def _encode_image(cls, image_filename, lossless):
if lossless:
img = PnmPicture.read_file(image_filename)
if img.img_format == PnmPictureFormat.Bitmap:
# PDFs use exactly inverted syntax for 1-bit images
img.invert()
imgdata = EncodedObject.create(img.data)
(colorspace, bits_per_component) = {
PnmPictureFormat.Bitmap: (PDFImageColorSpace.DeviceGray, 1),
PnmPictureFormat.Graymap: (PDFImageColorSpace.DeviceGray, 8),
PnmPictureFormat.Pixmap: (PDFImageColorSpace.DeviceRGB, 8),
}[img.img_format]
width = img.width
height = img.height
else:
with open(image_filename, "rb") as f:
imgdata = EncodedObject(encoded_data=f.read(),
filtering=Filter.DCTDecode)
(width, height, colorspace,
bits_per_component) = cls._get_image_geometry(image_filename)
colorspace = {
"Gray": PDFImageColorSpace.DeviceGray,
"sRGB": PDFImageColorSpace.DeviceRGB,
}[colorspace]
return PDFImage(width=width,
height=height,
colorspace=colorspace,
bits_per_component=bits_per_component,
imgdata=imgdata,
inverted=False)
def _test_png_predictors(self, columns, encoded_data, pixel_data): obj = EncodedObject(encoded_data, Filter.Uncompressed, columns = columns, predictor = Predictor.PNGPredictionOptimum) obj_decode = obj.decode() self.assertEqual(len(obj_decode), len(pixel_data)) for line_offset in range(0, len(pixel_data), columns): self.assertEqual(obj_decode[line_offset : line_offset + columns], pixel_data[line_offset : line_offset + columns], "Row %d" % (line_offset // columns)) self.assertEqual(obj_decode, pixel_data)
def _generate_form(self):
font_xref = self._get_font_reference()
seal_template = PDFTemplate(
pkgutil.get_data("llpdf.resources", "seal.pdft"))
seal_xref = seal_template.merge_into_pdf(self._pdf)["SealObject"]
sign_template = PDFTemplate(
pkgutil.get_data("llpdf.resources", "sign_form.pdft"))
sign_template["FontXRef"] = font_xref
sign_template["SealFormXRef"] = seal_xref
signform_xref = sign_template.merge_into_pdf(
self._pdf)["SignFormObject"]
signform = self._pdf.lookup(signform_xref)
signform.content[PDFName("/BBox")] = self._get_signature_bbox()
signform_data = signform.stream.decode()
(posx, posy, width, height) = self._get_signature_bbox()
signform_vars = {
"WIDTH": b"%.0f" % (width - 1),
"HEIGHT": b"%.0f" % (height - 1),
"TEXT": self._get_signing_text(),
}
for (varname, replacement) in signform_vars.items():
key = ("${" + varname + "}").encode("ascii")
signform_data = signform_data.replace(key, replacement)
signform.set_stream(EncodedObject.create(signform_data, compress=True))
return signform_xref
def _add_xmp_metadata(self):
info_node_xref = self._pdf.trailer[PDFName("/Info")]
info_node = self._pdf.lookup(info_node_xref)
metadata_date = Timestamp.localnow()
modify_date = Timestamp.frompdf(info_node.content[PDFName("/ModDate")].decode("ascii")) if (PDFName("/ModDate") in info_node.content) else metadata_date
create_date = Timestamp.frompdf(info_node.content[PDFName("/CreationDate")].decode("ascii")) if (PDFName("/CreationDate") in info_node.content) else metadata_date
xmp_metadata = {
"creator_tool": self._pdf.get_info("Creator"),
"producer": self._pdf.get_info("Producer"),
"modify_date": modify_date.format_xml(),
"create_date": create_date.format_xml(),
"metadata_date": metadata_date.format_xml(),
"description": self._pdf.get_info("Subject"),
"title": self._pdf.get_info("Title"),
"creator": self._pdf.get_info("Author"),
"keywords": self._pdf.get_info("Keywords"),
"document_uuid": str(uuid.uuid4()),
"instance_uuid": str(uuid.uuid4()),
"llpdf_version": "llpdf " + llpdf.VERSION,
}
xmp_metadata_template = pkgutil.get_data("llpdf.resources", "xmp_metadata.xml").decode("utf-8")
stream = (xmp_metadata_template % xmp_metadata).encode("utf-8")
content = {
PDFName("/Type"): PDFName("/Metadata"),
PDFName("/Subtype"): PDFName("/XML"),
}
objid = self._pdf.get_free_objid()
pdf_object = PDFObject.create(objid, gennum = 0, content = content, stream = EncodedObject.create(stream, compress = False))
self._pdf.replace_object(pdf_object)
return pdf_object.xref
def _create_object(self, content, raw_stream=None):
objid = self._pdf.get_free_objid()
obj = PDFObject.create(objid=objid, gennum=0, content=content)
if raw_stream is not None:
obj.set_stream(EncodedObject.create(raw_stream))
self._pdf.replace_object(obj)
return PDFXRef(objid, 0)
def get_fontfile_object(self, objid):
content = {
PDFName("/Length1"): len(self._cleardata),
PDFName("/Length2"): len(self._cipherdata),
PDFName("/Length3"): len(self._trailerdata),
}
stream = EncodedObject.create(self._cleardata + self._cipherdata + self._trailerdata, compress = True)
obj = PDFObject.create(objid, 0, content, stream)
return obj
def serialize_xref_object(self, trailer_dict, objid):
offset_width = self._get_offset_width()
content = dict(trailer_dict)
content.update({
PDFName("/Type"): PDFName("/XRef"),
PDFName("/Index"): [ 0, self._max_objid + 1 ],
PDFName("/Size"): self._max_objid + 1,
PDFName("/W"): [ 1, offset_width, 1 ],
})
data = self._serialize_xref_data(offset_width)
return PDFObject.create(objid = objid, gennum = 0, content = content, stream = EncodedObject.create(data))
def _add_color_profile(self):
if self._args.color_profile is None:
profile_data = pkgutil.get_data("llpdf.resources", "sRGB_IEC61966-2-1_black_scaled.icc")
else:
with open(self._args.color_profile, "rb") as f:
profile_data = f.read()
content = {
PDFName("/N"): 3,
PDFName("/Range"): [ 0, 1, 0, 1, 0, 1 ],
}
objid = self._pdf.get_free_objid()
pdf_object = PDFObject.create(objid, gennum = 0, content = content, stream = EncodedObject.create(profile_data))
self._pdf.replace_object(pdf_object)
return pdf_object.xref
def run(self):
with open(self._args.embed_payload, "rb") as f:
payload = f.read()
objid = self._pdf.get_free_objid()
self._log.debug(
"Embedding %d bytes payload from file \"%s\" into PDF file as objid %d",
len(payload), self._args.embed_payload, objid)
mtime = os.stat(self._args.embed_payload).st_mtime
mtime_str = datetime.datetime.utcfromtimestamp(mtime).strftime(
"%Y-%m-%dT%H:%M:%SZ")
content = {
PDFName("/PDFMinify.OriginalFilename"):
os.path.basename(self._args.embed_payload).encode(),
PDFName("/PDFMinify.MTime"):
mtime_str.encode(),
PDFName("/PDFMinify.Version"):
llpdf.VERSION.encode(),
}
obj = PDFObject.create(objid=objid, gennum=0, content=content)
obj.set_stream(EncodedObject.create(payload, compress=False))
self._pdf.replace_object(obj)
def stream(self):
if not self.has_stream:
return None
else:
return EncodedObject.from_object(self)
def test_flate_decompress(self):
compressed_data = bytes.fromhex(
"78 9c 73 cb cf 4f 4a 2c 02 00 07 eb 02 5a")
obj = EncodedObject(compressed_data, Filter.FlateDecode)
self.assertEqual(obj.decode(), b"Foobar")
def test_no_decompress(self):
uncompressed_data = b"Foobar"
obj = EncodedObject(uncompressed_data, Filter.Uncompressed)
self.assertEqual(obj.decode(), b"Foobar")
def append_stream(self, text):
new_data = text.encode("utf-8")
if self.contents_obj.stream is not None:
prev_data = self.contents_obj.stream.decode()
new_data = prev_data + b"\n" + new_data
self.contents_obj.set_stream(EncodedObject.create(new_data))
def serialize(self, serializer):
header = [ ]
data = bytearray()
for obj in self._contained_objects:
obj_data = serializer.serialize(obj.content)
offset = len(data)
header.append(obj.objid)
header.append(offset)
data += obj_data + b"\n"
header = " ".join(str(value) for value in header)
header = header.encode("utf-8") + b"\n"
full_data = header + data
content = {
PDFName("/Type"): PDFName("/ObjStm"),
PDFName("/N"): self.objects_inside_count,
PDFName("/First"): len(header),
}
return PDFObject.create(objid = self.objid, gennum = 0, content = content, stream = EncodedObject.create(full_data))
def run(self):
for obj in self._pdf.stream_objects:
if obj.stream.compressed and obj.stream.decompressible:
uncompressed_stream = EncodedObject.create(obj.stream.decode(),
compress=False)
obj.set_stream(uncompressed_stream)
def run(self):
# Put an ID into the PDF
self._pdf.trailer[PDFName("/ID")] = [os.urandom(16), os.urandom(16)]
# Do not interpolate any image objects
for image_obj in self._pdf.image_objects:
image_obj.content[PDFName("/Interpolate")] = False
# No pages may be transparency groups
for page in self._pdf.pages:
if PDFName("/Group") in page.content:
del page.content[PDFName("/Group")]
# No transparency groups in Form XObjects
for obj in self._pdf:
if (obj.getattr(PDFName("/Type"))
== PDFName("/XObject")) and (obj.getattr(
PDFName("/Subtype")) == PDFName("/Form")) and (
obj.getattr(PDFName("/Group")) is not None):
del obj.content[PDFName("/Group")]
# Add color profile data
color_profile_xref = self._add_color_profile()
# Add color intent object
color_intent_xref = self._add_color_intent(color_profile_xref)
# Add XMP metadata
metadata_xref = self._add_xmp_metadata()
# Set output intent and metadata reference for all catalogs
for obj in self._pdf:
if obj.getattr(PDFName("/Type")) == PDFName("/Catalog"):
obj.content[PDFName("/OutputIntents")] = color_intent_xref
obj.content[PDFName("/Metadata")] = metadata_xref
# Set all annotations with annotation flag "printable" (4)
for obj in self._pdf:
if obj.getattr(PDFName("/Type")) == PDFName("/Annot"):
obj.content[PDFName("/F")] = 4
fixed_descriptors = set()
for obj in list(self._pdf):
if obj.getattr(PDFName("/Type")) == PDFName("/Font"):
font_obj = obj
if font_obj.getattr(
PDFName("/Subtype")) == PDFName("/CIDFontType2"):
# Type2 fonts need to have a CIDtoGIDMap
font_obj.content[PDFName("/CIDToGIDMap")] = PDFName(
"/Identity")
if PDFName("/FontDescriptor") in font_obj.content:
font_descriptor_xref = font_obj.content[PDFName(
"/FontDescriptor")]
if font_descriptor_xref in fixed_descriptors:
continue
fixed_descriptors.add(font_descriptor_xref)
font_descriptor_obj = self._pdf.lookup(
font_descriptor_xref)
if font_obj.getattr(
PDFName("/Subtype")) == PDFName("/Type1"):
# Update Type1 font descriptors with missing CharSet entries
font_file_obj = self._pdf.lookup(
font_descriptor_obj.content[PDFName("/FontFile")])
t1_font = T1Font.from_fontfile_obj(font_file_obj)
font_descriptor_obj.content[PDFName(
"/CharSet")] = t1_font.charset_string
elif font_obj.getattr(
PDFName("/Subtype")) == PDFName("/CIDFontType2"):
# Type2 font descriptors need to have a CIDSet
glyph_count = self.type2_font_glyph_count(
font_obj.content[PDFName("/W")])
full_bytes = glyph_count // 8
set_bits = glyph_count % 8
last_byte = ((1 << set_bits) - 1) << (8 - set_bits)
self._log.debug(
"Assuming CIDSet for %d glyphs of %d full 0xff bytes and a final value of 0x%x.",
glyph_count, full_bytes, last_byte)
cidset_objid = self._pdf.get_free_objid()
stream = (bytes([0xff]) * full_bytes) + bytes(
[last_byte])
pdf_object = PDFObject.create(
cidset_objid,
gennum=0,
content={},
stream=EncodedObject.create(stream))
self._pdf.replace_object(pdf_object)
font_descriptor_obj.content[PDFName(
"/CIDSet")] = pdf_object.xref
def put_image(self, pdfimage):
if pdfimage.image_format not in [ "JPEG", "RGB", "GRAY" ]:
raise UnsupportedError("PDF can only handle JPEG, RGB or GRAY image formats, but %s was supplied." % (pdfimage.image_format))
custom_metadata = {
"resolution_dpi": list(pdfimage.resolution_dpi),
"comment": pdfimage.comment,
}
image = self.pdf.new_object({
PDFName("/Type"): PDFName("/XObject"),
PDFName("/Subtype"): PDFName("/Image"),
PDFName("/Interpolate"): True,
PDFName("/Width"): pdfimage.dimensions.width,
PDFName("/Height"): pdfimage.dimensions.height,
PDFName("/CustomMetadata"): PDFString(json.dumps(custom_metadata)),
})
if pdfimage.image_format == "JPEG":
image.set_stream(EncodedObject(encoded_data = pdfimage.data, filtering = Filter.DCTDecode))
elif pdfimage.image_format in [ "RGB", "GRAY" ]:
image.set_stream(EncodedObject.create(pdfimage.data, compress = True))
else:
raise NotImplementedError(pdfimage.image_format)
if pdfimage.pixel_format == PixelFormat.RGB:
image.content[PDFName("/ColorSpace")] = PDFName("/DeviceRGB")
image.content[PDFName("/BitsPerComponent")] = 8
elif pdfimage.pixel_format == PixelFormat.Grayscale:
image.content[PDFName("/ColorSpace")] = PDFName("/DeviceGray")
image.content[PDFName("/BitsPerComponent")] = 8
elif pdfimage.pixel_format == PixelFormat.BlackWhite:
image.content[PDFName("/ColorSpace")] = PDFName("/DeviceGray")
image.content[PDFName("/BitsPerComponent")] = 1
else:
raise NotImplementedError(pdfimage.pixel_format)
image_extents_mm = pdfimage.extents_mm
image_scale_x = self.printable_area_mm.width / image_extents_mm.width
image_scale_y = self.printable_area_mm.height / image_extents_mm.height
image_scalar = min(image_scale_x, image_scale_y)
if image_scalar > 1:
# Never enlarge
image_scalar = 1
printed_size_mm = image_extents_mm * image_scalar
page_dimensions_mm = self._hl_page.extents_mm
offset_mm = (page_dimensions_mm - printed_size_mm) / 2
offset_dots = offset_mm * 72 / 25.4
printed_size_dots = printed_size_mm * 72 / 25.4
params = {
"xoffset": offset_dots.width,
"yoffset": offset_dots.height,
"xscalar": printed_size_dots.width,
"yscalar": printed_size_dots.height,
}
self._hl_page.append_stream(textwrap.dedent("""\
%(xscalar)f 0 0 %(yscalar)f %(xoffset)f %(yoffset)f cm
/Img Do
""" % (params)))
page_obj = self._hl_page.page_obj
if not PDFName("/Resources") in page_obj.content:
page_obj.content[PDFName("/Resources")] = { }
if not PDFName("/XObject") in page_obj.content[PDFName("/Resources")]:
page_obj.content[PDFName("/Resources")][PDFName("/XObject")] = { }
page_obj.content[PDFName("/Resources")][PDFName("/XObject")][PDFName("/Img")] = image.xref
