add fmdsp fft analyzer

1 files changed, 35 insertions, 0 deletions

diff --git a/fft/fft.h b/fft/fft.h
new file mode 100644
index 0000000..b446739
--- /dev/null
+++ b/fft/fft.h
@@ -0,0 +1,35 @@
+#ifndef MYON_FMPLAYER_FFT_FFT_H_INCLUDED
+#define MYON_FMPLAYER_FFT_FFT_H_INCLUDED
+
+#include <stdint.h>
+
+enum {
+  FFTLEN = 8192,
+  FFTDISPLEN = 70,
+};
+
+struct fmplayer_fft_data {
+  int16_t buf[FFTLEN];
+  unsigned ind;
+};
+
+struct fmplayer_fft_input_data {
+  struct fmplayer_fft_data fdata;
+  int16_t work[FFTLEN];
+  double dwork[FFTLEN];
+  float fwork[FFTLEN*2];
+};
+
+struct fmplayer_fft_disp_data {
+  // 0 - 31
+  // 4 per 6db
+  uint8_t buf[FFTDISPLEN];
+};
+
+void fft_init_table(void);
+
+void fft_write(struct fmplayer_fft_data *data, const int16_t *buf, unsigned len);
+
+void fft_calc(struct fmplayer_fft_disp_data *ddata, struct fmplayer_fft_input_data *idata);
+
+#endif // MYON_FMPLAYER_FFT_FFT_H_INCLUDED