#
# The Python Imaging Library.
# $Id$
#
# EPS file handling
#
# History:
# 1995-09-01 fl Created (0.1)
# 1996-05-18 fl Don't choke on "atend" fields, Ghostscript interface (0.2)
# 1996-08-22 fl Don't choke on floating point BoundingBox values
# 1996-08-23 fl Handle files from Macintosh (0.3)
# 2001-02-17 fl Use 're' instead of 'regex' (Python 2.1) (0.4)
# 2003-09-07 fl Check gs.close status (from Federico Di Gregorio) (0.5)
#
# Copyright (c) 1997-2003 by Secret Labs AB.
# Copyright (c) 1995-2003 by Fredrik Lundh
#
# See the README file for information on usage and redistribution.
#
__version__ = "0.5"
import re, string
import Image, ImageFile
#
# --------------------------------------------------------------------
def i32(c):
return ord(c[0]) + (ord(c[1])<<8) + (ord(c[2])<<16) + (ord(c[3])<<24)
def o32(i):
return chr(i&255) + chr(i>>8&255) + chr(i>>16&255) + chr(i>>24&255)
split = re.compile(r"^%%([^:]*):[ \t]*(.*)[ \t]*$")
field = re.compile(r"^%[%!\w]([^:]*)[ \t]*$")
def Ghostscript(tile, size, fp):
"""Render an image using Ghostscript (Unix only)"""
# Unpack decoder tile
decoder, tile, offset, data = tile[0]
length, bbox = data
import tempfile, os
file = tempfile.mktemp()
# Build ghostscript command
command = ["gs",
"-q", # quite mode
"-g%dx%d" % size, # set output geometry (pixels)
"-dNOPAUSE -dSAFER", # don't pause between pages, safe mode
"-sDEVICE=ppmraw", # ppm driver
"-sOutputFile=%s" % file,# output file
"- >/dev/null 2>/dev/null"]
command = string.join(command)
# push data through ghostscript
try:
gs = os.popen(command, "w")
# adjust for image origin
if bbox[0] != 0 or bbox[1] != 0:
gs.write("%d %d translate\n" % (-bbox[0], -bbox[1]))
fp.seek(offset)
while length > 0:
s = fp.read(8192)
if not s:
break
length = length - len(s)
gs.write(s)
status = gs.close()
if status:
raise IOError("gs failed (status %d)" % status)
im = Image.core.open_ppm(file)
finally:
try: os.unlink(file)
except: pass
return im
class PSFile:
"""Wrapper that treats either CR or LF as end of line."""
def __init__(self, fp):
self.fp = fp
self.char = None
def __getattr__(self, id):
v = getattr(self.fp, id)
setattr(self, id, v)
return v
def seek(self, offset, whence=0):
self.char = None
self.fp.seek(offset, whence)
def tell(self):
pos = self.fp.tell()
if self.char:
pos = pos - 1
return pos
def readline(self):
s = ""
if self.char:
c = self.char
self.char = None
else:
c = self.fp.read(1)
while c not in "\r\n":
s = s + c
c = self.fp.read(1)
if c == "\r":
self.char = self.fp.read(1)
if self.char == "\n":
self.char = None
return s + "\n"
def _accept(prefix):
return prefix[:4] == "%!PS" or i32(prefix) == 0xC6D3D0C5L
##
# Image plugin for Encapsulated Postscript. This plugin supports only
# a few variants of this format.
class EpsImageFile(ImageFile.ImageFile):
"""EPS File Parser for the Python Imaging Library"""
format = "EPS"
format_description = "Encapsulated Postscript"
def _open(self):
# FIXME: should check the first 512 bytes to see if this
# really is necessary (platform-dependent, though...)
fp = PSFile(self.fp)
# HEAD
s = fp.read(512)
if s[:4] == "%!PS":
offset = 0
fp.seek(0, 2)
length = fp.tell()
elif i32(s) == 0xC6D3D0C5L:
offset = i32(s[4:])
length = i32(s[8:])
fp.seek(offset)
else:
raise SyntaxError, "not an EPS file"
fp.seek(offset)
box = None
self.mode = "RGB"
self.size = 1, 1 # FIXME: huh?
#
# Load EPS header
s = fp.readline()
while s:
if len(s) > 255:
raise SyntaxError, "not an EPS file"
if s[-2:] == '\r\n':
s = s[:-2]
elif s[-1:] == '\n':
s = s[:-1]
try:
m = split.match(s)
except re.error, v:
raise SyntaxError, "not an EPS file"
if m:
k, v = m.group(1, 2)
self.info[k] = v
if k == "BoundingBox":
try:
# Note: The DSC spec says that BoundingBox
# fields should be integers, but some drivers
# put floating point values there anyway.
box = map(int, map(float, string.split(v)))
self.size = box[2] - box[0], box[3] - box[1]
self.tile = [("eps", (0,0) + self.size, offset,
(length, box))]
except:
pass
else:
m = field.match(s)
if m:
k = m.group(1)
if k == "EndComments":
break
if k[:8] == "PS-Adobe":
self.info[k[:8]] = k[9:]
else:
self.info[k] = ""
else:
raise IOError, "bad EPS header"
s = fp.readline()
if s[:1] != "%":
break
#
# Scan for an "ImageData" descriptor
while s[0] == "%":
if len(s) > 255:
raise SyntaxError, "not an EPS file"
if s[-2:] == '\r\n':
s = s[:-2]
elif s[-1:] == '\n':
s = s[:-1]
if s[:11] == "%ImageData:":
[x, y, bi, mo, z3, z4, en, id] =\
string.split(s[11:], maxsplit=7)
x = int(x); y = int(y)
bi = int(bi)
mo = int(mo)
en = int(en)
if en == 1:
decoder = "eps_binary"
elif en == 2:
decoder = "eps_hex"
else:
break
if bi != 8:
break
if mo == 1:
self.mode = "L"
elif mo == 2:
self.mode = "LAB"
elif mo == 3:
self.mode = "RGB"
else:
break
if id[:1] == id[-1:] == '"':
id = id[1:-1]
# Scan forward to the actual image data
while 1:
s = fp.readline()
if not s:
break
if s[:len(id)] == id:
self.size = x, y
self.tile2 = [(decoder,
(0, 0, x, y),
fp.tell(),
0)]
return
s = fp.readline()
if not s:
break
if not box:
raise IOError, "cannot determine EPS bounding box"
def load(self):
# Load EPS via Ghostscript
if not self.tile:
return
self.im = Ghostscript(self.tile, self.size, self.fp)
self.mode = self.im.mode
self.size = self.im.size
self.tile = []
#
# --------------------------------------------------------------------
def _save(im, fp, filename, eps=1):
"""EPS Writer for the Python Imaging Library."""
#
# make sure image data is available
im.load()
#
# determine postscript image mode
if im.mode == "L":
operator = (8, 1, "image")
elif im.mode == "RGB":
operator = (8, 3, "false 3 colorimage")
elif im.mode == "CMYK":
operator = (8, 4, "false 4 colorimage")
else:
raise ValueError, "image mode is not supported"
if eps:
#
# write EPS header
fp.write("%!PS-Adobe-3.0 EPSF-3.0\n")
fp.write("%%Creator: PIL 0.1 EpsEncode\n")
#fp.write("%%CreationDate: %s"...)
fp.write("%%%%BoundingBox: 0 0 %d %d\n" % im.size)
fp.write("%%Pages: 1\n")
fp.write("%%EndComments\n")
fp.write("%%Page: 1 1\n")
fp.write("%%ImageData: %d %d " % im.size)
fp.write("%d %d 0 1 1 \"%s\"\n" % operator)
#
# image header
fp.write("gsave\n")
fp.write("10 dict begin\n")
fp.write("/buf %d string def\n" % (im.size[0] * operator[1]))
fp.write("%d %d scale\n" % im.size)
fp.write("%d %d 8\n" % im.size) # <= bits
fp.write("[%d 0 0 -%d 0 %d]\n" % (im.size[0], im.size[1], im.size[1]))
fp.write("{ currentfile buf readhexstring pop } bind\n")
fp.write("%s\n" % operator[2])
ImageFile._save(im, fp, [("eps", (0,0)+im.size, 0, None)])
fp.write("\n%%%%EndBinary\n")
fp.write("grestore end\n")
fp.flush()
#
# --------------------------------------------------------------------
Image.register_open(EpsImageFile.format, EpsImageFile, _accept)
Image.register_save(EpsImageFile.format, _save)
Image.register_extension(EpsImageFile.format, ".ps")
Image.register_extension(EpsImageFile.format, ".eps")
Image.register_mime(EpsImageFile.format, "application/postscript")
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