AbstractIn this paper a novel signal‐preprocessing technique that combines the local and multiscale properties of the wavelet prism with the global filtering capability of orthogonal signal correction (OSC) is presented for the pretreatment of spectroscopic data. In this hybrid method, referred to as wavelet OSC (WOSC), a separate OSC filter is applied to each frequency component generated from a wavelet prism decomposition. The combination of wavelet prism and OSC is shown to be complementary, as the prediction results obtained in subsequent partial least squares (PLS) calibrations using WOSC are superior to those obtained using either the wavelet prism or OSC independently. The ability of WOSC to remove undesirable background effects and enhance subsequent PLS models is demonstrated with two near‐infrared data sets. Copyright © 2005 John Wiley & Sons, Ltd.