Normalized Difference Red Edge Index

The normalized difference red edge index (NDRE) is a metric that can be used to analyse whether images obtained from <a href="/facts/Multispectral_image/XIJEawxe">multi-spectral image</a> sensors contain healthy <a href="/facts/Vegetation/nAHr9kjk">vegetation</a> or not. It does this by measuring the amount of <a href="/facts/Chlorophyll/1Sb0NyyM">chlorophyll</a> in a plant.
It is similar to <a href="/facts/Normalized_Difference_Vegetation_Index/WluBtYq8">Normalized Difference Vegetation Index</a> (NDVI) but uses the ratio of Near-Infrared and the edge of Red as follows:

NDRE
          
        
        =
        
          
            
              (
              
                
                  NIR
                
              
              −
              
                
                  RE
                
              
              )
            
            
              (
              
                
                  NIR
                
              
              +
              
                
                  RE
                
              
              )
            
          
        
      
    
    {\displaystyle {\mbox{NDRE}}={\frac {({\mbox{NIR}}-{\mbox{RE}})}{({\mbox{NIR}}+{\mbox{RE}})}}}

The red edge is the part of the <a href="/facts/Spectrum/wPUjkpqI">spectrum</a> centred around 715 nm.
The Index will give a value between -1.0 to +1.0, with a higher value showing a healthy plant environment.

Normalized Difference Red Edge Index open-in-new

Normalized Difference Red Edge Index