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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /media/libopus/silk/LPC_fit.c
parentInitial commit. (diff)
downloadfirefox-esr-upstream.tar.xz
firefox-esr-upstream.zip
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'media/libopus/silk/LPC_fit.c')
-rw-r--r--media/libopus/silk/LPC_fit.c82
1 files changed, 82 insertions, 0 deletions
diff --git a/media/libopus/silk/LPC_fit.c b/media/libopus/silk/LPC_fit.c
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+++ b/media/libopus/silk/LPC_fit.c
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+/***********************************************************************
+Copyright (c) 2013, Koen Vos. 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 "SigProc_FIX.h"
+
+/* Convert int32 coefficients to int16 coefs and make sure there's no wrap-around.
+ This logic is reused in _celt_lpc(). Any bug fixes should also be applied there. */
+void silk_LPC_fit(
+ opus_int16 *a_QOUT, /* O Output signal */
+ opus_int32 *a_QIN, /* I/O Input signal */
+ const opus_int QOUT, /* I Input Q domain */
+ const opus_int QIN, /* I Input Q domain */
+ const opus_int d /* I Filter order */
+)
+{
+ opus_int i, k, idx = 0;
+ opus_int32 maxabs, absval, chirp_Q16;
+
+ /* Limit the maximum absolute value of the prediction coefficients, so that they'll fit in int16 */
+ for( i = 0; i < 10; i++ ) {
+ /* Find maximum absolute value and its index */
+ maxabs = 0;
+ for( k = 0; k < d; k++ ) {
+ absval = silk_abs( a_QIN[k] );
+ if( absval > maxabs ) {
+ maxabs = absval;
+ idx = k;
+ }
+ }
+ maxabs = silk_RSHIFT_ROUND( maxabs, QIN - QOUT );
+
+ if( maxabs > silk_int16_MAX ) {
+ /* Reduce magnitude of prediction coefficients */
+ maxabs = silk_min( maxabs, 163838 ); /* ( silk_int32_MAX >> 14 ) + silk_int16_MAX = 163838 */
+ chirp_Q16 = SILK_FIX_CONST( 0.999, 16 ) - silk_DIV32( silk_LSHIFT( maxabs - silk_int16_MAX, 14 ),
+ silk_RSHIFT32( silk_MUL( maxabs, idx + 1), 2 ) );
+ silk_bwexpander_32( a_QIN, d, chirp_Q16 );
+ } else {
+ break;
+ }
+ }
+
+ if( i == 10 ) {
+ /* Reached the last iteration, clip the coefficients */
+ for( k = 0; k < d; k++ ) {
+ a_QOUT[ k ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( a_QIN[ k ], QIN - QOUT ) );
+ a_QIN[ k ] = silk_LSHIFT( (opus_int32)a_QOUT[ k ], QIN - QOUT );
+ }
+ } else {
+ for( k = 0; k < d; k++ ) {
+ a_QOUT[ k ] = (opus_int16)silk_RSHIFT_ROUND( a_QIN[ k ], QIN - QOUT );
+ }
+ }
+}