#
|
# 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")
|
