@echo off
cls
REM Samples submitted by trixter@oldskool.org (Jim Leonard), contact me
REM for additional details if necessary.

echo All of these files were created by the VEDIT2.EXE program, which
echo unfortunatly requires EGA, a mouse, and most importantly a very specific
echo revision of Sound Blaster called a Sound Blaster Pro rev 2 board.  The
echo version of software provided here is hard-coded to IRQ 2, port 220h, and
echo DMA 1, for those attempting to get it running under emulation.  The Sound
echo Blaster Pro DSP revision I unfortunately don't remember, so you'll have to
echo patch the program to just bypass that check and hope it doesn't crash.
echo
echo The compression scheme was called "Creative ADPCM" back in the late
echo 1980s/early 1990s, and the 8-bit scheme has, to my knowledge, never been
echo reverse-engineered.  (The 16-bit scheme has.)  ADPCM samples can be played
echo back in hardware by the DSP without any CPU usage, but creating them
echo remains a mystery.  The samples provided have a rate of 11025Hz, because
echo the Sound Blaster series of cards' DSPs were only fast enough to play back
echo compressed samples at a rate of 12KHz, no more.  (You can create 22KHz
echo compressed samples but they will play back at 12KHz.)
echo
echo If anyone reverse-engineers the scheme, PLEASE let me know as I am very
echo interested in 8-bit PCM compression schemes and have always wondered how
echo this one works.  BTW, yes, the 2-bit ("4:1") scheme sounds pretty bad :)

echo To play all of the sound samples,
pause

echo Playing Taxiride sample, 8-bit unsigned PCM (uncompressed)
vplay TAXI8BIT.VOC
echo Playing Taxiride sample, 4-bit ("2:1") compressed
vplay TAXI4BIT.VOC
echo Playing Taxiride sample, 3-bit ("3:1") compressed
vplay TAXI3BIT.VOC
echo Playing Taxiride sample, 2-bit ("4:1") compressed
vplay TAXI2BIT.VOC

echo Playing BBC sample, 8-bit unsigned PCM (uncompressed)
vplay BBC_8BIT.VOC
echo Playing BBC sample, 4-bit ("2:1") compressed
vplay BBC_2BIT.VOC
echo Playing BBC sample, 3-bit ("3:1") compressed
vplay BBC_3BIT.VOC
echo Playing BBC sample, 2-bit ("4:1") compressed
vplay BBC_4BIT.VOC