Hi,

I want to play streamed mp3 in my S60 2nd edition phones like N70 and 3230.
I am using CMdaAudioOutputStream class. since in s60 2.1 phones,using this Api I can only play PCM data, I need to convert the mp3 data received from the network into pcm data. since this devices have and inbuilt MP3 decoder can i use the decoder to decode my mp3 data frame by frame? Using CMMFCodec once i succesfully converted from ARM to PCM using the ProcessL function. Can I use the framework to convert mp3 to PCM buffer by buffer using

CMMFCodec::NewL(KMMFFourCCCodeMP3, KMMFFourCCCodePCM16)

Or do I need to use a decoder like madlib. Ya in devices below S60 V2.1 Mp3 decoders are not available and I need to use a decoder.

regards,

__________________
Prasanna Vignesh
MCPD | Web Developer

not sure if this fit your requirements, but have you looked into the Nokia's open source internet radio project. It is infact playing MP3/AAC coded streams, and AFAIK the streaming engine implementation would also be free.

hi,
I have seen the Nokia internet Radio project. But its basically for phones with 2nd edition FP2 and above which can directly play MP3 and AAC formats.

__________________
Prasanna Vignesh
MCPD | Web Developer

Hi,

I am able to use the inbuilt mp3 decoder in 3230. using CMMFCodec::NewL(KMMFFourCCCodeMP3, KMMFFourCCCodePCM16) but there are lots of issues. I am able to decode the mp3 buffer to PCM16.
I have taken the source and destination as a pointer to 8 bit descritor TDes8* and passing the destination buffer to WriteL function of output stream

I played a mp3 file with bitrate of 24kbps,stero and with audio sample rate of 11 Khz by reading little by little from a file and passing it to CMdaAudioOutputStream. The setting I used for the stream was ESampleRate16000Hz Mono. The music played fine but was bit too slow may be because I was playing stereo. But the probelm is that the stream only supports ESampleRate16000Hz Mono and ESampleRate8000Hz Mono

If I specify any other sample rate the following line fails with NotSupported error. Stereo is not supported at all.

iOutputStream->SetAudioPropertiesL(iSetting.iSampleRate,
iSetting.iChannels);

why does it supports only two sample rate and thats too not stereo? This devices have inbuilt mp3 decoder. So why cant we adjust the settings. because if I am decoding mp3 of various sample rate I cant play them satisfactorily with just ESampleRate16000Hz Mono.

__________________
Prasanna Vignesh
MCPD | Web Developer

hi,

plz provide some clue whether we can use the in built codec in S60 2.1 phones through CMMFCodec. I have used it and it works but dont know how to configure the codec. Or do I need to use a third party software codec?

regards

__________________
Prasanna Vignesh
MCPD | Web Developer

Hi,

I am able to use the configureL function of the default mp3 codec but not to much success.
I used something like this,

RArray<TInt> configParams;

configParams.Append(1);
configParams.Append(0);
configParams.Append(0);
configParams.Append(0);
configParams.Append(0);
configParams.Append(0)

TUid codecId = TUid::Uid(KMmfUidControllerAudio);
iOCodec2->ConfigureL(codecId, (TDesC8&) configParams);

There are 6 parameters needed. If I give anything less than that it gives array out of bond index panic. Initially without configuring the decoder when i played a 11KHz mp3 song by decoding buffer by buffer and setting the output stream settings to 16KHz mono my song was too slow. But when I used the above setting the playing of song was bit too fast.
I dont know what these 6 parameters correspond to. I want to adjust these 6 parameters in such a way that it gives me 16KHz mono 16bit PCM sample for all my mp3 input. I havent come across any documentation about this.

regards,

The solution for your problem..

This should solve the problem of making audio being 'slow', but no guarentees.

Hope this helps

__________________
H2O

Without us, no one can survive..

It worked well.

regards,

__________________
Prasanna Vignesh
MCPD | Web Developer

Hi H2o...

How did you know how to configure the mp3 decoder? There's no documentation anywhere that I can find....