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| author | Jamie Bullock <jamie@jamiebullock.com> | 2013-01-09 12:54:28 +0000 |
|---|---|---|
| committer | Jamie Bullock <jamie@jamiebullock.com> | 2013-01-09 12:54:28 +0000 |
| commit | 0adbb0bfcd92347fdcbd235cf1e2ef858de974ef (patch) | |
| tree | 40947db1a33cdd0e62de8197b25c15f9c309870c /src/vector.c | |
| parent | c277634b13117e721e43f34a09cafb93c725fa3f (diff) | |
| download | LibXtract-0adbb0bfcd92347fdcbd235cf1e2ef858de974ef.tar.gz LibXtract-0adbb0bfcd92347fdcbd235cf1e2ef858de974ef.tar.bz2 LibXtract-0adbb0bfcd92347fdcbd235cf1e2ef858de974ef.zip | |
run FFT in place on the data vector
Diffstat (limited to 'src/vector.c')
| -rw-r--r-- | src/vector.c | 24 |
1 files changed, 7 insertions, 17 deletions
diff --git a/src/vector.c b/src/vector.c index 5639374..7db8695 100644 --- a/src/vector.c +++ b/src/vector.c @@ -45,19 +45,11 @@ int xtract_spectrum(const double *data, const int N, const void *argv, double *r double NxN = XTRACT_SQ(N); double *marker = NULL; size_t bytes = N * sizeof(double); - double *rfft = NULL; unsigned int n = 0; unsigned int m = 0; unsigned int nx2 = 0; unsigned int M = N >> 1; - rfft = (double *)malloc(bytes); - //memcpy(rfft, data, bytes); - - for(n = 0; n < N; ++n){ - rfft[n] = (double)data[n]; - } - q = *(double *)argv; vector = (int)*((double *)argv+1); withDC = (int)*((double *)argv+2); @@ -74,10 +66,10 @@ int xtract_spectrum(const double *data, const int N, const void *argv, double *r } /* ooura is in-place - * the output format seems to be + * the output format is * a[0] - DC, a[1] - nyquist, a[2...N-1] - remaining bins */ - rdft(N, 1, rfft, ooura_data_spectrum.ooura_ip, + rdft(N, 1, data, ooura_data_spectrum.ooura_ip, ooura_data_spectrum.ooura_w); switch(vector) @@ -91,7 +83,7 @@ int xtract_spectrum(const double *data, const int N, const void *argv, double *r continue; } nx2 = n * 2; - temp = XTRACT_SQ(rfft[nx2]) + XTRACT_SQ(rfft[nx2+1]); + temp = XTRACT_SQ(data[nx2]) + XTRACT_SQ(data[nx2+1]); if (temp > XTRACT_LOG_LIMIT) { temp = log(sqrt(temp) / (double)N); @@ -117,7 +109,7 @@ int xtract_spectrum(const double *data, const int N, const void *argv, double *r { ++n; } - result[m] = (XTRACT_SQ(rfft[n]) + XTRACT_SQ(rfft[N - n])) / NxN; + result[m] = (XTRACT_SQ(data[n]) + XTRACT_SQ(data[N - n])) / NxN; XTRACT_SET_FREQUENCY; XTRACT_GET_MAX; } @@ -130,7 +122,7 @@ int xtract_spectrum(const double *data, const int N, const void *argv, double *r { ++n; } - if ((temp = XTRACT_SQ(rfft[n]) + XTRACT_SQ(rfft[N - n])) > + if ((temp = XTRACT_SQ(data[n]) + XTRACT_SQ(data[N - n])) > XTRACT_LOG_LIMIT) temp = log(temp / NxN); else @@ -159,8 +151,8 @@ int xtract_spectrum(const double *data, const int N, const void *argv, double *r ++n; } - *marker = (double)(sqrt(XTRACT_SQ(rfft[n*2]) + - XTRACT_SQ(rfft[n*2+1])) / (double)N); + *marker = (double)(sqrt(XTRACT_SQ(data[n*2]) + + XTRACT_SQ(data[n*2+1])) / (double)N); XTRACT_SET_FREQUENCY; XTRACT_GET_MAX; @@ -175,8 +167,6 @@ int xtract_spectrum(const double *data, const int N, const void *argv, double *r result[n] /= max; } - free(rfft); - return XTRACT_SUCCESS; } |