If it's speech-to-text services you're after, Vocapia Research is in the game, offering a variety of speech technology services and working with their clients to adapt, fine tune or create products that are relevant for specific applications. One of Vocapia's products is the VoxSigma speech-to-text software suite that is suitable for many languages and a variety of audio data types. The VoxSigma API is available as a Web service via a REST API over HTTPS.
In this interview with Raj Kadam, CEO of Viralheat, we will discuss the growth of the company's API and the steps that were taken to reach this point. Their Sentiment API is now getting 300 million calls per week, and the free API allows users to classify text with regard to sentiment.