Playing ADPCM sounds on Amiga… November 5, 2006Posted by winden in coding, demoscene.
So yesterday I finally started to code an ADPCM sound player, since upon scrounging google I didn’t really manage to find any public 680×0 sources to do the playing like for example can be done with players like “the player 6.1” are not turned up when searched for, so maybe there are really free-to-use players… but anyways, armed with a tutorial from jurassic pack 14 by scicco/scarab about how to drive the Amiga to make a buffered sound loop, I dove into the hardware hacking and a few hours later I had a 16bit uncrompressed wav sounding as a 8bit realtime dithered wave on the Amy.
Fun started when I started trying to covert the standards-provided reference sourcecode for IMA-ADPCM into a 680×0 routine… and today after a few more hours it’s starting to sound somewhat like the original but with pops and clcks (which the original roxette song didn’t have ;)… so I think I may be nearing the first version with proper sound :)
What I’ve also detected is that ADPCM decoding will be difficult to optimise regarding cpu pairing and the like… so after I have it working maybe I’ll have to spend some time making my own compressed format which could be decoded with less serial dependencies.
Off to code some more…