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Relationship between mixing proportions and
NDVI.
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The Normalized Difference Vegetation Index (NDVI) is defined
by using the reflectance values of a pixel in the red and infrared bands. |
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where B1 is the red band and
B2 is the infrared band.
Let us assume that a is the fraction of vegetation in the pixel.
a can be calculated with the help of various spectral unmixing methods.
Both a and NDVI give an estimate of the vegetation cover of the ground.
Which of the two is better to use?
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Advantages of using NDVI
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Disadvantages of using NDVI
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Advantages of using the mixing proportion a
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Disadvantages of using the mixing proportion a
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Comparison of the two indicators
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