SIMBAD references

It is difficult to extract multiple overlapping spectra accurately from low signal-to-noise ratio (S/N) 2D astronomical spectrum images. A pretreatment method is proposed in this article to deal with the problem. The combining of the empirical mode decomposition (EMD) algorithm and the fast Fourier transform (FFT) algorithm is used to weaken the effect of the noise of low S/N astronomical spectrum images in order to get more accurate information on spectrum contours. At the end of this paper, experiments for different full width at half-maximum (FWHM) of point-spread functions (PSFs) are presented to demonstrate the effectiveness of the proposed method.