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-rw-r--r--media/libopus/silk/control_SNR.c113
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diff --git a/media/libopus/silk/control_SNR.c b/media/libopus/silk/control_SNR.c
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+++ b/media/libopus/silk/control_SNR.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, 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.h"
+#include "tuning_parameters.h"
+
+/* These tables hold SNR values divided by 21 (so they fit in 8 bits)
+ for different target bitrates spaced at 400 bps interval. The first
+ 10 values are omitted (0-4 kb/s) because they're all zeros.
+ These tables were obtained by running different SNRs through the
+ encoder and measuring the active bitrate. */
+static const unsigned char silk_TargetRate_NB_21[117 - 10] = {
+ 0, 15, 39, 52, 61, 68,
+ 74, 79, 84, 88, 92, 95, 99,102,105,108,111,114,117,119,122,124,
+ 126,129,131,133,135,137,139,142,143,145,147,149,151,153,155,157,
+ 158,160,162,163,165,167,168,170,171,173,174,176,177,179,180,182,
+ 183,185,186,187,189,190,192,193,194,196,197,199,200,201,203,204,
+ 205,207,208,209,211,212,213,215,216,217,219,220,221,223,224,225,
+ 227,228,230,231,232,234,235,236,238,239,241,242,243,245,246,248,
+ 249,250,252,253,255
+};
+
+static const unsigned char silk_TargetRate_MB_21[165 - 10] = {
+ 0, 0, 28, 43, 52, 59,
+ 65, 70, 74, 78, 81, 85, 87, 90, 93, 95, 98,100,102,105,107,109,
+ 111,113,115,116,118,120,122,123,125,127,128,130,131,133,134,136,
+ 137,138,140,141,143,144,145,147,148,149,151,152,153,154,156,157,
+ 158,159,160,162,163,164,165,166,167,168,169,171,172,173,174,175,
+ 176,177,178,179,180,181,182,183,184,185,186,187,188,188,189,190,
+ 191,192,193,194,195,196,197,198,199,200,201,202,203,203,204,205,
+ 206,207,208,209,210,211,212,213,214,214,215,216,217,218,219,220,
+ 221,222,223,224,224,225,226,227,228,229,230,231,232,233,234,235,
+ 236,236,237,238,239,240,241,242,243,244,245,246,247,248,249,250,
+ 251,252,253,254,255
+};
+
+static const unsigned char silk_TargetRate_WB_21[201 - 10] = {
+ 0, 0, 0, 8, 29, 41,
+ 49, 56, 62, 66, 70, 74, 77, 80, 83, 86, 88, 91, 93, 95, 97, 99,
+ 101,103,105,107,108,110,112,113,115,116,118,119,121,122,123,125,
+ 126,127,129,130,131,132,134,135,136,137,138,140,141,142,143,144,
+ 145,146,147,148,149,150,151,152,153,154,156,157,158,159,159,160,
+ 161,162,163,164,165,166,167,168,169,170,171,171,172,173,174,175,
+ 176,177,177,178,179,180,181,181,182,183,184,185,185,186,187,188,
+ 189,189,190,191,192,192,193,194,195,195,196,197,198,198,199,200,
+ 200,201,202,203,203,204,205,206,206,207,208,209,209,210,211,211,
+ 212,213,214,214,215,216,216,217,218,219,219,220,221,221,222,223,
+ 224,224,225,226,226,227,228,229,229,230,231,232,232,233,234,234,
+ 235,236,237,237,238,239,240,240,241,242,243,243,244,245,246,246,
+ 247,248,249,249,250,251,252,253,255
+};
+
+/* Control SNR of redidual quantizer */
+opus_int silk_control_SNR(
+ silk_encoder_state *psEncC, /* I/O Pointer to Silk encoder state */
+ opus_int32 TargetRate_bps /* I Target max bitrate (bps) */
+)
+{
+ int id;
+ int bound;
+ const unsigned char *snr_table;
+
+ psEncC->TargetRate_bps = TargetRate_bps;
+ if( psEncC->nb_subfr == 2 ) {
+ TargetRate_bps -= 2000 + psEncC->fs_kHz/16;
+ }
+ if( psEncC->fs_kHz == 8 ) {
+ bound = sizeof(silk_TargetRate_NB_21);
+ snr_table = silk_TargetRate_NB_21;
+ } else if( psEncC->fs_kHz == 12 ) {
+ bound = sizeof(silk_TargetRate_MB_21);
+ snr_table = silk_TargetRate_MB_21;
+ } else {
+ bound = sizeof(silk_TargetRate_WB_21);
+ snr_table = silk_TargetRate_WB_21;
+ }
+ id = (TargetRate_bps+200)/400;
+ id = silk_min(id - 10, bound-1);
+ if( id <= 0 ) {
+ psEncC->SNR_dB_Q7 = 0;
+ } else {
+ psEncC->SNR_dB_Q7 = snr_table[id]*21;
+ }
+ return SILK_NO_ERROR;
+}