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- #
- # 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).
- ##
-
- import io
- import math
- import os
- import time
-
- from . import Image, ImageFile, ImageSequence, PdfParser, __version__, features
-
- #
- # --------------------------------------------------------------------
-
- # 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")
-
- dpi = im.encoderinfo.get("dpi")
- if dpi:
- x_resolution = dpi[0]
- y_resolution = dpi[1]
- else:
- x_resolution = y_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(f"created by Pillow {__version__} PDF driver")
-
- #
- # 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)
- number_of_pages = 0
- image_refs = []
- page_refs = []
- contents_refs = []
- for im in ims:
- im_number_of_pages = 1
- if save_all:
- try:
- im_number_of_pages = im.n_frames
- except AttributeError:
- # Image format does not have n_frames.
- # It is a single frame image
- pass
- number_of_pages += im_number_of_pages
- for i in range(im_number_of_pages):
- 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()
-
- page_number = 0
- for im_sequence in ims:
- im_pages = ImageSequence.Iterator(im_sequence) if save_all else [im_sequence]
- 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
- decode = None
-
- #
- # Get image characteristics
-
- width, height = im.size
-
- if im.mode == "1":
- if features.check("libtiff"):
- filter = "CCITTFaxDecode"
- bits = 1
- params = PdfParser.PdfArray(
- [
- PdfParser.PdfDict(
- {
- "K": -1,
- "BlackIs1": True,
- "Columns": width,
- "Rows": height,
- }
- )
- ]
- )
- else:
- filter = "DCTDecode"
- colorspace = PdfParser.PdfName("DeviceGray")
- procset = "ImageB" # grayscale
- elif im.mode == "L":
- filter = "DCTDecode"
- # params = f"<< /Predictor 15 /Columns {width-2} >>"
- colorspace = PdfParser.PdfName("DeviceGray")
- procset = "ImageB" # grayscale
- elif im.mode == "P":
- filter = "ASCIIHexDecode"
- palette = im.getpalette()
- 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 == "RGBA":
- filter = "JPXDecode"
- colorspace = PdfParser.PdfName("DeviceRGB")
- procset = "ImageC" # color images
- elif im.mode == "CMYK":
- filter = "DCTDecode"
- colorspace = PdfParser.PdfName("DeviceCMYK")
- procset = "ImageC" # color images
- decode = [1, 0, 1, 0, 1, 0, 1, 0]
- else:
- msg = f"cannot save mode {im.mode}"
- raise ValueError(msg)
-
- #
- # image
-
- op = io.BytesIO()
-
- if filter == "ASCIIHexDecode":
- ImageFile._save(im, op, [("hex", (0, 0) + im.size, 0, im.mode)])
- elif filter == "CCITTFaxDecode":
- im.save(
- op,
- "TIFF",
- compression="group4",
- # use a single strip
- strip_size=math.ceil(im.width / 8) * im.height,
- )
- elif filter == "DCTDecode":
- Image.SAVE["JPEG"](im, op, filename)
- elif filter == "JPXDecode":
- Image.SAVE["JPEG2000"](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:
- msg = f"unsupported PDF filter ({filter})"
- raise ValueError(msg)
-
- stream = op.getvalue()
- if filter == "CCITTFaxDecode":
- stream = stream[8:]
- filter = PdfParser.PdfArray([PdfParser.PdfName(filter)])
- else:
- filter = PdfParser.PdfName(filter)
-
- existing_pdf.write_obj(
- image_refs[page_number],
- stream=stream,
- Type=PdfParser.PdfName("XObject"),
- Subtype=PdfParser.PdfName("Image"),
- Width=width, # * 72.0 / x_resolution,
- Height=height, # * 72.0 / y_resolution,
- Filter=filter,
- BitsPerComponent=bits,
- Decode=decode,
- DecodeParms=params,
- ColorSpace=colorspace,
- )
-
- #
- # page
-
- existing_pdf.write_page(
- page_refs[page_number],
- Resources=PdfParser.PdfDict(
- ProcSet=[PdfParser.PdfName("PDF"), PdfParser.PdfName(procset)],
- XObject=PdfParser.PdfDict(image=image_refs[page_number]),
- ),
- MediaBox=[
- 0,
- 0,
- width * 72.0 / x_resolution,
- height * 72.0 / y_resolution,
- ],
- Contents=contents_refs[page_number],
- )
-
- #
- # page contents
-
- page_contents = b"q %f 0 0 %f 0 0 cm /image Do Q\n" % (
- width * 72.0 / x_resolution,
- height * 72.0 / y_resolution,
- )
-
- existing_pdf.write_obj(contents_refs[page_number], stream=page_contents)
-
- page_number += 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")
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