A three-camera multispectral digital video imaging system

This article describes a multispectral digital video imaging system for remote sensing research. The system is comprised of three charge coupled device (CCD) analog video cameras, a computer equipped with an image digitizing board, a color encoder, and super (S)-VHS portable recorder. The cameras are visible/near-infrared (NIR) (0.4-1.1 mu m) light sensitive. Two of the cameras are equipped with visible yellow-green (YG, 0.555-0.565 mu m) and red (R, 0.625-0.635 mu m) filters, respectively, while the third camera has a NIR (0.845-0.857 mu m) filter. The computer is a 486-DX50 system that has an RCB image grabbing board (640 x 480 pixel resolution). The NIR, R, and YG image signals from the cameras are subjected to RGB inputs of the computer digitizing board, thus giving a color-infrared (CIR) composite digital image similar in color tonal rendition to that of CIR film. The hard disk can store 1000 CIR composite images. In addition, the cameras' signals are also subjected to a color encoder that provides an analog CIR composite which is stored on the S-VHS recorder. The analog CIR imagery recording serves as a back-up in the event the computer malfunctions. A global positioning system (GPS) is also integrated with the imagery. The system provides high quality digital video imagery that is superior in resolution to analog video imagery. Image examples are given demonstrating its application to natural resource assessment.