[PDFdev] PDF files optimized for RIPping

[Cynthia Leslie]

The term "optimized PDF file" has been bandied about for a couple of years in connection with printer/RIP performance. When people use this term in the context that I am focusing on here, they are referring to a PDF file that is constructed such that information that is common to all the pages is stored only once and referenced as needed. These kinds of PDF files are typically talked about in connection with variable-data-printing/publishing applications, which usually output a PDF file that contains a collection of documents that are similar but not identical.   The idea is that if such a PDF file is sent to a printer/RIP that is designed to take advantage of the optimization, documents will print at or near rated print speed whereas they would print relatively slowly if the PDF file was not optimized (i.e., if it contained a lot of redundant information).   One such optimizated PDF format is the PPML/VDX format, but I am NOT talking about that format, because (as far as I know) the only PPML/VDX-consuming device available today is the NexPress -- and I'm interested in an optimized PDF format that is designed for many RIPS/printers -- ideally, B&W devices and well as color devices.   Note also that I am NOT talking about the linearized PDF format, which is optimized for Web viewing and is documented in Adobe's PDF Reference.   What I am talking about is some other PDF format or formats that are generated by various software applications, typically variable-data-printing/publishing applications.   My first question is this: when people talk about an optimized PDF file in this context, are they referring to a particular format that is documented somewhere? I have not been able to find any standard or specification for this.   Also: I know that the kind of optimized PDF files that I'm talking about will only print at or near rated print speed on certain printers/RIPS that are designed to take advantage of such optimization. So my next question is: what printers/RIP are designed to take advantage of this kind of PDF optimization? Or, is it a matter of proprietary formats -- i.e., does an application have to generate a particular type of optimized PDF format for one printer/RIP, a different kind of optimized PDF format for another printer/RIP, etc.?   BTW, I realize, of course, that there are lots of non-PDF print-stream formats that are designed to make certain printers/RIPS print as fast as possible (e.g., VPS, VIPP, FreeForm, etc.) -- but we have reasons for wanting to stick with a pure PDF workflow for a particular application that we are working on.   Any and all replies and comments are welcome!   - Cynthia Leslie