1 SpanDSP is a library of DSP functions for telephony, in the 8000
2 sample per second world of E1s, T1s, and higher order PCM channels.
3 It contains low level functions, such as basic filters. It also
4 contains higher level functions, such as cadenced supervisory tone
5 detection, and a complete software FAX machine. The software has
6 been designed to avoid intellectual property issues, using mature
7 techniques where all relevant patents have expired. See the file
8 DueDiligence for important information about these intellectual