78 lines
1.4 KiB
C
78 lines
1.4 KiB
C
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/*
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* fsk.h
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*
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* Copyright (C) 2011 Kamal Mostafa <kamal@whence.com>
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*
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* NO LICENSE HAS BEEN SPECIFIED OR GRANTED FOR THIS WORK.
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*
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*/
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#define USE_FFT // leave this enabled; its presently the only choice
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#ifdef USE_FFT
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#include <fftw3.h>
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#endif
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typedef struct fsk_plan fsk_plan;
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struct fsk_plan {
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float sample_rate;
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float f_mark;
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float f_space;
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float filter_bw;
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unsigned int n_data_bits;
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unsigned int n_frame_bits;
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#ifdef USE_FFT
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int fftsize;
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unsigned int nbands;
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unsigned int band_width;
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unsigned int b_mark;
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unsigned int b_space;
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fftwf_plan fftplan;
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float *fftin;
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fftwf_complex *fftout;
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#endif
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};
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fsk_plan *
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fsk_plan_new(
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float sample_rate,
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float f_mark,
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float f_space,
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float filter_bw,
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unsigned int n_data_bits
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);
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void
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fsk_plan_destroy( fsk_plan *fskp );
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/* returns confidence value [0.0 to 1.0] */
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float
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fsk_find_frame( fsk_plan *fskp, float *samples, unsigned int frame_nsamples,
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unsigned int try_max_nsamples,
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unsigned int try_step_nsamples,
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unsigned int *bits_outp,
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unsigned int *frame_start_outp
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);
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int
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fsk_detect_carrier(fsk_plan *fskp, float *samples, unsigned int nsamples,
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float min_mag_threshold );
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void
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fsk_set_tones_by_bandshift( fsk_plan *fskp, unsigned int b_mark, int b_shift );
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// FIXME move this?:
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//#define FSK_DEBUG
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#ifdef FSK_DEBUG
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# define debug_log(format, args...) fprintf(stderr, format, ## args)
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#else
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# define debug_log(format, args...)
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#endif
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