In a stream of FFT data, identify possible bins containing a CW signal. Run morse decoding instances on these.

See https://github.com/ag1le/morse-wip or https://github.com/magnemahre/morse-wip. This should be good enough, at least as a start. Must be made thread-safe, and probably be included as a separate library.

Need interface for recording decoded text, and control over which parts of the text have already been obtained and displayed on the GUI. Morse decoding thread should run by itself without intervention from the rest of the program until the signal has stopped, and continuously spew letters to a buffer? Should the number of morse decoding instances be limited to a predefined number, and then assign the instances to a new signal when it appears and de-assign instances when the signal stops? Connect decoded text to the signal bin, and not the decoder instance itself?

Initial tests showed that variations in signal amplitude causes some problems for the morse-wip decoding. This is either due to fading or intrinsic faults in the FFT transform. Identify preprocessing steps necessary for proper decoding.

GUI. Important elements:

1. Waterfall display displaying output from radio (see issue #4)
2. Show which FFT bins are being decoded on the waterfall display (see issue #3)
3. Show text output from each signal (see issue #1, #2), connected somehow to the waterfall display so it is intuitive which text string corresponds to which signal. Possibly identify each signal with a callsign? Show only callsign, and require the user to click on the signal to show the actual decoded text?

User should be able to click on a signal and see the entire decoded text stream.

Implement in Qt. Try to avoid a mess. It might make more sense to implement the GUI in the very end, after resolving the other issues.

Implement coherent interface against sound card (?) for obtaining signal input, transform to frequency space. Send to procedures implemented by issue #3.