|
|
- #
- # 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).
- ##
-
- from . import Image, ImageFile, ImageSequence, PdfParser
- import io
- import os
- import time
-
- __version__ = "0.5"
-
-
- #
- # --------------------------------------------------------------------
-
- # object ids:
- # 1. catalogue
- # 2. pages
- # 3. image
- # 4. page
- # 5. page contents
-
-
- def _save_all(im, fp, filename):
- _save(im, fp, filename, save_all=True)
-
-
- ##
- # (Internal) Image save plugin for the PDF format.
-
- def _save(im, fp, filename, save_all=False):
- is_appending = im.encoderinfo.get("append", False)
- if is_appending:
- existing_pdf = PdfParser.PdfParser(f=fp, filename=filename, mode="r+b")
- else:
- existing_pdf = PdfParser.PdfParser(f=fp, filename=filename, mode="w+b")
-
- resolution = im.encoderinfo.get("resolution", 72.0)
-
- info = {
- "title": None if is_appending else os.path.splitext(
- os.path.basename(filename)
- )[0],
- "author": None,
- "subject": None,
- "keywords": None,
- "creator": None,
- "producer": None,
- "creationDate": None if is_appending else time.gmtime(),
- "modDate": None if is_appending else time.gmtime()
- }
- for k, default in info.items():
- v = im.encoderinfo.get(k) if k in im.encoderinfo else default
- if v:
- existing_pdf.info[k[0].upper() + k[1:]] = v
-
- #
- # make sure image data is available
- im.load()
-
- existing_pdf.start_writing()
- existing_pdf.write_header()
- existing_pdf.write_comment("created by PIL PDF driver " + __version__)
-
- #
- # pages
- ims = [im]
- if save_all:
- append_images = im.encoderinfo.get("append_images", [])
- for append_im in append_images:
- append_im.encoderinfo = im.encoderinfo.copy()
- ims.append(append_im)
- numberOfPages = 0
- image_refs = []
- page_refs = []
- contents_refs = []
- for im in ims:
- im_numberOfPages = 1
- if save_all:
- try:
- im_numberOfPages = im.n_frames
- except AttributeError:
- # Image format does not have n_frames.
- # It is a single frame image
- pass
- numberOfPages += im_numberOfPages
- for i in range(im_numberOfPages):
- image_refs.append(existing_pdf.next_object_id(0))
- page_refs.append(existing_pdf.next_object_id(0))
- contents_refs.append(existing_pdf.next_object_id(0))
- existing_pdf.pages.append(page_refs[-1])
-
- #
- # catalog and list of pages
- existing_pdf.write_catalog()
-
- pageNumber = 0
- for imSequence in ims:
- im_pages = ImageSequence.Iterator(imSequence) if save_all else [imSequence]
- for im in im_pages:
- # 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 = PdfParser.PdfName("DeviceGray")
- procset = "ImageB" # grayscale
- bits = 1
- elif im.mode == "L":
- filter = "DCTDecode"
- # params = "<< /Predictor 15 /Columns %d >>" % (width-2)
- colorspace = PdfParser.PdfName("DeviceGray")
- procset = "ImageB" # grayscale
- elif im.mode == "P":
- filter = "ASCIIHexDecode"
- palette = im.im.getpalette("RGB")
- colorspace = [
- PdfParser.PdfName("Indexed"),
- PdfParser.PdfName("DeviceRGB"),
- 255,
- PdfParser.PdfBinary(palette)
- ]
- procset = "ImageI" # indexed color
- elif im.mode == "RGB":
- filter = "DCTDecode"
- colorspace = PdfParser.PdfName("DeviceRGB")
- procset = "ImageC" # color images
- elif im.mode == "CMYK":
- filter = "DCTDecode"
- colorspace = PdfParser.PdfName("DeviceCMYK")
- procset = "ImageC" # color images
- else:
- raise ValueError("cannot save mode %s" % im.mode)
-
- #
- # image
-
- op = io.BytesIO()
-
- if filter == "ASCIIHexDecode":
- if bits == 1:
- # FIXME: the hex encoder doesn't support packed 1-bit
- # images; do things the hard way...
- data = im.tobytes("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":
- Image.SAVE["JPEG"](im, op, filename)
- 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)
-
- #
- # Get image characteristics
-
- width, height = im.size
-
- existing_pdf.write_obj(image_refs[pageNumber],
- stream=op.getvalue(),
- Type=PdfParser.PdfName("XObject"),
- Subtype=PdfParser.PdfName("Image"),
- Width=width, # * 72.0 / resolution,
- Height=height, # * 72.0 / resolution,
- Filter=PdfParser.PdfName(filter),
- BitsPerComponent=bits,
- DecodeParams=params,
- ColorSpace=colorspace)
-
- #
- # page
-
- existing_pdf.write_page(page_refs[pageNumber],
- Resources=PdfParser.PdfDict(
- ProcSet=[
- PdfParser.PdfName("PDF"),
- PdfParser.PdfName(procset)
- ],
- XObject=PdfParser.PdfDict(
- image=image_refs[pageNumber]
- )
- ),
- MediaBox=[
- 0,
- 0,
- int(width * 72.0 / resolution),
- int(height * 72.0 / resolution)
- ],
- Contents=contents_refs[pageNumber])
-
- #
- # page contents
-
- page_contents = PdfParser.make_bytes(
- "q %d 0 0 %d 0 0 cm /image Do Q\n" % (
- int(width * 72.0 / resolution),
- int(height * 72.0 / resolution)))
-
- existing_pdf.write_obj(contents_refs[pageNumber],
- stream=page_contents)
-
- pageNumber += 1
-
- #
- # trailer
- existing_pdf.write_xref_and_trailer()
- if hasattr(fp, "flush"):
- fp.flush()
- existing_pdf.close()
-
- #
- # --------------------------------------------------------------------
-
-
- Image.register_save("PDF", _save)
- Image.register_save_all("PDF", _save_all)
-
- Image.register_extension("PDF", ".pdf")
-
- Image.register_mime("PDF", "application/pdf")
|
