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

The library is licenced under the LGPL 2.1 licence. The test suite, and some support programs are licenced under the GPL 2 licence. The full text of these licences can be found in the file COPYING.

spandsp depends on various other packages for various tasks. Most of these dependencies relate to building the test suite.

libtiff (and libtiff-devel on most Linux distributions) is required to build the spandsp library.

libaudiofile (and libaudiofile-devel) is required to build the test suite fftw (and fftw-devel) is required to build the test suite. Version 2 or 3 of FFTW may be used. Spandsp adapts to the differences between them.

fltk (and fltk-devel), Fl_Cartesian and Fl_Audio_Meter are required to build the test suite with GUI interfaces for some of the tests. The tests will build without these packages, but the GUI features will not be available. Fl_Cartesian and Fl_Audio_Meter can be downloaded from GitHub at https://github.com/madscientist42/spandsp-fltk-libs.

Steve Underwood [email protected]

(New maintainer...) Frank Earl [email protected]