I am working on a iphone apps in which i am storing the voice of users as audio file and want to display in text.
How it will be ...any idea about APIs ??
Thanks
Have you seen CMU Sphinx ?
Particularly, pocket sphinx (written in C)
While more recognition oriented, it's been used for transcription before, so it will depend on what exactly you need:
Further, have you considered a non-native/local API, i.e. a web service you could call with your voice data, or are you adamant about a native library/API ?
For example, Ribbit has a platform for these sorts of things, and does support transcribing voice to text
"How do I enable voice-to-text transcriptions? Available as a paid service, voice-to-text transcriptions are automatically available through the Ribbit API. Please use the $25 Free signup credit to try the service."
You will have to develop the voice recognition engine yourself I'm afraid. No library that I know of can do this. Apart form that, the iPhone CPU would probably not be powerful enough.
There is one app that does this already: Jott. The way they do it is to send the file to transcribers in India! (source)