©copyright Raimo Olavi Toivonen 1983-2021. All rights reserved. Last updated on Jan 30, 2021.

Home  Signal displays 1985-  Multi-envelope displays 1998-  FFT displays 1985-  Cepstrum displays 1983-  LPC displays 1992-  Auditory displays 1983- Loudness displays 1995-  Loudness curves 1998-  Timbre spectrum 1983-  LTAS displays 1992-  Harmonic FFT displays, S/N-ratio 1989-  F0 displays 1983-  F0 histograms in semitone scale 1989-   Computer Voice Fields in Hz scale 1983-   Computer Voice Fields in semitone scale 2017-  Jitter/shimmer 1990-  Waterfall displays 1983-  FFT spectrogram displays 1985-  LPC spectrogram displays 1998-  Auditory spectrogram displays 1985-  Formant charts in Bark, ERB, mel, semitone ja Hz scales   1988-   Synte 2 demo video speech on 8.8.1977 analyzed 2018-  Other links  Formant charts of world languages in Bark scale 2018-

Works   Works before ISA


ISA software

Fonetograms in dB/st scale

My F0 analysis is done by bandpass filtering the time signal and then searching every voice period in the time signal using my unique method. By searching in the time signal, each voice period can be determined with high accuracy F0, and even small variations in the fundamental frequency can be seen.

My unique F0 algorithm also makes it possible to determine the jitter and the shimmer.

My F0 algorithm has been in use for 37 years since 1984 and has been running in real time on the NEC's µPD7720 signal processor since 1985, 36 years ago..

Who else would have done pitch analysis in Finland already on 1984, 37 years ago, and already on 1985 in real time?

Analysis pictures I have coded from the very beginning in Neon object-oriented programming language.

In the pictures the phrase "Ai ai kun on kaunis päivä" (Oh ai when it's a beautiful day) is a voice field and a phonetogram on a semitone scale.

Automatically searches for the dB values ​​corresponding to the highest and lowest tones of all semitones.

Each identified pitch period is displayed separately in the Computer Voice Field.