X-Git-Url: https://git.rvb.name/rtl-433.git/blobdiff_plain/ca13278b24eb61443559bcb61e64627fba3d8823..6d15c6f967221af825cf84e3ed12b96c763b127b:/include/pulse_detect.h

diff --git a/include/pulse_detect.h b/include/pulse_detect.h
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+/**
+ * Pulse detection functions
+ *
+ * Copyright (C) 2015 Tommy Vestermark
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef INCLUDE_PULSE_DETECT_H_
+#define INCLUDE_PULSE_DETECT_H_
+
+#include <stdint.h>
+
+#define PD_MAX_PULSES 1200			// Maximum number of pulses before forcing End Of Package
+#define PD_MIN_PULSES 16			// Minimum number of pulses before declaring a proper package
+#define PD_MIN_PULSE_SAMPLES 10		// Minimum number of samples in a pulse for proper detection
+#define PD_MIN_GAP_MS 10			// Minimum gap size in milliseconds to exceed to declare End Of Package
+#define PD_MAX_GAP_MS 100			// Maximum gap size in milliseconds to exceed to declare End Of Package
+#define PD_MAX_GAP_RATIO 10			// Ratio gap/pulse width to exceed to declare End Of Package (heuristic)
+#define PD_MAX_PULSE_MS 100			// Pulse width in ms to exceed to declare End Of Package (e.g. for non OOK packages)
+
+/// Data for a compact representation of generic pulse train
+typedef struct {
+	unsigned int num_pulses;
+	int pulse[PD_MAX_PULSES];	// Contains width of a pulse	(high)
+	int gap[PD_MAX_PULSES];		// Width of gaps between pulses (low)
+	int ook_low_estimate;		// Estimate for the OOK low level (base noise level) at beginning of package
+	int ook_high_estimate;		// Estimate for the OOK high level at end of package
+	int fsk_f1_est;				// Estimate for the F1 frequency for FSK
+	int fsk_f2_est;				// Estimate for the F2 frequency for FSK
+} pulse_data_t;
+
+
+/// Clear the content of a pulse_data_t structure
+void pulse_data_clear(pulse_data_t *data);		// Clear the struct
+
+/// Print the content of a pulse_data_t structure (for debug)
+void pulse_data_print(const pulse_data_t *data);
+
+
+/// Demodulate On/Off Keying (OOK) and Frequency Shift Keying (FSK) from an envelope signal
+///
+/// Function is stateful and can be called with chunks of input data
+/// @param envelope_data: Samples with amplitude envelope of carrier 
+/// @param fm_data: Samples with frequency offset from center frequency
+/// @param len: Number of samples in input buffers
+/// @param samp_rate: Sample rate in samples per second
+/// @param *pulses: Will return a pulse_data_t structure
+/// @param *fsk_pulses: Will return a pulse_data_t structure for FSK demodulated data
+/// @return 0 if all input sample data is processed
+/// @return 1 if OOK package is detected (but all sample data is still not completely processed)
+/// @return 2 if FSK package is detected (but all sample data is still not completely processed)
+int pulse_detect_package(const int16_t *envelope_data, const int16_t *fm_data, int len, int16_t level_limit, uint32_t samp_rate, pulse_data_t *pulses, pulse_data_t *fsk_pulses);
+
+
+/// Analyze and print result
+void pulse_analyzer(pulse_data_t *data, uint32_t samp_rate);
+
+
+#endif /* INCLUDE_PULSE_DETECT_H_ */