Project by Fridman Eduard Supervisor and Escort Dr. Yizhar Lavner SIPL Lab experiment onTime-Scale and Pitch- Scale Modifications of Speech

Time-Scale Modification of Speech is one of important purposes of Speech Processing Applications: Dictation-tape playback TTS systems Post synchronization of film Foreign language studying Speech rate modification for hearing impaired people

Project purposes Introduction of students to TSM system Studying, simulation and comparison of time-scale and pitch scale algorithms Understanding of theoretical background of time- scaling and pitch-scaling algorithms Future development

Theoretical background Introduction to digital model of speech production Introduction to digital model of speech production STFT – Short time Fourier Transform STFT – Short time Fourier Transform Time-scale algorithms Time-scale algorithms

STFT Why STFT? Why STFT? Definition of STFT Definition of STFT Fourier transform interpretation Fourier transform interpretation Linear filtering interpretation Linear filtering interpretation Temporal and spectral properties of STFT Temporal and spectral properties of STFT

Time-scale algorithms Introduction to two main methods of time- scaling – parametric and non parametric Introduction to two main methods of time- scaling – parametric and non parametric Short description of popular parametric methods Short description of popular parametric methods OLA method – main idea, relation to STFT, formulation OLA method – main idea, relation to STFT, formulation

OLA method Defects of algorithm Defects of algorithm What can be done? What can be done? Improved algorithms – WSOLA,TDPSOLA Improved algorithms – WSOLA,TDPSOLA Pitch and pitch detection Pitch and pitch detection

Experiment A – WSOLA (Homework) Understanding of STFT properties – experimenting with window size,type and overlapping Understanding of STFT properties – experimenting with window size,type and overlapping Proof of OLA formula Proof of OLA formula Problems of OLA Problems of OLA Simulation of OLA and WSOLA Simulation of OLA and WSOLA

Experiment A – WSOLA (Lab) Introduction to TSM system Introduction to TSM system Analysis of algorithms implemented in the TSM system Analysis of algorithms implemented in the TSM system Comparison between system output and students output Comparison between system output and students output STFT analysis STFT analysis Studying the role of TSM algorithm parameters Studying the role of TSM algorithm parameters WSOLA with non-uniform time-scaling WSOLA with non-uniform time-scaling WSOLA with speech and general audio signals WSOLA with speech and general audio signals

Experiment B – TDPSOLA (Homework) Pitch scaling – how? Pitch scaling – how? Pitch detection algorithm Pitch detection algorithm Setting up new pitch Setting up new pitch Simulation of TDPSOLA algorithm Simulation of TDPSOLA algorithm

Experiment B – TDPSOLA (Lab) Comparison between system output of TDPSOLA and students output Comparison between system output of TDPSOLA and students output STFT analysis STFT analysis TDPSOLA with non-uniform time-scaling TDPSOLA with non-uniform time-scaling TDPSOLA with multi-pitch signals TDPSOLA with multi-pitch signals

Future work Incorporating parametric methods into TSM system Incorporating parametric methods into TSM system Speech coding using TSM algorithms Speech coding using TSM algorithms Music aided algorithms Music aided algorithms