rivviepop phantom :: knowledge in passing

You have a PDF. You have the official Adobe PDF Viewer already installed on your handset. Yet, trying to view the PDF results in an “out of memory” message. “But I’ve got 65meg free” you say, “why doesn’t it work?”

The problem is that the PDF is too large uncompressed to fit in RAM (which is usually around 10mb free — don’t confuse operating ram with storage memory). That 65meg you see is storage memory within the handset, not actually the type of memory it can use to run applications.

The typical Nokia S60v3 device currently on the market has about 20mb of operating ram, some with more and some with less. Steve Litchfield (prolific AllAboutSymbian author) maintains a S60 Device History where you can look up your handset:

http://3lib.ukonline.co.uk/s60history.htm

After booting, you may have on average 10-13mb of ram free, depending on what startup apps you have installed. This amount is basically what you have left to run the PDF Viewer and view the uncompressed PDF file; as you can see, it’s not that much. Understand that a PDF that shows as 1mb on disk can use 30 times as much ram, maybe even more – it’s in a compressed format, and may contain a lot of drawing complexity.

For instance, there’s a PDF I desperately want to view on my device, it’s the SF Muni transit routes:

http://transit.511.org/providers/maps/SF_928200510805.pdf

Note that the file is only 1.1meg physically on disk. However, when I use XPDF (a trustworthy PDF viewer for X11) and gauge the memory it needs to render the document at 100% resolution, it’s about 36megs of ram (not a scientific benchmark, just using top). So, the handset does not have enough free operational memory to view this complex of a document. Indeed, this specific document literally pegs a 2.8GHz Xeon CPU for half a minute just rendering, it’s that complex.

So what can you do? Unfortunately, not a whole lot. If the PDF is paginated, you can try saving each page as a single PDF and viewing them one at a time. But in my example PDF above, that’s just not a reality – it’s a single, very complex, document that can’t really be split apart.

One thing you can do, though: bug Nokia to start putting more operational ram in their handsets. :)