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List of band math/ spectral math function in ENVI

Applying mathematical operation on satellite image is an important processing step in remote sensing project. Lots of software such as MATLAB, ENVI, ERDAS and PCI Geomatica enable users to carry out these operation . However, the user interface and how to implement the operation into the software make them different with one another. Some software required basic knowledge of programming while other give more user-friendly and easier interface for the beginner. Above all software, one of the easiest software to perform simple mathematical operation on satellite images is by using ENVI.

In ENVI, the tools is called band math. (Basic Tool>Band Math)

Band math in ENVI enable user to perform basic mathematical operation, trigonometric function and  other option such as Boorlean and relational operators. Today, i like to share about the list of mathematical band math operation in ENVI.

  1. Addition (+)
  2. Subtraction – (-)
  3. Multiplication – (*)
  4. Division – (/)
  5. Minimum operator – (<)
  6. Maximum operator – (>)
  7. Absolute value – (abs(x))
  8. Square root – (sqrt(x))
  9. Exponent  – (^)
  10. Natural exponent – (exp(x))
  11. Natural logarithm – (alog(x))
  12. Base 10 logarithm – (alog10(x))
  13. Sine – (sin(x))
  14. Cosine  – (cos(x))
  15. Tangent – (tan(x))
  16. Inverse sine/ Arcsine – (asin(x))
  17. Inverse cosine/ Arccosine – (acos(x))
  18. Inverse tangent/ Arctangent – (atan(x))
  19. Hyperbolic sine – (sinh(x))
  20. Hyperbolic cosine – (cosh(x))
  21. Hyperbolic tangent – (tanh(x))

There are still few more functions, however the list above is the most used ones in ENVI. Thanks you and don’t forget to bookmark us (Ctrl + D).