Combined multiresolution (wide-band/narrow-band) spectrogram
Shiufun Cheung, Jeong Sik Lim · IEEE Transactions on Signal Processing · 1992
Existing speech spectrograms-the wideband spectrogram and the narrowband spectrogram-are either deficient in time or frequency resolution. The authors present a method to combine the two spectrograms by evaluating the geometric mean of the corresponding short-time Fourier transform magnitudes. The combined spectrogram preserves the desirable visual features of the originals.>