media/libopus/silk/HP_variable_cutoff.c@6474c204b198 (annotated)
media/libopus/silk/HP_variable_cutoff.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 | #ifdef FIXED_POINT |
| michael@0 | 32 | #include "main_FIX.h" |
| michael@0 | 33 | #else |
| michael@0 | 34 | #include "main_FLP.h" |
| michael@0 | 35 | #endif |
| michael@0 | 36 | #include "tuning_parameters.h" |
| michael@0 | 37 | |
| michael@0 | 38 | /* High-pass filter with cutoff frequency adaptation based on pitch lag statistics */ |
| michael@0 | 39 | void silk_HP_variable_cutoff( |
| michael@0 | 40 | silk_encoder_state_Fxx state_Fxx[] /* I/O Encoder states */ |
| michael@0 | 41 | ) |
| michael@0 | 42 | { |
| michael@0 | 43 | opus_int quality_Q15; |
| michael@0 | 44 | opus_int32 pitch_freq_Hz_Q16, pitch_freq_log_Q7, delta_freq_Q7; |
| michael@0 | 45 | silk_encoder_state *psEncC1 = &state_Fxx[ 0 ].sCmn; |
| michael@0 | 46 | |
| michael@0 | 47 | /* Adaptive cutoff frequency: estimate low end of pitch frequency range */ |
| michael@0 | 48 | if( psEncC1->prevSignalType == TYPE_VOICED ) { |
| michael@0 | 49 | /* difference, in log domain */ |
| michael@0 | 50 | pitch_freq_Hz_Q16 = silk_DIV32_16( silk_LSHIFT( silk_MUL( psEncC1->fs_kHz, 1000 ), 16 ), psEncC1->prevLag ); |
| michael@0 | 51 | pitch_freq_log_Q7 = silk_lin2log( pitch_freq_Hz_Q16 ) - ( 16 << 7 ); |
| michael@0 | 52 | |
| michael@0 | 53 | /* adjustment based on quality */ |
| michael@0 | 54 | quality_Q15 = psEncC1->input_quality_bands_Q15[ 0 ]; |
| michael@0 | 55 | pitch_freq_log_Q7 = silk_SMLAWB( pitch_freq_log_Q7, silk_SMULWB( silk_LSHIFT( -quality_Q15, 2 ), quality_Q15 ), |
| michael@0 | 56 | pitch_freq_log_Q7 - ( silk_lin2log( SILK_FIX_CONST( VARIABLE_HP_MIN_CUTOFF_HZ, 16 ) ) - ( 16 << 7 ) ) ); |
| michael@0 | 57 | |
| michael@0 | 58 | /* delta_freq = pitch_freq_log - psEnc->variable_HP_smth1; */ |
| michael@0 | 59 | delta_freq_Q7 = pitch_freq_log_Q7 - silk_RSHIFT( psEncC1->variable_HP_smth1_Q15, 8 ); |
| michael@0 | 60 | if( delta_freq_Q7 < 0 ) { |
| michael@0 | 61 | /* less smoothing for decreasing pitch frequency, to track something close to the minimum */ |
| michael@0 | 62 | delta_freq_Q7 = silk_MUL( delta_freq_Q7, 3 ); |
| michael@0 | 63 | } |
| michael@0 | 64 | |
| michael@0 | 65 | /* limit delta, to reduce impact of outliers in pitch estimation */ |
| michael@0 | 66 | delta_freq_Q7 = silk_LIMIT_32( delta_freq_Q7, -SILK_FIX_CONST( VARIABLE_HP_MAX_DELTA_FREQ, 7 ), SILK_FIX_CONST( VARIABLE_HP_MAX_DELTA_FREQ, 7 ) ); |
| michael@0 | 67 | |
| michael@0 | 68 | /* update smoother */ |
| michael@0 | 69 | psEncC1->variable_HP_smth1_Q15 = silk_SMLAWB( psEncC1->variable_HP_smth1_Q15, |
| michael@0 | 70 | silk_SMULBB( psEncC1->speech_activity_Q8, delta_freq_Q7 ), SILK_FIX_CONST( VARIABLE_HP_SMTH_COEF1, 16 ) ); |
| michael@0 | 71 | |
| michael@0 | 72 | /* limit frequency range */ |
| michael@0 | 73 | psEncC1->variable_HP_smth1_Q15 = silk_LIMIT_32( psEncC1->variable_HP_smth1_Q15, |
| michael@0 | 74 | silk_LSHIFT( silk_lin2log( VARIABLE_HP_MIN_CUTOFF_HZ ), 8 ), |
| michael@0 | 75 | silk_LSHIFT( silk_lin2log( VARIABLE_HP_MAX_CUTOFF_HZ ), 8 ) ); |
| michael@0 | 76 | } |
| michael@0 | 77 | } |
