media/libopus/silk/control_SNR.c@6474c204b198 (annotated)
media/libopus/silk/control_SNR.c
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
| michael@0 | 1 | /*********************************************************************** |
| michael@0 | 2 | Copyright (c) 2006-2011, Skype Limited. All rights reserved. |
| michael@0 | 3 | Redistribution and use in source and binary forms, with or without |
| michael@0 | 4 | modification, are permitted provided that the following conditions |
| michael@0 | 5 | are met: |
| michael@0 | 6 | - Redistributions of source code must retain the above copyright notice, |
| michael@0 | 7 | this list of conditions and the following disclaimer. |
| michael@0 | 8 | - Redistributions in binary form must reproduce the above copyright |
| michael@0 | 9 | notice, this list of conditions and the following disclaimer in the |
| michael@0 | 10 | documentation and/or other materials provided with the distribution. |
| michael@0 | 11 | - Neither the name of Internet Society, IETF or IETF Trust, nor the |
| michael@0 | 12 | names of specific contributors, may be used to endorse or promote |
| michael@0 | 13 | products derived from this software without specific prior written |
| michael@0 | 14 | permission. |
| michael@0 | 15 | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| michael@0 | 16 | AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| michael@0 | 17 | IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| michael@0 | 18 | ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
| michael@0 | 19 | LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| michael@0 | 20 | CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| michael@0 | 21 | SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| michael@0 | 22 | INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| michael@0 | 23 | CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| michael@0 | 24 | ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| michael@0 | 25 | POSSIBILITY OF SUCH DAMAGE. |
| michael@0 | 26 | ***********************************************************************/ |
| michael@0 | 27 | |
| michael@0 | 28 | #ifdef HAVE_CONFIG_H |
| michael@0 | 29 | #include "config.h" |
| michael@0 | 30 | #endif |
| michael@0 | 31 | |
| michael@0 | 32 | #include "main.h" |
| michael@0 | 33 | #include "tuning_parameters.h" |
| michael@0 | 34 | |
| michael@0 | 35 | /* Control SNR of redidual quantizer */ |
| michael@0 | 36 | opus_int silk_control_SNR( |
| michael@0 | 37 | silk_encoder_state *psEncC, /* I/O Pointer to Silk encoder state */ |
| michael@0 | 38 | opus_int32 TargetRate_bps /* I Target max bitrate (bps) */ |
| michael@0 | 39 | ) |
| michael@0 | 40 | { |
| michael@0 | 41 | opus_int k, ret = SILK_NO_ERROR; |
| michael@0 | 42 | opus_int32 frac_Q6; |
| michael@0 | 43 | const opus_int32 *rateTable; |
| michael@0 | 44 | |
| michael@0 | 45 | /* Set bitrate/coding quality */ |
| michael@0 | 46 | TargetRate_bps = silk_LIMIT( TargetRate_bps, MIN_TARGET_RATE_BPS, MAX_TARGET_RATE_BPS ); |
| michael@0 | 47 | if( TargetRate_bps != psEncC->TargetRate_bps ) { |
| michael@0 | 48 | psEncC->TargetRate_bps = TargetRate_bps; |
| michael@0 | 49 | |
| michael@0 | 50 | /* If new TargetRate_bps, translate to SNR_dB value */ |
| michael@0 | 51 | if( psEncC->fs_kHz == 8 ) { |
| michael@0 | 52 | rateTable = silk_TargetRate_table_NB; |
| michael@0 | 53 | } else if( psEncC->fs_kHz == 12 ) { |
| michael@0 | 54 | rateTable = silk_TargetRate_table_MB; |
| michael@0 | 55 | } else { |
| michael@0 | 56 | rateTable = silk_TargetRate_table_WB; |
| michael@0 | 57 | } |
| michael@0 | 58 | |
| michael@0 | 59 | /* Reduce bitrate for 10 ms modes in these calculations */ |
| michael@0 | 60 | if( psEncC->nb_subfr == 2 ) { |
| michael@0 | 61 | TargetRate_bps -= REDUCE_BITRATE_10_MS_BPS; |
| michael@0 | 62 | } |
| michael@0 | 63 | |
| michael@0 | 64 | /* Find bitrate interval in table and interpolate */ |
| michael@0 | 65 | for( k = 1; k < TARGET_RATE_TAB_SZ; k++ ) { |
| michael@0 | 66 | if( TargetRate_bps <= rateTable[ k ] ) { |
| michael@0 | 67 | frac_Q6 = silk_DIV32( silk_LSHIFT( TargetRate_bps - rateTable[ k - 1 ], 6 ), |
| michael@0 | 68 | rateTable[ k ] - rateTable[ k - 1 ] ); |
| michael@0 | 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 ] ); |
| michael@0 | 70 | break; |
| michael@0 | 71 | } |
| michael@0 | 72 | } |
| michael@0 | 73 | |
| michael@0 | 74 | /* Reduce coding quality whenever LBRR is enabled, to free up some bits */ |
| michael@0 | 75 | if( psEncC->LBRR_enabled ) { |
| michael@0 | 76 | psEncC->SNR_dB_Q7 = silk_SMLABB( psEncC->SNR_dB_Q7, 12 - psEncC->LBRR_GainIncreases, SILK_FIX_CONST( -0.25, 7 ) ); |
| michael@0 | 77 | } |
| michael@0 | 78 | } |
| michael@0 | 79 | |
| michael@0 | 80 | return ret; |
| michael@0 | 81 | } |
