Using Speech Input API

The Android SDK support an easy integration of speech input into native applications. We need just to send out an intent RecognizerIntent (no permission is required) to call any available voice recognition service in the phone (e.g. Google Voice, Nuance Dragon API for mobile). Then, a list of recognized word is send back to the application which can capture them in the onActivityResult method. Here is how to send the RecognizerIntent:

int REQUEST_CODE = 1234;
Intent intent = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH);
intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL,
                RecognizerIntent.LANGUAGE_MODEL_FREE_FORM);
intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE, Locale.ENGLISH);
intent.putExtra(RecognizerIntent.EXTRA_PROMPT, "Transalation Demo...");
startActivityForResult(intent, REQUEST_CODE);

The next code snippet shows how to handle the callback message in the onActivityResult method:

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent intent) {
   if (requestCode == REQUEST_CODE && resultCode == RESULT_OK) {
      ArrayList<String> matches = intent.getStringArrayListExtra(RecognizerIntent.EXTRA_RESULTS);
      String text = matches.get(0);
      String translated = translate(text);
      if(translated != null) {
         Toast.makeText(this, translated, Toast.LENGTH_LONG).show();
      }else {
         Toast.makeText(this, "Unable to contact translation service", Toast.LENGTH_LONG).show();
      }
   }
   super.onActivityResult(requestCode, resultCode, intent);
}

The two snippets were inspired from other interesting posts that can be found hereor here.  The Google official post on how to use Speech Input in Android through Google's Voice Search application can be found here.

DroidTranslator

As an example of using speech as user input I made an Android application that translator the user voice message from a language to another. The project is open source, this is link to the project GitHub repository. The following snapshot of the application was taken with Android Screencast.

I used the MyMemory language translation service, but there is planty of similar service, here is some available translation API:

• Google Translate API a paid service, a Java wrapper for this API can be found here.
• Microsoft Translator APIs a free service for less than 2M translated charater per month, similarly a Java wrapper can be found here.
• Mygengo Translation API.a RESTful api with OAuth
• Speaklite Translate API. a professional service.
• WebServiceX.Net Translation Engine a web service accessible via SOAP and XML.An example of how to use this service can be found here Translation Web Service Java Tutorial .
• MyMemory service is a human made translations database, it  provides a free to use API.

Here is a demo of the application: