谱线自动提取的小波变换零交叉点方法

将原始光谱进行小波变换，然后研究谱线在小波变换域内呈现的特性，通过引入上、下零交叉点的概念，分析并得到吸收线和发射线分别对应于不同类型的零交叉点的结论。提出一种小波变换零交叉点方法用于提取谱线和拟合连续谱，与传统方法相比，该方法可以同时得到连续谱和谱线，并且无需专门去噪处理，克服了传统方法因拟合连续谱失真和去噪过程中带来的误差导致提取谱线不准确的缺点。通过对恒星、近邻星系等的试验表明，该方法是有效的, 对特征参数计算和基于谱线的光谱分类是非常有利的。

Wavelet Transform Zero-Crossing Method for Auto-Extraction of Spectral Lines

Wavelet transform method is used in this paper. The authors firstly studied the properties of spectral lines in the wavelet domain. By introducing the items of up-zero-crossings and down-zero-crossings, the authors concluded that absorption lines and emission lines correspond to different kinds of zero-crossings. Therefore the authors presented a new wavelet transform zero-crossing method for the extraction of spectral lines and the normalization of continuum spectra. The useful spectral lines can be obtained together with the continuum spectra. The extraction of spectral lines in this paper is a direct method, which avoids the errors caused during the process of noise reduction. The experiments both on stars and nearby galaxies show that our method can be used to accurately extract the spectral lines, which is helpful to the computation of characteristic parameters and the automatic classification of spectra based on spectral lines.