diff options
Diffstat (limited to 'lib/rbcodec/codecs/libopus/silk/HP_variable_cutoff.c')
-rw-r--r-- | lib/rbcodec/codecs/libopus/silk/HP_variable_cutoff.c | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/lib/rbcodec/codecs/libopus/silk/HP_variable_cutoff.c b/lib/rbcodec/codecs/libopus/silk/HP_variable_cutoff.c new file mode 100644 index 0000000000..bbe10f04ce --- /dev/null +++ b/lib/rbcodec/codecs/libopus/silk/HP_variable_cutoff.c | |||
@@ -0,0 +1,77 @@ | |||
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 | } | ||