How can i find the zero crossing rate of the wavelet coefficients?

i am doing a project in signal processing.,in that i have to apply the DWT to the signal and find the zero crossing rate of the wavelet coefficients ie.,for approximate and detail coefficients.Is there anyone know about this please tell me. Thank you,

Answer 1

[Matt J]

Is this (approximately) what you want?

crossingRate = mean(abs(diff(sign(coefficients))))

[maxina dialin]

sir actually i am doing the project in audio fingerprinting.,so in that i have to find zero crossing rate using 0.5*sum(sign(x(n))-sign(x(n-1))w(n-m) in that for every 'm'th frame i have to calculate the zero crossing rate of the wavelet coefficients(n). but i dont know how to do it. so if i use this, crossingRate = mean(abs(diff(sign(coefficients)))) can i give all the coefficents ie.,ca5,cd1,cd2,cd3,cd4,cd5 at the same time? because if i give all at the same time it will show the error msg(too many input arguments).how can i correct that?