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comparison: media/libopus/silk/control_SNR.c
media/libopus/silk/control_SNR.c
- branch
- TOR_BUG_9701
- changeset 15
- b8a032363ba2
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| -1:000000000000 | 0:f80c9004f542 |
|---|---|
| 1 /*********************************************************************** | |
| 2 Copyright (c) 2006-2011, Skype Limited. All rights reserved. | |
| 3 Redistribution and use in source and binary forms, with or without | |
| 4 modification, are permitted provided that the following conditions | |
| 5 are met: | |
| 6 - Redistributions of source code must retain the above copyright notice, | |
| 7 this list of conditions and the following disclaimer. | |
| 8 - Redistributions in binary form must reproduce the above copyright | |
| 9 notice, this list of conditions and the following disclaimer in the | |
| 10 documentation and/or other materials provided with the distribution. | |
| 11 - Neither the name of Internet Society, IETF or IETF Trust, nor the | |
| 12 names of specific contributors, may be used to endorse or promote | |
| 13 products derived from this software without specific prior written | |
| 14 permission. | |
| 15 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" | |
| 16 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
| 17 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
| 18 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE | |
| 19 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR | |
| 20 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF | |
| 21 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS | |
| 22 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN | |
| 23 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) | |
| 24 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE | |
| 25 POSSIBILITY OF SUCH DAMAGE. | |
| 26 ***********************************************************************/ | |
| 27 | |
| 28 #ifdef HAVE_CONFIG_H | |
| 29 #include "config.h" | |
| 30 #endif | |
| 31 | |
| 32 #include "main.h" | |
| 33 #include "tuning_parameters.h" | |
| 34 | |
| 35 /* Control SNR of redidual quantizer */ | |
| 36 opus_int silk_control_SNR( | |
| 37 silk_encoder_state *psEncC, /* I/O Pointer to Silk encoder state */ | |
| 38 opus_int32 TargetRate_bps /* I Target max bitrate (bps) */ | |
| 39 ) | |
| 40 { | |
| 41 opus_int k, ret = SILK_NO_ERROR; | |
| 42 opus_int32 frac_Q6; | |
| 43 const opus_int32 *rateTable; | |
| 44 | |
| 45 /* Set bitrate/coding quality */ | |
| 46 TargetRate_bps = silk_LIMIT( TargetRate_bps, MIN_TARGET_RATE_BPS, MAX_TARGET_RATE_BPS ); | |
| 47 if( TargetRate_bps != psEncC->TargetRate_bps ) { | |
| 48 psEncC->TargetRate_bps = TargetRate_bps; | |
| 49 | |
| 50 /* If new TargetRate_bps, translate to SNR_dB value */ | |
| 51 if( psEncC->fs_kHz == 8 ) { | |
| 52 rateTable = silk_TargetRate_table_NB; | |
| 53 } else if( psEncC->fs_kHz == 12 ) { | |
| 54 rateTable = silk_TargetRate_table_MB; | |
| 55 } else { | |
| 56 rateTable = silk_TargetRate_table_WB; | |
| 57 } | |
| 58 | |
| 59 /* Reduce bitrate for 10 ms modes in these calculations */ | |
| 60 if( psEncC->nb_subfr == 2 ) { | |
| 61 TargetRate_bps -= REDUCE_BITRATE_10_MS_BPS; | |
| 62 } | |
| 63 | |
| 64 /* Find bitrate interval in table and interpolate */ | |
| 65 for( k = 1; k < TARGET_RATE_TAB_SZ; k++ ) { | |
| 66 if( TargetRate_bps <= rateTable[ k ] ) { | |
| 67 frac_Q6 = silk_DIV32( silk_LSHIFT( TargetRate_bps - rateTable[ k - 1 ], 6 ), | |
| 68 rateTable[ k ] - rateTable[ k - 1 ] ); | |
| 69 psEncC->SNR_dB_Q7 = silk_LSHIFT( silk_SNR_table_Q1[ k - 1 ], 6 ) + silk_MUL( frac_Q6, silk_SNR_table_Q1[ k ] - silk_SNR_table_Q1[ k - 1 ] ); | |
| 70 break; | |
| 71 } | |
| 72 } | |
| 73 | |
| 74 /* Reduce coding quality whenever LBRR is enabled, to free up some bits */ | |
| 75 if( psEncC->LBRR_enabled ) { | |
| 76 psEncC->SNR_dB_Q7 = silk_SMLABB( psEncC->SNR_dB_Q7, 12 - psEncC->LBRR_GainIncreases, SILK_FIX_CONST( -0.25, 7 ) ); | |
| 77 } | |
| 78 } | |
| 79 | |
| 80 return ret; | |
| 81 } |
