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Re: Radar dB values [message #29334 is a reply to message #29327]

Thu, 14 February 2002 00:58

Vincent Schut
Messages: 8
Registered: February 2002

Junior Member

Ronald Greeley wrote:
> I have been trying to synthesize AIRSAR images in the form where I can
> get the dB value for individual pixels off of the image.
>
>
> When I generate a dB image, it gives me values between 0 and 1.
>
> Can anyone provide advice on how to generate an AIRSAR image off of
> which I can get the dB values ??
>
> Thanks!
>
> Kevin Williams
> kkw@asu.edu
>

Usually when you get an output of only 0's and 1's, there is a integer
somewhere in your calculation where it should have been floating point.
Check your formulas and variables; if any of them in your calculation is
integer, the result will be integer too...
I assume you use something like db=10*alog10(rawvalue)? Try putting a
point zero behind the '10', which makes it a floating point constant
instead of a integer: db=10.0 * alog10(rawvalue)

Cheers,
Vincent.

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[Message index]

		Re: Radar dB values By: Pavel A. Romashkin on Thu, 14 February 2002 08:40
		Re: Radar dB values By: Vincent Schut on Thu, 14 February 2002 00:58
		Re: Radar dB values By: Vincent Schut on Mon, 18 February 2002 00:25

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