Figure 7. (a) Power spectrum of CASI frame 1(b) after filtering out the high spectral frequencies as in spatial mode sampling 
with a 10 pixel wide Gaussian transition zone. Only the lowest 16 spectral frequencies are non-zero of a possible 
128. (b) Power spectrum of CASI frame 1(b) after filtering out the high spatial frequencies as in spectral mode 
sampling with a 10 pixel wide Gaussian transition. Only the lowest 16 spatial frequencies are non-zero of a possible 
128. (c) Power spectrum of CASI frame 1(b) after filtering using the proposed cross method which combines the 
spatial and the spectral mode signals with a 10 pixel wide Gaussian transition. The cross is 16 wide both the spectral 
and spatial frequency directions, (d) Inverse Fast Fourier Transform (IFFT) of 7(a). (e) IFFT of 7(b). (f) IFFT 
of 7(c). (g) Difference between the original image 1(b) and the IFFT of the spatial mode sampled image 7(d). (h) 
Difference between the original image 1(b) and the IFFT of the spectral mode, sampled image 7(e). (i) Difference 
between the original image 1(b) and the IFFT of the cross sampled image of 7(f). See figure 3 for the orientation and 
axes labels for all the power spectra images. 
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