The Challenge

The challenge gives a WAV audio file called comunicazione.wav. Playing it reveals the classic dit-dah pattern of Morse code. Manual transcription is possible but tedious.

Approach

The morse-audio-decoder Python library (pip install morse-audio-decoder) handles the entire pipeline: it reads the WAV file, detects the signal timing, segments the dots and dashes, and returns the decoded text. The output is the flag content — wrapping it in flag{...} gives the full flag.

Solution

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from morse_audio_decoder.morse import MorseCode
morse_code = MorseCode.from_wavfile("comunicazione.wav")
out = morse_code.decode()
print("flag{" + out + "}")

Three lines. from_wavfile loads and analyses the WAV. .decode() converts the signal to text. The result is printed inside the flag format.

What I Learned

Audio Morse challenges do not require manual listening. morse-audio-decoder automates the entire signal-to-text pipeline as long as the recording is clean enough. For noisy recordings, Audacity’s spectrogram view or the scipy short-time Fourier transform can help isolate the Morse carrier frequency before passing to the decoder.