Speech recognition using a recorder audio stream

Speech recognition using a recorder audio stream

I am developing an app which uses the speech recognition features.
I just want to know how can i Convert a long enough speech into text, for
example a 30 min lecture into text.
as i am trying this with Speech Recognizer but it do not work more than 9
to 10 seconds.
Can anyone suggest some solution or provide any link or any example?
Or is it possible to record an audio an convert it into a text message.
please provide some suggestions.
Thanks in advance...