This is clever, but I have also seen the lossless 1:2 compression of PCM wave data, which would give you the same benefit and keep the 8 bit waves. It works on the basis of derivations and Huffman coding, and obviously it is lossless, so it is not proven to be 1:2, but it usually is. I'd like to see this combined with your 4bit samples. :-)
A. ----- Original Message ----- From: "Stefan Drissen" <[EMAIL PROTECTED]> To: <sam-users@nvg.ntnu.no> Sent: Monday, March 17, 2003 9:23 AM Subject: RE: Mod music from Fred > Ged the mod player source and you should find the 'documentation'. If I recall correctly there is a check on the expected file length (number of patterns, number of samples, length of samples) and the actual file length - if the actual file length indicated that it was using 'half' samples then it was treated as such... > > The reason for chopping down to 4 bits was indeed 'compression' for the unused bits - note that the SAA(I can't even remember its number) actually only produced 3 bit samples... the lowest bit did nothing, so they could have been compressed even more... > > > Stefan > > > -----Original Message----- > From: Stuart Brady [mailto:[EMAIL PROTECTED] > Sent: Monday, March 17, 2003 1:35 AM > To: sam-users@nvg.ntnu.no > Subject: Re: Mod music from Fred > > > On Sun, Mar 16, 2003 at 11:31:31PM -0000, David wrote: > > ----- Original Message ----- > > From: "Stuart Brady" <[EMAIL PROTECTED]> > > To: <sam-users@nvg.ntnu.no> > > Sent: Sunday, March 16, 2003 10:38 PM > > Subject: Re: Mod music from Fred > > > > > Ahh, thanks! Does anybody know what was changed in the file formats to > > > allow for this? (I might as well write a converter for it...) > > > > As 4 bits of the data was chopped out - i think it will be easier to find > > the original if you want to play it at full quality. > > I had already done that - one of them wasn't quite so easy to find. > I'm more interested in converting in the other direction. From the sound > of it, writing a converter would be a trivial enough task. I'd also like > to check all of the modules to see which of them have any 4-bit samples. > > AFAICS, all I'd really need to know is where each sample is marked as > being a 4-bit sample, and which nibble comes first in the sample data. > > Cheers, > -- > Stuart Brady > >
