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Why my result of flaash useing aster data is incorrect?


adel.naseri

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thanks "peralta2794"...

1.I do not think that the differences in spectral profiles of one location in both images is evident. it is possible they have Small differences But not like this Big differences.

2.The scale factor is 10.

3.The area covered by my image is desert therefore doesn't have vegetation or water bodies.

 

 
 
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Dear Cadet,

 

As FLAASH module multiplies the output (surface reflectance data) by 10,000 omitting decimals for faster calculations and lower file size, we should apply this equation:

 

(B1 le 0)*0+(B1 ge 10000)*1+(B1 gt 0 and B1 lt 10000)*float (b1)/10000

 

where;          

le  means less than or equal          

ge means greater than or equal          

gt  means greater than         

lt   means less than

 

The resulting surface reflectance data will lie between 0 to less than unity (0 to <1) suitable for further image spectrometry and comparable with most spectral libraries.

 

I hope that helps

 

Regards

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Dear Cadet,

 

As FLAASH module multiplies the output (surface reflectance data) by 10,000 omitting decimals for faster calculations and lower file size, we should apply this equation:

 

(B1 le 0)*0+(B1 ge 10000)*1+(B1 gt 0 and B1 lt 10000)*float (b1)/10000

 

where;          

le  means less than or equal          

ge means greater than or equal          

gt  means greater than         

lt   means less than

 

The resulting surface reflectance data will lie between 0 to less than unity (0 to <1) suitable for further image spectrometry and comparable with most spectral libraries.

 

I hope that helps

 

Regards

Yes..You have to scale your data using this eq

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