Quisk is SDR software that can be used with HiQSDR hardware, SDR-IQ and SoftRock. It runs on Windows and Linux. See
james.ahlstrom.name. I use Quisk in my homebrew station in New Jersey.
Quisk can handle external digital mode programs like Fldigi and FreeDV. But now, Quisk has freedv built in. To use it, you just press the FDV button instead of USB, and talk. I am hoping this will get a lot more people into digital voice.
The implementation uses the API in freedv_api.c and freedv_api.h in the codec-dev src subdirectory. All things considered, the implementation was easy. The external FreeDV program provided by
freedv.org is not used. I will be happy to provide details if anyone is interested.