A sentence or a singing is to be synthesized with a natural speech close to the human voice. To this end, singing metrical data are formed in a tag processing unit 211 in a singing synthesis unit 212 in a speech synthesis apparatus 200 based on singing data and an analyzed text portion. A language analysis unit 213 performs language processing on text portions other than the singing data. As for a text portion registered in a natural metrical dictionary, as determined by this language processing, corresponding natural metrical data is selected and its parameters are adjusted in a metrical data adjustment unit 222 based on phonemic segment data of a phonemic segment storage unit 223 in the metrical data adjustment unit 222 . As for a text portion not registered in the natural metrical dictionary, a phonemic symbol string is generated in a natural metrical dictionary storage unit 214 , after which metrical data are generated in a metrical generating unit 221 . A waveform generating unit 224 concatenates necessary phonemic segment data, based on the natural metrical data, metrical data and the singing metrical data to generate speech waveform data.
Speech synthesis method and apparatus, program, recording medium and robot apparatus