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comparison: media/libopus/silk/HP_variable_cutoff.c
media/libopus/silk/HP_variable_cutoff.c
- branch
- TOR_BUG_9701
- changeset 15
- b8a032363ba2
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| -1:000000000000 | 0:3ed0b8a61f3b |
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| 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 #ifdef FIXED_POINT | |
| 32 #include "main_FIX.h" | |
| 33 #else | |
| 34 #include "main_FLP.h" | |
| 35 #endif | |
| 36 #include "tuning_parameters.h" | |
| 37 | |
| 38 /* High-pass filter with cutoff frequency adaptation based on pitch lag statistics */ | |
| 39 void silk_HP_variable_cutoff( | |
| 40 silk_encoder_state_Fxx state_Fxx[] /* I/O Encoder states */ | |
| 41 ) | |
| 42 { | |
| 43 opus_int quality_Q15; | |
| 44 opus_int32 pitch_freq_Hz_Q16, pitch_freq_log_Q7, delta_freq_Q7; | |
| 45 silk_encoder_state *psEncC1 = &state_Fxx[ 0 ].sCmn; | |
| 46 | |
| 47 /* Adaptive cutoff frequency: estimate low end of pitch frequency range */ | |
| 48 if( psEncC1->prevSignalType == TYPE_VOICED ) { | |
| 49 /* difference, in log domain */ | |
| 50 pitch_freq_Hz_Q16 = silk_DIV32_16( silk_LSHIFT( silk_MUL( psEncC1->fs_kHz, 1000 ), 16 ), psEncC1->prevLag ); | |
| 51 pitch_freq_log_Q7 = silk_lin2log( pitch_freq_Hz_Q16 ) - ( 16 << 7 ); | |
| 52 | |
| 53 /* adjustment based on quality */ | |
| 54 quality_Q15 = psEncC1->input_quality_bands_Q15[ 0 ]; | |
| 55 pitch_freq_log_Q7 = silk_SMLAWB( pitch_freq_log_Q7, silk_SMULWB( silk_LSHIFT( -quality_Q15, 2 ), quality_Q15 ), | |
| 56 pitch_freq_log_Q7 - ( silk_lin2log( SILK_FIX_CONST( VARIABLE_HP_MIN_CUTOFF_HZ, 16 ) ) - ( 16 << 7 ) ) ); | |
| 57 | |
| 58 /* delta_freq = pitch_freq_log - psEnc->variable_HP_smth1; */ | |
| 59 delta_freq_Q7 = pitch_freq_log_Q7 - silk_RSHIFT( psEncC1->variable_HP_smth1_Q15, 8 ); | |
| 60 if( delta_freq_Q7 < 0 ) { | |
| 61 /* less smoothing for decreasing pitch frequency, to track something close to the minimum */ | |
| 62 delta_freq_Q7 = silk_MUL( delta_freq_Q7, 3 ); | |
| 63 } | |
| 64 | |
| 65 /* limit delta, to reduce impact of outliers in pitch estimation */ | |
| 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 ) ); | |
| 67 | |
| 68 /* update smoother */ | |
| 69 psEncC1->variable_HP_smth1_Q15 = silk_SMLAWB( psEncC1->variable_HP_smth1_Q15, | |
| 70 silk_SMULBB( psEncC1->speech_activity_Q8, delta_freq_Q7 ), SILK_FIX_CONST( VARIABLE_HP_SMTH_COEF1, 16 ) ); | |
| 71 | |
| 72 /* limit frequency range */ | |
| 73 psEncC1->variable_HP_smth1_Q15 = silk_LIMIT_32( psEncC1->variable_HP_smth1_Q15, | |
| 74 silk_LSHIFT( silk_lin2log( VARIABLE_HP_MIN_CUTOFF_HZ ), 8 ), | |
| 75 silk_LSHIFT( silk_lin2log( VARIABLE_HP_MAX_CUTOFF_HZ ), 8 ) ); | |
| 76 } | |
| 77 } |
