# How the Mesh and Images were Created:

The following MATLAB code relies on M-Files: dftuv.m, lpfilter.m, and hpfilter.m

## Lowpass Filters

1. Ideal
• `HLPF_ideal=fftshift(lpfilter('ideal', 500, 500, 50));`
• ` mesh(HLPF_ideal(1:10:500,1:10:500))`
• `colormap([0 0 0])`
• `axis off`
• `grid off`
• `axis([0 50 0 50 0 1])`
• ```figure, imshow(HLPF_ideal) ```
2. Butterworth
• `HLPF_btw=fftshift(lpfilter('btw', 500, 500, 50));`
• `figure, mesh(HLPF_btw(1:10:500,1:10:500))`
• `colormap([0 0 0])`
• `axis off`
• `grid off`
• `axis([0 50 0 50 0 1])`
• ```figure, imshow(HLPF_btw) ```
3. Gaussian
• `HLPF_gauss=fftshift(lpfilter('gaussian', 500, 500, 50));`
• `figure, mesh(HLPF_gauss(1:10:500,1:10:500))`
• `colormap([0 0 0])`
• `axis off`
• `grid off`
• `axis([0 50 0 50 0 1])`
• `figure, imshow(HLPF_gauss)`

## Highpass Filters

1. Ideal
• `HHPF_ideal=fftshift(hpfilter('ideal', 500, 500, 50));`
• `mesh(HHPF_ideal(1:10:500,1:10:500))`
• `colormap([0 0 0])`
• `axis off`
• `grid off`
• `axis([0 50 0 50 0 1])`
• `figure, imshow(HHPF_ideal)`
2. Butterworth
• `HHPF_btw=fftshift(hpfilter('btw', 500, 500, 50));`
• `figure, mesh(HHPF_btw(1:10:500,1:10:500))`
• `colormap([0 0 0])`
• `axis off`
• `grid off`
• `axis([0 50 0 50 0 1])`
• ```figure, imshow(HHPF_btw) ```
3. Gaussian
• `HHPF_gauss=fftshift(hpfilter('gaussian', 500, 500, 50));`
• `figure, mesh(HHPF_gauss(1:10:500,1:10:500))`
• `colormap([0 0 0])`
• `axis off`
• `grid off`
• `axis([0 50 0 50 0 1])`
• `figure, imshow(HHPF_gauss)`