Create local copy of Opus v1.1.2

webrtc/modules/audio_coding/codecs/opus/opus/src/silk/float/LTP_analysis_filter_FLP.c

Index: webrtc/modules/audio_coding/codecs/opus/opus/src/silk/float/LTP_analysis_filter_FLP.c
diff --git a/webrtc/modules/audio_coding/codecs/opus/opus/src/silk/float/LTP_analysis_filter_FLP.c b/webrtc/modules/audio_coding/codecs/opus/opus/src/silk/float/LTP_analysis_filter_FLP.c
new file mode 100644
index 0000000000000000000000000000000000000000..849b7c1c528ba6dc4bf2607edba419d760524097
--- /dev/null
+++ b/webrtc/modules/audio_coding/codecs/opus/opus/src/silk/float/LTP_analysis_filter_FLP.c
@@ -0,0 +1,75 @@
+/***********************************************************************
+Copyright (c) 2006-2011, Skype Limited. All rights reserved.
+Redistribution and use in source and binary forms, with or without
+modification, 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 Internet Society, IETF or IETF Trust, nor the
+names of specific contributors, may be used to endorse or promote
+products derived from this software without specific prior written
+permission.
+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.
+***********************************************************************/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "main_FLP.h"
+
+void silk_LTP_analysis_filter_FLP(
+    silk_float                      *LTP_res,                           /* O    LTP res MAX_NB_SUBFR*(pre_lgth+subfr_lngth) */
+    const silk_float                *x,                                 /* I    Input signal, with preceding samples        */
+    const silk_float                B[ LTP_ORDER * MAX_NB_SUBFR ],      /* I    LTP coefficients for each subframe          */
+    const opus_int                  pitchL[   MAX_NB_SUBFR ],           /* I    Pitch lags                                  */
+    const silk_float                invGains[ MAX_NB_SUBFR ],           /* I    Inverse quantization gains                  */
+    const opus_int                  subfr_length,                       /* I    Length of each subframe                     */
+    const opus_int                  nb_subfr,                           /* I    number of subframes                         */
+    const opus_int                  pre_length                          /* I    Preceding samples for each subframe         */
+)
+{
+    const silk_float *x_ptr, *x_lag_ptr;
+    silk_float   Btmp[ LTP_ORDER ];
+    silk_float   *LTP_res_ptr;
+    silk_float   inv_gain;
+    opus_int     k, i, j;
+
+    x_ptr = x;
+    LTP_res_ptr = LTP_res;
+    for( k = 0; k < nb_subfr; k++ ) {
+        x_lag_ptr = x_ptr - pitchL[ k ];
+        inv_gain = invGains[ k ];
+        for( i = 0; i < LTP_ORDER; i++ ) {
+            Btmp[ i ] = B[ k * LTP_ORDER + i ];
+        }
+
+        /* LTP analysis FIR filter */
+        for( i = 0; i < subfr_length + pre_length; i++ ) {
+            LTP_res_ptr[ i ] = x_ptr[ i ];
+            /* Subtract long-term prediction */
+            for( j = 0; j < LTP_ORDER; j++ ) {
+                LTP_res_ptr[ i ] -= Btmp[ j ] * x_lag_ptr[ LTP_ORDER / 2 - j ];
+            }
+            LTP_res_ptr[ i ] *= inv_gain;
+            x_lag_ptr++;
+        }
+
+        /* Update pointers */
+        LTP_res_ptr += subfr_length + pre_length;
+        x_ptr       += subfr_length;
+    }
+}