Development of exploratory research tools based on TANDEM-STRAIGHT

Abstract

This article introduces a new set of tools based on TANDEM-STRAIGHT, a fundamental reformulation of STRAIGHT, a speech analysis, modification and resynthesis system introduced in 1997. STRAIGHT has been used in a wide range of speech-related research as a flexible tool for implementing experiments and applications though its scientific foundation was not well established. TANDEM-STRAIGHT introduced a solid basis to resolve this difficulty while preserving the underlying concept of STRAIGHT. TANDEM is a procedure for estimating a temporally static power spectral representation of periodic signals. Together with this representation, the consistent sampling theory enabled complete reformulation of entire algorithms of STRAIGHT and led to a new implementation. This new implementation was applied to develop a set of new tools: temporally variable multi-aspect speech morphing tools, a graphical user interface (GUI) for manipulating STRAIGHT and morphing parameters, and procedures for preparing stimuli for perceptual experiments.