mirror of
https://github.com/cjfranko/NTP-Timeturner.git
synced 2025-11-08 18:32:02 +00:00
71 lines
2.3 KiB
Python
71 lines
2.3 KiB
Python
#!/usr/bin/env python3
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"""
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ltc_probe.py
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Improved LTC-like signal probe — detects pulse duration patterns
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consistent with bi-phase mark code used in SMPTE LTC.
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"""
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import numpy as np
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import sounddevice as sd
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DURATION = 1.0 # seconds
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SAMPLERATE = 48000
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CHANNELS = 1
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MIN_EDGES = 1000 # sanity threshold
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def detect_rising_edges(signal):
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# signal: flattened 1D numpy array
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above_zero = signal > 0
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edges = np.where(np.logical_and(~above_zero[:-1], above_zero[1:]))[0]
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return edges
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def analyze_pulse_durations(edges, samplerate):
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durations = np.diff(edges) / samplerate # in seconds
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if len(durations) == 0:
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return None
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short_pulse_threshold = np.median(durations) * 1.5
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short = durations[durations <= short_pulse_threshold]
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long = durations[durations > short_pulse_threshold]
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return {
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"count": len(durations),
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"avg_width_ms": np.mean(durations) * 1000,
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"short_pulses": len(short),
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"long_pulses": len(long),
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"short_pct": (len(short) / len(durations)) * 100,
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"long_pct": (len(long) / len(durations)) * 100
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}
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def verdict(pulse_data):
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if pulse_data is None or pulse_data["count"] < MIN_EDGES:
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return "❌ No signal or not enough pulses"
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elif 30 < pulse_data["short_pct"] < 70:
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return f"✅ LTC-like bi-phase signal detected ({pulse_data['count']} pulses)"
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else:
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return f"⚠️ Inconsistent signal — may be non-LTC or noisy"
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def main():
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print("🔍 Capturing 1 second of audio for LTC probing...")
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audio = sd.rec(int(DURATION * SAMPLERATE), samplerate=SAMPLERATE, channels=CHANNELS, dtype='float32')
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sd.wait()
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signal = audio.flatten()
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edges = detect_rising_edges(signal)
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pulse_data = analyze_pulse_durations(edges, SAMPLERATE)
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print(f"\n📊 Pulse Analysis:")
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if pulse_data:
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print(f" Total pulses: {pulse_data['count']}")
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print(f" Avg pulse width: {pulse_data['avg_width_ms']:.2f} ms")
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print(f" Short pulses: {pulse_data['short_pulses']} ({pulse_data['short_pct']:.1f}%)")
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print(f" Long pulses: {pulse_data['long_pulses']} ({pulse_data['long_pct']:.1f}%)")
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else:
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print(" Not enough data to analyze.")
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print("\n🧭 Verdict:")
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print(" ", verdict(pulse_data))
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if __name__ == "__main__":
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main()
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