A new image enhancement technique has been applied to enhance Landsat-4 Thematic Mapper (TM) thermal infrared (IR) imagery and has improved its effective ground resolution from 120 m to 30 m. The technique is based on an adaptive multiband least squares (LS) method for computing an optimal image estimate from reference images, and a frequency domain replacement step. The approach relies on the assumption that at a sufficiently small resolution registered TM imagery data are locally correlated across the bands. Using the local correlation property, visible and IR reference bands are used to predict the thermal IR image data. The prediction estimate is then used to augment the spatial high frequency information in the original thermal data. Preliminary experiments enhancing 120 m IR imagery (simulated degradation) to 30 m resolution show a signal-to-noise ratio improvement of 19 dB.
Victor T. Tom,
Mark J. Carlotto,
Daniel K. Scholten,
"Spatial Sharpening Of Thematic Mapper Data Using A Multiband Approach," Optical Engineering 24(6), 241026 (1 December 1985). https://doi.org/10.1117/12.7973623