Calculation of sampling rate and its effect on an Image?

[ramdas]

I know that for a given signal, the sampling frequency Fs must be twice or more than maximum frequency of the signal Fm. It is easy to understand the concept for a 1D signal. But I don't know how to calculate sampling frequency or Nyquist rate for a 2D image.

Also what is effect of over-sampling and under-sampling in case of image (dimensions width⋅height=204⋅226)?

 

[MagicianT]

For video your sampling rate is frame rate per second, or fps 24, 30 etc. Size of the image is second derivation in this case, and it defines ADC conversion rate in elements per second, when all elements taken in the same time snapshot.
Over- and under-sampling has same effect as in 1D , you 'd have aliasing effect if fps lower than frequency of luminosity changes F(lm) of the object on a screen, when visible changes in brightness corresponds to beating fps and F(lm).