After working with the lattice match method for measuring the period, I thought there would possibly be a simpler method given the type of data I'm working with.
Suppose I do a match metric only on the scanline plot. I would compare scanlines separted by time (in frames) and use a simple match metric (sum of absolute differences.) I also know the typical period the radar and can limit the match search window.
As shown above, a match matrix
would be generated by:
(1)
Where Tmin and Tmax are the minimum and maximum period times.
is the pixel value at scanline
at time (or frame)
A plot of
for the stabilized scanline image is shown below:
If everything was ideal, there should be a vertical minimum channel at the period location (72 frames).
Taking a look at the 3D meshplot shows this behaviour:
If suspect that I can take the matrix
and stack the rows by summing them together and select the frame that has the minimum value. That frame will correspond to the periodic rate. This indeed is the case with value of 73, which is really close. If I do the same calculation with the raw scanline image, I get a value of 71 frames. I definitely need more data to test this idea.
As shown above, a match matrix 
If everything was ideal, there should be a vertical minimum channel at the period location (72 frames).
If suspect that I can take the matrix 
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