Hi, I am trying here because it seems like there are a lot of experts knowing all sort of DSP ++. Have found a lot of answers to othert questions. My problem is to calculate intensity contours of a speech waveform with amplitude +1/-1 expressed in a desibel scale. I have spent 5-6 hours of googling without results. The intensity is defined as : sound intensity = sound power / (4 pi R2) , but here we have a radius that i cant get to fit in. The intensity of a sound wave depends on how far we are from a source. The only thing i have is the waveform and no references to a distance. If i have managed to get this intensity i think i could have used this : sound intensity level = LI = 10 log ( I / I0 ) , where I0 = I0 = 10-12 W/m2 to get the desibel scale. I have used some feature extraction in an application called Praat that does this intensity tracking based on a waveform. The algorithm used there says ; The values in the sound are first squared, then convolved with a Gaussian analysis window (Kaiser-20; sidelobes below -190 dB). The effective duration of this analysis window is 3.2 / (minimum_pitch), which will guarantee that a periodic signal is analysed as having a pitch-synchronous intensity ripple not greater than our 4-byte floating-point precision (i.e., < 0.00001 dB). This algorithm i really dont understand. The values that are squared is it the amplitudes of the waveform ? what does :Gaussian analysis window (Kaiser-20; sidelobes below -190 dB) mean? It also seems that this calculation is done after the pitch extraction as the analysis window is 3.2/minimun_pitch Any matlab experts that can provide code for this algorithm ? Can anybody explain it to a DSP newbie or is it other easier methods to calcultate the instensity contour of the waveform ? I really hope anybody will help me out here :) Tommy, Norway
intensity of sound/speech
Started by ●January 6, 2007
Reply by ●January 6, 20072007-01-06
> >Hi, > >I am trying here because it seems like there are a lot of expertsknowing>all sort of DSP ++. Have found a lot of answers to othert questions. > >My problem is to calculate intensity contours of a speech waveform with >amplitude +1/-1 expressed in a desibel scale. >I have spent 5-6 hours of googling without results. > >The intensity is defined as : sound intensity = sound power / (4 pi R2) >, but here we have a radius that i cant get to fit in. >The intensity of a sound wave depends on how far we are from a source. >The only thing i have is the waveform and no references to a distance. > >If i have managed to get this intensity i think i could have used this : > >sound intensity level = LI = 10 log ( I / I0 ) , where I0 = I0 = 10-12 >W/m2 > >to get the desibel scale. > > >I have used some feature extraction in an application called Praat that >does this intensity tracking based on a waveform. > >The algorithm used there says ; The values in the sound are firstsquared,>then convolved with a Gaussian analysis window (Kaiser-20; sidelobesbelow>-190 dB). The effective duration of this analysis window is 3.2 / >(minimum_pitch), which will guarantee that a periodic signal is analysed >as having a pitch-synchronous intensity ripple not greater than our4-byte>floating-point precision (i.e., < 0.00001 dB). > >This algorithm i really dont understand. > >The values that are squared is it the amplitudes of the waveform ? >what does :Gaussian analysis window (Kaiser-20; sidelobes below -190 dB) >mean? >It also seems that this calculation is done after the pitch extractionas>the analysis window is 3.2/minimun_pitch > >Any matlab experts that can provide code for this algorithm ? > >Can anybody explain it to a DSP newbie or is it other easier methods to >calcultate the instensity contour of the waveform ? > > >I really hope anybody will help me out here :) > >Tommy, >Norway > >>Sorry for the double post. No idee why it happened.