Mean shift based auto-extraction of spectral lines for non-emission-line objects

The mean shift algorithm is used. At first, the property that mean shift vectors always point toward local maxima of the density is used to get the pseudo continuum; secondly, mean shift filtering is a good edge preserving smoothing, which can adaptively reduce the amount of smoothing near feature spectral lines, so the authors use mean shift filtering in noise reduction after the normalization of continuum spectra; finally, the authors extract feature spectral lines by setting local thresholds. The experiments on both stars and normal galaxies show that our method can extract spectra lines accurately, which is helpful to the parameter measure and the automatic classification of spectra based on spectral lines.