Usage: ggmorse-to-file [-fN] -[wN] [-vN] [-sN]
    -fN - frequency of the generated signal, N in [100, sampleRate/2], (default: 550)
    -wN - speed of the transmission in words-per-minute, N in [5, 140], (default: 25)
    -vN - output volume, N in (0, 100], (default: 50)
    -sN - output sample rate, N in [4000, 96000], (default: 4000)

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