#
# The Python Imaging Library.
# $Id$
#
# PDF (Acrobat) file handling
#
# History:
# 1996-07-16 fl Created
# 1997-01-18 fl Fixed header
# 2004-02-21 fl Fixes for 1/L/CMYK images, etc.
# 2004-02-24 fl Fixes for 1 and P images.
#
# Copyright (c) 1997-2004 by Secret Labs AB. All rights reserved.
# Copyright (c) 1996-1997 by Fredrik Lundh.
#
# See the README file for information on usage and redistribution.
#
##
# Image plugin for PDF images (output only).
##
__version__ = "0.4"
import Image, ImageFile
import StringIO
#
# --------------------------------------------------------------------
# object ids:
# 1. catalogue
# 2. pages
# 3. image
# 4. page
# 5. page contents
def _obj(fp, obj, **dict):
fp.write("%d 0 obj\n" % obj)
if dict:
fp.write("<<\n")
for k, v in dict.items():
if v is not None:
fp.write("/%s %s\n" % (k, v))
fp.write(">>\n")
def _endobj(fp):
fp.write("endobj\n")
##
# (Internal) Image save plugin for the PDF format.
def _save(im, fp, filename):
resolution = im.encoderinfo.get("resolution", 72.0)
#
# make sure image data is available
im.load()
xref = [0]*(5+1) # placeholders
fp.write("%PDF-1.2\n")
fp.write("% created by PIL PDF driver " + __version__ + "\n")
#
# Get image characteristics
width, height = im.size
# FIXME: Should replace ASCIIHexDecode with RunLengthDecode (packbits)
# or LZWDecode (tiff/lzw compression). Note that PDF 1.2 also supports
# Flatedecode (zip compression).
bits = 8
params = None
if im.mode == "1":
filter = "/ASCIIHexDecode"
colorspace = "/DeviceGray"
procset = "/ImageB" # grayscale
bits = 1
elif im.mode == "L":
filter = "/DCTDecode"
# params = "<< /Predictor 15 /Columns %d >>" % (width-2)
colorspace = "/DeviceGray"
procset = "/ImageB" # grayscale
elif im.mode == "P":
filter = "/ASCIIHexDecode"
colorspace = "[ /Indexed /DeviceRGB 255 <"
palette = im.im.getpalette("RGB")
for i in range(256):
r = ord(palette[i*3])
g = ord(palette[i*3+1])
b = ord(palette[i*3+2])
colorspace = colorspace + "%02x%02x%02x " % (r, g, b)
colorspace = colorspace + "> ]"
procset = "/ImageI" # indexed color
elif im.mode == "RGB":
filter = "/DCTDecode"
colorspace = "/DeviceRGB"
procset = "/ImageC" # color images
elif im.mode == "CMYK":
filter = "/DCTDecode"
colorspace = "/DeviceCMYK"
procset = "/ImageC" # color images
else:
raise ValueError("cannot save mode %s" % im.mode)
#
# catalogue
xref[1] = fp.tell()
_obj(fp, 1, Type = "/Catalog",
Pages = "2 0 R")
_endobj(fp)
#
# pages
xref[2] = fp.tell()
_obj(fp, 2, Type = "/Pages",
Count = 1,
Kids = "[4 0 R]")
_endobj(fp)
#
# image
op = StringIO.StringIO()
if filter == "/ASCIIHexDecode":
if bits == 1:
# FIXME: the hex encoder doesn't support packed 1-bit
# images; do things the hard way...
data = im.tostring("raw", "1")
im = Image.new("L", (len(data), 1), None)
im.putdata(data)
ImageFile._save(im, op, [("hex", (0,0)+im.size, 0, im.mode)])
elif filter == "/DCTDecode":
ImageFile._save(im, op, [("jpeg", (0,0)+im.size, 0, im.mode)])
elif filter == "/FlateDecode":
ImageFile._save(im, op, [("zip", (0,0)+im.size, 0, im.mode)])
elif filter == "/RunLengthDecode":
ImageFile._save(im, op, [("packbits", (0,0)+im.size, 0, im.mode)])
else:
raise ValueError("unsupported PDF filter (%s)" % filter)
xref[3] = fp.tell()
_obj(fp, 3, Type = "/XObject",
Subtype = "/Image",
Width = width, # * 72.0 / resolution,
Height = height, # * 72.0 / resolution,
Length = len(op.getvalue()),
Filter = filter,
BitsPerComponent = bits,
DecodeParams = params,
ColorSpace = colorspace)
fp.write("stream\n")
fp.write(op.getvalue())
fp.write("\nendstream\n")
_endobj(fp)
#
# page
xref[4] = fp.tell()
_obj(fp, 4)
fp.write("<<\n/Type /Page\n/Parent 2 0 R\n"\
"/Resources <<\n/ProcSet [ /PDF %s ]\n"\
"/XObject << /image 3 0 R >>\n>>\n"\
"/MediaBox [ 0 0 %d %d ]\n/Contents 5 0 R\n>>\n" %\
(procset, int(width * 72.0 /resolution) , int(height * 72.0 / resolution)))
_endobj(fp)
#
# page contents
op = StringIO.StringIO()
op.write("q %d 0 0 %d 0 0 cm /image Do Q\n" % (int(width * 72.0 / resolution), int(height * 72.0 / resolution)))
xref[5] = fp.tell()
_obj(fp, 5, Length = len(op.getvalue()))
fp.write("stream\n")
fp.write(op.getvalue())
fp.write("\nendstream\n")
_endobj(fp)
#
# trailer
startxref = fp.tell()
fp.write("xref\n0 %d\n0000000000 65535 f \n" % len(xref))
for x in xref[1:]:
fp.write("%010d 00000 n \n" % x)
fp.write("trailer\n<<\n/Size %d\n/Root 1 0 R\n>>\n" % len(xref))
fp.write("startxref\n%d\n%%%%EOF\n" % startxref)
fp.flush()
#
# --------------------------------------------------------------------
Image.register_save("PDF", _save)
Image.register_extension("PDF", ".pdf")
Image.register_mime("PDF", "application/pdf")
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