A new artificial speech signal for objective quality evaluation of speech coding systems

Abstract

This paper describes a new artificial speech signal (ASVQ Artificial Speech by Vector Quantization technique) which reflects the average characteristics of the human voice. The ASVQ is intended for use as a test signal in the objective evaluation of speech coding system quality.To obtain the average characteristics, a very large speech data base is analyzed. The ASVQ generation method which reflects the extracted average characteristics of the human voice is formulated. This method applies vector quantizing analysis to the speech data base. The LPC speech synthesis circuit is used to reproduce the average characteristics. Finally, the new artificial speech signal is compared with a human voice and the estimation accuracy of the subjective quality of speech coding systems and nonlinear distortions is evaluated.

Multimedia Quality Prediction Methodologies for Advanced Mobile and IP-Based Telephony

“…We proposed an artificial voice as a test signal in the objective quality assessment of coded speech because a real speech signal depends on the speaker, and a conventional sinusoidal signal is insufficient for low bit-rate coding [13]. Figure 9 shows the generation method for the artificial voice using a PARCOR synthesizer.…”

Avaliação objetiva de qualidade de codecs de voz na faixa de telefonia

“…As medidas objetivas existentes podem ser classificadas em 3 diferentes classes: medidas temporais, baseadas na análise temporal da forma de onda do sinal [12]; medidas espectrais, baseadas na estimação de parâmetros da representação espectral do sinal [13]; e as medidas psicoacústicas, baseadas em modelos de percepção da fala e que levam em conta o mecanismo de audição do ouvido humano [14]. Existem ainda técnicas mistas, mesclando aspectos de duas ou das três classes [15]. A seguir, são apresentados alguns exemplos de medidas pertencentes a cada uma dessas classes.…”