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-rw-r--r--third_party/libwebrtc/modules/audio_coding/codecs/ilbc/bw_expand.c44
1 files changed, 44 insertions, 0 deletions
diff --git a/third_party/libwebrtc/modules/audio_coding/codecs/ilbc/bw_expand.c b/third_party/libwebrtc/modules/audio_coding/codecs/ilbc/bw_expand.c
new file mode 100644
index 0000000000..1a9b882adf
--- /dev/null
+++ b/third_party/libwebrtc/modules/audio_coding/codecs/ilbc/bw_expand.c
@@ -0,0 +1,44 @@
+/*
+ * 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_BwExpand.c
+
+******************************************************************/
+
+#include "modules/audio_coding/codecs/ilbc/bw_expand.h"
+
+#include "modules/audio_coding/codecs/ilbc/defines.h"
+
+/*----------------------------------------------------------------*
+ * lpc bandwidth expansion
+ *---------------------------------------------------------------*/
+
+/* The output is in the same domain as the input */
+void WebRtcIlbcfix_BwExpand(
+ int16_t *out, /* (o) the bandwidth expanded lpc coefficients */
+ int16_t *in, /* (i) the lpc coefficients before bandwidth
+ expansion */
+ int16_t *coef, /* (i) the bandwidth expansion factor Q15 */
+ int16_t length /* (i) the length of lpc coefficient vectors */
+ ) {
+ int i;
+
+ out[0] = in[0];
+ for (i = 1; i < length; i++) {
+ /* out[i] = coef[i] * in[i] with rounding.
+ in[] and out[] are in Q12 and coef[] is in Q15
+ */
+ out[i] = (int16_t)((coef[i] * in[i] + 16384) >> 15);
+ }
+}