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diff --git a/PdfFileTransformer/PyPDF2/generic.py b/PdfFileTransformer/PyPDF2/generic.py
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+# vim: sw=4:expandtab:foldmethod=marker
+#
+# Copyright (c) 2006, Mathieu Fenniak
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+# * Redistributions of source code must retain the above copyright notice,
+# this list of conditions and the following disclaimer.
+# * Redistributions in binary form must reproduce the above copyright notice,
+# this list of conditions and the following disclaimer in the documentation
+# and/or other materials provided with the distribution.
+# * The name of the author may not be used to endorse or promote products
+# derived from this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+
+"""
+Implementation of generic PDF objects (dictionary, number, string, and so on)
+"""
+__author__ = "Mathieu Fenniak"
+__author_email__ = "biziqe@mathieu.fenniak.net"
+
+import re
+from .utils import readNonWhitespace, RC4_encrypt, skipOverComment
+from .utils import b_, u_, chr_, ord_
+from .utils import PdfStreamError
+import warnings
+from . import filters
+from . import utils
+import decimal
+import codecs
+import sys
+#import debugging
+
+ObjectPrefix = b_('/<[tf(n%')
+NumberSigns = b_('+-')
+IndirectPattern = re.compile(b_(r"[+-]?(\d+)\s+(\d+)\s+R[^a-zA-Z]"))
+
+
+def readObject(stream, pdf):
+    tok = stream.read(1)
+    stream.seek(-1, 1) # reset to start
+    idx = ObjectPrefix.find(tok)
+    if idx == 0:
+        # name object
+        return NameObject.readFromStream(stream, pdf)
+    elif idx == 1:
+        # hexadecimal string OR dictionary
+        peek = stream.read(2)
+        stream.seek(-2, 1) # reset to start
+        if peek == b_('<<'):
+            return DictionaryObject.readFromStream(stream, pdf)
+        else:
+            return readHexStringFromStream(stream)
+    elif idx == 2:
+        # array object
+        return ArrayObject.readFromStream(stream, pdf)
+    elif idx == 3 or idx == 4:
+        # boolean object
+        return BooleanObject.readFromStream(stream)
+    elif idx == 5:
+        # string object
+        return readStringFromStream(stream)
+    elif idx == 6:
+        # null object
+        return NullObject.readFromStream(stream)
+    elif idx == 7:
+        # comment
+        while tok not in (b_('\r'), b_('\n')):
+            tok = stream.read(1)
+            # Prevents an infinite loop by raising an error if the stream is at
+            # the EOF
+            if len(tok) <= 0:
+                raise PdfStreamError("File ended unexpectedly.")
+        tok = readNonWhitespace(stream)
+        stream.seek(-1, 1)
+        return readObject(stream, pdf)
+    else:
+        # number object OR indirect reference
+        peek = stream.read(20)
+        stream.seek(-len(peek), 1) # reset to start
+        if IndirectPattern.match(peek) != None:
+            return IndirectObject.readFromStream(stream, pdf)
+        else:
+            return NumberObject.readFromStream(stream)
+
+
+class PdfObject(object):
+    def getObject(self):
+        """Resolves indirect references."""
+        return self
+
+
+class NullObject(PdfObject):
+    def writeToStream(self, stream, encryption_key):
+        stream.write(b_("null"))
+
+    def readFromStream(stream):
+        nulltxt = stream.read(4)
+        if nulltxt != b_("null"):
+            raise utils.PdfReadError("Could not read Null object")
+        return NullObject()
+    readFromStream = staticmethod(readFromStream)
+
+
+class BooleanObject(PdfObject):
+    def __init__(self, value):
+        self.value = value
+
+    def writeToStream(self, stream, encryption_key):
+        if self.value:
+            stream.write(b_("true"))
+        else:
+            stream.write(b_("false"))
+
+    def readFromStream(stream):
+        word = stream.read(4)
+        if word == b_("true"):
+            return BooleanObject(True)
+        elif word == b_("fals"):
+            stream.read(1)
+            return BooleanObject(False)
+        else:
+            raise utils.PdfReadError('Could not read Boolean object')
+    readFromStream = staticmethod(readFromStream)
+
+
+class ArrayObject(list, PdfObject):
+    def writeToStream(self, stream, encryption_key):
+        stream.write(b_("["))
+        for data in self:
+            stream.write(b_(" "))
+            data.writeToStream(stream, encryption_key)
+        stream.write(b_(" ]"))
+
+    def readFromStream(stream, pdf):
+        arr = ArrayObject()
+        tmp = stream.read(1)
+        if tmp != b_("["):
+            raise utils.PdfReadError("Could not read array")
+        while True:
+            # skip leading whitespace
+            tok = stream.read(1)
+            while tok.isspace():
+                tok = stream.read(1)
+            stream.seek(-1, 1)
+            # check for array ending
+            peekahead = stream.read(1)
+            if peekahead == b_("]"):
+                break
+            stream.seek(-1, 1)
+            # read and append obj
+            arr.append(readObject(stream, pdf))
+        return arr
+    readFromStream = staticmethod(readFromStream)
+
+
+class IndirectObject(PdfObject):
+    def __init__(self, idnum, generation, pdf):
+        self.idnum = idnum
+        self.generation = generation
+        self.pdf = pdf
+
+    def getObject(self):
+        return self.pdf.getObject(self).getObject()
+
+    def __repr__(self):
+        return "IndirectObject(%r, %r)" % (self.idnum, self.generation)
+
+    def __eq__(self, other):
+        return (
+            other != None and
+            isinstance(other, IndirectObject) and
+            self.idnum == other.idnum and
+            self.generation == other.generation and
+            self.pdf is other.pdf
+            )
+
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
+    def writeToStream(self, stream, encryption_key):
+        stream.write(b_("%s %s R" % (self.idnum, self.generation)))
+
+    def readFromStream(stream, pdf):
+        idnum = b_("")
+        while True:
+            tok = stream.read(1)
+            if not tok:
+                # stream has truncated prematurely
+                raise PdfStreamError("Stream has ended unexpectedly")
+            if tok.isspace():
+                break
+            idnum += tok
+        generation = b_("")
+        while True:
+            tok = stream.read(1)
+            if not tok:
+                # stream has truncated prematurely
+                raise PdfStreamError("Stream has ended unexpectedly")
+            if tok.isspace():
+                if not generation:
+                    continue
+                break
+            generation += tok
+        r = readNonWhitespace(stream)
+        if r != b_("R"):
+            raise utils.PdfReadError("Error reading indirect object reference at byte %s" % utils.hexStr(stream.tell()))
+        return IndirectObject(int(idnum), int(generation), pdf)
+    readFromStream = staticmethod(readFromStream)
+
+
+class FloatObject(decimal.Decimal, PdfObject):
+    def __new__(cls, value="0", context=None):
+        try:
+            return decimal.Decimal.__new__(cls, utils.str_(value), context)
+        except:
+            return decimal.Decimal.__new__(cls, str(value))
+
+    def __repr__(self):
+        if self == self.to_integral():
+            return str(self.quantize(decimal.Decimal(1)))
+        else:
+            # Standard formatting adds useless extraneous zeros.
+            o = "%.5f" % self
+            # Remove the zeros.
+            while o and o[-1] == '0':
+                o = o[:-1]
+            return o
+
+    def as_numeric(self):
+        return float(b_(repr(self)))
+
+    def writeToStream(self, stream, encryption_key):
+        stream.write(b_(repr(self)))
+
+
+class NumberObject(int, PdfObject):
+    NumberPattern = re.compile(b_('[^+-.0-9]'))
+    ByteDot = b_(".")
+
+    def __new__(cls, value):
+        val = int(value)
+        try:
+            return int.__new__(cls, val)
+        except OverflowError:
+            return int.__new__(cls, 0)
+
+    def as_numeric(self):
+        return int(b_(repr(self)))
+
+    def writeToStream(self, stream, encryption_key):
+        stream.write(b_(repr(self)))
+
+    def readFromStream(stream):
+        num = utils.readUntilRegex(stream, NumberObject.NumberPattern)
+        if num.find(NumberObject.ByteDot) != -1:
+            return FloatObject(num)
+        else:
+            return NumberObject(num)
+    readFromStream = staticmethod(readFromStream)
+
+
+##
+# Given a string (either a "str" or "unicode"), create a ByteStringObject or a
+# TextStringObject to represent the string.
+def createStringObject(string):
+    if isinstance(string, utils.string_type):
+        return TextStringObject(string)
+    elif isinstance(string, utils.bytes_type):
+        try:
+            if string.startswith(codecs.BOM_UTF16_BE):
+                retval = TextStringObject(string.decode("utf-16"))
+                retval.autodetect_utf16 = True
+                return retval
+            else:
+                # This is probably a big performance hit here, but we need to
+                # convert string objects into the text/unicode-aware version if
+                # possible... and the only way to check if that's possible is
+                # to try.  Some strings are strings, some are just byte arrays.
+                retval = TextStringObject(decode_pdfdocencoding(string))
+                retval.autodetect_pdfdocencoding = True
+                return retval
+        except UnicodeDecodeError:
+            return ByteStringObject(string)
+    else:
+        raise TypeError("createStringObject should have str or unicode arg")
+
+
+def readHexStringFromStream(stream):
+    stream.read(1)
+    txt = ""
+    x = b_("")
+    while True:
+        tok = readNonWhitespace(stream)
+        if not tok:
+            # stream has truncated prematurely
+            raise PdfStreamError("Stream has ended unexpectedly")
+        if tok == b_(">"):
+            break
+        x += tok
+        if len(x) == 2:
+            txt += chr(int(x, base=16))
+            x = b_("")
+    if len(x) == 1:
+        x += b_("0")
+    if len(x) == 2:
+        txt += chr(int(x, base=16))
+    return createStringObject(b_(txt))
+
+
+def readStringFromStream(stream):
+    tok = stream.read(1)
+    parens = 1
+    txt = b_("")
+    while True:
+        tok = stream.read(1)
+        if not tok:
+            # stream has truncated prematurely
+            raise PdfStreamError("Stream has ended unexpectedly")
+        if tok == b_("("):
+            parens += 1
+        elif tok == b_(")"):
+            parens -= 1
+            if parens == 0:
+                break
+        elif tok == b_("\\"):
+            tok = stream.read(1)
+            ESCAPE_DICT = {b_("n") : b_("\n"),
+                           b_("r") : b_("\r"),
+                           b_("t") : b_("\t"),
+                           b_("b") : b_("\b"),
+                           b_("f") : b_("\f"),
+                           b_("c") : b_("\c"),
+                           b_("(") : b_("("),
+                           b_(")") : b_(")"),
+                           b_("/") : b_("/"),
+                           b_("\\") : b_("\\"),
+                           b_(" ") : b_(" "),
+                           b_("/") : b_("/"),
+                           b_("%") : b_("%"),
+                           b_("<") : b_("<"),
+                           b_(">") : b_(">"),
+                           b_("[") : b_("["), 
+                           b_("]") : b_("]"),
+                           b_("#") : b_("#"),
+                           b_("_") : b_("_"),
+                           b_("&") : b_("&"),
+                           b_('$') : b_('$'),
+                           }
+            try:
+                tok = ESCAPE_DICT[tok]
+            except KeyError:
+                if tok.isdigit():
+                    # "The number ddd may consist of one, two, or three
+                    # octal digits; high-order overflow shall be ignored.
+                    # Three octal digits shall be used, with leading zeros
+                    # as needed, if the next character of the string is also
+                    # a digit." (PDF reference 7.3.4.2, p 16)
+                    for i in range(2):
+                        ntok = stream.read(1)
+                        if ntok.isdigit():
+                            tok += ntok
+                        else:
+                            break
+                    tok = b_(chr(int(tok, base=8)))
+                elif tok in b_("\n\r"):
+                    # This case is  hit when a backslash followed by a line
+                    # break occurs.  If it's a multi-char EOL, consume the
+                    # second character:
+                    tok = stream.read(1)
+                    if not tok in b_("\n\r"):
+                        stream.seek(-1, 1)
+                    # Then don't add anything to the actual string, since this
+                    # line break was escaped:
+                    tok = b_('')
+                else:
+                    raise utils.PdfReadError(r"Unexpected escaped string: %s" % tok)
+        txt += tok
+    return createStringObject(txt)
+
+
+##
+# Represents a string object where the text encoding could not be determined.
+# This occurs quite often, as the PDF spec doesn't provide an alternate way to
+# represent strings -- for example, the encryption data stored in files (like
+# /O) is clearly not text, but is still stored in a "String" object.
+class ByteStringObject(utils.bytes_type, PdfObject):
+
+    ##
+    # For compatibility with TextStringObject.original_bytes.  This method
+    # returns self.
+    original_bytes = property(lambda self: self)
+
+    def writeToStream(self, stream, encryption_key):
+        bytearr = self
+        if encryption_key:
+            bytearr = RC4_encrypt(encryption_key, bytearr)
+        stream.write(b_("<"))
+        stream.write(utils.hexencode(bytearr))
+        stream.write(b_(">"))
+
+
+##
+# Represents a string object that has been decoded into a real unicode string.
+# If read from a PDF document, this string appeared to match the
+# PDFDocEncoding, or contained a UTF-16BE BOM mark to cause UTF-16 decoding to
+# occur.
+class TextStringObject(utils.string_type, PdfObject):
+    autodetect_pdfdocencoding = False
+    autodetect_utf16 = False
+
+    ##
+    # It is occasionally possible that a text string object gets created where
+    # a byte string object was expected due to the autodetection mechanism --
+    # if that occurs, this "original_bytes" property can be used to
+    # back-calculate what the original encoded bytes were.
+    original_bytes = property(lambda self: self.get_original_bytes())
+
+    def get_original_bytes(self):
+        # We're a text string object, but the library is trying to get our raw
+        # bytes.  This can happen if we auto-detected this string as text, but
+        # we were wrong.  It's pretty common.  Return the original bytes that
+        # would have been used to create this object, based upon the autodetect
+        # method.
+        if self.autodetect_utf16:
+            return codecs.BOM_UTF16_BE + self.encode("utf-16be")
+        elif self.autodetect_pdfdocencoding:
+            return encode_pdfdocencoding(self)
+        else:
+            raise Exception("no information about original bytes")
+
+    def writeToStream(self, stream, encryption_key):
+        # Try to write the string out as a PDFDocEncoding encoded string.  It's
+        # nicer to look at in the PDF file.  Sadly, we take a performance hit
+        # here for trying...
+        try:
+            bytearr = encode_pdfdocencoding(self)
+        except UnicodeEncodeError:
+            bytearr = codecs.BOM_UTF16_BE + self.encode("utf-16be")
+        if encryption_key:
+            bytearr = RC4_encrypt(encryption_key, bytearr)
+            obj = ByteStringObject(bytearr)
+            obj.writeToStream(stream, None)
+        else:
+            stream.write(b_("("))
+            for c in bytearr:
+                if not chr_(c).isalnum() and c != b_(' '):
+                    stream.write(b_("\\%03o" % ord_(c)))
+                else:
+                    stream.write(b_(chr_(c)))
+            stream.write(b_(")"))
+
+
+class NameObject(str, PdfObject):
+    delimiterPattern = re.compile(b_(r"\s+|[\(\)<>\[\]{}/%]"))
+    surfix = b_("/")
+
+    def writeToStream(self, stream, encryption_key):
+        stream.write(b_(self))
+
+    def readFromStream(stream, pdf):
+        debug = False
+        if debug: print((stream.tell()))
+        name = stream.read(1)
+        if name != NameObject.surfix:
+            raise utils.PdfReadError("name read error")
+        name += utils.readUntilRegex(stream, NameObject.delimiterPattern, 
+            ignore_eof=True)
+        if debug: print(name)
+        try:
+            return NameObject(name.decode('utf-8'))
+        except (UnicodeEncodeError, UnicodeDecodeError) as e:
+            # Name objects should represent irregular characters
+            # with a '#' followed by the symbol's hex number
+            if not pdf.strict:
+                warnings.warn("Illegal character in Name Object", utils.PdfReadWarning)
+                return NameObject(name)
+            else:
+                raise utils.PdfReadError("Illegal character in Name Object")
+
+    readFromStream = staticmethod(readFromStream)
+
+
+class DictionaryObject(dict, PdfObject):
+    def raw_get(self, key):
+        return dict.__getitem__(self, key)
+
+    def __setitem__(self, key, value):
+        if not isinstance(key, PdfObject):
+            raise ValueError("key must be PdfObject")
+        if not isinstance(value, PdfObject):
+            raise ValueError("value must be PdfObject")
+        return dict.__setitem__(self, key, value)
+
+    def setdefault(self, key, value=None):
+        if not isinstance(key, PdfObject):
+            raise ValueError("key must be PdfObject")
+        if not isinstance(value, PdfObject):
+            raise ValueError("value must be PdfObject")
+        return dict.setdefault(self, key, value)
+
+    def __getitem__(self, key):
+        return dict.__getitem__(self, key).getObject()
+
+    ##
+    # Retrieves XMP (Extensible Metadata Platform) data relevant to the
+    # this object, if available.
+    # <p>
+    # Stability: Added in v1.12, will exist for all future v1.x releases.
+    # @return Returns a {@link #xmp.XmpInformation XmlInformation} instance
+    # that can be used to access XMP metadata from the document.  Can also
+    # return None if no metadata was found on the document root.
+    def getXmpMetadata(self):
+        metadata = self.get("/Metadata", None)
+        if metadata == None:
+            return None
+        metadata = metadata.getObject()
+        from . import xmp
+        if not isinstance(metadata, xmp.XmpInformation):
+            metadata = xmp.XmpInformation(metadata)
+            self[NameObject("/Metadata")] = metadata
+        return metadata
+
+    ##
+    # Read-only property that accesses the {@link
+    # #DictionaryObject.getXmpData getXmpData} function.
+    # <p>
+    # Stability: Added in v1.12, will exist for all future v1.x releases.
+    xmpMetadata = property(lambda self: self.getXmpMetadata(), None, None)
+
+    def writeToStream(self, stream, encryption_key):
+        stream.write(b_("<<\n"))
+        for key, value in list(self.items()):
+            key.writeToStream(stream, encryption_key)
+            stream.write(b_(" "))
+            value.writeToStream(stream, encryption_key)
+            stream.write(b_("\n"))
+        stream.write(b_(">>"))
+
+    def readFromStream(stream, pdf):
+        debug = False
+        tmp = stream.read(2)
+        if tmp != b_("<<"):
+            raise utils.PdfReadError("Dictionary read error at byte %s: stream must begin with '<<'" % utils.hexStr(stream.tell()))
+        data = {}
+        while True:
+            tok = readNonWhitespace(stream)
+            if tok == b_('\x00'):
+                continue
+            elif tok == b_('%'):
+                stream.seek(-1, 1)
+                skipOverComment(stream)
+                continue
+            if not tok:
+                # stream has truncated prematurely
+                raise PdfStreamError("Stream has ended unexpectedly")
+
+            if debug: print(("Tok:", tok))
+            if tok == b_(">"):
+                stream.read(1)
+                break
+            stream.seek(-1, 1)
+            key = readObject(stream, pdf)
+            tok = readNonWhitespace(stream)
+            stream.seek(-1, 1)
+            value = readObject(stream, pdf)
+            if not data.get(key):
+                data[key] = value
+            elif pdf.strict:
+                # multiple definitions of key not permitted
+                raise utils.PdfReadError("Multiple definitions in dictionary at byte %s for key %s" \
+                                           % (utils.hexStr(stream.tell()), key))
+            else:
+                warnings.warn("Multiple definitions in dictionary at byte %s for key %s" \
+                                           % (utils.hexStr(stream.tell()), key), utils.PdfReadWarning)
+
+        pos = stream.tell()
+        s = readNonWhitespace(stream)
+        if s == b_('s') and stream.read(5) == b_('tream'):
+            eol = stream.read(1)
+            # odd PDF file output has spaces after 'stream' keyword but before EOL.
+            # patch provided by Danial Sandler
+            while eol == b_(' '):
+                eol = stream.read(1)
+            assert eol in (b_("\n"), b_("\r"))
+            if eol == b_("\r"):
+                # read \n after
+                if stream.read(1)  != b_('\n'):
+                    stream.seek(-1, 1)
+            # this is a stream object, not a dictionary
+            assert "/Length" in data
+            length = data["/Length"]
+            if debug: print(data)
+            if isinstance(length, IndirectObject):
+                t = stream.tell()
+                length = pdf.getObject(length)
+                stream.seek(t, 0)
+            data["__streamdata__"] = stream.read(length)
+            if debug: print("here")
+            #if debug: print(binascii.hexlify(data["__streamdata__"]))
+            e = readNonWhitespace(stream)
+            ndstream = stream.read(8)
+            if (e + ndstream) != b_("endstream"):
+                # (sigh) - the odd PDF file has a length that is too long, so
+                # we need to read backwards to find the "endstream" ending.
+                # ReportLab (unknown version) generates files with this bug,
+                # and Python users into PDF files tend to be our audience.
+                # we need to do this to correct the streamdata and chop off
+                # an extra character.
+                pos = stream.tell()
+                stream.seek(-10, 1)
+                end = stream.read(9)
+                if end == b_("endstream"):
+                    # we found it by looking back one character further.
+                    data["__streamdata__"] = data["__streamdata__"][:-1]
+                else:
+                    if debug: print(("E", e, ndstream, debugging.toHex(end)))
+                    stream.seek(pos, 0)
+                    raise utils.PdfReadError("Unable to find 'endstream' marker after stream at byte %s." % utils.hexStr(stream.tell()))
+        else:
+            stream.seek(pos, 0)
+        if "__streamdata__" in data:
+            return StreamObject.initializeFromDictionary(data)
+        else:
+            retval = DictionaryObject()
+            retval.update(data)
+            return retval
+    readFromStream = staticmethod(readFromStream)
+
+
+class TreeObject(DictionaryObject):
+    def __init__(self):
+        DictionaryObject.__init__(self)
+
+    def hasChildren(self):
+        return '/First' in self
+
+    def __iter__(self):
+        return self.children()
+
+    def children(self):
+        if not self.hasChildren():
+            raise StopIteration
+
+        child = self['/First']
+        while True:
+            yield child
+            if child == self['/Last']:
+                raise StopIteration
+            child = child['/Next']
+
+    def addChild(self, child, pdf):
+        childObj = child.getObject()
+        child = pdf.getReference(childObj)
+        assert isinstance(child, IndirectObject)
+
+        if '/First' not in self:
+            self[NameObject('/First')] = child
+            self[NameObject('/Count')] = NumberObject(0)
+            prev = None
+        else:
+            prev = self['/Last']
+
+        self[NameObject('/Last')] = child
+        self[NameObject('/Count')] = NumberObject(self[NameObject('/Count')] + 1)
+
+        if prev:
+            prevRef = pdf.getReference(prev)
+            assert isinstance(prevRef, IndirectObject)
+            childObj[NameObject('/Prev')] = prevRef
+            prev[NameObject('/Next')] = child
+
+        parentRef = pdf.getReference(self)
+        assert isinstance(parentRef, IndirectObject)
+        childObj[NameObject('/Parent')] = parentRef
+
+    def removeChild(self, child):
+        childObj = child.getObject()
+
+        if NameObject('/Parent') not in childObj:
+            raise ValueError("Removed child does not appear to be a tree item")
+        elif childObj[NameObject('/Parent')] != self:
+            raise ValueError("Removed child is not a member of this tree")
+
+        found = False
+        prevRef = None
+        prev = None
+        curRef = self[NameObject('/First')]
+        cur = curRef.getObject()
+        lastRef = self[NameObject('/Last')]
+        last = lastRef.getObject()
+        while cur != None:
+            if cur == childObj:
+                if prev == None:
+                    if NameObject('/Next') in cur:
+                        # Removing first tree node
+                        nextRef = cur[NameObject('/Next')]
+                        next = nextRef.getObject()
+                        del next[NameObject('/Prev')]
+                        self[NameObject('/First')] = nextRef
+                        self[NameObject('/Count')] = self[NameObject('/Count')] - 1
+
+                    else:
+                        # Removing only tree node
+                        assert self[NameObject('/Count')] == 1
+                        del self[NameObject('/Count')]
+                        del self[NameObject('/First')]
+                        if NameObject('/Last') in self:
+                            del self[NameObject('/Last')]
+                else:
+                    if NameObject('/Next') in cur:
+                        # Removing middle tree node
+                        nextRef = cur[NameObject('/Next')]
+                        next = nextRef.getObject()
+                        next[NameObject('/Prev')] = prevRef
+                        prev[NameObject('/Next')] = nextRef
+                        self[NameObject('/Count')] = self[NameObject('/Count')] - 1
+                    else:
+                        # Removing last tree node
+                        assert cur == last
+                        del prev[NameObject('/Next')]
+                        self[NameObject('/Last')] = prevRef
+                        self[NameObject('/Count')] = self[NameObject('/Count')] - 1
+                found = True
+                break
+
+            prevRef = curRef
+            prev = cur
+            if NameObject('/Next') in cur:
+                curRef = cur[NameObject('/Next')]
+                cur = curRef.getObject()
+            else:
+                curRef = None
+                cur = None
+
+        if not found:
+            raise ValueError("Removal couldn't find item in tree")
+
+        del childObj[NameObject('/Parent')]
+        if NameObject('/Next') in childObj:
+            del childObj[NameObject('/Next')]
+        if NameObject('/Prev') in childObj:
+            del childObj[NameObject('/Prev')]
+
+    def emptyTree(self):
+        for child in self:
+            childObj = child.getObject()
+            del childObj[NameObject('/Parent')]
+            if NameObject('/Next') in childObj:
+                del childObj[NameObject('/Next')]
+            if NameObject('/Prev') in childObj:
+                del childObj[NameObject('/Prev')]
+
+        if NameObject('/Count') in self:
+            del self[NameObject('/Count')]
+        if NameObject('/First') in self:
+            del self[NameObject('/First')]
+        if NameObject('/Last') in self:
+            del self[NameObject('/Last')]
+
+
+class StreamObject(DictionaryObject):
+    def __init__(self):
+        self._data = None
+        self.decodedSelf = None
+
+    def writeToStream(self, stream, encryption_key):
+        self[NameObject("/Length")] = NumberObject(len(self._data))
+        DictionaryObject.writeToStream(self, stream, encryption_key)
+        del self["/Length"]
+        stream.write(b_("\nstream\n"))
+        data = self._data
+        if encryption_key:
+            data = RC4_encrypt(encryption_key, data)
+        stream.write(data)
+        stream.write(b_("\nendstream"))
+
+    def initializeFromDictionary(data):
+        if "/Filter" in data:
+            retval = EncodedStreamObject()
+        else:
+            retval = DecodedStreamObject()
+        retval._data = data["__streamdata__"]
+        del data["__streamdata__"]
+        del data["/Length"]
+        retval.update(data)
+        return retval
+    initializeFromDictionary = staticmethod(initializeFromDictionary)
+
+    def flateEncode(self):
+        if "/Filter" in self:
+            f = self["/Filter"]
+            if isinstance(f, ArrayObject):
+                f.insert(0, NameObject("/FlateDecode"))
+            else:
+                newf = ArrayObject()
+                newf.append(NameObject("/FlateDecode"))
+                newf.append(f)
+                f = newf
+        else:
+            f = NameObject("/FlateDecode")
+        retval = EncodedStreamObject()
+        retval[NameObject("/Filter")] = f
+        retval._data = filters.FlateDecode.encode(self._data)
+        return retval
+
+
+class DecodedStreamObject(StreamObject):
+    def getData(self):
+        return self._data
+
+    def setData(self, data):
+        self._data = data
+
+
+class EncodedStreamObject(StreamObject):
+    def __init__(self):
+        self.decodedSelf = None
+
+    def getData(self):
+        if self.decodedSelf:
+            # cached version of decoded object
+            return self.decodedSelf.getData()
+        else:
+            # create decoded object
+            decoded = DecodedStreamObject()
+
+            decoded._data = filters.decodeStreamData(self)
+            for key, value in list(self.items()):
+                if not key in ("/Length", "/Filter", "/DecodeParms"):
+                    decoded[key] = value
+            self.decodedSelf = decoded
+            return decoded._data
+
+    def setData(self, data):
+        raise utils.PdfReadError("Creating EncodedStreamObject is not currently supported")
+
+
+class RectangleObject(ArrayObject):
+    """
+    This class is used to represent *page boxes* in PyPDF2. These boxes include:
+
+        * :attr:`artBox <PyPDF2.pdf.PageObject.artBox>`
+        * :attr:`bleedBox <PyPDF2.pdf.PageObject.bleedBox>`
+        * :attr:`cropBox <PyPDF2.pdf.PageObject.cropBox>`
+        * :attr:`mediaBox <PyPDF2.pdf.PageObject.mediaBox>`
+        * :attr:`trimBox <PyPDF2.pdf.PageObject.trimBox>`
+    """
+    def __init__(self, arr):
+        # must have four points
+        assert len(arr) == 4
+        # automatically convert arr[x] into NumberObject(arr[x]) if necessary
+        ArrayObject.__init__(self, [self.ensureIsNumber(x) for x in arr])
+
+    def ensureIsNumber(self, value):
+        if not isinstance(value, (NumberObject, FloatObject)):
+            value = FloatObject(value)
+        return value
+
+    def __repr__(self):
+        return "RectangleObject(%s)" % repr(list(self))
+
+    def getLowerLeft_x(self):
+        return self[0]
+
+    def getLowerLeft_y(self):
+        return self[1]
+
+    def getUpperRight_x(self):
+        return self[2]
+
+    def getUpperRight_y(self):
+        return self[3]
+
+    def getUpperLeft_x(self):
+        return self.getLowerLeft_x()
+
+    def getUpperLeft_y(self):
+        return self.getUpperRight_y()
+
+    def getLowerRight_x(self):
+        return self.getUpperRight_x()
+
+    def getLowerRight_y(self):
+        return self.getLowerLeft_y()
+
+    def getLowerLeft(self):
+        return self.getLowerLeft_x(), self.getLowerLeft_y()
+
+    def getLowerRight(self):
+        return self.getLowerRight_x(), self.getLowerRight_y()
+
+    def getUpperLeft(self):
+        return self.getUpperLeft_x(), self.getUpperLeft_y()
+
+    def getUpperRight(self):
+        return self.getUpperRight_x(), self.getUpperRight_y()
+
+    def setLowerLeft(self, value):
+        self[0], self[1] = [self.ensureIsNumber(x) for x in value]
+
+    def setLowerRight(self, value):
+        self[2], self[1] = [self.ensureIsNumber(x) for x in value]
+
+    def setUpperLeft(self, value):
+        self[0], self[3] = [self.ensureIsNumber(x) for x in value]
+
+    def setUpperRight(self, value):
+        self[2], self[3] = [self.ensureIsNumber(x) for x in value]
+
+    def getWidth(self):
+        return self.getUpperRight_x() - self.getLowerLeft_x()
+
+    def getHeight(self):
+        return self.getUpperRight_y() - self.getLowerLeft_y()
+
+    lowerLeft = property(getLowerLeft, setLowerLeft, None, None)
+    """
+    Property to read and modify the lower left coordinate of this box
+    in (x,y) form.
+    """
+    lowerRight = property(getLowerRight, setLowerRight, None, None)
+    """
+    Property to read and modify the lower right coordinate of this box
+    in (x,y) form.
+    """
+    upperLeft = property(getUpperLeft, setUpperLeft, None, None)
+    """
+    Property to read and modify the upper left coordinate of this box
+    in (x,y) form.
+    """
+    upperRight = property(getUpperRight, setUpperRight, None, None)
+    """
+    Property to read and modify the upper right coordinate of this box
+    in (x,y) form.
+    """
+
+
+class Field(TreeObject):
+    """
+    A class representing a field dictionary. This class is accessed through
+    :meth:`getFields()<PyPDF2.PdfFileReader.getFields>`
+    """
+    def __init__(self, data):
+        DictionaryObject.__init__(self)
+        attributes = ("/FT", "/Parent", "/Kids", "/T", "/TU", "/TM", "/Ff",
+                      "/V", "/DV", "/AA")
+        for attr in attributes:
+            try:
+                self[NameObject(attr)] = data[attr]
+            except KeyError:
+                pass
+
+    fieldType = property(lambda self: self.get("/FT"))
+    """
+    Read-only property accessing the type of this field.
+    """
+
+    parent = property(lambda self: self.get("/Parent"))
+    """
+    Read-only property accessing the parent of this field.
+    """
+
+    kids = property(lambda self: self.get("/Kids"))
+    """
+    Read-only property accessing the kids of this field.
+    """
+
+    name = property(lambda self: self.get("/T"))
+    """
+    Read-only property accessing the name of this field.
+    """
+
+    altName = property(lambda self: self.get("/TU"))
+    """
+    Read-only property accessing the alternate name of this field.
+    """
+
+    mappingName = property(lambda self: self.get("/TM"))
+    """
+    Read-only property accessing the mapping name of this field. This
+    name is used by PyPDF2 as a key in the dictionary returned by
+    :meth:`getFields()<PyPDF2.PdfFileReader.getFields>`
+    """
+
+    flags = property(lambda self: self.get("/Ff"))
+    """
+    Read-only property accessing the field flags, specifying various
+    characteristics of the field (see Table 8.70 of the PDF 1.7 reference).
+    """
+
+    value = property(lambda self: self.get("/V"))
+    """
+    Read-only property accessing the value of this field. Format
+    varies based on field type.
+    """
+
+    defaultValue = property(lambda self: self.get("/DV"))
+    """
+    Read-only property accessing the default value of this field.
+    """
+
+    additionalActions = property(lambda self: self.get("/AA"))
+    """
+    Read-only property accessing the additional actions dictionary.
+    This dictionary defines the field's behavior in response to trigger events.
+    See Section 8.5.2 of the PDF 1.7 reference.
+    """
+
+
+class Destination(TreeObject):
+    """
+    A class representing a destination within a PDF file.
+    See section 8.2.1 of the PDF 1.6 reference.
+
+    :param str title: Title of this destination.
+    :param int page: Page number of this destination.
+    :param str typ: How the destination is displayed.
+    :param args: Additional arguments may be necessary depending on the type.
+    :raises PdfReadError: If destination type is invalid.
+
+    Valid ``typ`` arguments (see PDF spec for details):
+             /Fit       No additional arguments
+             /XYZ       [left] [top] [zoomFactor]
+             /FitH      [top]
+             /FitV      [left]
+             /FitR      [left] [bottom] [right] [top]
+             /FitB      No additional arguments
+             /FitBH     [top]
+             /FitBV     [left]
+    """
+    def __init__(self, title, page, typ, *args):
+        DictionaryObject.__init__(self)
+        self[NameObject("/Title")] = title
+        self[NameObject("/Page")] = page
+        self[NameObject("/Type")] = typ
+
+        # from table 8.2 of the PDF 1.7 reference.
+        if typ == "/XYZ":
+            (self[NameObject("/Left")], self[NameObject("/Top")],
+                self[NameObject("/Zoom")]) = args
+        elif typ == "/FitR":
+            (self[NameObject("/Left")], self[NameObject("/Bottom")],
+                self[NameObject("/Right")], self[NameObject("/Top")]) = args
+        elif typ in ["/FitH", "/FitBH"]:
+            self[NameObject("/Top")], = args
+        elif typ in ["/FitV", "/FitBV"]:
+            self[NameObject("/Left")], = args
+        elif typ in ["/Fit", "/FitB"]:
+            pass
+        else:
+            raise utils.PdfReadError("Unknown Destination Type: %r" % typ)
+
+    def getDestArray(self):
+        return ArrayObject([self.raw_get('/Page'), self['/Type']] + [self[x] for x in ['/Left', '/Bottom', '/Right', '/Top', '/Zoom'] if x in self])
+
+    def writeToStream(self, stream, encryption_key):
+        stream.write(b_("<<\n"))
+        key = NameObject('/D')
+        key.writeToStream(stream, encryption_key)
+        stream.write(b_(" "))
+        value = self.getDestArray()
+        value.writeToStream(stream, encryption_key)
+
+        key = NameObject("/S")
+        key.writeToStream(stream, encryption_key)
+        stream.write(b_(" "))
+        value = NameObject("/GoTo")
+        value.writeToStream(stream, encryption_key)
+
+        stream.write(b_("\n"))
+        stream.write(b_(">>"))
+
+    title = property(lambda self: self.get("/Title"))
+    """
+    Read-only property accessing the destination title.
+
+    :rtype: str
+    """
+
+    page = property(lambda self: self.get("/Page"))
+    """
+    Read-only property accessing the destination page number.
+
+    :rtype: int
+    """
+
+    typ = property(lambda self: self.get("/Type"))
+    """
+    Read-only property accessing the destination type.
+
+    :rtype: str
+    """
+
+    zoom = property(lambda self: self.get("/Zoom", None))
+    """
+    Read-only property accessing the zoom factor.
+
+    :rtype: int, or ``None`` if not available.
+    """
+
+    left = property(lambda self: self.get("/Left", None))
+    """
+    Read-only property accessing the left horizontal coordinate.
+
+    :rtype: int, or ``None`` if not available.
+    """
+
+    right = property(lambda self: self.get("/Right", None))
+    """
+    Read-only property accessing the right horizontal coordinate.
+
+    :rtype: int, or ``None`` if not available.
+    """
+
+    top = property(lambda self: self.get("/Top", None))
+    """
+    Read-only property accessing the top vertical coordinate.
+
+    :rtype: int, or ``None`` if not available.
+    """
+
+    bottom = property(lambda self: self.get("/Bottom", None))
+    """
+    Read-only property accessing the bottom vertical coordinate.
+
+    :rtype: int, or ``None`` if not available.
+    """
+
+
+class Bookmark(Destination):
+    def writeToStream(self, stream, encryption_key):
+        stream.write(b_("<<\n"))
+        for key in [NameObject(x) for x in ['/Title', '/Parent', '/First', '/Last', '/Next', '/Prev'] if x in self]:
+            key.writeToStream(stream, encryption_key)
+            stream.write(b_(" "))
+            value = self.raw_get(key)
+            value.writeToStream(stream, encryption_key)
+            stream.write(b_("\n"))
+        key = NameObject('/Dest')
+        key.writeToStream(stream, encryption_key)
+        stream.write(b_(" "))
+        value = self.getDestArray()
+        value.writeToStream(stream, encryption_key)
+        stream.write(b_("\n"))
+        stream.write(b_(">>"))
+
+
+def encode_pdfdocencoding(unicode_string):
+    retval = b_('')
+    for c in unicode_string:
+        try:
+            retval += b_(chr(_pdfDocEncoding_rev[c]))
+        except KeyError:
+            raise UnicodeEncodeError("pdfdocencoding", c, -1, -1,
+                    "does not exist in translation table")
+    return retval
+
+
+def decode_pdfdocencoding(byte_array):
+    retval = u_('')
+    for b in byte_array:
+        c = _pdfDocEncoding[ord_(b)]
+        if c == u_('\u0000'):
+            raise UnicodeDecodeError("pdfdocencoding", utils.barray(b), -1, -1,
+                    "does not exist in translation table")
+        retval += c
+    return retval
+
+_pdfDocEncoding = (
+  u_('\u0000'), u_('\u0000'), u_('\u0000'), u_('\u0000'), u_('\u0000'), u_('\u0000'), u_('\u0000'), u_('\u0000'),
+  u_('\u0000'), u_('\u0000'), u_('\u0000'), u_('\u0000'), u_('\u0000'), u_('\u0000'), u_('\u0000'), u_('\u0000'),
+  u_('\u0000'), u_('\u0000'), u_('\u0000'), u_('\u0000'), u_('\u0000'), u_('\u0000'), u_('\u0000'), u_('\u0000'),
+  u_('\u02d8'), u_('\u02c7'), u_('\u02c6'), u_('\u02d9'), u_('\u02dd'), u_('\u02db'), u_('\u02da'), u_('\u02dc'),
+  u_('\u0020'), u_('\u0021'), u_('\u0022'), u_('\u0023'), u_('\u0024'), u_('\u0025'), u_('\u0026'), u_('\u0027'),
+  u_('\u0028'), u_('\u0029'), u_('\u002a'), u_('\u002b'), u_('\u002c'), u_('\u002d'), u_('\u002e'), u_('\u002f'),
+  u_('\u0030'), u_('\u0031'), u_('\u0032'), u_('\u0033'), u_('\u0034'), u_('\u0035'), u_('\u0036'), u_('\u0037'),
+  u_('\u0038'), u_('\u0039'), u_('\u003a'), u_('\u003b'), u_('\u003c'), u_('\u003d'), u_('\u003e'), u_('\u003f'),
+  u_('\u0040'), u_('\u0041'), u_('\u0042'), u_('\u0043'), u_('\u0044'), u_('\u0045'), u_('\u0046'), u_('\u0047'),
+  u_('\u0048'), u_('\u0049'), u_('\u004a'), u_('\u004b'), u_('\u004c'), u_('\u004d'), u_('\u004e'), u_('\u004f'),
+  u_('\u0050'), u_('\u0051'), u_('\u0052'), u_('\u0053'), u_('\u0054'), u_('\u0055'), u_('\u0056'), u_('\u0057'),
+  u_('\u0058'), u_('\u0059'), u_('\u005a'), u_('\u005b'), u_('\u005c'), u_('\u005d'), u_('\u005e'), u_('\u005f'),
+  u_('\u0060'), u_('\u0061'), u_('\u0062'), u_('\u0063'), u_('\u0064'), u_('\u0065'), u_('\u0066'), u_('\u0067'),
+  u_('\u0068'), u_('\u0069'), u_('\u006a'), u_('\u006b'), u_('\u006c'), u_('\u006d'), u_('\u006e'), u_('\u006f'),
+  u_('\u0070'), u_('\u0071'), u_('\u0072'), u_('\u0073'), u_('\u0074'), u_('\u0075'), u_('\u0076'), u_('\u0077'),
+  u_('\u0078'), u_('\u0079'), u_('\u007a'), u_('\u007b'), u_('\u007c'), u_('\u007d'), u_('\u007e'), u_('\u0000'),
+  u_('\u2022'), u_('\u2020'), u_('\u2021'), u_('\u2026'), u_('\u2014'), u_('\u2013'), u_('\u0192'), u_('\u2044'),
+  u_('\u2039'), u_('\u203a'), u_('\u2212'), u_('\u2030'), u_('\u201e'), u_('\u201c'), u_('\u201d'), u_('\u2018'),
+  u_('\u2019'), u_('\u201a'), u_('\u2122'), u_('\ufb01'), u_('\ufb02'), u_('\u0141'), u_('\u0152'), u_('\u0160'),
+  u_('\u0178'), u_('\u017d'), u_('\u0131'), u_('\u0142'), u_('\u0153'), u_('\u0161'), u_('\u017e'), u_('\u0000'),
+  u_('\u20ac'), u_('\u00a1'), u_('\u00a2'), u_('\u00a3'), u_('\u00a4'), u_('\u00a5'), u_('\u00a6'), u_('\u00a7'),
+  u_('\u00a8'), u_('\u00a9'), u_('\u00aa'), u_('\u00ab'), u_('\u00ac'), u_('\u0000'), u_('\u00ae'), u_('\u00af'),
+  u_('\u00b0'), u_('\u00b1'), u_('\u00b2'), u_('\u00b3'), u_('\u00b4'), u_('\u00b5'), u_('\u00b6'), u_('\u00b7'),
+  u_('\u00b8'), u_('\u00b9'), u_('\u00ba'), u_('\u00bb'), u_('\u00bc'), u_('\u00bd'), u_('\u00be'), u_('\u00bf'),
+  u_('\u00c0'), u_('\u00c1'), u_('\u00c2'), u_('\u00c3'), u_('\u00c4'), u_('\u00c5'), u_('\u00c6'), u_('\u00c7'),
+  u_('\u00c8'), u_('\u00c9'), u_('\u00ca'), u_('\u00cb'), u_('\u00cc'), u_('\u00cd'), u_('\u00ce'), u_('\u00cf'),
+  u_('\u00d0'), u_('\u00d1'), u_('\u00d2'), u_('\u00d3'), u_('\u00d4'), u_('\u00d5'), u_('\u00d6'), u_('\u00d7'),
+  u_('\u00d8'), u_('\u00d9'), u_('\u00da'), u_('\u00db'), u_('\u00dc'), u_('\u00dd'), u_('\u00de'), u_('\u00df'),
+  u_('\u00e0'), u_('\u00e1'), u_('\u00e2'), u_('\u00e3'), u_('\u00e4'), u_('\u00e5'), u_('\u00e6'), u_('\u00e7'),
+  u_('\u00e8'), u_('\u00e9'), u_('\u00ea'), u_('\u00eb'), u_('\u00ec'), u_('\u00ed'), u_('\u00ee'), u_('\u00ef'),
+  u_('\u00f0'), u_('\u00f1'), u_('\u00f2'), u_('\u00f3'), u_('\u00f4'), u_('\u00f5'), u_('\u00f6'), u_('\u00f7'),
+  u_('\u00f8'), u_('\u00f9'), u_('\u00fa'), u_('\u00fb'), u_('\u00fc'), u_('\u00fd'), u_('\u00fe'), u_('\u00ff')
+)
+
+assert len(_pdfDocEncoding) == 256
+
+_pdfDocEncoding_rev = {}
+for i in range(256):
+    char = _pdfDocEncoding[i]
+    if char == u_("\u0000"):
+        continue
+    assert char not in _pdfDocEncoding_rev
+    _pdfDocEncoding_rev[char] = i