variable data – Global Graphics Software blog

February 2, 2023February 23, 2023

Digital watermarking in print workflows – Part 2 – When to add a digital watermark

In this second post about digital watermarking in the print workflow, author Martin Bailey explains the stages when it’s possible to add a digital watermark.

Digital watermarking is an emerging technology, part of the latest step on the evolution of product identification. Global Graphics Software has partnered with Digimarc, a leader in digital watermarking and a member of our Partner Network, to explore this topic and future developments.

Adding a digital watermark during the design stage

In some workflows the designer may apply digital watermarks to a design by, for instance, using a plugin to an application such as Adobe Illustrator. This is equally appropriate for both steganography and an artwork masking layer, and gives the maximum opportunity for approval of the design with the digital watermark in place, and for any rework to the design that might be requested to realize the greatest benefit from using that watermark.
It will not normally be appropriate for the digital watermark to be added by the designer if each instance of the print requires unique data to be encoded in it; variable data composition is usually performed later in the workflow.

Application of digital watermarking has different advantages and disadvantages at various stages in the design and production workflow.

Adding a digital watermark in composition/prepress

In other workflows adding the digital watermark may be a function of a variable data composition or prepress department. Just as for application by the designer, this is applicable for both steganography and an artwork masking layer. There is a reasonable opportunity for approval of the design with the digital watermark in place. But it would be slower and more expensive to rework the design if that is required at this stage than if the watermark were added by the designer.

If the digital watermark is added in prepress then it can carry both static and variable data. As discussed above, however, variable data is best suited to use of an artwork masking layer rather than steganography, if only because of the amount of data that must be generated and then incorporated into a PDF file when steganography is used for a significant number of unique codes.

But applying even an artwork masking layer in prepress does bulk up the resulting print-ready PDF file with many copies of that layer, each one carrying different data. And it can also slow down processing in the Digital Front End (DFE) for a digital press. An overprinted graphic covering large areas of each piece of output in the PDF file can make it harder for the variable data optimization in a DFE to break the design apart so that it can minimize the total amount of processing required to read, color manage, render and halftone screen the job. (See Global Graphics Software’s guide: Full Speed Ahead: How to make variable data PDF files that won’t slow your digital press.)

Late-binding in the Digital Front End (DFE)

A new development in the application of digital watermarking is to add the marks right at the very last minute before the data is printed. In our SmartDFE™, for example, this can be done in parallel with or after the color management and rendering.

Applying the watermarks in parallel with color management and rendering (in the RIP) allows full access to all color channels for the output, while also removing the need to generate a fully resolved “optimized PDF” or PDF/VT file containing all of the variable data further upstream. In turn, this can reduce the overhead of optimizing variable data processing in the RIP. The final result is increased throughput, both in composition/prepress and in the DFE.

Applying marks after the RIP enables even higher performance through the DFE, with the added benefit of providing a more predictable processing speed because the amount of processing required is more deterministic than is rendering PDF. This might restrict the watermark to be painted in only one color channel, though.

Increasing speed and predictability in the DFE allows the use of lower cost hardware in those DFEs, or assists with printing at full engine speed for a larger proportion of jobs.

Late-binding application of digital watermarks will also always occur in an environment where the characteristics of the press that will be used to print the items are known, including resolution, bitdepth etc.

These benefits make this the optimum choice for highly efficient printing workflows for variable data digital watermarks, driving digital presses at full engine speed. The trade-offs are that it’s a little harder to review and approve proofs of the output, and that use for images with steganography is not usually appropriate.

This is an excerpt from the white paper: Optimizing Digital Watermarking in Print Workflows. To learn more about digital watermarking download your copy:

DOWNLOAD YOUR COPY OF THE WHITE PAPER

About the author

Martin Bailey, CTO, Global Graphics Software

Martin Bailey, former distinguished technologist at Global Graphics Software, is currently the primary UK expert to the ISO committees maintaining and developing PDF and PDF/VT. He is the author of Full Speed Ahead: how to make variable data PDF files that won’t slow your digital press, a guide offering advice to anyone with a stake in variable data printing including graphic designers, print buyers, composition developers and users.

Addressing real-world software challenges in the print industry

It’s always good to see our technology being used in the ‘real world’; it really helps us to understand our customers’ daily challenges so we can develop software to make their lives easier.

With this in mind, we recently visited Baker Labels, a leading UK trade label printer with over 45 years’ experience in the business. Bakers has three HP Indigo WS6900 presses, an HP Indigo 20000 press, a Truepress Jet L350 UV and L350 UV+LM inkjet press, as well as a Nilpeter FB3 flexographic press.

Managing director Justin Bailey reflects on our visit:

Global Graphics Software’s technology is used by many thousands of printing companies around the world. We’re committed to innovation and to continue to innovate it’s important that our software developers understand the challenges faced by those companies in the printing industry. I wanted to take our team to an environment where the code they have written might be used.

I set out to find a printing company that shared our values in innovation and would be happy to show us around their facilities. My research led me to Baker Labels, a leading UK print provider for the label and packaging market, who embraced the idea of welcoming us and showing us round.

The thing that struck me immediately about Bakers, was the pride they had in their business and the culture they had built, which clearly radiated as soon as you walked through the door. It was also a bonus to learn that they use PACKZ® and CLOUDFLOW® from our sister company, HYBRID Software, to automate many of their processes.

Bakers also work very closely with HP Indigo in both their label printing business, and BakPac, their flexible packaging business. This meant that our Harlequin RIP® engineers could see presses working that used the technology they had developed deep inside the HP Indigo digital front end. This gave them a sense of real purpose and pride.

HP Indigo 6900 at Baker Labels — One of the HP Indigo 20000 presses at Baker Labels.

Baker’s BakPac digital flexible packaging business prints short to medium runs of stand-up pouches, pillow pouches and printed film for trade customers looking for a high-speed-to-market option for their customers.

Bakers’ domain expertise was clear for our team to see: Jamie Godson did an incredible job of explaining the application of technology and challenges that they face within the industry; Jamie Doogan provided important perspective on commercial considerations; and Simon Chandler shared his perspectives on technical infrastructure necessary to stay competitive in the market.

Feedback from my team was overwhelmingly positive and the energy that they got from the visit will be something that I am confident will continue to resonate within our engineering team, spurring on new ideas to solve challenging technical problems. Bakers’ willingness to engage in such conversations will no doubt help us all to do what we do better and facilitate solutions which may well have a broader market application.

On behalf of the Global Graphics Software and Hybrid Software Group PLC, I would like to express my gratitude to Steve Baker and his team for their incredible hospitality and willingness to collaborate. It’s meeting people at companies like Bakers that makes getting out of bed in the morning exciting, and it’s no surprise to me that they are as successful as they are. Long may it continue.

Managing director, Justin Bailey, left, with the team from Global Graphics Software and Jamie Godson, Jamie Doogan and Simon Chandler from Baker Labels.

Justin Bailey, Managing Director, Global Graphics Software

Justin Bailey has been managing director at Global Graphics Software since 2018. He has over 25 years’ experience in the document imaging and print markets.

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August 1, 2022August 11, 2022

Unlocking the Holy Grail: the key to mass customization at mass-production prices

Mass-personalized or -customized products at near mass-production prices is a huge potential area for growth for digital print. Only with digital can you print in real time onto anything and everything, such as 3D objects, clothing, flooring, tiles and wallcoverings, to give a unique customized product.

In this post, Martin Bailey, former CTO and now consultant at Global Graphics Software, explores the rise of the use of variable data and how digital inkjet is the key to unlocking the Holy Grail for many retailers: mass customization at near mass-production prices.

It’s common to think of variable data printing, where at least some of every instance is different from every other instance, as being the preserve of transactional and direct mail printing. Admittedly, that’s where much of it started, but in the broadest sense of the term, variable data printing is now used far more widely, across multiple industries. In situations where the delivery of the product is through a push model (where there is no direct connection between each item produced and a specific recipient at the time of production) several cases are common. Most of these cases are in B2B environments, where the buyer then sells or delivers the result, often B2C.

In mainstream commercial print, labels, packaging and industrial manufacturing, it’s difficult to imagine an alternative to the push model, even given the huge amount of metadata that some companies, such as luxury goods brands and supermarkets, are collecting on their customers.

But there are many situations where there’s a much closer relationship between an end user of the product and the organization that printed or manufactured it, which can be described as a pull model instead. Many of these cases move beyond the traditional idea of variable data as being text and barcodes imaged on top of a static background to each piece being truly unique. They deserve to be described as mass customization, and all of them have been enabled by web-to-print or other forms of online ordering.

The wide format market has long provided display and soft signage, sportswear, tee shirts and car wraps to custom designs on very short runs, down to a single copy. Both signage and sportswear are aimed at both B2B and B2C markets.

Photofinishing has long been a B2C business and has used digital printing for decades. The industry has learned that simply producing 5” x 7” prints does not generate significant profits, but has grown first into photobooks, and then into many other forms of product decoration, printing photographs on hats, shoes, apparel, bed linen, mugs etc and converging with what have historically been wide format opportunities. Each individual order, perhaps for one mug with a photo printed on it, may not appear to be variable data printing. But when orders are aggregated at the producer there may be hundreds or thousands of mugs to be printed per day, each with a different image.

Photobooks offer higher margins than simple print finishing.

The same business model is applied more broadly to print designs which may be uploaded by the customer and/or created in a web portal by combining the customer’s text and graphics from a library. Examples include phone cases, tee shirts, postcards and greetings cards.

And a number of providers effectively act as publishers for customer designs, managing printing and fulfilment for a variety of products or lengths of custom-printed textile. Examples include Red Bubble and Spoonflower.

Several brands have run campaigns whereby products can be ordered with a name on them, usually for gifting. Examples include “My Nutella” and “My Marmite”. A variant of this is where only a label is purchased, often for bottles of spirits, to be applied to the product by the purchaser themselves.

The most famous campaign for ‘personalized’ labels was Coca-Cola’s “Share a Coke”, but in practice most labels were printed in long runs, randomizing the most common names in each country; only labels from roadshows and purchases from the web were actually printed on demand for specific recipients. This makes it an excellent example of a hybrid model taking advantage of the benefits of multiple print technologies.

Personalized Marmite jars - personalized product for gifting can attract a significant premium — Personalized product for gifting can attract a significant premium.¹

Even in industries producing a design that would historically have been created in multiple mile or kilometer lengths, such as wallcoverings, there are opportunities for increased margins in custom delivery. As an example, consider a decorating company that has been contracted to apply wallcoverings to a large office. If a wallcovering vendor could deliver pre-cut drops of the wallcovering, each of exactly the right length, and with the pattern starting in exactly the right place so that each drop aligns with those on either side, that would save the decorating company a lot of time. And that, in turn, would allow the vendor to charge a sufficient premium to more than cover the reduced total length required because there is no longer any wastage from the decorators cutting each drop to ensure alignment.

A lot of the demand for this mass customization is ascribed to the changing attitudes and communication preferences of millennials and Gen-Z. To generalize, it’s often said that such audiences demand to be treated, and be able to represent themselves as unique, requiring them to be able to obtain unique product in support of that position.

But the demand is not specific to any age group, according to “The Deloitte Consumer Review – Made-to-order: The rise of mass personalization”, based on survey results from YouGov, which also went on to say: “1 in 5 consumers who expressed an interest in personalized products or services are willing to pay a 20% premium”; that figure rises to around 1 in 2 for customized clothing, furniture, homeware and DIY.

Demand for customized product is not restricted to any particular age group.

Of course, personalized and customized products are not warehoused at all; they’ve been created for a specific recipient and will usually be shipped immediately.

Inkjet can achieve unique results

Taking short runs to the extreme, a significant advantage for inkjet that applies across the majority of industries is that it does not need to simply reproduce the same invariant design repeatedly, even for a short run; instead, it can make every item different.

Inkjet can achieve unique results in a variety of different industries and being unique in a useful way is a very effective lever for premium pricing and increased profitability.

This is an excerpt from the white paper: Software considerations for inkjet in the smart factory

DOWNLOAD YOUR COPY OF THE WHITE PAPER

Further reading:

What you need to build a press that must handle variable data jobs at high speed

Watch the video: Connecting print to a Smart Factory:

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¹https://www.marmite.co.uk/products/shop/marmite-personalised-classic-jar.html

November 11, 2021

What you need to build a press that must handle variable data jobs at high speed

I’ve spoken to a lot of people about variable data printing and about what that means when a vendor builds a press or printing unit that must be able to handle variable data jobs at high speed. Over the years I’ve mentally defined several categories that such people fall into, based on the first question they ask:

“Variable data; what’s that?”
“Why should I care about variable data, nobody uses that in my industry?”
“I’ve heard of variable data and I think I need it, but what does that actually mean?”
“How do I turn on variable data optimization in Harlequin?”

If you’re in the first two categories, I recommend that you read through the introductory chapters of our guide: “Full Speed Ahead: how to make variable data PDF files that won’t slow your digital press”, available on our website.

And yes, unless you’re in a very specialised industry, people probably are using variable data. As an example, five years ago pundits in the label printing industry were saying that nobody was using variable data on those. Now it’s a rapidly growing area as brands realize how useful it can be and as the convergence of coding and marking with primary consumer graphics continues. If you’re a vendor designing and building a digital press your users will expect you to support variable data when you bring it to market; don’t get stuck with a DFE (digital front end) that can’t drive your shiny new press at engine speed when they try to print a variable job.

If you’re in category 3 then you’re in luck, we’ve just published a video to explain how variable data jobs are typically put together, and then how the DFE for a digital press deconstructs the pages again in order to optimize processing speed. It also talks about why that’s so important, especially as presses get faster every year. Watch it here:

And if you’re in category 4, drop us a line at info@globalgraphics.com, or, if you’re already a Harlequin OEM partner, our support team are ready and waiting for your questions.

Speed and Scalability: two things to consider when choosing a RIP for your digital inkjet press

If you’re building a digital press, or a digital front end (DFE) to drive a digital press, you want it to be as efficient and cost-effective as possible. As the trend towards printing short runs and personalization grows, especially in combination with increasing resolutions, more colorants and faster presses, the speed and scalability of the raster image processor (RIP) inside that DFE are key factors in determining profitability.

For your digital press to print at speed you’ll need to understand the amount of data that it requires, i.e. its data rate. In this film, Martin Bailey, distinguished technologist at Global Graphics Software, explains how different stages in data handling will need different data rates and how to integrate the appropriate number of RIP cores to generate that much data without inflating the bill of materials and DFE hardware.

Martin also explains that your next press may have a much higher data rate requirement than your current one.

For more information about the Harlequin Core visit: www.globalgraphics.com/harlequin

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February 10, 2021February 3, 2021

Second edition now available: Full Speed Ahead: How to make variable data PDF files that won’t slow your digital press

At the beginning of 2020, in what we thought was the run-up to drupa, Global Graphics published a new guide called “Full Speed Ahead: How to make variable data PDF files that won’t slow your digital press”. It was designed to complement the recommendations available for how to maximize sales from direct mail campaigns, with technical recommendations as to how you can make sure that you don’t make a PDF file for a variable data job that will bring a digital press to its knees. It also carried those lessons into additional print sectors that are rapidly adopting variable data, such as labels, packaging, product decoration and industrial print, with hints around using variable data in unusual ways for premium jobs at premium margins.

Well, as they say, a lot has happened since then.

And some of that has been positive. At the end of 2020 several new International Standards were published, including a “dated revision” (a 2^nd edition) of the PDF 2.0 standard, a new standard for submission of PDF files for production printing: PDF/X-6, and a new standard for submission of variable data PDF files for printing: PDF/VT-3.

We’ve therefore updated Full Speed Ahead to cover the new standards. And at the same time we’ve taken the opportunity to extend and clarify some of the rest of the text in response to feedback on the first edition.

So now you can keep up to date, just by downloading the new edition!

DOWNLOAD THE GUIDE

There really are two different kinds of variable data submission!

There are two completely different forms of variable data handling in the Harlequin RIP®, and I’m sometimes asked why we’ve duplicated functionality like that. The simple answer is that it’s not duplication; they each address very different use cases.

But those use cases are not, as many people then expect, “white paper workflows” vs imprinting, i.e. whether the whole design including both re-used and single-use elements is printed together vs adding variable data on top of a pre-printed substrate. Both Harlequin VariData™ and the “Dynamic overlays” that we added in Harlequin version 12 can address both of those requirements.

Incidentally, I put “white paper workflows” in quotes because that’s what it’s called in the transactional and direct mail spaces … but very similar approaches are used for variable data printing in other sectors, which may not be printing on anything even vaguely resembling paper!

The two use cases revolve around who has the data, when they have it, whether a job should start printing before all the data is available, and whether there are any requirements to restrict access to the data.

When most people in the transactional, direct mail or graphic arts print sectors think about variable data it tends to be in the form of a fully resolved document representing all of the many variations of one of a collection of pages, combining one or more static ‘backgrounds’ with single-use variable data elements, and maybe some re-used elements from which one is selected for each recipient. In other words, each page in the PDF file is meant to be printed as-is, and will be suitable for a single copy. That whole, fully resolved file is then sent to the press. It may be sent from one division of the printing company to the press room, or even from some other company entirely. The same approach is used for some VDP jobs in labels, folding carton, corrugated, signage and some industrial sectors.

This is the model for which optimized PostScript, and then optimized PDF, PDF/VT (and AFP) were designed. It’s a robust workflow that allows for significant amounts of proofing and process control at multiple stages. And it also allows very rich graphical variability. It’s the workflow for which Harlequin VariData was designed, to maximize the throughput of variable data files through the Digital Front End (DFE) and onto the press.

But in some cases the variable data is not available when the job starts printing. Indeed, the print ‘job’ may run for months in situations such as packaging lines or ID card printing. That can be managed by simply sending a whole series of optimized PDF files, each one representing a few thousand or a couple of million instances of the job to be printed. But in some cases that’s simply not convenient or efficient enough.

In other workflows the data to be printed must be selected based on the item to be printed on, and that’s only known at the very last minute … or second … before the item is printed. A rather extreme example of this is in printing ID cards. In some workflows a chip or magnetic strip is programmed first. When the card is to be printed it’s obviously important that the printed information matches the data on the chip or magnetic strip, so the printing unit reads the data from one of those, uses that to select the data to be printed, and prints it … sometimes all in less than a second. In this case you could use a fully resolved optimized PDF file and select the appropriate page from it based on identifying the next product to be printed on; I know there are companies doing exactly that. But it gets cumbersome when the selection time is very short and the number of items to be printed is very large. And you also need to have all of the data available up-front, so a more dynamic solution is better.

In other cases there is a need to ensure that the data to be printed is held completely securely, which usually leads to a demand that there is never a complete set of that data in a standard file format outside of the DFE for the printer itself. ID cards are an example of this use case as well.

Moving away from very quick or secure responses, we’ve been observing an interesting trend in the labels and packaging market as digital presses are used more widely. Printing the graphics of the design itself and adding the kind of data that’s historically been applied using coding and marking are converging. Information like serial numbers, batch numbers, competition QR Codes, even sell & use by dates are being printed at the same time as the main graphics. Add in the growing demands for traceability, for less of a need for warehousing and for more print on demand of a larger number of different versions, and there can be some real benefits in moving all of the print process quite close to the bottling/filling/labelling lines. But it doesn’t make sense to make a million page PDF file just so you can change the batch number every 42 cartons because that’s what fits on a pallet.

These use cases are why we added Dynamic overlays to Harlequin. Locations on the output where marks should be added are specified, along with the type of mark (text, barcodes and images are the most commonly used). For most marks a data source must be specified; by default we support reading from CSV files or automated counters, but an interface to a database can easily be added for specific integrations. And, of course, formatting information such as font, color, barcode symbology etc must be provided.

The ‘overlay’ in “Dynamic overlays” gives away one of the limitations of this approach, in that the variable data added using it must be on top of all the static data. But we normally recommend that you do that for fully resolved VDP submissions using something like optimized PDF anyway because it makes processing much more efficient; there aren’t that many situations where the desired visual appearance requires variable graphics behind static ones. It’s also much less of a constraint that you’d have with imprinting, where you can only knock objects like white text out of a colored fill in the static background if you are using a white ink!

For what it’s worth, Dynamic overlays also work well for imprinting or for cases where you need to print graphics of middling complexity at high quality but where there are no static graphics at all (existing coding & marking systems can handle simple graphics at low to medium quality very well). In other words, there’s no need to have a background to print the variable data as a foreground over.

So now you know why we’ve doubled up on variable data functionality!

What’s the best effective photographic image resolution for your variable data print jobs?

It goes without saying that the final quality of your printed piece is paramount. But when speed and time constraints are also critical, what can you do to ensure your files fly through the press and still reward you with the quality you expect? Optimizing the images in the piece is a good place to start, but if you’re creating a job with variable data, where there are thousands of pages to print, each with a different image, how do you know what a sensible effective resolution is for those images that will ensure your PDF file doesn’t trip up the print production workflow?

In his latest guide, Full Speed Ahead, how to make variable data PDF files that won’t slow your digital press, Martin Bailey, CTO at Global Graphics Software, advises not to ask the print workflow to do more work than necessary if that doesn’t change the look of the printed result. Images are commonly re-used within a VDP job, so being able to process each image only once and then re-use the result many times can significantly increase the throughput of the digital front end. On the other hand, some images are personal to every recipient and must therefore be processed for every single recipient, slowing the workflow down.

Martin offers the following tips for setting appropriate effective photographic image resolutions:

Aim for 300 ppi, however the most appropriate image resolution for digital presses varies, depending on printing heads, media and screening used.
Bear in mind image content; soft and dreamy images can be sometimes placed at a lower resolution.
Don’t use a higher effective image resolution for photographic images than the output resolution as this is often not productive. The example in Fig 1 below illustrates how easy it is to use an image at several times the required resolution:

Fig 1: The same 12-megapixel (4000 x 3000 px) image placed on the page at three different sizes. Source: Full Speed Ahead, how to make variable data PDF files that won’t slow your digital press.

When an image is placed onto a page the original resolution of that image is largely irrelevant; what matters is how many pixels there are per inch on the final printed page. As an example, if you have a photograph from a 12 MP compact camera it’ll probably be approximately 3000 pixels by 4000 pixels. If that’s placed on the page as 3 inches by 4 inches (7.5 x 10cm) the effective resolution is about 1000ppi (4000/4). That would usually be about three times as much as you need in each dimension.

A variety of tools are available for optimizing image resolution, and some composition tools can also do this automatically. To find out more about the best effective resolution for your images, and to pick up more tips for optimizing your images for variable data printing, download the guide:

Full Speed Ahead – how to make variable data PDF files that won’t slow your digital press.

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June 16, 2020July 12, 2022

Why does optimization of VDP jobs matter?

Would you fill your brand-new Ferrari with cheap and inferior fuel? It’s a question posed by Martin Bailey in his new guide: ‘Full Speed Ahead – how to make variable data PDF files that won’t slow your digital press’. It’s an analogy he uses to explain the importance of putting well-constructed PDF files through your DFE so that they don’t disrupt the printing process and the DFE runs as efficiently as possible.

Here are Martin’s recommendations to help you avoid making jobs that delay the printing process, so you can be assured that you’ll meet your print deadline reliably and achieve your printing goals effectively:

If you’re printing work that doesn’t make use of variable data on a digital press, you’re probably producing short runs. If you weren’t, you’d be more likely to choose an offset or flexo press instead. But “short runs” very rarely means a single copy.

Let’s assume that you’re printing, for example, 50 copies of a series of booklets, or of an imposed form of labels. In this case the DFE on your digital press only needs to RIP each PDF page once.

To continue the example, let’s assume that you’re printing on a press that can produce 100 pages per minute (or the equivalent area for labels etc.). If all your jobs are 50 copies long, you therefore need to RIP jobs at only two pages per minute (100ppm/50 copies). Once a job is fully RIPped and the copies are running on press you have plenty of time to get the next job prepared before the current one clears the press.

But VDP jobs place additional demands on the processing power available in a DFE because most pages are different to every other page and must therefore each be RIPped separately. If you’re printing at 100 pages per minute the DFE must RIP at 100 pages per minute; fifty times faster than it needed to process for fifty copies of a static job.

Each minor inefficiency in a VDP job will often only add between a few milliseconds and a second or two to the processing of each page, but those times need to be multiplied up by the number of pages in the job. An individual delay of half a second on every page of a 10,000-page job adds up to around an hour and a half for the whole job. For a really big job of a million pages it only takes an extra tenth of a second per page to add 24 hours to the total processing time.

If you’re printing at 120ppm the DFE must process each page in an average of half a second or less to keep up with the press. The fastest continuous feed inkjet presses at the time of writing are capable of printing an area equivalent to over 13,000 pages per minute, which means each page must be processed in just over 4ms. It doesn’t take much of a slow-down to start impacting throughput.

If you’re involved in this kind of calculation you may find the digital press data rate calculator useful: Download the data rate calculator

Global Graphics Software’s digital press data rate calculator.

This extra load has led DFE builders to develop a variety of optimizations. Most of these work by reducing the amount of data that must be RIPped. But even with those optimizations a complex VDP job typically requires significantly more processing power than a ‘static’ job where every copy is the same.

The amount of processing required to prepare a PDF file for print in a DFE can vary hugely without affecting the visual appearance of the printed result, depending on how it is constructed.

Poorly constructed PDF files can therefore impact a print service provider in one or both of two ways:

Output is not achieved at engine speed, reducing return on investment (ROI) because fewer jobs can be produced per shift. In extreme cases when printing on a continuous feed (web-fed) press a failure to deliver rasters for printing fast enough can also lead to media wastage and may confuse in-line or near-line finishing.
In order to compensate for jobs that take longer to process in the DFE, press vendors often provide more hardware to expand the processing capability, increasing the bill of materials, and therefore the capital cost of the DFE.

Once the press is installed and running the production manager will usually calculate and tune their understanding of how many jobs of what type can be printed in a shift. Customer services representatives work to ensure that customer expectations are set appropriately, and the company falls into a regular pattern. Most jobs are quoted on an acceptable turn-round time and delivered on schedule.

Depending on how many presses the print site has, and how they are connected to one or more DFEs this may lead to a press sitting idle, waiting for pages to print. It may also delay other jobs in the queue or mean that they must be moved to a different press. Moving jobs at the last minute may not be easy if the presses available are not identical. Different presses may require different print streams or imposition and there may be limitations on stock availability, etc.

Many jobs have tight deadlines on delivery schedules; they may need to be ready for a specific time, with penalties for late delivery, or the potential for reduced return for the marketing department behind a direct mail campaign. Brand owners may be ordering labels or cartons on a just in time (JIT) plan, and there may be consequences for late delivery ranging from an annoyed customer to penalty clauses being invoked.

Those problems for the print service provider percolate upstream to brand owners and other groups commissioning digital print. Producing an inefficiently constructed PDF file will increase the risk that your job will not be delivered by the expected time.

You shouldn’t take these recommendations as suggesting that the DFE on any press is inadequate. Think of it as the equivalent of a suggestion that you should not fill your brand-new Ferrari with cheap and inferior fuel!

The above is an excerpt from Full Speed Ahead: how to make variable data PDF files that won’t slow your digital press. The guide is designed to help you avoid making jobs that disrupt and delay the printing process, increasing the probability of everyone involved in delivering the printed piece; hitting their deadlines reliably and achieving their goals effectively.

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Martin Bailey first joined what has now become Global Graphics Software in the early nineties, and has worked in customer support, development and product management for the Harlequin RIP as well as becoming the company’s Chief Technology Officer. During that time he’s also been actively involved in a number of print-related standards activities, including chairing CIP4, CGATS and the ISO PDF/X committee. He’s currently the primary UK expert to the ISO committees maintaining and developing PDF and PDF/VT.

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February 3, 2016November 21, 2019

PDF/VT – bringing all the advantages of PDF workflow to the world of variable data printing

Martin Bailey, consultant and former 0CTO, Global Graphics Software

Standards for variable data printing (VDP) have come a long way since the first work by CGATS to develop a universal delivery format in the late 1990s. In 2010 the International Standards Organization published the PDF/VT standard, marking the first really effective specification for a reliable, vendor-neutral exchange of variable data jobs, both within and between companies.

A special type of the PDF file format, PDF/VT is specifically used for variable data and transactional printing in a variety of environments, from desktop printing to high volume digital production presses. Built on PDF/X, it therefore brings all the advantages of that standard in enforcing best practices for reproducible and predictable color and appearance to the variable data and transactional print worlds.

The industry is gradually realizing its value to improve quality, competitiveness and productivity, and I’ve been working with the PDF/VT Competence Center, especially with Christoph Oeters (Sofha), Paul Jones (Teclyn bv) and Tim Donahue (technical consultant) to produce a new set of Application Notes highlighting the benefits of using PDF/VT and the workflows that it enables.

The Application Notes explain how to make the highest quality and most efficient PDF/VT files to achieve the required visual appearance of a job, so if you develop software to read and write PDF/VT files, for example in composition tools, RIPs, digital front ends and imposition tools, or if you work on print workflow integration, you’ll find the notes really beneficial. They also show how document part metadata can be applied and leveraged for VDP specific production workflows.

Of course, there are wider benefits to using PDF/VT: The adoption of PDF/VT will allow the industry to finally move towards a reliable, vendor-neutral exchange of variable data jobs, simplifying the process of variable data printing significantly.

The application notes are free to download, pick up your copy here: http://www.pdfa.org/publication/pdfvt-application-notes/.

Let me know what you think of them – feedback is always welcome.

Additional reading:

Do PDF/VT right by Global Graphics Software

PDF/VT for personalized print by the PDF/A Competence Center

Read the press release from the PDF Association (http://www.pdfa.org/2016/01/pdf-association-publishes-pdfvt-application-notes-showcasing-the-benefits-for-variable-data-print-streams/)