; default: (255, 255, 255)"
  76     print "-g, --gsname <name>: name of the gs interpreter (gs version >= 8.0 needed!); default: \"gs\""
  77
  78
  79 def main():
  80     try:
  81         opts, args = getopt.getopt(sys.argv[1:], "hqo:r:s:t:g:", ["help", "quiet", "output", "resolution", "scale", "transparent", "gsname"])
  82     except getopt.GetoptError:
  83         # print help information and exit:
  84         usage()
  85         sys.exit(2)
  86     output = None
  87     resolution = 100
  88     scale = 4
  89     transparent = (255, 255, 255)
  90     gsname = "gs"
  91     quiet = 0
  92     for o, a in opts:
  93         if o in ("-h", "--help"):
  94             usage()
  95             sys.exit()
  96         if o in ("-o", "--output"):
  97             output = a
  98         if o in ("-r", "--resolution"):
  99             resolution = int(a)
 100         if o in ("-s", "--scale"):
 101             scale = int(a)
 102         if o in ("-t", "--transparent"):
 103             m = re.compile(r"\s*\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\)\s*$").match(a)
 104             if not m:
 105                 raise RuntimeError("transparent argument does not match")
 106             transparent = [int(x) for x in m.groups()]
 107         if o in ("-g", "--gsname"):
 108             gsname = a
 109     if len(args) == 1:
 110         input = args[0]
 111     elif len(args):
 112         raise RuntimeError("can't handle several input files")
 113     else:
 114         raise RuntimeError("must specify an input file (reading from stdin is not yet supported)")
 115     if output is None:
 116         raise RuntimeError("you must specify an output file name")
 117     if not quiet:
 118         sys.stderr.write(progname + "\n")
 119     epstopng(input, output, resolution, scale, transparent, gsname, quiet)
 120
 121
 122 if __name__ == "__main__":
 123     main()
 124