TEXT-TO-SPEECH TECHNOLOGYFerit KILIÇKAYAText-to-Speech Technology (TTS)•Educators in the field of language teaching always try hard to find ways to make language learning enjoyable and attractive for the learners. •Different activities, games, and interesting stories helped language teachers to achieve this aim through many years and they still do. 2Text-to-Speech Technology (TTS)•Today, we have access to many CALL programs that are currently used and tested in language classrooms for teaching grammar, speaking and other skills. •Text-to-speech technology is a common feature of almost any CALL application. 3Text-to-Speech Technology (TTS)•What is Text-to-Speech?'Text-to-Speech' (Speech Synthesis) technology is the ability of a computer to produce 'spoken words'. 4Text-to-Speech Technology (TTS)•The heart of the system is the TTS engine –a sophisticated piece of software that:•parses the text input,•analyzes its grammar, sentence structure, punctuation and capitalization, and•activates voice simulations to produce a vocal rendering of the text. •The data for individual voices, including regional accents, are provided in separate files called "voices". The TTS engine can work with any of the voices interchangeably.5Text-to-Speech Technology (TTS)•The TTS system is illustrated in the following diagram.6Text-to-Speech Technology (TTS)•Today’sTTS technologyis muchimprovedoverthatof evena fewyearsago. •Theoldersystemsproducedtherobotic-likesoundsthatpeopletendtoassociatewithcomputervoices.7Text-to-Speech Technology (TTS)•‘Text-to-speech' technology was basically designed for the visually impaired people. •Text-to-speech software is considered invaluable for the visually impairedsince it enables them to read from the computer screens. •However, it didn't take much attention from language learners and teachers. •This might be attributed to the views on this new technology as Higgins (as cited in Ehsani & Knodt, 1998, p.46) states "Because speech technology isn't perfect,it is of no useat all. If it cannot account for the full complexity of human language', why even bother modeling more constrained aspects of language use." 8Text-to-Speech Technology (TTS)•Although what Higgins said cannot be confronted since speech technology is not perfect in terms of the complexity of human language, it is important to note that it has some possible uses in language teaching and learning. •We also should take into account that technology improves day by day and it is no doubt that what is good today will be better tomorrow.•Ehsani and Knodt (1998) and Sobkowiak (2003) stated that text-to-speech technology will be(or is)a common feature of any CALL application and human language technologies will improve the current software of foreign language teaching. 9Text-to-Speech Technology (TTS)•Currently, there are three computer applications available to home users who want to benefit from this technology, namely, Natural Voice Reader, ReadPlease Plus 2003 and TextAloud MP3.•All these programs are aimed to produce the most realistic human sounding voices. However, Garrett (1998, p. 81) states "This technology isn't at a stage where it can reliably render a target language accent authentic enough for language use." •Before dealing with the performance issue, the first question to be answered is what these applications can do. 10Text-to-Speech Technology (TTS)•In general, these applications using 'Text to Speech' technology can –Read any text in computer (web pages, word documents, rich texts, e-mails, news articles, online books etc.) –Give the option of reading any text and saving it to a file in the form of wav or mp3 files, which gives the opportunity to listen to them later in your MP3 or CD player. –Read any text at any speed and any speaking quality. –Read any text using the voice or any accent (male, female, British English American English, etc.) 11Text-to-Speech Technology (TTS)•The most important consideration perhaps is whether this technology can create authentic speech. In other words, will the speech produced be authentic enough? •To understand this, Natural Voice Reader Enterprise Edition having AT&T Mike and Crystal American English Voices were tested and used to create human-sounding versions of a mini dialogue and a long text.•When compared, it was noticed that the resulting voices were satisfactory in terms of pronunciation and clearness, however; some limitations were noted.12Text-to-Speech Technology (TTS)•Taking language learners into consideration, the following list can be made regarding the uses of these programs: –Advantages–You can listen to any text and any topic (Most EFL listening materials cover a limited range of topics and some of them are rather expensive. –You can adjust the speed of reading according to your own needs. –You can create audio versions from any text (wav or mp3 files). –You can create pronunciation exercises for yourself (A single word can also be read.) –You can create mini dialogues (changing speakers at run times is possible). 13Text-to-Speech Technology (TTS)•Limitations–There is always a difference in terms of intonation and stress. In other words, it still lacks the complexity of naturally occurring speech, resulting in 'dead' sound having no emotions. This is easily identified while these programs are reading rather longer sentences.–It should be noted that there is no limit to the technological advances and acquiring the complexity of naturally occurring speech may be possible in near future. –These programs require newer and faster computers and enough hard disk space to run. (Operation system: windows 98/Me/NT/2000/XP, Processor: 500 MHz, Memory: 128 MB memory, Disk Space required: 500MB +600 MB for each voice.). However, today new computers are highly capable of what is required.) 14Text-to-Speech Technology (TTS)•Examples of how this technology can be used •1. Creating a list of frequently-mispronounced words•Language teachers and learners can create a list of frequently-mispronounced words and save this list as a "wav" for later use. Learners can listen to these words and repeat while the file is placed. Below is an example of a possible list.ForeignInterestingDetermineOccurrencePrefaceComparableCompareComparisonCarriageMarriageNaturalMatureIronCapableBusinessMajorSubtleImpotentSuitableSupport15Text-to-Speech Technology (TTS)•2. Writing short sentences and listening•Language learners can short sentences to the extent that their imagination allows and listen to these dialogues. In this way, this process can be made enjoyable and fascinating. Below are possible short sentences that can be created.•Excuse me, Where is the nearest post office please?What kind of books do you read?What kind of music do you like?What do you do when you are bored?16Text-to-Speech Technology (TTS)•3. Creating short dialogues•Language learners can also write dialogues while changing the speakers of the programs. •Below is possible dialogue that can be created.•Excuse me, Where is the nearest lost property office, please?I'm sorry,Idon't know.Thank you anyway. Not at all. 17Text-to-Speech Technology (TTS)•Reading and listening newspapers online•Language learners can also read newspapers online and save them as wav files for later use. Below is an online article which was saved as a sound file (Audio8) •"A 28-year-old South Korean man has died after playing an online computer game for almost 50 hours non-stop. The man, known only by his family name of Lee, started playing the popular battle simulation game Starcraft on August 3 and was fixed to his seat for over two days. His marathon gaming session was apparently broken only with the occasional toilet break or five-minute nap. Reuters News Agency reports police sources saying the man died from cardiac arrest "stemming from exhaustion".18Text-to-Speech Technology (TTS)•Conclusion•'Text to Speech' (Speech Synthesis) technology has improved a lot and it is ready to be deployed in language learning provided that its limitations are taken into consideration. If instructors are trying to expose students to natural language audio input and 'comprehensible input' (Krashen, 1985) as much as possible, this technology can provide a valuable way of doing it provided that its limitations are fully understood and as Ehsani & Knodt stated "it is used in ways that workaround these limitations. 19Text-to-Speech Technology (TTS)•Recommendations•Based on the discussions, the following recommendations have been made: •'Text to Speech' (Speech Synthesis) technology is ready to be deployed in the second language education and instructors should be willing to explore possible uses of this technology having its limitations into considerations. •Experimental studies are needed to fully understand the possible uses/effects of this technology in language learning situations. Also, language learners' views and needs on the use of this technology will be beneficial in directing the future development of this technology. 20•Sites of interest to readers•http://www.naturalreaders.com/–(Natural Voice Text-to-speech Reader software. You can have your computer read documents aloud, using high quality Natural voice. With Build-in web browser, you can view any web news in the Internet, and have the computer to read any part of the news, weathercast, charting messages, and emails. The application can read word documents, rich text files, and PDF files.) •http://www.readplease.com/–(TextAloud MP3 lets you listen to text you copy to the clipboard. It uses 'Text to Speech' technology which actually synthesizes human sounding speech from ordinary text.) •http://www.nextup.com/–(ReadPlease Plus 2003 will read any text you see on your screen. This can be from your Browser, Email, Word processor, Spreadsheet or any program which displays text.) 21Text-to-Speech Technology (TTS)•http://vlc.polyu.edu.hk/–TTS resources at the Virtual Language Centre of the Polytechnic University of Hong Kong. •http://www.gutenberg.net/–(Project Gutenberg, the brainchild of Michael Hart, is an excellent source of a lot of famous and important texts which are in plain text format. The computer applications above can read these texts.) •http://www.pcww.com/–Winspeech: a TTS program. •http://www.freedomscientific.com/–JAWS for Windows: A remarkable TTS tool. •http://elsap1.unicaen.fr/KaliDemo.htm –KALI, a demonstration TTS package (French) from the University of Caen. •http://www.rhetorical.com/–a TTS interactive demo (male and female voices speaking with American, British, Scottish, and Australian etc). 22Text-to-Speech Technology (TTS)Thanks for your participation.23