Validation of Multiband Color Signatures

摘要

The practice of remote sensing by the acquisition of imagery from space has promised more than it has delivered. Photographic interpreters schooled in the techniques of information extraction from panchromatic and color infrared single frames and stereo pairs were, in the absence of an established reference for multiband color signatures, relegated to inferential analysis of false-color satellite imagery composited from the digital data of several spectral bands. A principal roadblock to the reliable interpretation of space photography lies with the fickle nature of the color signatures which, pixel by pixel, create the satellite-based digital image. This paper presents one approach to the validation of those color signatures that offers the potential for the evolutionary development of a reference library for multiband interpretation. A solution to the problems associated with the conversion of digital imaging data to analog silver halide hardcopy, the registration of black-and-white film separations, and the introduction of color by additive filtration are presented as prerequisites to the validation of spatial resolution and color signatures in a multiband color composited film negative. Practical color signature validation enables the reliable interpretation of multiband imagery regardless of bandwidth and frequency.