hi there, i was going through a paper on using hilbert transform for edge detection in image processing.It said over there that the hilbert transform works better than differentiation for edge detection as it has longer impulse response which helps reduce the effect of noise.I am new to the subject and dont understand what exactly does a longer impulse response mean.??.and how does the impulse response of a system determine its susceptibility to noise..??..and ya what is the impulse response of the hilbert transform..i think its [-j.sgn(f)].correct me if i am wrong but does a longer impulse response mean that it covers a larger band of frequency. thanks in advance
Impulse response of the hilbert transform
Started by ●March 30, 2009
Reply by ●March 30, 20092009-03-30
On Mar 30, 8:02�am, "Anex" <anex.stormri...@gmail.com> wrote:> hi there, i was going through a paper on using hilbert transform for edge > detection in image processing.It said over there that the hilbert transform > works better than differentiation for edge detection as it has longer > impulse response which helps reduce the effect of noise.I am new to the > subject and dont understand what exactly does a longer impulse response > mean.??.and how does the impulse response of a system determine its > susceptibility to noise..??..and ya what is the impulse response of the > hilbert transform..i think its [-j.sgn(f)].correct me if i am wrong but > does a longer impulse response mean that it covers a larger band of > frequency. thanks in advanceHello Anex, You can find the impulse response of a Hilbert transform in this paper. It gives the theoretical response. It is essentially 1/t. http://www.claysturner.com/dsp/HilbertTransforms.pdf But you can design via a Parks-McClellan algorithm practical varsions of Hilbert transforms. But since you say you are doing edge detection, you may find this article helpful. http://www.claysturner.com/dsp/FIR_Regression.pdf Clay