Question

During digitization samples are taken a distance Δx apart. What is the highest frequency allowed in the image to avoid aliasing?

Answer 1

Aliasing can be defined as the event of overlapping frequency bands. In order to prevent aliasing, a technique called anti-aliasing is used where guard bands are introduced between two separate bands.

The distance = x

The highest frequency allowed should be <= 1 / x to prevent aliasing (when the frequency will be > x, the bands will overlap).

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