# Fourier descriptor

Statement :

BY 1D Discrete Fourier transform, obtaining its spectrum and using first few components of spectrum to describe $g(r)$ , where $g(r)$ is probably of pixel values $r$.

My question :

Does spectrum get effect by increasing or decreasing of fourier co-efficient ? I understand the Fourier Co-efficient helps to generate different shapes of one object depending on the number of fourier co-efficient.

What would be effect on spectrum with different Fourier co-efficient ? I think our spectrum will get change depending on fourier -coefficient . like if you describe a shape with 4 fourier co-effcient then the spectrum will be drawn by considering only 4 components . AS you increase the fourier co-efficent I think spectrum shape will also increase .

If I am wrong in understanding then please clear it to me , thanks