Fourier smoothing of digital photographic spectra
Gadiyara Chakrapani Anupama · Indian Institute of Astrophysics · 1990
Fourier methods of smoothing one-dimensional data are discussed with particular reference to digital photographic spectra. Data smoothed using lowpass filters with different cut-off frequencies are intercompared. A method to scale densities in order to remove the dependence of grain noise on density is described. Optimal filtering technique which models signal and noise in Fourier domain is also explained