🚀 go-pugleaf

In article <1992Oct30.183655.14435@athena.mit.edu> ninassup@athena.mit.edu  
(Nikos I Nassuphis) writes:
> I need to keep the camera focused onto a
> region of the surface as the stage moves it
> under the microscope.
> 
> I therefore need some type of autofocus.
> I am contemplating a control loop that 
> will maximize the high frequency content of
> the area i want to focus on.

You could try maximizing contrast. Michelson contrast is defined as 
(max - min)/(max + min) over some area. This will be computationally 
faster and easier to program than either maximizing high-frequency 
content or maximizing total energy of non-zero components. Whether or
not it will work will depend on what your image looks like.

Charles Neveu
Neurology Unit
Program in Physiological Optics
UCBerkeley