tscott@westford.ccur.com (Tom Scott) (08/02/90)
I'm interested in an algorithm for converting between PCM (pulse code modulation) and ADPCM (adaptive differential pulse code modulation). The system I'm using has a commercial chip, that I believe is made by Toshiba, to digitize and encode voice and I need to know the algorithm so that I can write software to decode its output for voice analysis. My guess is that the chip implements CCITT's standards 32-kb/s ADPCM algorithm but don't know what this algorithm is. Help is appreciated. Tom Scott tscott@westford.ccur.com
chip@chinacat.Unicom.COM (Chip Rosenthal) (08/02/90)
In article <36771@masscomp.ccur.com> tscott@westford.ccur.com (Tom Scott) writes: >My guess is that the chip implements CCITT's standards 32-kb/s ADPCM >algorithm but don't know what this algorithm is. Help is appreciated. If the Toshiba chip does indeed implement the standard ADPCM algorithm, it would be specified in G.721. (BTW...even if it is G.721, you need to know which one -- there were two.) You can get the CCITT fasciles through a place like Omnicom, but they are expensive. A good engineering library should have them as well. -- Chip Rosenthal | You aren't some icon carved out chip@chinacat.Unicom.COM | of soap, sent down here to clean Unicom Systems Development, 512-482-8260 | up my reputation. -John Hiatt