Institute of Information Science and Technologies Signals

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Institute of Information Science and
TechnologiesSignals Images Laboratory
(SI-LAB)Research Area of Italian National
Council of ResearchesPisa, Italy
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Signal processing research activity (since
1962) Mainly in the fields - biomedical
applications neurology signals , cardiac
pacemaker-1966 patent) - industrial and medical
imaging Non Destructive Testing, Radiology. -
computer music system (audio terminal TAU2, 1970
- 1975)
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Current areas of interest-activity on
Audio/Musical Signal Processing
Signals Images Laboratory (SI-LAB)

• Audio/Music signal analysis and synthesis
• Systems for real time DSP applications and
  multimedia
• Human-machine interfaces for sound synthesis
  control

• Applications
• Audiometry/audiology and hearing aids for deaf
  persons
• Noise control and binaural noise dosimetry
• Base band processing in modem and FM coders
• Novel techniques to play computer music

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Project goal Improve the quality of music
perception in ipoacousic (deaf) people
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• BASIC HEARING LOSS MEASUREMENT
• Tonal liminar audiogram
• (typical diagram - dB loss vs frequency
• Voice test (Italian)
• list with meaning-full ( CANE, FELCE,
  GIGLIO.)
• list with meaning-less logotomi
• (.KEFI, SORI, PEFI..)
• Musical test (There arent)
• (future work)

• .

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Experiments made by setting adequate
amplification in the high frequency range of the
audio bandwith by a special equalizer and drive a
normal headphone apply to a deaf person
MK3 SEED srl board (no low-power) DSP lab.
prototype with MK3
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Preliminary (Italian) voice test results
Two-sillables 51 72 80 Difficult
two-sillabes 26 50 64 Meaning-less
Logotomi 10 26 30
Future work more tests and design of audio
stimuli sets for the evaluation of the music
perception
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Other experiments with analog/digital prototype
devices
A-flat equalization B-Max treble gain, cut freq.
9 KHz C-Min treble gain, cut freq. 700 Hz D-Max
treble gain, cut freq. 700 Hz
OP-AMP Block diagram of portable device (with
LMV934, TDA2822)
Low power Dream DSP starter kit (recent ATMEL
grant) (work in progress) TM
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The pureCMusic (pCM) framework as
open-source music language
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The pureCMusic (pCM) framework gives the
possibility to write a piece of music in terms of
an algorithmic-composition-based program and of
synthesis algorithms. The running composition
can also be controlled by data streaming from
external devices (e.g. MIDI) for giving
expressiveness to realtime performances
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Example of a very simple composition float
vol,freq // communication variables BeginOrch
float alfavolSinosc(sinT,freq)
outLR(alfa,alfa) DefOrchestra Ther()
//name of the orchestra sinosc sinTnewOsc()
//declaration of an oscillator EndOrch void
Score() float hor,vert InitpCM
OrchestraTher // The Ther orchestra is
activated Movement GetMouse(hor,vert)
freq100.hor1000. volvert
EndMovement ClosepCM
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• ToolkitsA composition makes use of the
  functions belonging to the original library which
  puts the pCM framework at work at both Score and
  Orchestra levels. This library consists of three
  different groups of functions named toolkits.
• DSP toolkit
• deals with the synthesis and processing of sound
  and groups elements such as oscillators, envelope
  shapers, filters, delay lines, reverbs, etc..
  (Orchestra level).
• Events toolkit
• deals with the generation and the scheduling of
  events including timing and management of
  external events (Score level).
• Commands toolkit
• manages messages coming from and sent to the
  Midi interface, controls the activation of the
  computer built-in CD player, allows to directly
  record onto memory the audio signal and to store
  it onto disk as .aiff or .wave file, provides
  miscellaneous mathematical functions (Score
  level).