2022.2

generates, if that page contains a pattern. PReS Workflow also stores a copy of each document in the
Capture Database, in PDF format.
While a document is printed, and while this printed document has not received any ink or signature, the
document is deemed "open", the pattern it uses remains locked in the database and cannot be re-used.
Then, when someone writes on the document and sends the pen data to PReS Workflow (through a
docking station or through Bluetooth), if the required conditions have been met, the document will be
"closed", its pattern released and available to be used immediately.
An open document can also be called a "live" document, in the sense that it is only active between the
time where it is printed and the time where ink from the Anoto Digital Pen is processed and the doc-
ument is closed. This duration is called "time to live" or "TTL", and it is the second very important num-
ber: how long is the pattern actually needed.
The third important number is based on your actual output needs. In other words, how many documents
do you intend to print on a regular basis that will contain a pattern?
These three numbers, together, represent an easy way to determine if the 20,000 patterns are actually
enough for you. Basically, if you generate X documents within a specific time frame but N of these doc-
uments are closed through regular process (writing on them with a pen and docking it) during that
period, does the difference between both ever reach 20,000?
Example
Say you print 19,000 pages containing a pattern, every day. You may think you'll "run out of patterns"
after a single day. But if 18,900 of these documents are being written to and processed within the day,
at the end of the day you only have a 100 page difference, possibly due to mistakes, lost pages, or
errors during processing. In this specific example, you would run out of patterns only after 10 days,
assuming the numbers remained completely static. Since there are easy ways to deal with these
remainders (a simple automated process that, once a day, closes any document that is older than 48
hours, for example), a correct implementation like this one would be perfectly functional and not be
affected by the 20,000 page limit. Remember however that this means that 19,000 physical sheets of
paper are printed every day, and those 19,000 documents are written on using one or more Anoto
Digital Pens, which are then processed back into the system.
The example above actually uses numbers that are much higher than our typical PlanetPress Capture
user. That is to say, a vast majority of our users will never have to worry about reaching the pattern lim-
itation, unless their implementation is missing important parts, such as the "cleanup" process. But this
also means a smaller minority of our users may require more than 20,000 patterns, so let's deal with
this now.
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