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

modules/audio_coding/NetEQ/main/source/mute_signal.c

@@ -0,0 +1,33 @@
+/*
+ *  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.
+ */
+
+/*
+ * This function mutes a signal linearly on a sample by sample basis.
+ */
+
+#include "dsp_helpfunctions.h"
+
+#include "signal_processing_library.h"
+
+void WebRtcNetEQ_MuteSignal(WebRtc_Word16 *pw16_inout, WebRtc_Word16 muteSlope,
+                            WebRtc_Word16 N)
+{
+    int i;
+    WebRtc_Word32 w32_tmp = 1048608; /* (16384<<6 + 32) */
+
+    for (i = 0; i < N; i++)
+    {
+        pw16_inout[i]
+            = (WebRtc_Word16) ((WEBRTC_SPL_MUL_16_16((WebRtc_Word16)(w32_tmp>>6), pw16_inout[i])
+                + 8192) >> 14);
+        w32_tmp -= muteSlope;
+    }
+}
+