Hi,
You stated 17 to 20 frames per second, which is actually
blazingly fast, so I assume you actually meant 1 frame per 17 to 20 seconds, which indeed would be slow. :)
I suspect the slowness you see is due to an insufficient graphics card. Tracking and calibration speed is largely dependent on the GPU speed of your graphics card. I have a fairly modest Nvidia GTX 460 and currently get about 1 frame per 0.67 seconds or about 89 frames per minute. That's not the fastest time you'll here about here but it's quite good and certainly fast enough for production work.
You can find benchmarks here:
http://wiki.ipisoft.com/index.php?title ... ccessoriesScroll down to video cards for the list.
If your computer does not have GPU (for example, it's a laptop with stock Intel Graphics) then tracking and calibration performance will certainly be disappointing. Many users who use a laptop to capture their motions, will transfer the data to a desktop computer with a good graphics card and do the calibration and tracking there. (FYI, I used to do it this way. Now I capture and track using the same desktop computer and my workflow has been more reliable this way. This is just me though; you may find a different workflow more fitting depending on your hardware and shooting location.)
Hope this helps.
G.