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- #
- # The Python Imaging Library.
- # $Id: PdfImagePlugin.py 2438 2005-05-25 21:09:48Z Fredrik $
- #
- # 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):
-
- #
- # 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,
- Height = height,
- 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, width, height))
- _endobj(fp)
-
- #
- # page contents
-
- op = StringIO.StringIO()
-
- op.write("q %d 0 0 %d 0 0 cm /image Do Q\n" % (width, height))
-
- 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")
-