Part 2 of 2 of Kenan Gillet's 'make ff_qcelp_lspf2lpc

more general' changeset. This one relocates the QCELP
especific code to the qcelpdec.* files.

Originally committed as revision 17800 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/qcelp_lsp.c

@@ -29,15 +29,6 @@
 
 #include "libavutil/mathematics.h"
 
-/**
- * initial coefficient to perform bandwidth expansion on LPC
- *
- * @note: 0.9883 looks like an approximation of 253/256.
- *
- * TIA/EIA/IS-733 2.4.3.3.6 6
- */
-#define QCELP_BANDWITH_EXPANSION_COEFF 0.9883
-
 /**
  * Computes the Pa / (1 + z(-1)) or Qa / (1 - z(-1)) coefficients
  * needed for LSP to LPC conversion.
@@ -84,37 +75,7 @@ void ff_celp_lspf2lpc(const double *lspf, float *lpc)
         double paf = pa[i+1] + pa[i];
         double qaf = qa[i+1] - qa[i];
 
-        lpc[i  ] = 0.5 * (paf+qaf);
-        lpc[9-i] = 0.5 * (paf-qaf);
-    }
-}
-
-/**
- * Reconstructs LPC coefficients from the line spectral pair frequencies
- * and performs bandwidth expansion.
- *
- * @param lspf line spectral pair frequencies
- * @param lpc linear predictive coding coefficients
- *
- * @note: bandwith_expansion_coeff could be precalculated into a table
- *        but it seems to be slower on x86
- *
- * TIA/EIA/IS-733 2.4.3.3.5
- */
-void ff_qcelp_lspf2lpc(const float *lspf, float *lpc)
-{
-    double lsf[10];
-    double bandwith_expansion_coeff = QCELP_BANDWITH_EXPANSION_COEFF;
-    int   i;
-
-    for (i=0; i<10; i++)
-        lsf[i] = cos(M_PI * lspf[i]);
-
-    ff_celp_lspf2lpc(lsf, lpc);
-
-    for (i=0; i<10; i++)
-    {
-        lpc[i] *= bandwith_expansion_coeff;
-        bandwith_expansion_coeff *= QCELP_BANDWITH_EXPANSION_COEFF;
+        lpc[i  ] = 0.5*(paf+qaf);
+        lpc[9-i] = 0.5*(paf-qaf);
     }
 }

libavcodec/qcelpdata.h

@@ -550,4 +550,13 @@ static const double qcelp_rnd_fir_coefs[11] = {
  */
 #define QCELP_LSP_OCTAVE_PREDICTOR 29.0/32
 
+/**
+ * initial coefficient to perform bandwidth expansion on LPC
+ *
+ * @note: 0.9883 looks like an approximation of 253/256.
+ *
+ * TIA/EIA/IS-733 2.4.3.3.6 6
+ */
+#define QCELP_BANDWITH_EXPANSION_COEFF 0.9883
+
 #endif /* AVCODEC_QCELPDATA_H */

libavcodec/qcelpdec.c

@@ -79,7 +79,7 @@ typedef struct
  *
  * TIA/EIA/IS-733 2.4.3.3.5
  */
-void ff_qcelp_lspf2lpc(const float *lspf, float *lpc);
+void ff_celp_lspf2lpc(const double *lspf, float *lpc);
 
 static void weighted_vector_sumf(float *out, const float *in_a,
                                  const float *in_b, float weight_coeff_a,
@@ -584,6 +584,36 @@ static void apply_pitch_filters(QCELPContext *q, float *cdn_vector)
     }
 }
 
+/**
+ * Reconstructs LPC coefficients from the line spectral pair frequencies
+ * and performs bandwidth expansion.
+ *
+ * @param lspf line spectral pair frequencies
+ * @param lpc linear predictive coding coefficients
+ *
+ * @note: bandwith_expansion_coeff could be precalculated into a table
+ *        but it seems to be slower on x86
+ *
+ * TIA/EIA/IS-733 2.4.3.3.5
+ */
+void lspf2lpc(const float *lspf, float *lpc)
+{
+    double lsf[10];
+    double bandwith_expansion_coeff = QCELP_BANDWITH_EXPANSION_COEFF;
+    int   i;
+
+    for (i=0; i<10; i++)
+        lsf[i] = cos(M_PI * lspf[i]);
+
+    ff_celp_lspf2lpc(lsf, lpc);
+
+    for (i=0; i<10; i++)
+    {
+        lpc[i] *= bandwith_expansion_coeff;
+        bandwith_expansion_coeff *= QCELP_BANDWITH_EXPANSION_COEFF;
+    }
+}
+
 /**
  * Interpolates LSP frequencies and computes LPC coefficients
  * for a given bitrate & pitch subframe.
@@ -612,12 +642,12 @@ void interpolate_lpc(QCELPContext *q, const float *curr_lspf, float *lpc,
     {
         weighted_vector_sumf(interpolated_lspf, curr_lspf, q->prev_lspf,
                              weight, 1.0 - weight, 10);
-        ff_qcelp_lspf2lpc(interpolated_lspf, lpc);
+        lspf2lpc(interpolated_lspf, lpc);
     }else if(q->bitrate >= RATE_QUARTER ||
              (q->bitrate == I_F_Q && !subframe_num))
-        ff_qcelp_lspf2lpc(curr_lspf, lpc);
+        lspf2lpc(curr_lspf, lpc);
     else if(q->bitrate == SILENCE && !subframe_num)
-        ff_qcelp_lspf2lpc(q->prev_lspf, lpc);
+        lspf2lpc(q->prev_lspf, lpc);
 }
 
 static qcelp_packet_rate buf_size2bitrate(const int buf_size)