Using PDFs to manage and share content.
The balance between quality and size.
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White Paper
Whether you are trying to leverage the intellectual property that’s valuable to your organization, improve decision
making, increase sales opportunities or simply manage a vast amount of digital documents, the Portable Document
Format (PDF) is oft en the standard of choice. PDF delivers portable and consistent content, to both represent
your company and make it easy for a user to access your information. While PDF is the most consistently used
document type for long-format materials, it can sometimes provide challenges due to the wide variety and
inconsistencies in both authoring and consumption tools available.
Consider:
In 2014, 3,408 B2B companies were surveyed and the results published in the B2B Content Marketing Trends-
North America report from the Content Marketing Institute, MarketingProfs, 2014. According to the report,
respondents produced over 42,000 pieces of content per year to support content marketing eff orts. Of this
content 37% (or 15,692 assets) represent long form content such as eBooks, white papers, and case studies,
where the PDF works best to meet this need.
According to the article “PDF in 2016: Broader, Deeper, Richer”, from the PDF Association, Phil Ydens, Adobe
Systems VP of Engineering, had some interesting estimates to share during the 2015 PDF Technical Conference:
•
In October, 2015, there were approximately 1.6 billion PDF documents on the web. About 80% included the
string “2015”, implying that content is fairly current.
•
60% of non-image attachments in Outlook Exchange Enterprise are PDF documents.
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A conservative estimate is that 2.5 trillion PDF documents are created each year.
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PDF is the most popular format in cloud storage repositories; in many cases PDF is greater than 50% of the
fi les stored.
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17% of fi les in Box are PDF documents.
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18 billion PDF documents are in DropBox.
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73 million new PDF documents saved each day in Google Drive and Mail.
Adobe PDF and eBook technologies for Developers
Developed 24 years ago, PDF is the industry standard, and a leader when it comes to sharing information. Th e
PDF fi le format’s goal is to present document content reliably regardless of the soft ware, hardware, or operating
system in use, and is popular for use with long-form content. It is great for generating print-ready content,
and will open and display well on any workstation or laptop aft er being downloaded from a server, making it
an ideal choice when delivering content. However, once PDF became an ISO standard in 2008, and as more
vendors entered the market to create and use this royalty-free document format, the variety of PDF creation and
consumption tools on the market added a level of inconsistency to the process, and in some ways, reduced the
reliability and consistency of PDF fi les.
Th e popularity of the format and nearly global acceptance combined with the advent of open standards for PDF
creation means that hundreds, maybe even thousands, of soft ware products can now generate a PDF document.
With other added complexities, like variations in rendering, loose adherence to the PDF standard, and the
variety of PDF authoring and consumption tools available, PDF documents, now more than ever, can lack basic
consistency. Th is provides a challenge to content providers in appearance and reliability. As gloomy as this
message seems, it is possible to minimize these and other issues related to PDF content and provide fl awless
representation of your brand along with the ease of use that users expect from PDFs.
Take content marketing, for example. According to the Content Marketing Institute’s 2016 B2B/B2C Content
Marketing Trends Report, 70% of a buyer’s journey is complete before a buyer reaches out to sales. As a result,
marketers are now looking to deliver information that makes prospective buyers more intelligent about their
products. Because of that, businesses are focusing on delivering valuable information, in a consistent format,
across all platforms, and need to make sure that this information is easy to download, easy to open, the right size
for emailing, as well as impeccably represents their brand.
Information is most eff ective when it is written, designed and distributed in a manner that is appropriate for
a specifi c reader. Th at’s why it is important to consider not only what you’re saying, but the format and the
method of distribution so that the reader of the content has the best experience possible.
Imagine you’re planning your content marketing strategy. You want to distribute a white paper in PDF format
online, and invite your customers and prospects to open it on their mobile devices. Will it look the way you
want it to look? Will the images, colors, and fonts, you so carefully chose, continue to appear as expected to
represent your brand? Will it resize well?
And what if you want to send your PDF documents as email attachments or off er them for download from
your web site? Will they be too large for the user’s email server? What if your four-page marketing document
featuring color photographs, diagrams and charts, name and address fi elds, a few check boxes, and some
fancy fonts, tips the scale at 65 MB? How long before your prospect gives up during the download process?
According to MarketingSherpa, “Conversion Rates Correlated to Page Load Times (2014),” slow pages produce
lower conversion rates. In fact, a decline begins aft er waiting only 4 seconds. Th at’s how important it is to
ensure you’ve optimized your documents.
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Adobe PDF and eBook technologies for Developers
PDF document authoring tools adhere to the PDF specifi cation in varying degrees, and they are rarely
held accountable for the quality, usability or accessibility of the documents produced. Everyone, and by that, we
mean everyone with a computer, can create and display a PDF. Content managers rarely have control over the way
a PDF fi le gets created. Th is can result in too-large of a document, oft en not optimized for Fast Web Viewing. It
can be missing fonts, it can be just an image, or even a broken document that won’t meet the promise of a PDF,
i.e, to present document content reliably. PDF document consumption tools will account for and oft en repair
documents on the fl y, to the best of their ability. Other tools might just give up and leave the fi le unchanged. No
matter what, it is imperative for document consumption tools to have a high quality process in place to correct and
optimize PDF documents both for internal processes and external user distribution.
Th e PDF standard is 1100 pages long so it’s not a surprise that it takes a lot of expertise to craft a good PDF fi le. It
takes even more know-how to fi x a poorly craft ed one. Th e more advanced your set of PDF tools, the less you need
to worry.
Understanding Fonts in PDFs
When working with fonts, PDF documents are designed to be self-suffi cient. Th e best practice is to store the font
sets used for the text in a PDF document within the PDF document itself. In other words, font fi les are saved as
part of the larger PDF fi le. Th at way, when a user opens the fi le, that user’s computer system already has all of the
fonts it needs. Th e machine or device used to open and display a PDF document doesn’t have to go looking for a
set of characters stored on the local workstation or smartphone, and maybe guess at a reasonable replacement if the
right font fi le is not available. Th is practice is called font embedding and is an important part of the PDF format.
It guarantees that the text in a PDF document will always look the same no matter how or where it is displayed.
Embedding fonts is a great way to ensure consistency, but it comes at a cost. Font fi les can be quite large, especially
if the font includes Asian languages with vast character sets, like Mandarin or Japanese. You can make a PDF
document smaller and easier to share by removing these font sets. You need to make sure that the fonts used in the
PDF document are common, so that when a customer opens the fi le, the device the user is working with can fi nd
the fonts locally. Ideally, you want to embed only the font characters used in the document, creating smaller fi le
sizes while ensuring the proper characters are in place to represent the fi le as the author intended.
Color that Represents your Branding
Starting in the 1960s and 70s, computer and printing technology grew steadily more sophisticated. A wide range
of computing devices were introduced, by a wide variety of manufacturers, including workstations, monitors,
scanners, copy machines, printers, digital cameras, presses, many diff erent kinds of printers, and eventually,
laptops and mobile devices. How this hardware presents colors on screens or in print varies from one device to
another, because a device is designed to independently verify the colors it uses.
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Adobe PDF and eBook technologies for Developers
To create a uniform standard to govern how computer technology worked with colors, the International Color
Consortium (ICC) developed a color specifi cation in 1993 that was designed to work across all hardware and
soft ware platforms and for all operating systems. A variety of color profi les have been introduced, in the form of
.icc profi les, which are a mathematical description of a device’s color space and allow multiple devices to select the
appropriate colors to use when rendering content. A color management system (CMS) compares the color space
in which a color was created to the color space in which the same color will be output, then makes the necessary
adjustments to represent the color as consistently as possible among diff erent devices.
A color profi le can be stored on a hardware device to defi ne what a monitor can display or a printer print. Some
color models have a fi xed color space because they relate directly to the way humans perceive color. Other color
models, (RGB or CMYK) can have many diff erent color spaces. Because these models vary with each associated
color space or device, they are oft en described as being device-dependent. It’s important to remember that no
device is capable of reproducing the full range of colors viewable to the human eye. Each device operates within a
specifi c color space that produces an individual range, or gamut, of colors.
A color gamut
Reproducing color across diff erent mediums accurately is a diffi cult problem to solve. Color-matching problems
result from various devices and soft ware using diff erent color spaces. Because of these varying color spaces, colors
can shift in appearance as you transfer documents between diff erent devices. Color variations can result from
diff erences in image sources; the way soft ware applications defi ne color; print media, and other variations, such
as manufacturing diff erences in monitors or monitor age. Th is shift in colors represents a real problem when
documents are intended to represent your brand. Rendering the content for an individual device does not insure
that the content will be read on that device. Users can very easily read a PDF on an iPad, desktop computer, laptop,
and a phone. As a result, users creating content must utilize tools that have color management capabilities so that
your brand is accurately represented across platforms. Accurate color representation is particularly important
when it comes to presenting items that defi ne a business’s identity like company logos, for example.
RGB Color Gamut
CYMKColor Gamut
Visible Color Gamut
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Adobe PDF and eBook technologies for Developers
Balancing the Image Quality with Portability
When a PDF document includes images, such as diagrams or photographs, these images are embedded in the PDF
document as graphics fi les, such as JPG, TIF, and BMP fi les. If the original images are created with high resolution,
they will look good but be quite large, and as a result the PDF document where they are stored will be large, too.
To make a PDF document smaller, you can reduce the size of images in a PDF document by down-sampling them.
Th e down-sampling process reduces the resolution of an image, while protecting the integrity of the original colors
shown. When you down-sample, information is deleted from the image. Eff ectively the soft ware reduces the width
and height of images, in pixels. However, not all down-sampling results in high enough quality. Th ere is a real art
to creating fi les that are optimized for sharing while still representing the document and your brand accurately.
Compression and down-sampling can signifi cantly reduce the size of a PDF with little or no loss of detail and
precision. However, you will want to experiment with PDF options to fi nd an appropriate balance between fi le size
and image quality.
Transparencies
A transparency refers to objects on a page, such as images or text, which are transparent or ‘show through’ in some
way. Examples may include lightening part of an image so text shows through or showing parts of an object that
would be hidden under a layer. Transparencies are generally used to add complexity and richness to documents.
While providing great benefi ts, transparency is a complex technology to process. In fact, the Adobe technical
documentation on transparencies is over 100 pages long. Still, today’s document creators are regularly making
documents that contain transparent elements.
Processing transparencies can be tricky, and results can vary based on the tool. Th is can result in an inconsistent
message across your users. Generally, if you want to distribute a PDF document with transparencies to a broad
audience, it makes sense to fl atten transparencies fi rst. Th is process works just the way it sounds—the layered
transparencies are squeezed together and saved as a single permanent image that is embedded in the PDF
document. Flattening transparencies creates a stable standard version of the PDF document; the resulting fi le will
look the same regardless of the hardware or soft ware used to view it later. Th e process also tends to make the PDF
document larger, and it is a good idea to optimize the resulting images, once fl attened.
Note that other soft ware products used to view or work with PDF documents are oft en designed to automatically
fl atten any transparencies found in a PDF. All the more reason to fl atten transparencies in PDF documents
yourself, because this allows you to control the settings used.
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Adobe PDF and eBook technologies for Developers
PDF and the Intended Reading Space
Th e big issue to consider may simply be that PDFs are still diffi
cult to view on mobile devices. Each operating
system handles them diff erently, forcing users to download various apps to view the PDFs, making them hard to
consume. Readers are forced to do a lot of scrolling or pinching-and-expanding to read the document.
Th ese PDF obstacles make it less likely that mobile users will read your content. Since mobile content
consumption has surpassed desktop consumption, it’s important to prepare documents for the intended viewing
method and to optimize accordingly.
Managing PDF Documents using the Adobe Library and PDF Optimizer
When working with PDFs, you have to manage your documents with two things in mind: quality and fi le size.
You need to fi nd a way to reduce the size of this fi le so that you can make it easier to use, while making sure that
you don’t lose anything that might jeopardize your brand or the integrity of the original document. You want to
protect your reputation for quality; that’s not going to happen with a white paper that contains fuzzy drawings and
mismatched fonts, no matter how quickly the reader can open the document on a smart phone.
Th at’s why Datalogics off ers the Adobe PDF Library with PDF Optimizer. PDF Optimizer is an API that works
with the Adobe PDF Library to simplify the process of altering existing PDF fi les to increase compatibility with
user’s viewing environment, while making the fi les smaller. Essentially it automatically reduces the size of a PDF
document without compromising the quality of that document. With it, you can embed tools in your process that:
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Create a PDF fi le optimized for the targeted viewing method
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Reduce image resolution while maintaining image fi delity
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Convert color in a way that is ideal for the target medium
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Flatten transparencies to improve document portability
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Embed only the necessary subset of fonts to view the document
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Apply customized settings with the API toolkit
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Implement settings without the need for prior PDF experience
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Adobe PDF and eBook technologies for Developers
And with the Adobe Library and PDF Optimizer, you can be confi dent that your readers won’t notice any changes
in how a PDF document appears aft er you have reduced its fi le size. Th e colors remain true, the images still look
as good as ever when displayed, the fonts won’t change. Th is applies across Windows and Mac browsers, Apple
and Android mobile devices, Kindles or Nooks, or any of the variety of devices and platforms your customers are
likely to want to use. With the Adobe PDF Library and PDF Optimizer, you can repurpose your existing PDF
documents and the PDF workfl ow you already have in place to create PDF documents that are smaller and easier
to distribute.
Altona Test Suite
You may have considered switching from PDF to HTML or EPUB fi les for presenting a document to users with
mobile devices. But what if you already have in place a process that generates the PDF documents you need, and
that has worked just fi ne for nearly 10 years? Installing new soft ware, retraining your staff , and building new
batch processes to replace your PDF content with EPUB or HTML content could take a lot of time and money,
money you don’t need to spend. You have the PDF fi les you need. You just need to use the PDF Optimizer from
Datalogics to make these portable fi les more portable. If your goal is to create PDF documents that otherwise look
good and don’t change and that are small enough to distribute online, PDF Optimizer will solve this issue.
Adobe Acrobat provides a related function. If you open a PDF in Acrobat and select File and Save As, Other, and
then choose Optimized PDF, you can create a compressed version of the fi le. Th e feature in Acrobat off ers detailed
parameters that you can work with to adjust how the soft ware product manipulates your PDF document, and the
fi nal result can be dramatic. Acrobat is only practical if you are prepared to open and manually optimize each PDF
document one fi le at a time.
Original fi le size 11.6Mb
Optimized fi le size 2.44Mb
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Adobe PDF and eBook technologies for Developers
What if you have hundreds, or maybe thousands, of PDF documents
you need to work with? What if you are creating hundreds of new
PDF documents every day that need to be optimized? Th e advantage
of working with the Adobe Library with PDF Optimizer is that you
can use it as a basis for building your own code to optimize PDF
documents, and run that code from a server. You can embed the
optimizer code in another application or run it as a batch process
aft er business hours, automatically processing dozens or hundreds
of PDF documents overnight. With PDF Optimizer, you can easily
add a step to your existing PDF document workfl ow to optimize each
PDF document automatically as it is created, and with the settings
that make the most sense to you.
How PDF Optimizer Works
PDF Optimizer looks at every part of the PDF document for
elements that can be squeezed, or that don’t need to be there. First,
the utility downsamples, and/or compresses, images found in the
document. Th en it identifi es a variety of items that could be
considered optional. Th is would include some images and font fi les
stored within the PDF document itself, as well as other items such as
comments and other changes, metadata, color profi les, bookmarks,
thumbnails, labels, and dictionaries.
If what you really want to do is reduce the size of a PDF document so that a user can easily open and read it online,
there are a lot of items within a PDF document that you can do without. For example, some PDF documents store
multiple copies of images to use as alternates for printing or displaying on certain kinds of devices. Usually the
complete fonts that a PDF document needs are stored within the document itself, so that the system used to display
a PDF does not need to look for copies of the fonts on the device where the PDF is opened. You can also probably
do without bookmarks and some navigation tools. You can set up the Adobe Library with PDF Optimizer to
identify these sorts of objects within a PDF document and remove them, or you can use the default set of settings
provided.
Managing Images
You can set a target resolution for the images in a document, and the Adobe Library with PDF Optimizer
will reduce the resolution for each image found in that document to match this target. Or if a single image
appears multiple times in a PDF document, PDF Optimizer can select one example of that image and use it as
a benchmark. All of the other examples of that same image in the document would be reduced to match the
resolution of the image you selected.
Adobe Library with PDF Optimizer can also reduce the size of images in a document by compressing them using
a compression format like Flate or JPEG. Th e tool can even un-compress an image and then recompress it using a
diff erent compression method, if the new compression method is more eff ective in reducing fi le sizes. Finally, the
tool looks for and discards duplicate images embedded in a PDF document that are not needed. Sometimes a PDF
document holds alternate images, or multiple copies of a single image, so that one can be presented to a printer,
and another to a monitor.
What customers are saying
about Datalogics.
“Datalogics has provided superb help
with very short turnaround time that
enables us to resolve problems in our
products accurately and quickly.”
“I love using the Adobe PDF Library - we
were using a mish-mash of other tools
and this API makes our product so much
better.”
“I really enjoy working with the
team and appreciate the extra eff ort
that goes into the quick answers to
engineering questions.”
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Adobe PDF and eBook technologies for Developers
Removing Objects in the PDF Document
You can set up the Adobe Library with PDF Optimizer to remove a items from a PDF document to enhance
portability. If your goal is to make a PDF document as compact as you can, so that you can distribute it easily
online, and you know that the document will probably not be printed, you can let the tool eliminate objects
automatically. Th is includes:
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Bookmarks
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Page thumbnail images and labels
• Attached fi les
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Several kinds of internal dictionaries that aid navigating through the document or that are used for editing
and managing the PDF fi le
• Comments and metadata
Making Adobe PDF Library and PDF Optimizer Work for You
Datalogics provides a product that allows you to process dozens or hundreds of PDF documents at a time,
signifi cantly reducing the size of those documents without compromising their quality. With the Adobe PDF
Library and PDF Optimizer, you can take existing PDF documents and make them much easier to share. To
download a free evaluation of the Adobe Library with PDF Optimizer go to http://www.datalogics.com.
About Datalogics
Datalogics, Inc. is a PDF and eBook technology company, dedicated to providing the highest quality soft ware.
Based in Chicago, IL, we support hundreds of customers worldwide who are using our technology in diverse
applications. With over 50 years of industry experience, we provide unmatched support, enabling customers
to bring their products to market faster. Datalogics is on the PDF Association board, and is a member of W3C
Transitional Publishing Industry (TPI) and the Readium Foundation.
Managing Fonts
If you are using a standard font in a PDF document that is likely to be found on any machine, you can use the
Adobe Library with PDF Optimizer to remove font fi les saved within the document. Th e resulting PDF fi le can
be dramatically smaller, and the appearance won’t change when the fi le is opened. If an uncommon font is used,
the tool can automatically create a font subset containing only the necessary characters to open the document,
resulting in high compatibility and reduced fi le size.
Datalogics, Inc. | 101 N. Wacker Drive | Suite 1800 | Chicago, IL 60606 | USA
Datalogics and the Datalogics logo are registered trademarks of Datalogics Incorporated. Adobe and the Adobe logo are either
registered trademarks or trademarks of Adobe Systems Incorporated in the United States and/or other countries. All other
trademarks are the property of their respective owners.

©2017 Datalogics, Inc.
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Adobe PDF and eBook technologies for Developers
datalogics.com | sales@datalogics.com | 312.853.8200