dmb@wam.umd.edu (David M. Baggett) (05/09/91)
In article <1991May8.055008.2758@isc.rit.edu> drp9500@isc.rit.edu (D.R. Paradis ) writes: >sound files with the .au extender are Sun Audio files. > >As of now I cannot figure how to convert them into ANY format that the >ST can handle. :-( The Atari uses the same sample data format as the Mac, so if there's a way to convert Sparcstation samples to Mac format, you can use them (the data forks) on the Atari as well. Could some kind Mac wizard point me to a Sparc->Mac sample converter? Given source for such a utility I could write an ST version and make many Atari owners happy. (Or at least happier.) Thanks, Dave Baggett dmb%wam.umd.edu@uunet.uu.net
dave@msb.com (Dave Lockwood) (05/13/91)
Converting the .au samples is a snap. According to the audio man page on my system, the Sun audio data is 8 bit signed volume values. The high order bit is a sign bit. If set, the volume is positive (1's compliment), and if the sign bit is 0, the value is a negative volume (also 1's compliment). In a C program reading the Sun audio data, stick this code in the middle of the conversion loop: if(value & 128) value = 128 + (127 - (value & 127)); See...baby food. If the sign bit isn't set, no conversion need be done. The resulting output is a volume level from 0 to 255 with 128 being the zero crossing. Multiply the result by a fraction if you want to change the volume before output. I'll leave the headers up to you. I never monkeyed with that (the man page is rather cryptic about this), and besides, you wouldn't want me to take ALL the fun out of it, would you? ;-) -- A tool that isn't sharp enough to cut | dave@msb.com (Dave Lockwood) you badly isn't sharp enough to use. | UUCP: ...!uupsi!mpoint!dave However, the sharp edges should *NOT* be | Sysop of Meetpoint Station BBS on the handle. | cat flames | mail santa@north.pole