Amplitude of Signal after performing FFT Analysis

[johnsold]

Ronak,

Can you run your VI and capture the line profile for the black and white bands of interest?  If you stop the VI with Line Profile showing that data, then go to Edit >> Make Current Values Default.  Save the VI with the new default values and post that.  By doing this we can work with your real data without needing to have the Vision toolkit or your test images.

Lynn 

[shahronak]

I've attached the vi with default values.

Thanks,

Ronak

[johnsold · Accepted solution]

Ronak,

The amplitude of a sine wave is the value from the mid point to the peak, not the value from minimum to maximum.  Your line profile shows minimums at zero and maximums from 143 to 174.  This means that the amplitude of the signal is from 72 to 87.  You also have a large offset of about 78 which appears as the large DC or zero frequency component in your spectrum.

After correcting for those the calculated amplitude is 89.2, which seems quite reasonable.

Lynn 

[shahronak]

Thank you!

 I didn't think of that.

Ronak