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I would like to convert spoken words into text so I can use nslinguistictagger in my app. How can I convert speech to text? What are the options? Does openears support voice to text conversion?
Openears will support free speech recognition and text-to-speech functionalities in offline mode.
They have FliteController Class Reference, which controls speech synthesis (TTS) in OpenEars.
They have done an excellent job in speech recognition area.
However, please note that it will detect only the words that you mentioned in vocabulary files.It iss good to work as offline mode to get the better performance.
@Halle: Correct me if I'm wrong.
You have a paid option, Dragon Dictation which is working as online engine.
or use VocalKit: Shim for Speech Recognition on iPhone
I would like to point out that , none of them are accurate than Siri (Siri SDK is not available yet).
OpenEars developer here. Yes, OpenEars does speech recognition and text-to-speech. You need to define a language model or grammar for it containing your vocabulary, but it can be done automatically from an NSArray of word or phrase NSStrings, or a text corpus.
来源：https://stackoverflow.com/questions/15610703/ios-speech-to-text-conversion