gbadev.org forum archive

This is a read-only mirror of the content originally found on forum.gbadev.org (now offline), salvaged from Wayback machine copies. A new forum can be found here.

DS development > Calculate optimum ADPCM values?

#174343 - Ruben - Tue Jun 01, 2010 11:53 am

Hi.

So I'm just making my converter as best as I can before FINALLY adding support for libnds by making use of sub-functions rather than calling the actual thing [like FIFO/IRQ stuff] and, while my samples sound OK at the moment with ADPCM [first sample = 0, first index = 0], they do tend to get a fair amount of noise. I noticed that commercial games [which appear to have less noise] tend to have start sample values and start index values that are not 0 which is the case with most homebrew audio so... Does anyone know how to calculate an optimum sample start + index values?