A denoising method based on null space pursuit for infrared spectrum

•The null space pursuit (NSP) algorithm is realized by a differential operator.•NSP is used to extract the components of infrared signal.•The residue of NSP is processed by mean filter to suppress noise.

The reduction of noise in infrared spectrum is of vital importance, as the infrared signal is often buried in excessive noise. In this paper, a novel denoising method based on null space pursuit (NSP) is proposed to eliminate noise in the infrared signal. The NSP is an adaptive operator-based signal separation approach, which can decompose signal into subband components and residue according to their characteristics. The residue is processed by mean filter because it contains very little useful information. Then, the subband components and the filtered residue are used to reconstruct the noise-free signal. Experimental results show that the proposed denoising method is effective in suppressing noise while retaining signal characteristics.