Editing Festival Speech Synthesis System (1997) (section)

== Historical Context ==
Prior to the 1980s, early synthesis systems commonly employed a string re-writing mechanism as their primary data structure.<ref name=":0" /> This mechanism stored linguistic representations as strings and involved rewriting these strings with extra symbols during processing. The main drawback of this approach was the merging of diverse elements, such as words, phrase symbols, stress symbols, and phonemes, into a single string. This approach proved clumsy because it necessitated parsing the string each time a module was called.

Between the 1980s and the mid-1990s, with advancements in programming, Multi-Level Data Structures (MLDS) were introduced into speech synthesis, notably in systems like Delta. MLDS organized linguistic information into separate streams, typically linear lists or arrays of linguistic elements. While it provided some structural organization, it faced limitations in representing non-linear structures, making the handling of tree-like structures challenging. Additionally, as new streams were added, the task of establishing connections to ensure full connectivity became increasingly complex.

In 1996, the development of the Festival Speech Synthesis System commenced, and it quickly emerged as a versatile tool for creating new voices. The Festival system introduced a departure from linear lists by allowing for graph structures, offering greater efficiency in representation. Furthermore, items could be included in different modules, enhancing the system's flexibility. Different modules worked in harmony to produce synthetic speech.<ref>N.Kayte, S., Mundada, M., & Kayte, C. (2015). Speech Synthesis System for Marathi Accent using FESTVOX. ''International Journal of Computer Applications'', ''130''(6), 38–42. <nowiki>https://doi.org/10.5120/ijca2015907024</nowiki></ref> This enabled the handling of complex relations and the efficient calculation of information on-the-fly.

Since the 21st century began, Festival has continued its rapid development. Its open-source nature has made it a magnet for researchers and developers worldwide. They have made significant contributions to the system by introducing various speech synthesis engines and language models, thus enabling support for multiple languages and a wide array of application domains.<ref>Rajan, B. K., Rijoy, V., Gopinath, D. P., & George, N. (2015). Duration modeling for text to speech synthesis system using festival speech engine developed for Malayalam language. ''2015 International Conference on Circuits, Power and Computing Technologies [ICCPCT-2015]'', 1–5. <nowiki>https://doi.org/10.1109/ICCPCT.2015.7159332</nowiki></ref><ref>Clark, R. A. J., Richmond, K., & King, S. (2007). Multisyn: Open-domain unit selection for the Festival speech synthesis system. ''Speech Communication'', ''49''(4), 317–330. <nowiki>https://doi.org/10.1016/j.specom.2007.01.014</nowiki></ref>