Multispectral data was obtained over this test site on 13 November 1968 to 

 evaluate the Bendix 9-channel scanner for use in crop classification studies. 

 Six of the nine channels were recorded on the seven-channel analog tape 

 recorder used at that time and subsequently played back in the electronic 

 processing laboratory. A grey scale presentation of the reflectance in each 

 wavelength region was in the resulting imagery. The reflectance range in 

 each channel is known from preflight calibration and allows reflectance 

 values to be placed on each resolution element on the ground. The analog 

 processing laboratory allows any channel or combination of channels to be 

 recorded on film and permits processing coefficients to be applied to any 

 channel. The coefficients may be selected from digital data extracted 

 from the original analog tape after computerized statistical analysis has 

 been performed. In this way targets of interest are enhanced and the 

 backgrounds suppressed. 



Two statistical methods were employed in an attempt to enhance 

 the agricultural targets of interest. Before the data was analyzed it was 

 submitted to processing to produce unenhanced imagery for selection of 

 the areas to be sampled. Seven thousand digital samples of the selected 

 areas were then obtained for which ground truth was available in the form 

 of crop identification. The first statistical method applied was factor 

 analysis. The linear combinations of the original data channels specified 



27-4 



