- 1740 - 
  
  
   
    
   
   
    
  
     
      
North Carolina/Williams 
   
| (a) black and white airphoto (b) Landsat contrast enhancement 
FIGURE 4.1. COMPARISON OF A CONVENTIONAL BLACK AND WHITE AIRPHOTO AND A LAND- 
| SAT CONTRAST ENHANCEMENT OF A FOREST TRACT IN NORTH CAROLINA. The LANDSAT 
| display (b) was originally prepared as an MSS band 4, 5 and 7 color IR composite and as a color image is 
| generally much easier to interpret than the black and white photo (a). However, even as a black and white 
| rendition, note the similarity of the spatial information contained in both images at this common scale. 
| The LANDSAT image date is 26 February 1974 and the airphoto image date is 15 March 1974. 
TABLE 4.1. VERIFICATION OF THE LANDSAT CLASSIFICATION OF FOREST COVER RELATIVE 
TO AIRPHOTO INTERPRETATION. The table contains the results of a comparison of 232 randomly 
| sampled pixels from the LANDSAT final classification map in Fig. 4.1, with a photointerpreter’s inde- 
pendent delineation of the same area using stereo 70 mm color infrared airphotos at a scale of 1:36,000. 
  
  
  
  
  
  
  
  
  
  
  
| 
| 
| Photointerpreter Classification of Aerial Photos 
| Partial 
Closed Pine Open Pine Computer Percent 
Hard- Canopy Canopy Canopy Regen- Clear- Pixel Agree- 
wood Pine Closure Pine eration cut Count ment 
| 2 Hard- 
| Q | wood 30 1 1 32 94% 
| à | Closed 
€ Canopy 9 5 2 16 or 
| S| Pine 56% 
| '6 | Partial 
| S | Pine 27 or 
= | Canopy 6 15 5 1 56% 
.S| Closure 96% 
= 
‘| Open 
5 | Canopy 3 53 5 61 or 
= | Pine 87% 
o 
| à Regen- 63 or 
| €| eration 1 1 17 37 7 59% 
| 3] Clearcut 15 18 33 54%