1 files changed, 47 insertions, 0 deletions
diff --git a/src_SigProc_FLP/SKP_Silk_bwexpander_FLP.c b/src_SigProc_FLP/SKP_Silk_bwexpander_FLP.c
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+++ b/src_SigProc_FLP/SKP_Silk_bwexpander_FLP.c
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+/***********************************************************************
+Copyright (c) 2006-2011, Skype Limited. All rights reserved. 
+Redistribution and use in source and binary forms, with or without 
+modification, (subject to the limitations in the disclaimer below) 
+are permitted provided that the following conditions are met:
+- Redistributions of source code must retain the above copyright notice,
+this list of conditions and the following disclaimer.
+- Redistributions in binary form must reproduce the above copyright 
+notice, this list of conditions and the following disclaimer in the 
+documentation and/or other materials provided with the distribution.
+- Neither the name of Skype Limited, nor the names of specific 
+contributors, may be used to endorse or promote products derived from 
+this software without specific prior written permission.
+NO EXPRESS OR IMPLIED LICENSES TO ANY PARTY'S PATENT RIGHTS ARE GRANTED 
+BY THIS LICENSE. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 
+CONTRIBUTORS ''AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
+BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 
+FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 
+COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 
+INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 
+USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON 
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+***********************************************************************/
+
+
+#include "SKP_Silk_SigProc_FLP.h"
+
+
+/* Chirp (bw expand) LP AR filter */
+void SKP_Silk_bwexpander_FLP( 
+    SKP_float           *ar,        /* I/O  AR filter to be expanded (without leading 1)    */
+    const SKP_int       d,          /* I    length of ar                                    */
+    const SKP_float     chirp       /* I    chirp factor (typically in range (0..1) )       */
+)
+{
+    SKP_int   i;
+    SKP_float cfac = chirp;
+
+    for( i = 0; i < d - 1; i++ ) {
+        ar[ i ] *=  cfac;
+        cfac    *=  chirp;
+    }
+    ar[ d - 1 ] *=  cfac;
+}