git-svn-id: http://webrtc.googlecode.com/svn/trunk@4 4adac7df-926f-26a2-2b94-8c16560cd09d

2011-05-30 11:22:19 +00:00
parent 01813fe945
commit 77ae29bc81
1153 changed files with 404089 additions and 0 deletions
--- a/modules/audio_coding/codecs/iLBC/main/source/state_search.c
+++ b/modules/audio_coding/codecs/iLBC/main/source/state_search.c
@@ -0,0 +1,119 @@
+/*
+ *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+/******************************************************************
+
+ iLBC Speech Coder ANSI-C Source Code
+
+ WebRtcIlbcfix_StateSearch.c
+
+******************************************************************/
+
+#include "defines.h"
+#include "constants.h"
+#include "abs_quant.h"
+
+/*----------------------------------------------------------------*
+ *  encoding of start state
+ *---------------------------------------------------------------*/
+
+void WebRtcIlbcfix_StateSearch(
+    iLBC_Enc_Inst_t *iLBCenc_inst,
+    /* (i) Encoder instance */
+    iLBC_bits *iLBC_encbits,/* (i/o) Encoded bits (output idxForMax
+                               and idxVec, input state_first) */
+    WebRtc_Word16 *residual,   /* (i) target residual vector */
+    WebRtc_Word16 *syntDenum,  /* (i) lpc synthesis filter */
+    WebRtc_Word16 *weightDenum  /* (i) weighting filter denuminator */
+                               ) {
+  WebRtc_Word16 k, index;
+  WebRtc_Word16 maxVal;
+  WebRtc_Word16 scale, shift;
+  WebRtc_Word32 maxValsq;
+  WebRtc_Word16 scaleRes;
+  WebRtc_Word16 max;
+  int i;
+  /* Stack based */
+  WebRtc_Word16 numerator[1+LPC_FILTERORDER];
+  WebRtc_Word16 residualLongVec[2*STATE_SHORT_LEN_30MS+LPC_FILTERORDER];
+  WebRtc_Word16 sampleMa[2*STATE_SHORT_LEN_30MS];
+  WebRtc_Word16 *residualLong = &residualLongVec[LPC_FILTERORDER];
+  WebRtc_Word16 *sampleAr = residualLong;
+
+  /* Scale to maximum 12 bits to avoid saturation in circular convolution filter */
+  max = WebRtcSpl_MaxAbsValueW16(residual, iLBCenc_inst->state_short_len);
+  scaleRes = WebRtcSpl_GetSizeInBits(max)-12;
+  scaleRes = WEBRTC_SPL_MAX(0, scaleRes);
+  /* Set up the filter coefficients for the circular convolution */
+  for (i=0; i<LPC_FILTERORDER+1; i++) {
+    numerator[i] = (syntDenum[LPC_FILTERORDER-i]>>scaleRes);
+  }
+
+  /* Copy the residual to a temporary buffer that we can filter
+   * and set the remaining samples to zero.
+   */
+  WEBRTC_SPL_MEMCPY_W16(residualLong, residual, iLBCenc_inst->state_short_len);
+  WebRtcSpl_MemSetW16(residualLong + iLBCenc_inst->state_short_len, 0, iLBCenc_inst->state_short_len);
+
+  /* Run the Zero-Pole filter (Ciurcular convolution) */
+  WebRtcSpl_MemSetW16(residualLongVec, 0, LPC_FILTERORDER);
+  WebRtcSpl_FilterMAFastQ12(
+      residualLong, sampleMa,
+      numerator, LPC_FILTERORDER+1, (WebRtc_Word16)(iLBCenc_inst->state_short_len + LPC_FILTERORDER));
+  WebRtcSpl_MemSetW16(&sampleMa[iLBCenc_inst->state_short_len + LPC_FILTERORDER], 0, iLBCenc_inst->state_short_len - LPC_FILTERORDER);
+
+  WebRtcSpl_FilterARFastQ12(
+      sampleMa, sampleAr,
+      syntDenum, LPC_FILTERORDER+1, (WebRtc_Word16)(2*iLBCenc_inst->state_short_len));
+
+  for(k=0;k<iLBCenc_inst->state_short_len;k++){
+    sampleAr[k] += sampleAr[k+iLBCenc_inst->state_short_len];
+  }
+
+  /* Find maximum absolute value in the vector */
+  maxVal=WebRtcSpl_MaxAbsValueW16(sampleAr, iLBCenc_inst->state_short_len);
+
+  /* Find the best index */
+
+  if ((((WebRtc_Word32)maxVal)<<scaleRes)<23170) {
+    maxValsq=((WebRtc_Word32)maxVal*maxVal)<<(2+2*scaleRes);
+  } else {
+    maxValsq=(WebRtc_Word32)WEBRTC_SPL_WORD32_MAX;
+  }
+
+  index=0;
+  for (i=0;i<63;i++) {
+
+    if (maxValsq>=WebRtcIlbcfix_kChooseFrgQuant[i]) {
+      index=i+1;
+    } else {
+      i=63;
+    }
+  }
+  iLBC_encbits->idxForMax=index;
+
+  /* Rescale the vector before quantization */
+  scale=WebRtcIlbcfix_kScale[index];
+
+  if (index<27) { /* scale table is in Q16, fout[] is in Q(-1) and we want the result to be in Q11 */
+    shift=4;
+  } else { /* scale table is in Q21, fout[] is in Q(-1) and we want the result to be in Q11 */
+    shift=9;
+  }
+
+  /* Set up vectors for AbsQuant and rescale it with the scale factor */
+  WebRtcSpl_ScaleVectorWithSat(sampleAr, sampleAr, scale,
+                              iLBCenc_inst->state_short_len, (WebRtc_Word16)(shift-scaleRes));
+
+  /* Quantize the values in fout[] */
+  WebRtcIlbcfix_AbsQuant(iLBCenc_inst, iLBC_encbits, sampleAr, weightDenum);
+
+  return;
+}