Pillow/src/PIL/PdfImagePlugin.py
Jon Dufresne d50445ff30 Introduce isort to automate import ordering and formatting
Similar to the recent adoption of Black. isort is a Python utility to
sort imports alphabetically and automatically separate into sections. By
using isort, contributors can quickly and automatically conform to the
projects style without thinking. Just let the tool do it.

Uses the configuration recommended by the Black to avoid conflicts of
style.

Rewrite TestImageQt.test_deprecated to no rely on import order.
2019-07-06 16:11:35 -07:00

249 lines
7.5 KiB
Python

#
# 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 os
import time
from . import Image, ImageFile, ImageSequence, PdfParser
# __version__ is deprecated and will be removed in a future version. Use
# PIL.__version__ instead.
__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", im.size)
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")