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Multispectral image sharpening using wavelet transform techniques and spatial correlation of edges

January 1, 2000

Several reported image fusion or sharpening techniques are based on the discrete wavelet transform (DWT). The technique described here uses a pixel-based maximum selection rule to combine respective transform coefficients of lower spatial resolution near-infrared (NIR) and higher spatial resolution panchromatic (pan) imagery to produce a sharpened NIR image. Sharpening assumes a radiometric correlation between the spectral band images. However, there can be poor correlation, including edge contrast reversals (e.g., at soil-vegetation boundaries), between the fused images and, consequently, degraded performance. To improve sharpening, a local area-based correlation technique originally reported for edge comparison with image pyramid fusion is modified for application with the DWT process. Further improvements are obtained by using redundant, shift-invariant implementation of the DWT. Example images demonstrate the improvements in NIR image sharpening with higher resolution pan imagery.

Publication Year 2000
Title Multispectral image sharpening using wavelet transform techniques and spatial correlation of edges
Authors George P. Lemeshewsky, Robert A. Schowengerdt
Publication Type Conference Paper
Publication Subtype Conference Paper
Index ID 70023165
Record Source USGS Publications Warehouse