Speeding up PVQ using unlikely() and moving first position out of the loop
[opus.git] / silk / quant_LTP_gains.c
index 80b2be2..19f555a 100644 (file)
@@ -8,7 +8,7 @@ this list of conditions and the following disclaimer.
 - Redistributions in binary form must reproduce the above copyright
 notice, this list of conditions and the following disclaimer in the
 documentation and/or other materials provided with the distribution.
-- Neither the name of Internet Society, IETF or IETF Trust, nor the 
+- Neither the name of Internet Society, IETF or IETF Trust, nor the
 names of specific contributors, may be used to endorse or promote
 products derived from this software without specific prior written
 permission.
@@ -30,70 +30,86 @@ POSSIBILITY OF SUCH DAMAGE.
 #endif
 
 #include "main.h"
+#include "tuning_parameters.h"
 
 void silk_quant_LTP_gains(
-    opus_int16                  B_Q14[ MAX_NB_SUBFR * LTP_ORDER ],          /* I/O  (un)quantized LTP gains         */
+    opus_int16                  B_Q14[ MAX_NB_SUBFR * LTP_ORDER ],          /* O    Quantized LTP gains             */
     opus_int8                   cbk_index[ MAX_NB_SUBFR ],                  /* O    Codebook Index                  */
     opus_int8                   *periodicity_index,                         /* O    Periodicity Index               */
-    const opus_int32            W_Q18[ MAX_NB_SUBFR*LTP_ORDER*LTP_ORDER ],  /* I    Error Weights in Q18            */
-    opus_int                    mu_Q9,                                      /* I    Mu value (R/D tradeoff)         */
-    opus_int                    lowComplexity,                              /* I    Flag for low complexity         */
-    const opus_int              nb_subfr                                    /* I    number of subframes             */
+    opus_int32                  *sum_log_gain_Q7,                           /* I/O  Cumulative max prediction gain  */
+    opus_int                    *pred_gain_dB_Q7,                           /* O    LTP prediction gain             */
+    const opus_int32            XX_Q17[ MAX_NB_SUBFR*LTP_ORDER*LTP_ORDER ], /* I    Correlation matrix in Q18       */
+    const opus_int32            xX_Q17[ MAX_NB_SUBFR*LTP_ORDER ],           /* I    Correlation vector in Q18       */
+    const opus_int              subfr_len,                                  /* I    Number of samples per subframe  */
+    const opus_int              nb_subfr,                                   /* I    Number of subframes             */
+    int                         arch                                        /* I    Run-time architecture           */
 )
 {
     opus_int             j, k, cbk_size;
     opus_int8            temp_idx[ MAX_NB_SUBFR ];
     const opus_uint8     *cl_ptr_Q5;
     const opus_int8      *cbk_ptr_Q7;
-    const opus_int16     *b_Q14_ptr;
-    const opus_int32     *W_Q18_ptr;
-    opus_int32           rate_dist_Q14_subfr, rate_dist_Q14, min_rate_dist_Q14;
+    const opus_uint8     *cbk_gain_ptr_Q7;
+    const opus_int32     *XX_Q17_ptr, *xX_Q17_ptr;
+    opus_int32           res_nrg_Q15_subfr, res_nrg_Q15, rate_dist_Q7_subfr, rate_dist_Q7, min_rate_dist_Q7;
+    opus_int32           sum_log_gain_tmp_Q7, best_sum_log_gain_Q7, max_gain_Q7, gain_Q7;
 
     /***************************************************/
     /* iterate over different codebooks with different */
     /* rates/distortions, and choose best */
     /***************************************************/
-    min_rate_dist_Q14 = silk_int32_MAX;
+    min_rate_dist_Q7 = silk_int32_MAX;
+    best_sum_log_gain_Q7 = 0;
     for( k = 0; k < 3; k++ ) {
+        /* Safety margin for pitch gain control, to take into account factors
+           such as state rescaling/rewhitening. */
+        opus_int32 gain_safety = SILK_FIX_CONST( 0.4, 7 );
+
         cl_ptr_Q5  = silk_LTP_gain_BITS_Q5_ptrs[ k ];
         cbk_ptr_Q7 = silk_LTP_vq_ptrs_Q7[        k ];
+        cbk_gain_ptr_Q7 = silk_LTP_vq_gain_ptrs_Q7[ k ];
         cbk_size   = silk_LTP_vq_sizes[          k ];
 
-        /* Set up pointer to first subframe */
-        W_Q18_ptr = W_Q18;
-        b_Q14_ptr = B_Q14;
+        /* Set up pointers to first subframe */
+        XX_Q17_ptr = XX_Q17;
+        xX_Q17_ptr = xX_Q17;
 
-        rate_dist_Q14 = 0;
+        res_nrg_Q15 = 0;
+        rate_dist_Q7 = 0;
+        sum_log_gain_tmp_Q7 = *sum_log_gain_Q7;
         for( j = 0; j < nb_subfr; j++ ) {
+            max_gain_Q7 = silk_log2lin( ( SILK_FIX_CONST( MAX_SUM_LOG_GAIN_DB / 6.0, 7 ) - sum_log_gain_tmp_Q7 )
+                                        + SILK_FIX_CONST( 7, 7 ) ) - gain_safety;
             silk_VQ_WMat_EC(
                 &temp_idx[ j ],         /* O    index of best codebook vector                           */
-                &rate_dist_Q14_subfr,   /* O    best weighted quantization error + mu * rate            */
-                b_Q14_ptr,              /* I    input vector to be quantized                            */
-                W_Q18_ptr,              /* I    weighting matrix                                        */
+                &res_nrg_Q15_subfr,     /* O    residual energy                                         */
+                &rate_dist_Q7_subfr,    /* O    best weighted quantization error + mu * rate            */
+                &gain_Q7,               /* O    sum of absolute LTP coefficients                        */
+                XX_Q17_ptr,             /* I    correlation matrix                                      */
+                xX_Q17_ptr,             /* I    correlation vector                                      */
                 cbk_ptr_Q7,             /* I    codebook                                                */
+                cbk_gain_ptr_Q7,        /* I    codebook effective gains                                */
                 cl_ptr_Q5,              /* I    code length for each codebook vector                    */
-                mu_Q9,                  /* I    tradeoff between weighted error and rate                */
-                cbk_size                /* I    number of vectors in codebook                           */
+                subfr_len,              /* I    number of samples per subframe                          */
+                max_gain_Q7,            /* I    maximum sum of absolute LTP coefficients                */
+                cbk_size,               /* I    number of vectors in codebook                           */
+                arch                    /* I    Run-time architecture                                   */
             );
 
-            rate_dist_Q14 = silk_ADD_POS_SAT32( rate_dist_Q14, rate_dist_Q14_subfr );
+            res_nrg_Q15  = silk_ADD_POS_SAT32( res_nrg_Q15, res_nrg_Q15_subfr );
+            rate_dist_Q7 = silk_ADD_POS_SAT32( rate_dist_Q7, rate_dist_Q7_subfr );
+            sum_log_gain_tmp_Q7 = silk_max(0, sum_log_gain_tmp_Q7
+                                + silk_lin2log( gain_safety + gain_Q7 ) - SILK_FIX_CONST( 7, 7 ));
 
-            b_Q14_ptr += LTP_ORDER;
-            W_Q18_ptr += LTP_ORDER * LTP_ORDER;
+            XX_Q17_ptr += LTP_ORDER * LTP_ORDER;
+            xX_Q17_ptr += LTP_ORDER;
         }
 
-        /* Avoid never finding a codebook */
-        rate_dist_Q14 = silk_min( silk_int32_MAX - 1, rate_dist_Q14 );
-
-        if( rate_dist_Q14 < min_rate_dist_Q14 ) {
-            min_rate_dist_Q14 = rate_dist_Q14;
+        if( rate_dist_Q7 <= min_rate_dist_Q7 ) {
+            min_rate_dist_Q7 = rate_dist_Q7;
             *periodicity_index = (opus_int8)k;
             silk_memcpy( cbk_index, temp_idx, nb_subfr * sizeof( opus_int8 ) );
-        }
-
-        /* Break early in low-complexity mode if rate distortion is below threshold */
-        if( lowComplexity && ( rate_dist_Q14 < silk_LTP_gain_middle_avg_RD_Q14 ) ) {
-            break;
+            best_sum_log_gain_Q7 = sum_log_gain_tmp_Q7;
         }
     }
 
@@ -103,5 +119,13 @@ void silk_quant_LTP_gains(
             B_Q14[ j * LTP_ORDER + k ] = silk_LSHIFT( cbk_ptr_Q7[ cbk_index[ j ] * LTP_ORDER + k ], 7 );
         }
     }
-}
 
+    if( nb_subfr == 2 ) {
+        res_nrg_Q15 = silk_RSHIFT32( res_nrg_Q15, 1 );
+    } else {
+        res_nrg_Q15 = silk_RSHIFT32( res_nrg_Q15, 2 );
+    }
+
+    *sum_log_gain_Q7 = best_sum_log_gain_Q7;
+    *pred_gain_dB_Q7 = (opus_int)silk_SMULBB( -3, silk_lin2log( res_nrg_Q15 ) - ( 15 << 7 ) );
+}