Concentrated Spectrogram of audio acoustic signals - a comparative study

Krzysztof Czarnecki , Marek Moszyński , Mirosław Rojewski

The paper presents new results of time-frequency (TF) analysis of audio acoustic discrete-time signals. As a method of the analysis the authors propose to use the energy concentrating spectrograph also known as "Reassignment method" or "Cross- spectral method". This approach involves signal’s local group delay (LGD) and channelized instantaneous frequency (CIF) to purposely redistribute in TF plain all Short-time Fourier transform (STFT) lines. Some comparisons of classical and concentrated spectrograms of various musical instruments including violin, flute, piano and guitar are presented. Various features of signals especially instantaneous frequency (IF) and amplitude modulation (vibrato) of their components and sound onsets are illustrated and discused.

Mots clés: acoustical imaging; cross-spectral method; reassignment method; time-frequency analysis

Domaines: Acoustique [physics.class-ph]

Krzysztof Czarnecki, Marek Moszyński, Mirosław Rojewski. Concentrated Spectrogram of audio acoustic signals - a comparative study. Acoustics 2012, Apr 2012, Nantes, France. ⟨hal-00810604⟩