For My Iphone Application I need a speech to text library. Can any one suggest me a solution. After two days digging what i found is Google speech to text API and open source OpenEars Library. Can any one suggest one of these.?Which one is better.?
I don't think the Google APIs are intended for public use. They are services hosted by Google for Android and Chrome. People have reversed engineered the API and built some libraries to let people use it, but I wouldn't build a commercial application that relied on it (unless of course it was an Android or Chrome application).
For iPhone, the great hope is that Apple will expose Siri or Nuance technology in the next OS update. There have been rumors but no announcements. See http://techcrunch.com/2011/05/06/apple-nuance-ios-siri/
For iphone, I know that people have talked about Nuance, iSpeech, and Yapme and others.
I'll point you to different SO questions for some more background. There are lots, but this might be helpful - Text-to-speech (voice generation) and speech-to-text (voice recognition) APIs?
Google Speech API is good but limited to 100 characters. So as long as you only use short sentences, it'll be fine.
OpenEars is a massive library (400+ source files), so it may be a bit inconvenient to implement.
The best solutions are usually the paid ones unfortunately...
After Exploring the different paid solutions in detail, I come up with the http://www.loquendo.com/en/ (now Nuance). This is good option I believe. need Reviews for you guys for better understanding.
来源：https://stackoverflow.com/questions/6776402/speech-to-text-conversion