We have an application that uses a sub band ADPCM (G.722) coder and decoder. Our goal is data reduction with good quality, minimal computation overhead and extended speech bandwidth. We chose G.722 because we didn't want to reinvent the wheel and it appeared to be a good candidate. We have several examples in C (Embree) and asm (ADI 21xx) and none of them give answers that make sense (at least to us). For example, if we input a 4K sequence (.5,0,-.5,0), we get nothing similar out. I understand that there is some kind of test sequence available that we could use as a sanity check. I don't have a copy of the standard. Does anyone have this sequence? Any suggestions? -- Al Clark Danville Signal Processing, Inc. -------------------------------------------------------------------- comp.dsp conference July 28 - Aug 1, 2004 details at http://www.danvillesignal.com/index.php?id=compdsp email: compdsp@danvillesignal.com Who says you can't teach an old dog a new DSP trick?
G.722 ADPCM Help
Started by ●June 30, 2004
Reply by ●June 30, 20042004-06-30
Al Clark wrote:> We have an application that uses a sub band ADPCM (G.722) coder and > decoder. Our goal is data reduction with good quality, minimal computation > overhead and extended speech bandwidth. We chose G.722 because we didn't > want to reinvent the wheel and it appeared to be a good candidate. > > We have several examples in C (Embree) and asm (ADI 21xx) and none of them > give answers that make sense (at least to us). > For example, if we input a 4K sequence (.5,0,-.5,0), we get nothing > similar out. > > I understand that there is some kind of test sequence available that we > could use as a sanity check. I don't have a copy of the standard. Does > anyone have this sequence? > > Any suggestions?You can get the test documentation and sequences from www.itu.int for a small fee of 52 CHF. You want to look for G.722 Appendix II. Regards -- Adrian Hey
Reply by ●June 30, 20042004-06-30
Adrian Hey <ahey@NoSpicedHam.iee.org> wrote in news:arqdnSKd- aMY237dRVn_iw@nildram.net:> www.itu.intThanks Adrian, Actually, I found out that you can download three publications for free. -- Al Clark Danville Signal Processing, Inc. -------------------------------------------------------------------- comp.dsp conference July 28 - Aug 1, 2004 details at http://www.danvillesignal.com/index.php?id=compdsp email: compdsp@danvillesignal.com Who says you can't teach an old dog a new DSP trick?
