I am writing an audio streaming plug-in for the Opera browser targeting the 6600 device (series 60 version 2). The streaming part is working fine, but it only works with uncompressed audio. To work with compressed audio, I have to convert the audio data before playing it back... I've been playing with the CMdaAudioConvertUtility class of MMF (the new multimedia framework), but based on my tests here, it seems like you can only convert entire files from one format to another using it, and not just audio fragments that I receive as a stream. Only the first audio block contains the file header and CMdaAudioConvertUtility seems to get confused about subsequent audio blocks without headers and returns me an error. Now there is also a low-level class called CAmrToPcmDecoder that I think I might be able to use, since it supports the decoding of audio frames and not just complete audio files. The problem is that from what I understand, this class is deprecated at best and incompatible with the new MMF as well. I can't find documentation about it except for code and pseudo-code posted in various newsgroups. I was wondering what the Nokia people would have to say about this, what they recommend that I do.

Summary question: How do I convert an audio file from one format to another using the MMF when I don't have the entire file at once?


Edison Thomaz