Quality Assurance: Find the Differences!
Since we were young we all have enjoyed since we were young the game of looking at two pictures and trying to find where the differences. We can’t help ourselves; we start looking to see if we can find the total number, or what others see.
Now take that same game and place it into corporate environment where every unexpected difference can cost your company time, money, customers and your reputation. What if all of a sudden its not one image but countless forms floating around a company when the address changes? What if there's a change in the executive board or the company designs a new logo? The forms usually end up in the shredder – along with a small fortune in dollars. Especially in large firms, the value of what was once an asset can quickly climb into the tens of thousands.
Anyone who deals with mailing and printing knows: even the tiniest changes in the format can impact the layout of an entire document, whether it's a new font, a new logo, or just one extra hyphen in the company or product name. Documents are often updated using design software. The problem with that is not knowing how the changes will ultimately affect the quality of the printed page. An even more important question is whether the different versions of a document, e.g. created to reflect a software update, are identical in terms of content and layout. This is no simple task, since the check has to be run at the bit level – something that conventional composition tools just don't do.
Document comparison in the production environment is nonetheless essential to reliably ensure the necessary quality in the document creation and output. Different suppliers in the world of output management have therefore specialized in developing check programs to automatically compare documents and data streams. The software solutions list the differences found in log files, as well as displaying them graphically on the screen.
The digital light table
For a visual comparison, each document is converted into a pixel image of equal resolution and the resulting raster images compared, as if on a light table. The two documents are then overlaid to reveal the differences between them since the software presents the area where the two versions deviate. Users are thus able to make the necessary changes exactly where needed.
The principle: the software reads in two files, e.g. in AFP, PDF or PostScript, Metacode compares the original to the modified version and displays the differences found in just seconds. Comparisons at the pixel level identify the changes and their location. Comparisons at the structural level evaluate character sequences of the text, font attributes and other properties that affect the output. The benefit is obvious. Production problems due to unintentional changes to the mailing are avoided. Reprints always mean reworking costs and damage the credibility of the print center with its customers.
What Really Changed?
The following illustrates just how hot this topic has become. A well-known direct mail provider generates 1,200 different documents a month, usually relatively simple, double-sided, personalized letters and correspondence. In the coming years, the company is expecting up to 5,000 different versions per month. Yet they are already struggling to reliably handle the current number while demand for personalized documents is growing. Hardly anyone in this situation would be in a position to manually check differing versions for the needed matches and permissible deviations (including date, address field).
Until recently the mailing provider used a Web-based online program for employees to check and keep track of the different versions, what happened to them and what was produced. But comparing an old and a new version was anything but simple. They had to print out the original document and then hold it up to the screen to compare it to the new – a rather tedious affair just to find out what had changed. Modern check programs like DocBridge Delta digitize and automate these comparisons. The differences are combined in a "third" comparison document and are available to users for evaluating the print job for the customer. The advantage: the graphical display of the deviations makes for quick decision-making.
Imagine a letter that looks okay, but the "overflow" from the address field is threatening to push the rest of the content downward. A graphical comparison shows the layout problems and isolates the area where the content is impacted by the changes. This makes it quick and easy to determine whether the text is the same, the breaks can be matched and whether the text is shown in the same font.
A Hyphen Can Change Everything
These tools also uncover technical differences in various software versions quickly and easily. Regression tests are critical to prevent the unwanted outcomes associated with such changes to the system software. An update, for example, may have changed the default setting for hyphenation or punctuation differences may have emerged in the address fields. One version uses periods after abbreviations the other does not. Punctuation might not seem all that important to an outsider, but it is a quality criterion in the creation of individual documents.
In the final analysis, what's important is delivering exactly what the customer asked for. Especially in companies with many different print jobs and frequent software changes, quality assurance is therefore a focal point.
- Obsoletes most of the tedious, high manual effort of document QA
- Ensures that all documents from any source meet the consistent high quality standards of your organization
- Near instantaneous productivity after installation
- Faster process captures lost time with better productivity and better results
- Interface is usable by all rolls and responsibilities in output/document management
- Web-based, behind the firewall installation makes it accessible and easy to maintain