This is a spectrum view and waterfall plot, all in the terminal!
The spectrum view is done by printing braille characters à la drawille. This gives twice the horizontal resolution and four times the vertical resolution of the terminal cells. The waterfall is done by plotting the "upper half block" character (▀) with a different background and foreground color, giving twice the vertical resolution of the cells. You'll need a terminal with 256-color support for the colors to work properly.
The FFTs are done with the RustFFT library, and the terminal UI is done using the rustty library.
Currently, this project only works with the HackRF. Support for other radios should be coming soon.