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Phoneme Approach For Text-to-Speech in SCIAM
jscribner writes "Scientific American is running a feature on IBM Research's Text-to-Speech technology. It discusses the current state of affairs in this field, and describes IBM's phoneme based 'Supervoices' approach. The IBM site provides a demonstration, allowing users to enter text to be rendered to speech, as well as providing several examples in other languages."
Does the poster have something against IBM ... to link an application to a slashdot post?
Even the guys who dont read the articles might be now tempted to try clicking to "enter text" link.
.ACMD setaloiv siht gnidaeR
Phonemes are the building blocks of language not phenomes.
If memory serves me, I believe it was AT&T (?) that used to have a similar webpage with near-perfect text-to-speech, which is hardly the case of this project.
What's so special about it?
I guess IBM didn't have much to say on the matter.
IBM Text-to-Speech Research Demonstration
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Phoneme, a unit of sound in a word. From Dictionary.com: "The smallest phonetic unit in a language that is capable of conveying a distinction in meaning, as the m of mat and the b of bat in English. [... from Greek phnma, phnmat-, utterance, sound produced, from phnein, to produce a sound, from phn, sound, voice...]"
Related to "telephone," "phonics," etc.
If you visit here:
http://www.naturalvoices.att.com/demos/
You'll find AT&T's version a whole lot better. The main problem with voice synthesis is smoothing of phoneme edges, where if it is done too aggressively the speech synthesis can sound too "lumpy".
The other thing is, speech synthesis via phoneme's is very basic practise indeed! I remember having a Currah Speech module for my ZX Spectrum (1982 home computer) - and the first thing you were taught about was phenomes. I'm not entirely sure whats new about this IBM product. It's basically not that much evolved from the mid-90's.
Some of the voices sound okay I guess. Better than Stephen Hawking anyway.
Sorry, but my karma just ran over your dogma.
Oh ... just me? *blush*
There is already freely available open source speech synthesis application for both linux and windows, called Festival created by The University of Edinburgh
I run Mac OS X and in a lot of applications you have the option for the computer to read an entire document. For example, in TextEdit (a simple text editor by Apple) you can go to Edit, Speech, Start Speaking...in the menu and it will read everything for you. There are 10-15 different default voices to choose from, and built into the OS you can control pretty much everything by speech and get information by voice.
How does this compare? I think it is at least at the same level, if not further along! Good work Apple for being in the game, if not ahead of the game on this one.
IBM is not alone to work on text-to-speech technology and to have demos where you can type a phrase and listen to it. The Bell Labs Text-to-Speech system (TTS) has its own page featuring fun demos. "You can play with our basic interface for some of our Text-to-Speech systems: American English, German, Mandarin Chinese, Spanish, French, Italian and Canadian French." This page is pretty old (it makes references to Netscape 3!!), but the demos still run fine.
mmm. I hope the server can take a slashdotting...
The TTS interface is C++, but it comes with a program that will compile text into AU files. I wrote the following script to change those AU files into mp3s:
speakfile is a slightly hacked version of the demo program IBM ships. Unfortunately, /.'s lameness filter doesn't like C++ code. :-(
It's petty messy C++ hacking on my part, anyway. The Perl program is based on the CPAN module Audio::SoundFile. It's also hacked from a demo script that shipped with the module.
mmm. There was indenting in code at one point. Sigh...
I want to know what's going on with speech-to-text, and will I be able to dictate rather than type a novel any time soon? (Preferably with some form of intelligent speech recognition, so it doesn't end up with passages like "She, ah... walked, no strode into the room to find, uh, er, dammit, did I say Rob left the tape on the counter or the desk? Oh, bloody hell. Hello? No, I'm not interested in double glazing. How did you get this number anyway? Bye. Where was I? Oh, crap! Computer, pause-")
You must think in Russian.
I have a master's in linguistics, specialising in speech processing and the like, and I don't really believe in phonemes.
/t/, I'll write it down like that". You know yourselves how often words in English bear no relation to their spoken forms.
In the beginning, there was the word. And the word was spoken. A long, long time later came writing. Most early forms of writing seem to have been pictographic. Eventually that started to be a bit too complicated for most, and somewhere along the line we switched to trying to represent the sounds of the words that we used. These writing systems had to be sort of retrofitted onto the sounds we used, and so they were never going to amount to a perfect transcription of the sounds used. Huge alphabets quickly become unwieldy, and while there is a great deal of variation between languages in terms of how they deal with these issues, in most cases sounds end up being shoehorned into one category or another - "oh, that's sort of a
Anyway, a long time after that, people got interested in phonetics. Conditioned as we were into thinking of words as collections of letters, along came the concept of the phoneme, which, as somebody said above, is the smallest individual unit of speech which can be distinguished from other such units. Phoneticists set about mapping all the sounds of all the languages in the world to phonemes, and we got the international phonetic alphabet.
Later still, we managed to invent machines which allowed us to analyse sound spectra. Run a spoken utterance through one of these and what you'll see most certainly isn't a succession of distinct sounds. Truth is, our brain does so much work on the raw sound that our perception of the sounds is entirely different from the reality. "Phonemes" don't just start and end neatly - they overlap massively. A single vowel can affect maybe the preceding four segments and the following six because of the effects of reconfiguring your vocal tract. The next sound might do the same. And the next one... As you can probably imagine, it's a pretty messy picture really. Believe me, I have suffered greatly trying to segment voice spectra by hand.
The point of all this is that when we started speaking yonks ago, we were making use of the vocal tract nature (God, natural selection, take yer pick, I don't want to get into an argument about it) gave us. We weren't thinking of phonemes and stuff, we were just making noises subject to the limitations of the equipment we had. The notion that this is a nice, ordered system of sounds is an artifical one imposed by us in an attempt to make sense of it all, and it amounts to an expanded version of an oversimplified system (the alphabet). Now, we all know what happens with lossy compression...
Simply drawing lines down the spectrogram in the name of making it easier to work with just throws away subtlety, so that when you use a phoneme-based TTS system you get a series of disjointed sounds with perhaps some token effort at coarticulation (i.e. the phenomenon of overlapping sounds described above), and it's always going to sound awful. The consequences for speech recognition are much worse (sure, your hidden Markov model-based systems working with sequences of two or three phonemes are pretty effective, but they'll never be 100% successful in my opinion).
In short, what you have here's an engineer's approach to art. It's like taking a painting by your favourite artist and turning it into a 256-colour bitmap, then analysing the result and trying to make new paintings in the same style.