FFT of a video sequence

How to generate the spectrum?

Answer 1

[Walter Roberson]

Are you looking for something like a spectrogram, http://www.mathworks.com/help/toolbox/signal/ref/spectrogram.html (see also http://en.wikipedia.org/wiki/Spectrogram)

or more like a periodogram, http://www.mathworks.com/help/toolbox/signal/ref/periodogram.html