HTML Canvas/WebSockets Waterfall

This is a small experiment to create a waterfall plot with HTML Canvas and WebSockets to stream live FFT data from an SDR:

.. image:: img/waterfall.png

spectrum.js contains the main JavaScript source code for the plot, while colormap.js contains colormaps generated using make_colormap.py.

index.html, style.css, script.js contain an example page that receives FFT data on a WebSocket and plots it on the waterfall plot.

server.py contains a example Bottle <https://bottlepy.org/docs/dev/> and gevent-websocket <https://pypi.org/project/gevent-websocket/> server that broadcasts FFT data to connected clients. The FFT data is generated using GNU radio <https://www.gnuradio.org/>_ using a USRP but it should be fairly easy to change it to a different SDR.