The authors collected the spectral data of wheat in different occasion , got rid of the noises which happened in the course of measuration by ways of averaging near spectral data and ways of setting limiting figure to amplitude , then the most important characteristic points were gained 然后根據實測的3個不同時期小麥的反射率曲線,在進行了均值去噪處理之后,設定振幅閥值,排除了殘余噪音干擾,從而提取了曲線最重要的特征點。