./print/qpdf, Structural, content-preserving transformations on PDF files

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Branch: CURRENT, Version: 8.4.1, Package name: qpdf-8.4.1, Maintainer: pkgsrc-users

QPDF is a command-line program that does structural, content-preserving
transformations on PDF files. It could have been called something like
pdf-to-pdf. It also provides many useful capabilities to developers of
PDF-producing software or for people who just want to look at the innards of a
PDF file to learn more about how they work.

QPDF is capable of creating linearized (also known as web-optimized) files and
encrypted files. It is also capable of converting PDF files with object streams
(also known as compressed objects) to files with no compressed objects or to
generate object streams from files that don't have them (or even those that
already do). QPDF also supports a special mode designed to allow you to edit the
content of PDF files in a text editor. For more details, please see the
documentation links below.

QPDF includes support for merging and splitting PDFs through the ability to copy
objects from one PDF file into another and to manipulate the list of pages in a
PDF file. The QPDF library also makes it possible for you to create PDF files
from scratch. In this mode, you are responsible for supplying all the contents
of the file, while the QPDF library takes care off all the syntactical
representation of the objects, creation of cross references tables and, if you
use them, object streams, encryption, linearization and other syntactic details.

Required to run:
[graphics/jpeg] [lang/perl5] [devel/pcre]

Required to build:

Master sites:

SHA1: bb7e6ee3b9b515b873366fc85d14bcdf00853bb8
RMD160: 572331148259ee520f3c09b7b2576ab6229ee6c4
Filesize: 16592.531 KB

Version history: (Expand)

CVS history: (Expand)

   2019-05-02 13:25:23 by Ryo ONODERA | Files touched by this commit (2) | Package updated
Log message:
Update to 8.4.1

This is qpdf version 8.4.1. It contains a small handful of minor
CLI enhancements and a few bug fixes from 8.4.0 including handling
of Unicode filenames in Windows, a performance bug with --split-pages
and a few others. For a full list of changes, please see the release
   2019-04-27 05:12:41 by Ryo ONODERA | Files touched by this commit (2) | Package updated
Log message:
Update to 8.4.0

This is qpdf version 8.4.0. It contains many enhancements and fixes
including better handling of Unicode passwords, enhancements to
image optimization and appearance generation, overlay/underlay and
other changes. It also includes an important bug fix for page
splitting. For a full list of changes, please see the release notes.
   2019-01-08 17:29:33 by Ryo ONODERA | Files touched by this commit (4) | Package updated
Log message:
Update to 8.3.0

2019-01-07  Jay Berkenbilt  <ejb@ql.org>

	* 8.3.0: release

	* Add sample completion files in completions. These can be used by
	packagers to install on the system wherever bash and zsh keep
	their vendor-supplied completions.

	* Add configure flag --enable-check-autofiles, which is on by
	default. Packagers whose packaging systems automatically refresh
	autoconf or libtool files should pass --disable-check-autofiles to
	./configure to suppress warnings about automatically generated
	files being outdated.

2019-01-06  Jay Berkenbilt  <ejb@ql.org>

	* Remove the restriction in most cases that the source QPDF used
	in a copyForeignObject call has to stick around until the
	destination QPDF is written. The exceptional case is when the
	source stream gets is data using a
	QPDFObjectHandle::StreamDataProvider. For a more in-depth
	discussion, see comments around copyForeignObject in QPDF.hh.
	Fixes #219.

2019-01-05  Jay Berkenbilt  <ejb@ql.org>

	* When generating appearances, if the font uses one of the
	standard, built-in encodings, restrict the character set to that
	rather than just to ASCII. This will allow most appearances to
	contain characters from the ISO-Latin-1 range plus a few
	additional characters.

	* Add methods QUtil::utf8_to_win_ansi and

	* Add method QUtil::utf8_to_utf16.

2019-01-04  Jay Berkenbilt  <ejb@ql.org>

	* Add new option --optimize-images, which recompresses every image
	using DCT (JPEG) compression as long as the image is not already
	compressed with lossy compression and recompressing the image
	reduces its size. The additional options --oi-min-width,
	--oi-min-height, and --oi-min-area prevent recompression of images
	whose width, height, or pixel area (width * height) are below a
	specified threshold.

	* Add new option --collate. When specified, the semantics of
	--pages change from concatenation to collation. See the manual for
	a more detailed discussion. Fixes #259.

	* Add new method QPDFWriter::getFinalVersion, which returns the
	PDF version that will ultimately be written to the final file. See
	comments in QPDFWriter.hh for some restrictions on its use. Fixes

	* When unexpected errors are found while checking linearization
	data, print an error message instead of calling assert, which
	cause the program to crash. Fixes #209, #231.

	* Detect and recover from dangling references. If a PDF file
	contained an indirect reference to a non-existent object (which is
	valid), when adding a new object to the file, it was possible for
	the new object to take the object ID of the dangling reference,
	thereby causing the dangling reference to point to the new object.
	This case is now prevented. Fixes #240.

2019-01-03  Jay Berkenbilt  <ejb@ql.org>

        * Add --generate-appearances flag to the qpdf command-line tool to
	trigger generation of appearance streams.

	* Fix behavior of form field value setting to handle the following
	  - Strings are always written as UTF-16
	  - Check boxes and radio buttons are handled properly with
	    synchronization of values and appearance states

	* Define constants in qpdf/Constants.h for interpretation of
	annotation and form field flags

	* Add QPDFAnnotationObjectHelper::getFlags

	* Add many new methods to QPDFFormFieldObjectHelper for querying
	flags and field types

	* Add new methods for appearance stream generation. See comments
	in QPDFFormFieldObjectHelper.hh for generateAppearance() for a
	description of limitations.
	  - QPDFAcroFormDocumentHelper::generateAppearancesIfNeeded
	  - QPDFFormFieldObjectHelper::generateAppearance

	* Bug fix: when writing form field values, always write string
	values encoded as UTF-16.

	* Add method QUtil::utf8_to_ascii, which returns an ASCII string
	for a UTF-8 string, replacing out-of-range characters with a
	specified substitute.

2019-01-02  Jay Berkenbilt  <ejb@ql.org>

	* Add method QPDFObjectHandle::getResourceNames that returns a set
	of strings representing all second-level keys in a dictionary
	(i.e. all keys of all direct dictionary members).

2018-12-31  Jay Berkenbilt  <ejb@ql.org>

	* Add --flatten-annotations flag to the qpdf command-line tool for
	annotation flattening.

	* Add methods for flattening form fields and annotations:
	  - QPDFPageDocumentHelper::flattenAnnotations - integrate
	    annotation appearance streams into page contents with special
	    handling for form fields: if appearance streams are up to date
	    (/NeedAppearances is false in /AcroForm), the /AcroForm key of
	    the document catalog is removed. Otherwise, a warning is
	    issued, and form fields are ignored. Non-form-field
	    annotations are always flattened if an appearance stream can
	    be found.
	  - QPDFAnnotationObjectHelper::getPageContentForAppearance -
	    generate the content stream fragment to render an appearance
	    stream in a page's content stream as a form xobject. Called by

	* Add method QPDFObjectHandle::mergeResources(), which merges
	resource dictionaries. See detailed description in

	* Add QPDFObjectHandle::Matrix, similar to
	QPDFObjectHandle::Rectangle, as a convenience class for
	six-element arrays that are used as matrices.

2018-12-23  Jay Berkenbilt  <ejb@ql.org>

	* When specifying @arg on the command line, if the file "arg" does
	not exist, just treat this is a normal argument. This makes it
	easier to deal with files whose names start with the @ character.
	Fixes #265.

	* Tweak completion so it works with zsh as well using

2018-12-22  Jay Berkenbilt  <ejb@ql.org>

	* Add new options --json, --json-key, and --json-object to
	generate a json representation of the PDF file. This is described
	in more depth in the manual. You can also run qpdf --json-help to
	get a description of the json format.

2018-12-21  Jay Berkenbilt  <ejb@ql.org>

	* Allow --show-object=trailer for showing the document trailer.

	* You can now use eval $(qpdf --completion-bash) to enable bash
	completion for qpdf. It's not perfect, but it works pretty well.

2018-12-19  Jay Berkenbilt  <ejb@ql.org>

	* When splitting pages using --split-pages, the outlines
	dictionary and some supporting metadata are copied into the split
	files. The result is that all bookmarks from the original file
	appear, and those that point to pages that are preserved work
	while those that point to pages that are not preserved don't do
	anything. This is an interim step toward proper support for
	bookmark preservation in split files.

	* Add QPDFOutlineDocumentHelper and QPDFOutlineObjectHelper for
	handling outlines (bookmarks) including bidirectionally mapping
	between bookmarks and pages. Initially there is no support for
	modifying the outlines hierarchy.

2018-12-18  Jay Berkenbilt  <ejb@ql.org>

	* New method QPDFObjectHandle::getJSON() returns a JSON object
	with a partial representation of the object. See
	QPDFObjectHandle.hh for a detailed description.

	* Add a simple JSON serializer. This is not a complete or
	general-purpose JSON library. It allows assembly and serialization
	of JSON structures with some restrictions, which are described in
	the header file.

	* Add QPDFNameTreeObjectHelper class. This class provides useful
	methods for dealing with name trees, which are discussed in
	section 7.9.6 of the PDF spec (ISO-32000).

	* Preserve page labels when merging and splitting files. Prior
	versions of qpdf simply preserved the page label information from
	the first file, which usually wouldn't make any sense in the
	merged file. Now any page that had a page number in any original
	file will have the same page number after merging or splitting.

	* Add QPDFPageLabelDocumentHelper class. This is a document helper
	class that provides useful methods for dealing with page labels.
	It abstracts the fact that they are stored as number trees and
	deals with interpolating intermediate values that are not in the
	tree. It also has helper functions used by the qpdf command line
	tool to preserve page labels when merging and splitting files.

	* Add QPDFNumberTreeObjectHelper class. This class provides useful
	methods for dealing with number trees, which are discussed in
	section 7.9.7 of the PDF spec (ISO-32000). Page label dictionaries
	are represented as number trees.

	* New method QPDFObjectHandle::wrapInArray returns the object
	itself if it is an array. Otherwise, it returns an array
	containing the object. This is useful for dealing with PDF data
	that is sometimes expressed as a single element and sometimes
	expressed as an array, which is a somewhat common PDF idiom.

2018-10-11  Jay Berkenbilt  <ejb@ql.org>

	* Files generated by autogen.sh are now committed so that it is
	possible to build on platforms without autoconf directly from a
	clean checkout of the repository. The configure script detects if
	the files are out of date when it also determines that the tools
	are present to regenerate them.

	* Add build in Azure Pipelines, now that it is free for open
	source projects.
   2018-11-07 13:59:45 by Ryo ONODERA | Files touched by this commit (3) | Package updated
Log message:
Update to 8.2.1

This is qpdf version 8.2.1. It contains just a new command line flag to
the CLI. There are no library changes from 8.2.0.

This is qpdf version 8.2.0. It contains a few bug fixes and performance
improvements, some minor API enhancements, and a few other small changes.
   2018-08-22 11:48:07 by Thomas Klausner | Files touched by this commit (3558)
Log message:
Recursive bump for perl5-5.28.0
   2018-07-16 01:37:37 by Ryo ONODERA | Files touched by this commit (4) | Package updated
Log message:
Update to 8.1.0

8.1.0: June 23, 2018

        Usability Improvements

            When splitting files, qpdf detects fonts and images that the \ 
document metadata claims are referenced from a page but are not actually \ 
referenced and omits them from the output file. This change can cause a \ 
significant reduction in the size of split PDF files for files created by some \ 
software packages. Prior versions of qpdf would believe the document metadata \ 
and sometimes include all the images from all the other pages even though the \ 
pages were no longer present. In the unlikely event that the old behavior should \ 
be desired, it can be enabled by specifying --preserve-unreferenced-resources. \ 
For additional details, please see Section 3.6, “Advanced Transformation \ 

            When merging multiple PDF files, qpdf no longer leaves all the files \ 
open. This makes it possible to merge numbers of files that may exceed the \ 
operating system's limit for the maximum number of open files.

            The --rotate option's syntax has been extended to make the page \ 
range optional. If you specify --rotate=angle without specifying a page range, \ 
the rotation will be applied to all pages. This can be especially useful for \ 
adjusting a PDF created from a multi-page document that was scanned upside down.

            When merging multiple files, the --verbose option now prints \ 
information about each file as it operates on that file.

            When the --progress option is specified, qpdf will print a running \ 
indicator of its best guess at how far through the writing process it is. Note \ 
that, as with all progress meters, it's an approximation. This option is \ 
implemented in a way that makes it useful for software that uses the qpdf \ 
library; see API Enhancements below.

        Bug Fixes

            Properly decrypt files that use revision 3 of the standard security \ 
handler but use 40 bit keys (even though revision 3 supports 128-bit keys).

            Limit depth of nested data structures to prevent crashes from \ 
certain types of malformed (malicious) PDFs.

            In “newline before endstream” mode, insert the required extra \ 
newline before the endstream at the end of object streams. This one case was \ 
previously omitted.

        API Enhancements

            The first round of higher level “helper” interfaces has been \ 
introduced. These are designed to provide a more convenient way of interacting \ 
with certain document features than using QPDFObjectHandle directly. For details \ 
on helpers, see Section 6.3, “Helper Classes”. Specific additional \ 
interfaces are described below.

            Add two new document helper classes: QPDFPageDocumentHelper for \ 
working with pages, and QPDFAcroFormDocumentHelper for working with interactive \ 
forms. No old methods have been removed, but QPDFPageDocumentHelper is now the \ 
preferred way to perform operations on pages rather than calling the old methods \ 
in QPDFObjectHandle and QPDF directly. Comments in the header files direct you \ 
to the new interfaces. Please see the header files and ChangeLog for additional \ 

            Add three new object helper class: QPDFPageObjectHelper for pages, \ 
QPDFFormFieldObjectHelper for interactive form fields, and \ 
QPDFAnnotationObjectHelper for annotations. All three classes are fairly sparse \ 
at the moment, but they have some useful, basic functionality.

            A new example program examples/pdf-set-form-values.cc has been added \ 
that illustrates use of the new document and object helpers.

            The method QPDFWriter::registerProgressReporter has been added. This \ 
method allows you to register a function that is called by QPDFWriter to update \ 
your idea of the percentage it thinks it is through writing its output. Client \ 
programs can use this to implement reasonably accurate progress meters. The qpdf \ 
command line tool uses this to implement its --progress option.

            New methods QPDFObjectHandle::newUnicodeString and \ 
QPDFObject::unparseBinary have been added to allow for more convenient creation \ 
of strings that are explicitly encoded using big-endian UTF-16. This is useful \ 
for creating strings that appear outside of content streams, such as labels, \ 
form fields, outlines, document metadata, etc.

            A new class QPDFObjectHandle::Rectangle has been added to ease \ 
working with PDF rectangles, which are just arrays of four numeric values.
   2018-04-03 05:06:09 by Ryo ONODERA | Files touched by this commit (2) | Package updated
Log message:
Update to 8.0.2

Version 8.0.2 contains two small bug fixes: proper handling of pages
with no content, and better handling of files with loops following cross
reference tables.

This is a very minor update from 8.0.0. It just contains two small
enhancements that missed the train: handle zlib streams with data checksum
errors, and, in the command line tool, allow specification of page numbers
counting from the end in page ranges.
   2018-02-27 13:37:20 by Ryo ONODERA | Files touched by this commit (4) | Package updated
Log message:
Update to 8.0.0

2018-02-25  Jay Berkenbilt  <ejb@ql.org>

	* 8.0.0: release

2018-02-17  Jay Berkenbilt  <ejb@ql.org>

	* Fix QPDFObjectHandle::getUTF8Val() to properly handle strings
	that are encoded with PDF Doc Encoding. Fixes #179.

	* Add qpdf_check_pdf to the "C" API. This method just attempts to
	read the entire file and produce no output, making possible to
	assess whether the file has any errors that qpdf can detect.

	* Major enhancements to handling of type errors within the qpdf
	library. This fix is intended to eliminate those annoying cases
	where qpdf would exit with a message like "operation for
	dictionary object attemped on object of wrong type" without
	providing any context. Now qpdf keeps enough context to be able to
	issue a proper warning and to handle such conditions in a sensible
	way. This should greatly increase the number of bad files that
	qpdf can recover, and it should make it much easier to figure out
	what's broken when a file contains errors.

	* Error message fix: replace "file position" with "offset" in
	error messages that report lexical or parsing errors. Sometimes
	it's an offset in an object stream or a content stream rather than
	a file position, so this makes the error message less confusing in
	those cases. It still requires some knowledge to find the exact
	position of the error, since when it's not a file offset, it's
	probably an offset into a stream after uncompressing it.

	* Error message fix: correct some cases in which the object that
	contained a lexical error was omitted from the error message.

	* Error message fix: improve file name in the error message when
	there is a parser error inside an object stream.

2018-02-11  Jay Berkenbilt  <ejb@ql.org>

	* Add QPDFObjectHandle::filterPageContents method to provide a
	different interface for applying token filters to page contents
	without modifying the ultimate output.

2018-02-04  Jay Berkenbilt  <ejb@ql.org>

        * Changes listed on today's date are numerous and reflect
	significant enhancements to qpdf's lexical layer. While many
	nuances are discussed and a handful of small bugs were fixed, it
	should be emphasized that none of these issues have any impact on
	any output or behavior of qpdf under "normal" operation. There are
	some changes that have an effect on content stream normalization
	as with qdf mode or on code that interacts with PDF files
	lexically using QPDFTokenizer. There are no incompatible changes
	for normal operation. There are a few changes that will affect the
	exact error messages issued on certain bad files, and there is a
	small non-compatible enhancement regarding the behavior of
	manually constructed QPDFTokenizer::Token objects. Users of the
	qpdf command line tool will see no changes other than the addition
	of a new command-line flag and possibly some improved error

	* Significant lexer (tokenizer) enhancements. These are changes to
	the QPDFTokenizer class. These changes are of concern only to
	people who are operating with PDF files at the lexical layer using
	qpdf. They have little or no impact on most high-level interfaces
	or the command-line tool.

	New token types tt_space and tt_comment to recognize whitespace
	and comments. this makes it possible to tokenize a PDF file or
	stream and preserve everything about it.

	For backward compatibility, space and comment tokens are not
	returned by the tokenizer unless QPDFTokenizer.includeIgnorable()
	is called.

	Better handling of null bytes. These are now included in space
	tokens rather than being their own "tt_word" tokens. This should
	have no impact on any correct PDF file and has no impact on
	output, but it may change offsets in some error messages when
	trying to parse contents of bad files. Under default operation,
	qpdf does not attempt to parse content streams, so this change is
	mostly invisible.

	Bug fix to handling of bad tokens at ends of streams. Now, when
	allowEOF() has been called, these are treated as bad tokens
	(tt_bad or an exception, depending on invocation), and a
	separate tt_eof token is returned. Before the bad token
	contents were returned as the value of a tt_eof token. tt_eof
	tokens are always empty now.

	Fix a bug that would, on rare occasions, report the offset in an
	error message in the wrong space because of spaces or comments
	adjacent to a bad token.

	Clarify in comments exactly where the input source is positioned
	surrounding calls to readToken and getToken.

	* Add a new token type for inline images. This token type is only
	returned by QPDFTokenizer immediately following a call to
	expectInlineImage(). This change includes internal refactoring of
	a handful of places that all separately handled inline images, The
	logic of detecting inline images in content streams is now handled
	in one place in the code. Also we are more flexible about what
	characters may surround the EI operator that marks the end of an
	inline image.

	* New method QPDFObjectHandle::parsePageContents() to improve upon
	QPDFObjectHandle::parseContentStream(). The parseContentStream
	method used to operate on a single content stream, but was fixed
	to properly handle pages with contents split across multiple
	streams in an earlier release. The new method parsePageContents()
	can be called on the page object rather than the value of the
	page dictionary's /Contents key. This removes a few lines of
	boiler-plate code from any code that uses parseContentStream, and
	it also enables creation of more helpful error messages if
	problems are encountered as the error messages can include
	information about which page the streams come from.

	* Update content stream parsing example
	(examples/pdf-parse-content.cc) to use new
	QPDFObjectHandle::parsePageContents() method in favor of the older
	QPDFObjectHandle::parseContentStream() method.

	* Bug fix: change where the trailing newline is added to a stream
	in QDF mode when content normalization is enabled (the default for
	QDF mode). Before, the content normalizer ensured that the output
	ended with a trailing newline, but this had the undesired side
	effect of including the newline in the stream data for purposes of
	length computation. QPDFWriter already appends a newline without
	counting in length for better readability. Ordinarily this makes
	no difference, but in the rare case of a page's contents being
	split in the middle of a token, the old behavior could cause the
	extra newline to be interprted as part of the token. This bug
	could only be triggered in qdf mode, which is a mode intended for
	manual inspection of PDF files' contents, so it is very unlikely
	to have caused any actual problems for people using qpdf for
	production use. Even if it did, it would be very unusual for a PDF
	file to actually be adversely affected by this issue.

	* Add support for coalescing a page's contents into a single
	stream if they are represented as an array of streams. This can be
	performed from the command line using the --coalesce-contents
	option. Coalescing content streams can simplify things for
	software that wants to operate on a page's content streams without
	having to handle weird edge cases like content streams split in
	the middle of tokens. Note that
	QPDFObjectHandle::parsePageContents and
	QPDFObjectHandle::parseContentStream already handled split content
	streams. This is mainly to set the stage for new methods of
	operating on page contents. The new method
	QPDFObjectHandle::pipeContentStreams will pipe all of a page's
	content streams though a single pipeline. The new method
	QPDFObjectHandle.coalesceContentStreams, when called on a page
	object, will do nothing if the page's contents are a single
	stream, but if they are an array of streams, it will replace the
	page's contents with a single stream whose contents are the
	concatenation of the original streams.

	* A few library routines throw exceptions if called on non-page
	objects. These constraints have been relaxed somewhat to make qpdf
	more tolerant of files whose page dictionaries are not properly
	marked as such. Mostly exceptions about page operations being
	called on non page objects will only be thrown in cases where the
	operation had no chance of succeeding anyway. This change has no
	impact on any default mode operations, but it could allow
	applications that use page-level APIs in QPDFObjectHandle to be
	more tolerant of certain types of damaged files.

	* Add QPDFObjectHandle::TokenFilter class and methods to use it to
	perform lexical filtering on content streams. You can call
	QPDFObjectHandle::addTokenFilter on stream object, or you can call
	the higher level QPDFObjectHandle::addContentTokenFilter on a page
	object to cause the stream's contents to passed through a token
	filter while being retrieved by QPDFWriter or any other consumer.
	For details on using TokenFilter, please see comments in

	* Enhance the string, type QPDFTokenizer::Token constructor to
	initialize a raw value in addition to a value. Tokens have a
	value, which is a canonical representation, and a raw value. For
	all tokens except strings and names, the raw value and the value
	are the same. For strings, the value excludes the outer delimiters
	and has non-printing characters normalized. For names, the value
	resolves non-printing characters. In order to better facilitate
	token filters that mostly preserve contents and to enable
	developers to be mostly unconcerned about the nuances of token
	values and raw values, creating string and name tokens now
	properly handles this subtlety of values and raw values. When
	constructing string tokens, take care to avoid passing in the
	outer delimiters. This has always been the case, but it is now
	clarified in comments in QPDFObjectHandle.hh::TokenFilter. This
	has no impact on any existing code unless there's some code
	somewhere that was relying on Token::getRawValue() returning an
	empty string for a manually constructed token. The token class's
	operator== method still only looks at type and value, not raw
	value. For example, string tokens for <41> and (A) would still be
	equal because both are representations of the string "A".

	* Add QPDFObjectHandle::isDataModified method. This method just
	returns true if addTokenFilter has been called on the stream. It
	enables a caller to determine whether it is safe to optimize away
	piping of stream data in cases where the input and output are
	expected to be the same. QPDFWriter uses this internally to skip
	the optimization of not re-compressing already compressed streams
	if addTokenFilter has been called. Most developers will not have
	to worry about this as it is used internally in the library in the
	places that need it. If you are manually retrieving stream data
	with QPDFObjectHandle::getStreamData or
	QPDFObjectHandle::pipeStreamData, you don't need to worry about
	this at all.

	* Provide heavily annoated examples/pdf-filter-tokens.cc example
	that illustrates use of some simple token filters.

	* When normalizing content streams, as in qdf mode, issue warning
	about bad tokens. Content streams are only normalized when this is
	explicitly requested, so this has no impact on normal operation.
	However, in qdf mode, if qpdf detects a bad token, it means that
	either there's a bug in qpdf's lexer, that the file is damaged, or
	that the page's contents are split in a weird way. In any of those
	cases, qpdf could potentially damage the stream's contents by
	replacing carrige returns with newlines or otherwise messing with
	spaces. The mostly likely case of this would be an inline image's
	compressed data being divided across two streams and having the
	compressed data in the second stream contain a carriage return as
	part of its binary data. If you are using qdf mode just to look at
	PDF files in text editors, this usually doesn't matter. In cases
	of contents split across multiple streams, coalescing streams
	would eliminate the problem, so the warning mentions this. Prior
	to this enhancement, the chances of qdf mode writing incorrect
	data were already very low. This change should make it nearly
	impossible for qdf mode to unknowingly write invalid data.

2018-02-04  Jay Berkenbilt  <ejb@ql.org>

	* Add QPDFWriter::setLinearizationPass1Filename method and
	--linearize-pass1 command line option to allow specification of a
	file into which QPDFWriter will write its intermediate
	linearization pass 1 file. This is useful only for debugging qpdf.
	qpdf creates linearized files by computing the output in two
	passes. Ordinarily the first pass is discarded and not written
	anywhere. This option allows it to be inspected.