This is the data returned when a hand is laid on a projected capacitive touchscreen (same technology as cellphones).
This is an example output of my Matlab function to convert any Z-map into a STL file.
The generated solid has a specified size(max) and thickness (min/max).
It's also possible to choose the degree of interpolation to smooth the output result.
Are included 3 levels of interpolation.
The explanation & script are available here: http://wp.me/p3gI7M-1S