Homebrew Streaming music with libnds

[corenting]

Hello,

I'm working on an AndroDaft (iDaft clone with more songs) port for the DS using libnds + nflib.

But I have a problem...

The background music of "Harder Better Faster Stronger" is too big to fit in the memory
So, I wanted to stream it from the NitroFS using MaxMod. I saw that there is a documentation (on maxmod.org) and one example (in devkitpro's examples). But I don't know how to convert sounds for MaxMod using mmutils. And I don't know if MaxMod will create conflicts with nflib and the sound functions it provides. So if someone can help me with this it will be great.

 

[sulfyr]

Hi,

You could convert the music into a raw format like 22050hz 16-bit stereo and then stream it manually.

Open the file from nitrofs and create a stream:

file = fopen("somesong.raw","rb");

mm_stream mystream;
mystream.buffer_length = 1024;
mystream.callback = stream;
mystream.timerÂÂ= MM_TIMER0;
mystream.manual = true;
mystream.sampling_rate = 22050;
mystream.format = MM_STREAM_16BIT_STEREO;
mmStreamOpen(&mystream);

while(1){
ÂÂÂÂ//Read data from the file to the buffer
ÂÂÂÂmmStreamUpdate();
ÂÂÂÂ
ÂÂÂÂ//Do other stuff
}

When the music is stored raw you can just read it directly to the audio buffer:

mm_word stream(mm_word length, mm_addr dest, mm_stream_formats format){ÂÂÂÂ
ÂÂÂÂsize_t samplesize;
ÂÂÂÂswitch(format){
ÂÂÂÂÂÂÂÂcase MM_STREAM_8BIT_MONO: samplesize = 1; break;
ÂÂÂÂÂÂÂÂcase MM_STREAM_8BIT_STEREO: samplesize = 2; break;
ÂÂÂÂÂÂÂÂcase MM_STREAM_16BIT_MONO: samplesize = 2; break;
ÂÂÂÂÂÂÂÂcase MM_STREAM_16BIT_STEREO: samplesize = 4; break;
ÂÂÂÂ}
ÂÂÂÂ
ÂÂÂÂint res = fread(dest,samplesize,length,file);
ÂÂÂÂif(res){
ÂÂÂÂÂÂÂÂlength = res;
ÂÂÂÂ} else {
ÂÂÂÂÂÂÂÂ//End of file
ÂÂÂÂÂÂÂÂlength = 0;
ÂÂÂÂ}
ÂÂÂÂ
ÂÂÂÂreturn length; //Return the number of samples read
}

I have created a small example that streams music from nitrofs and plays some soundeffects from memory. AndroDaft.nds, source.zip

Hope this helps

 

[corenting]

Thanks you very much for this useful answer. I will try to apply it to my homebrew... Expect a demo soon.

EDIT : It's a bit complicated for me to integrate this in my code... So it will take longer. I'm also looking with other librairies (I know I can do this with PAlib, but I don't want to use PAlib for this project).