Image fusion of tempo-spatially modulated polarization interference imaging spectrometer

The space-based tempo-spatially modulated polarization interferometer imaging spectrometer (TSMPIIS) scans over an observed area, and acquires the image-spectrum data cubic consisting of a series of the CCD images taken at different times. Every pixel on the CCD image records interferographs with different optical path differences, corresponding to the incident angles changing from maximum, via zero, and finally to negative maximum. To improve the spatial resolution of the color comprised image acquired by TSMPIIS, the panchromatic (PAN) image of high spatial resolution is fused with the color composite image of high spectrum resolution to produce the fused image of both high spatial and spectrum resolution. Based on the characteristics of the TSMPIIS image data, the FFT (fast Fourier transform)-enhanced IHS (intensity-hue-saturation) transform method is used and compared with IHS and WT (wave transform) methods. The experimental results show that the FFT-enhanced IHS method can establish very good trade-off between spatial and spectral quality of the fused image and largely improve the spatial resolution of the color composite image. The fusion method significantly enhances the instrument performance at very low cost.