ref: 7cf79a7a5cbe4cdb2ac61d8474cc52b89545f2e0
parent: 0de9d8abec2fe2a2477c88b0974ca5f4abcb64ff
author: Jean-Marc Valin <[email protected]>
date: Mon Mar 24 17:39:49 EDT 2008
Unrolled the inner loop in vq_index() so that the codebook unpacking doesn't require a branch.
--- a/libcelt/quant_pitch.c
+++ b/libcelt/quant_pitch.c
@@ -1,4 +1,4 @@
-/* (C) 2007 Jean-Marc Valin, CSIRO
+/* (C) 2007-2008 Jean-Marc Valin, CSIRO
*/
/*
Redistribution and use in source and binary forms, with or without
@@ -40,16 +40,20 @@
#include "mathops.h"
#ifdef FIXED_POINT
-#define PGAIN(codebook, i) ((i)&1 ? (celt_word16_t)(((codebook)[(i)>>1]&0x00ffU)<<7) : (celt_word16_t)(((codebook)[(i)>>1]&0xff00U)>>1) )
+#define PGAIN_ODD(codebook, i) ((celt_word16_t)(((codebook)[(i)]&0x00ffU)<<7))
+#define PGAIN_EVEN(codebook, i) ((celt_word16_t)(((codebook)[(i)]&0xff00U)>>1))
+
#else
-#define PGAIN(codebook, i) ((1.f/32768.f)*((i)&1 ? (celt_word16_t)(((codebook)[(i)>>1]&0x00ffU)<<7) : (celt_word16_t)(((codebook)[(i)>>1]&0xff00U)>>1) ))
+#define PGAIN_ODD(codebook, i) ((1.f/32768.f)*(celt_word16_t)(((codebook)[(i)]&0x00ffU)<<7))
+#define PGAIN_EVEN(codebook, i) ((1.f/32768.f)*(celt_word16_t)(((codebook)[(i)]&0xff00U)>>1) )
#endif
+#define PGAIN(codebook, i) ((i)&1 ? PGAIN_ODD(codebook, (i)>>1) : PGAIN_EVEN(codebook, (i)>>1))
+
#define Q1515ONE MULT16_16(Q15ONE,Q15ONE)
-/* Taken from Speex.
- Finds the index of the entry in a codebook that best matches the input*/
+/** Taken from Speex.Finds the index of the entry in a codebook that best matches the input*/
int vq_index(celt_pgain_t *in, const celt_uint16_t *codebook, int len, int entries)
{int i,j;
@@ -59,11 +63,13 @@
for (i=0;i<entries;i++)
{celt_word32_t dist=0;
- for (j=0;j<len;j++)
+ for (j=0;j<len>>1;j++)
{- celt_pgain_t tmp = SHR16(SUB16(in[j],PGAIN(codebook, ind)),1);
+ celt_pgain_t tmp1 = SHR16(SUB16(in[2*j],PGAIN_EVEN(codebook, ind)),1);
+ celt_pgain_t tmp2 = SHR16(SUB16(in[2*j+1],PGAIN_ODD(codebook, ind)),1);
ind++;
- dist = MAC16_16(dist, tmp, tmp);
+ dist = MAC16_16(dist, tmp1, tmp1);
+ dist = MAC16_16(dist, tmp2, tmp2);
}
if (i==0 || dist<min_dist)
{@@ -74,6 +80,7 @@
return best_index;
}
+/** Returns the pitch gain vector corresponding to a certain id */
static void id2gains(int id, celt_pgain_t *gains, int len)
{int i;