Questions on sound for Dreamcast

[Protofall]

I've played around with sound on the DC in the past, but its still very foreign to me. I've got some questions about some areas I'm not familiar with.
1. I know the snd_sfx library can only take 16-bit uncompressed or 4-bit compressed sound effects, but I can't remember what the max length for those files are. I just *know* I've seen a post somewhere on these forums that states exactly how many seconds they go for, but I have no idea which page said it and how to find it again
2. What native music formats can the Sound-cpu take? I know there's libraries for oog, mp3 (Which is licensed so I shouldn't use), s3m and then there's CDDA but I'm curious about the native format/s. Is it 32-bit sound or something else? I'm a complete sound noob so this might be a dumb question.
3. Is it possible to stream oog/mp3/s3m audio like you can with CDDA so you can play a long song without it all just sitting in RAM? I'm not sure if the libraries/ports allow for that.

Thanks in advance

[Ayla]

I'll answer what I can:

2. Either 16-bit raw PCM, or 4-bit raw ADPCM (the Yamaha variant).

3. CDDA has a direct path from the GD-ROM block to the sound hardware. For everything else, including WAV files on the disc, you need to copy them to RAM and steam them to the sound firmware.

[ThePerfectK]

Anyone got a cdda demo? How does one burn the disc for cdda audio tracks?

[Protofall]

I'll answer what I can:

2. Either 16-bit raw PCM, or 4-bit raw ADPCM (the Yamaha variant).

3. CDDA has a direct path from the GD-ROM block to the sound hardware. For everything else, including WAV files on the disc, you need to copy them to RAM and steam them to the sound firmware.

Thanks for that info

Anyone got a cdda demo? How does one burn the disc for cdda audio tracks?

KOS does come with a CDDA demo, but it isn't exactly complete. Once you build the elf and 1st_read.bin you need to make a special iso and then use a program like MDS4DC to make a Dreamcast image. I believe DEMUL can run .mds files and maybe some other emulators too. Right now cdi4dc doesn't have cdda support. You can find instruction on using MDS4DC with CDDA here https://github.com/Kazade/img4dc/tree/master/mds4dc/doc

[mrneo240]

Ya, I wrote the streaming sample for aldc which happily loops and streams a 60mb WAV file from disc forever.

I still haven't been able to find a way to nicely synthesize sound without Kos, most of my stuff is just screeteches