diff options
| author | Jamie Bullock <jamie@postlude.co.uk> | 2007-03-14 17:20:14 +0000 |
|---|---|---|
| committer | Jamie Bullock <jamie@postlude.co.uk> | 2007-03-14 17:20:14 +0000 |
| commit | 8c03bf4a4ec962659db170f3e5692413ac73e30a (patch) | |
| tree | f8912aedaee725faf3a3992abffc0b376e453175 /src/vector.c | |
| parent | ce919d7f2178c4dc71d121cc716480e311e756af (diff) | |
| download | LibXtract-8c03bf4a4ec962659db170f3e5692413ac73e30a.tar.gz LibXtract-8c03bf4a4ec962659db170f3e5692413ac73e30a.tar.bz2 LibXtract-8c03bf4a4ec962659db170f3e5692413ac73e30a.zip | |
Fixed bug in xtract_spectrum() FFTW_R2HC now interpreted correctly. Updated ChangeLog and AUTHORS files.
Diffstat (limited to 'src/vector.c')
| -rw-r--r-- | src/vector.c | 44 |
1 files changed, 29 insertions, 15 deletions
diff --git a/src/vector.c b/src/vector.c index b6b9308..2f54a3c 100644 --- a/src/vector.c +++ b/src/vector.c @@ -55,49 +55,63 @@ int xtract_spectrum(const float *data, const int N, const void *argv, float *res fftwf_execute(plan); switch(vector){ - case XTRACT_MAGNITUDE_SPECTRUM: - for(n = 0; n < M; n++){ - result[n] = sqrt(XTRACT_SQ(rfft[n]) + XTRACT_SQ(rfft[N - n])) / N; + +/* case XTRACT_MAGNITUDE_SPECTRUM: + for(n = 1; n < M; n++){ + result[n] = sqrt(XTRACT_SQ(rfft[n]) + + XTRACT_SQ(rfft[N - n - 1])) / N; result[M + n] = n * q; } break; +*/ case XTRACT_LOG_MAGNITUDE_SPECTRUM: - for(n = 0; n < M; n++){ - if ((temp = XTRACT_SQ(rfft[n]) + XTRACT_SQ(rfft[N - n])) > XTRACT_LOG_LIMIT) + for(n = 1; n < M; n++){ + if ((temp = XTRACT_SQ(rfft[n]) + + XTRACT_SQ(rfft[N - n - 1])) > XTRACT_LOG_LIMIT) temp = log(sqrt(temp) / N); else temp = XTRACT_LOG_LIMIT_DB; /*Normalise*/ - result[n] = (temp + XTRACT_DB_SCALE_OFFSET) / XTRACT_DB_SCALE_OFFSET; + result[n] = + (temp + XTRACT_DB_SCALE_OFFSET) / XTRACT_DB_SCALE_OFFSET; result[M + n] = n * q; } break; + case XTRACT_POWER_SPECTRUM: - for(n = 0; n < M; n++){ - result[n] = (XTRACT_SQ(rfft[n]) + XTRACT_SQ(rfft[N - n])) / NxN; + for(n = 1; n < M; n++){ + result[n] = (XTRACT_SQ(rfft[n]) + XTRACT_SQ(rfft[N - n - 1])) + / NxN; result[M + n] = n * q; } break; + case XTRACT_LOG_POWER_SPECTRUM: - for(n = 0; n < M; n++){ - if ((temp = XTRACT_SQ(rfft[n]) + XTRACT_SQ(rfft[N - n])) > XTRACT_LOG_LIMIT) + for(n = 1; n < M; n++){ + if ((temp = XTRACT_SQ(rfft[n]) + XTRACT_SQ(rfft[N - n - 1])) > + XTRACT_LOG_LIMIT) temp = log(temp / NxN); else temp = XTRACT_LOG_LIMIT_DB; - result[n] = (temp + XTRACT_DB_SCALE_OFFSET) / XTRACT_DB_SCALE_OFFSET; + result[n] = (temp + XTRACT_DB_SCALE_OFFSET) / + XTRACT_DB_SCALE_OFFSET; result[M + n] = n * q; } break; + default: /* MAGNITUDE_SPECTRUM */ - for(n = 0; n < M; n++){ - result[n] = sqrt(XTRACT_SQ(rfft[n]) + XTRACT_SQ(rfft[N - n])) / N; + for(n = 1; n < M; n++){ + result[n] = sqrt(XTRACT_SQ(rfft[n]) + + XTRACT_SQ(rfft[N - n - 1])) / N; result[M + n] = n * q; } break; } - /* result[0] = fabs(temp[0]) / N */ + /* Set the DC component to 0 */ + result[0] = result[M] = 0.f; + /* Set the Nyquist */ result[N] = q * M; fftwf_destroy_plan(plan); @@ -182,7 +196,7 @@ int xtract_dct(const float *data, const int N, const void *argv, float *result){ #else -int xtract_magnitude_spectrum(const float *data, const int N, const void *argv, float *result){ +int xtract_spectrum(const float *data, const int N, const void *argv, float *result){ XTRACT_NEEDS_FFTW; return XTRACT_NO_RESULT; |