1. A method for delineation of characteristic points in an electrocardiogram signal, comprising the step of: (a) processing the electrocardiogram signal to obtain a first order multiscale differential operator wavelet transform, a second order multiscale differential operator wavelet transform, and a third order multiscale differential operator wavelet transform thereof; and (b) locating at least one characteristic point in at least one wave segment of the electrocardiogram signal based on the first order multiscale differential operator wavelet transform, the second order multiscale differential operator wavelet transform, and the third order multiscale differential operator wavelet transform, said at least one characteristic point being at least one of a P-wave peak point, a P-wave on point, a P-wave off point, a QRS-wave peak point, a QRS-wave on point, a QRS-wave off point, a T-wave peak point, a T-wave on point, and a T-wave off point.