Stuttering with OGG or MP3

MacScumm · Post by **MacScumm** » Sat Jan 03, 2009 5:57 pm

Hi,

I experience stuttering of the music in all the ScummVM games that use OGGs or MP3s as soundtrack. Is that common behaviour for the Symbian version? All other sound effects work fine.

Cheers,
Mac

Anotherguest · Post by **Anotherguest** » Mon Jan 05, 2009 4:05 pm

Keep the bitrates LOW in order to avoid stuttering, i.e max bitrate of 56kbps.

MacScumm · Post by **MacScumm** » Mon Jan 05, 2009 8:04 pm

Anotherguest wrote:Keep the bitrates LOW in order to avoid stuttering, i.e max bitrate of 56kbps.

Thanks. That removed the stuttering in Indy3 and Loom pretty good. For Monkey Island it seemed I had to go even lower - something around 40 kbps still had some slight skips in the music but was acceptable.
But it's not just the bitrate. Since OGG decoding is obviously a lot more demanding, I had to go with MP3, which is still ok at this bitrate considering the speaker of the phone.

Cheers,
Mac

Freddo · Post by **Freddo** » Tue Mar 10, 2009 8:57 am

Anotherguest, how hard would it be to let the built in mp3 codec (MMF) deal with the mp3 decoding & stuff instead of the CPU?

Anotherguest · Post by **Anotherguest** » Tue Mar 10, 2009 10:36 am

Not very easy Usually you have audiotracks mixed with other sounds (like sfx + music for example) and Symbian does not support that. So first I would have to setup a conversion mechanism that converts a piece of streamed MP3 track to PCM, that is mixed with other bits and pieces.

And remember that both OGG and madlib contains ARM assembly optimizations.

Try defragging your memorycards. Actually I think its the fileaccess causing most of the lag, not the actualplayback. ScummVM has a fixed size buffer it decodes from,the lowerbitrate, the longer playback time the buffer will hold. Each fileread might cause a "lag" or skip.

Fileaccess varies very much on different Symbian phones and also depends on the memorycard used. Try a highspeed card, try a smaller card, try a larger card, try putting the game into internal memory etc.