Hi Mychaela,
aside from spandsp, there's also the long-abandoned linmodem
project by Fabrice Bellard. I made it build under [then] current
linux/gcc a few years back, see
https://gitea.osmocom.org/retronetworking/linmodem
and there's also some related issues in our redmine at
https://osmocom.org/projects/linmodem/issues
linmodem is probably less complete or even field-proven than spandsp. However, it
does have some nice bits like visualization (via X11) as well as a channel simulator
for the telephone line so you can simulate the performance of modems via that channel
simulator.
--
- Harald Welte <laforge(a)gnumonks.org>
https://laforge.gnumonks.org/
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