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-rw-r--r--third_party/libwebrtc/modules/audio_coding/codecs/ilbc/decoder_interpolate_lsf.c85
1 files changed, 85 insertions, 0 deletions
diff --git a/third_party/libwebrtc/modules/audio_coding/codecs/ilbc/decoder_interpolate_lsf.c b/third_party/libwebrtc/modules/audio_coding/codecs/ilbc/decoder_interpolate_lsf.c
new file mode 100644
index 0000000000..d96bb9b2e9
--- /dev/null
+++ b/third_party/libwebrtc/modules/audio_coding/codecs/ilbc/decoder_interpolate_lsf.c
@@ -0,0 +1,85 @@
+/*
+ * 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_DecoderInterpolateLsp.c
+
+******************************************************************/
+
+#include "modules/audio_coding/codecs/ilbc/decoder_interpolate_lsf.h"
+
+#include "modules/audio_coding/codecs/ilbc/bw_expand.h"
+#include "modules/audio_coding/codecs/ilbc/constants.h"
+#include "modules/audio_coding/codecs/ilbc/defines.h"
+#include "modules/audio_coding/codecs/ilbc/lsf_interpolate_to_poly_dec.h"
+
+/*----------------------------------------------------------------*
+ * obtain synthesis and weighting filters form lsf coefficients
+ *---------------------------------------------------------------*/
+
+void WebRtcIlbcfix_DecoderInterpolateLsp(
+ int16_t *syntdenum, /* (o) synthesis filter coefficients */
+ int16_t *weightdenum, /* (o) weighting denumerator
+ coefficients */
+ int16_t *lsfdeq, /* (i) dequantized lsf coefficients */
+ int16_t length, /* (i) length of lsf coefficient vector */
+ IlbcDecoder *iLBCdec_inst
+ /* (i) the decoder state structure */
+ ){
+ size_t i;
+ int pos, lp_length;
+ int16_t lp[LPC_FILTERORDER + 1], *lsfdeq2;
+
+ lsfdeq2 = lsfdeq + length;
+ lp_length = length + 1;
+
+ if (iLBCdec_inst->mode==30) {
+ /* subframe 1: Interpolation between old and first LSF */
+
+ WebRtcIlbcfix_LspInterpolate2PolyDec(lp, (*iLBCdec_inst).lsfdeqold, lsfdeq,
+ WebRtcIlbcfix_kLsfWeight30ms[0], length);
+ WEBRTC_SPL_MEMCPY_W16(syntdenum,lp,lp_length);
+ WebRtcIlbcfix_BwExpand(weightdenum, lp, (int16_t*)WebRtcIlbcfix_kLpcChirpSyntDenum, (int16_t)lp_length);
+
+ /* subframes 2 to 6: interpolation between first and last LSF */
+
+ pos = lp_length;
+ for (i = 1; i < 6; i++) {
+ WebRtcIlbcfix_LspInterpolate2PolyDec(lp, lsfdeq, lsfdeq2,
+ WebRtcIlbcfix_kLsfWeight30ms[i], length);
+ WEBRTC_SPL_MEMCPY_W16(syntdenum + pos,lp,lp_length);
+ WebRtcIlbcfix_BwExpand(weightdenum + pos, lp,
+ (int16_t*)WebRtcIlbcfix_kLpcChirpSyntDenum, (int16_t)lp_length);
+ pos += lp_length;
+ }
+ } else { /* iLBCdec_inst->mode=20 */
+ /* subframes 1 to 4: interpolation between old and new LSF */
+ pos = 0;
+ for (i = 0; i < iLBCdec_inst->nsub; i++) {
+ WebRtcIlbcfix_LspInterpolate2PolyDec(lp, iLBCdec_inst->lsfdeqold, lsfdeq,
+ WebRtcIlbcfix_kLsfWeight20ms[i], length);
+ WEBRTC_SPL_MEMCPY_W16(syntdenum+pos,lp,lp_length);
+ WebRtcIlbcfix_BwExpand(weightdenum+pos, lp,
+ (int16_t*)WebRtcIlbcfix_kLpcChirpSyntDenum, (int16_t)lp_length);
+ pos += lp_length;
+ }
+ }
+
+ /* update memory */
+
+ if (iLBCdec_inst->mode==30) {
+ WEBRTC_SPL_MEMCPY_W16(iLBCdec_inst->lsfdeqold, lsfdeq2, length);
+ } else {
+ WEBRTC_SPL_MEMCPY_W16(iLBCdec_inst->lsfdeqold, lsfdeq, length);
+ }
+}