blob: bc209521324f524b91459a235ec2f08a62c7b037 [file] [log] [blame]
 /* * 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_Vq4.c ******************************************************************/ #include "vq4.h" #include "constants.h" /*----------------------------------------------------------------* * vector quantization *---------------------------------------------------------------*/ void WebRtcIlbcfix_Vq4( int16_t *Xq, /* quantized vector (Q13) */ int16_t *index, int16_t *CB, /* codebook in Q13 */ int16_t *X, /* vector to quantize (Q13) */ int16_t n_cb ){ int16_t i, j; int16_t pos, minindex=0; int16_t tmp; int32_t dist, mindist; pos = 0; mindist = WEBRTC_SPL_WORD32_MAX; /* start value */ /* Find the codebook with the lowest square distance */ for (j = 0; j < n_cb; j++) { tmp = X[0] - CB[pos]; dist = tmp * tmp; for (i = 1; i < 4; i++) { tmp = X[i] - CB[pos + i]; dist += tmp * tmp; } if (dist < mindist) { mindist = dist; minindex = j; } pos += 4; } /* Store the quantized codebook and the index */ for (i = 0; i < 4; i++) { Xq[i] = CB[minindex*4 + i]; } *index = minindex; }