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Preface
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The MITalk system described in this book is the result of a long effort, stretching
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from the early 1960s to the present. In this preface, a view is given of the work’s
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historical evolution. Within this description, acknowledgements are made of the
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project’s many contributions. In recognizing these contributions, it is best to or-
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ganize them into four groups. First, there is the development of the MITalk system
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itself, its evolution, and the many diverse contributions made to its structure and
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content. Second, there was the 1979 summer course which resulted in a com-
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prehensive summary of the work to that date, and also provided the occasion to
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write a set of course notes. Next, there have been continuing efforts (since 1980)
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which included re-writes of the system’s software, and the efforts to organize this
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book which involved substantial new writing and rule formulations, and explicit
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examples directly keyed to the current working system. Finally, there is the spon-
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sorship of the program’s many facets over the years.
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In the early 1960s, much interest in speech synthesis emerged within the Cog-
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nitive Information Processing Group at MIT’s Research Laboratory of Electronics.
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This group, led by M. Eden and S. J. Mason, focused on the development of sen-
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sory aids for the blind. Many approaches were taken, but it was recognized that
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the development of a reading machine for the blind that could scan printed text and
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produce spoken output was a major goal. Research efforts in both character recog-
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nition and speech synthesis from text were initiated. By 1968, a functional reading
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machine was demonstrated. Once the characters were recognized (using a contour
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scanning algorithm), text-to-speech conversion was accomplished in two phases.
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First, a morph decomposition analysis of all words was performed by using tech-
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niques developed by F. F. Lee (in his 1965 doctoral thesis). A morph lexicon suf-
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ficient for these demonstrations was developed. It was anticipated that any excep-
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tional words not analyzed into morphs would be pronounced by using spelled
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speech. As a result, these words were heard as a sequence of individually
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pronounced letters. The dictionary provided names of the phonetic segments for
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each morph, and synthesis was performed using the algorithms developed and
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published by Holrhes, Mattingly, and Shearme. An analog synthesizer was used to
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amplifiers. The demonstration of this system was impressive, although the
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