From: Paul Brossier <piem@piem.org>
Date: Tue, 16 Feb 2016 20:50:08 +0000 (+0100)
Subject: src/spectral/mfcc.c: swap dct_coeffs matrix to prepare for fmat_vecmul
X-Git-Tag: 0.4.4~300^2~331
X-Git-Url: https://git.aubio.org/?a=commitdiff_plain;h=c02a1cc58a1b936059d7acb72c6e070b6406ec75;p=aubio.git

src/spectral/mfcc.c: swap dct_coeffs matrix to prepare for fmat_vecmul
---

diff --git a/src/spectral/mfcc.c b/src/spectral/mfcc.c
index a0e35bed..ed998117 100644
--- a/src/spectral/mfcc.c
+++ b/src/spectral/mfcc.c
@@ -67,17 +67,17 @@ new_aubio_mfcc (uint_t win_s, uint_t n_filters, uint_t n_coefs,
   /* allocating buffers */
   mfcc->in_dct = new_fvec (n_filters);
 
-  mfcc->dct_coeffs = new_fmat (n_filters, n_coefs);
+  mfcc->dct_coeffs = new_fmat (n_coefs, n_filters);
 
-  /* compute DCT transform dct_coeffs[i][j] as
+  /* compute DCT transform dct_coeffs[j][i] as
      cos ( j * (i+.5) * PI / n_filters ) */
   scaling = 1. / SQRT (n_filters / 2.);
   for (i = 0; i < n_filters; i++) {
     for (j = 0; j < n_coefs; j++) {
-      mfcc->dct_coeffs->data[i][j] =
+      mfcc->dct_coeffs->data[j][i] =
           scaling * COS (j * (i + 0.5) * PI / n_filters);
     }
-    mfcc->dct_coeffs->data[i][0] *= SQRT (2.) / 2.;
+    mfcc->dct_coeffs->data[0][i] *= SQRT (2.) / 2.;
   }
 
   return mfcc;
@@ -120,7 +120,7 @@ aubio_mfcc_do (aubio_mfcc_t * mf, cvec_t * in, fvec_t * out)
   for (j = 0; j < mf->n_filters; j++) {
     for (k = 0; k < mf->n_coefs; k++) {
       out->data[k] += mf->in_dct->data[j]
-          * mf->dct_coeffs->data[j][k];
+          * mf->dct_coeffs->data[k][j];
     }
   }