[Forensics] Sacred Signal

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import numpy as np
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data = np.loadtxt("signal.log(4).txt")
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WINDOW = 20
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STD_THRESHOLD = 0.5
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segments = []
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i = 0
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while i <= len(data) - WINDOW:
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    window = data[i:i + WINDOW]
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    std_val = window.std()
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    if std_val < STD_THRESHOLD:
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        mean_val = window.mean()
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        segments.append({
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            "start": i,
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            "end": i + WINDOW - 1,
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            "mean": mean_val,
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            "std": std_val
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        })
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        i += WINDOW
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    else:
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        i += 1
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print("Perfect harmony segments:")
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for seg in segments:
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    print(
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        f"start={seg['start']:4d}, "
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        f"end={seg['end']:4d}, "
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        f"mean={seg['mean']:.6f}, "
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        f"std={seg['std']:.6f}"
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    )
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decoded = ''.join(chr(round(seg["mean"])) for seg in segments)
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print("\nDecoded text:")
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print(decoded)

WANLAI{2d248f4a162185c72d79abb98a568099}