1 files changed, 113 insertions, 0 deletions

diff --git a/lib/rbcodec/codecs/libopus/silk/control_SNR.c b/lib/rbcodec/codecs/libopus/silk/control_SNR.c
new file mode 100644
index 0000000000..9a6db27543
--- /dev/null
+++ b/lib/rbcodec/codecs/libopus/silk/control_SNR.c
@@ -0,0 +1,113 @@
+/***********************************************************************
+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;
+}