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Diffstat (limited to 'lib/rbcodec/codecs/libopus/silk/float/noise_shape_analysis_FLP.c')
-rw-r--r-- | lib/rbcodec/codecs/libopus/silk/float/noise_shape_analysis_FLP.c | 350 |
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diff --git a/lib/rbcodec/codecs/libopus/silk/float/noise_shape_analysis_FLP.c b/lib/rbcodec/codecs/libopus/silk/float/noise_shape_analysis_FLP.c new file mode 100644 index 0000000000..cb3d8a50b7 --- /dev/null +++ b/lib/rbcodec/codecs/libopus/silk/float/noise_shape_analysis_FLP.c | |||
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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 | |||
32 | #include "main_FLP.h" | ||
33 | #include "tuning_parameters.h" | ||
34 | |||
35 | /* Compute gain to make warped filter coefficients have a zero mean log frequency response on a */ | ||
36 | /* non-warped frequency scale. (So that it can be implemented with a minimum-phase monic filter.) */ | ||
37 | /* Note: A monic filter is one with the first coefficient equal to 1.0. In Silk we omit the first */ | ||
38 | /* coefficient in an array of coefficients, for monic filters. */ | ||
39 | static OPUS_INLINE silk_float warped_gain( | ||
40 | const silk_float *coefs, | ||
41 | silk_float lambda, | ||
42 | opus_int order | ||
43 | ) { | ||
44 | opus_int i; | ||
45 | silk_float gain; | ||
46 | |||
47 | lambda = -lambda; | ||
48 | gain = coefs[ order - 1 ]; | ||
49 | for( i = order - 2; i >= 0; i-- ) { | ||
50 | gain = lambda * gain + coefs[ i ]; | ||
51 | } | ||
52 | return (silk_float)( 1.0f / ( 1.0f - lambda * gain ) ); | ||
53 | } | ||
54 | |||
55 | /* Convert warped filter coefficients to monic pseudo-warped coefficients and limit maximum */ | ||
56 | /* amplitude of monic warped coefficients by using bandwidth expansion on the true coefficients */ | ||
57 | static OPUS_INLINE void warped_true2monic_coefs( | ||
58 | silk_float *coefs, | ||
59 | silk_float lambda, | ||
60 | silk_float limit, | ||
61 | opus_int order | ||
62 | ) { | ||
63 | opus_int i, iter, ind = 0; | ||
64 | silk_float tmp, maxabs, chirp, gain; | ||
65 | |||
66 | /* Convert to monic coefficients */ | ||
67 | for( i = order - 1; i > 0; i-- ) { | ||
68 | coefs[ i - 1 ] -= lambda * coefs[ i ]; | ||
69 | } | ||
70 | gain = ( 1.0f - lambda * lambda ) / ( 1.0f + lambda * coefs[ 0 ] ); | ||
71 | for( i = 0; i < order; i++ ) { | ||
72 | coefs[ i ] *= gain; | ||
73 | } | ||
74 | |||
75 | /* Limit */ | ||
76 | for( iter = 0; iter < 10; iter++ ) { | ||
77 | /* Find maximum absolute value */ | ||
78 | maxabs = -1.0f; | ||
79 | for( i = 0; i < order; i++ ) { | ||
80 | tmp = silk_abs_float( coefs[ i ] ); | ||
81 | if( tmp > maxabs ) { | ||
82 | maxabs = tmp; | ||
83 | ind = i; | ||
84 | } | ||
85 | } | ||
86 | if( maxabs <= limit ) { | ||
87 | /* Coefficients are within range - done */ | ||
88 | return; | ||
89 | } | ||
90 | |||
91 | /* Convert back to true warped coefficients */ | ||
92 | for( i = 1; i < order; i++ ) { | ||
93 | coefs[ i - 1 ] += lambda * coefs[ i ]; | ||
94 | } | ||
95 | gain = 1.0f / gain; | ||
96 | for( i = 0; i < order; i++ ) { | ||
97 | coefs[ i ] *= gain; | ||
98 | } | ||
99 | |||
100 | /* Apply bandwidth expansion */ | ||
101 | chirp = 0.99f - ( 0.8f + 0.1f * iter ) * ( maxabs - limit ) / ( maxabs * ( ind + 1 ) ); | ||
102 | silk_bwexpander_FLP( coefs, order, chirp ); | ||
103 | |||
104 | /* Convert to monic warped coefficients */ | ||
105 | for( i = order - 1; i > 0; i-- ) { | ||
106 | coefs[ i - 1 ] -= lambda * coefs[ i ]; | ||
107 | } | ||
108 | gain = ( 1.0f - lambda * lambda ) / ( 1.0f + lambda * coefs[ 0 ] ); | ||
109 | for( i = 0; i < order; i++ ) { | ||
110 | coefs[ i ] *= gain; | ||
111 | } | ||
112 | } | ||
113 | silk_assert( 0 ); | ||
114 | } | ||
115 | |||
116 | static OPUS_INLINE void limit_coefs( | ||
117 | silk_float *coefs, | ||
118 | silk_float limit, | ||
119 | opus_int order | ||
120 | ) { | ||
121 | opus_int i, iter, ind = 0; | ||
122 | silk_float tmp, maxabs, chirp; | ||
123 | |||
124 | for( iter = 0; iter < 10; iter++ ) { | ||
125 | /* Find maximum absolute value */ | ||
126 | maxabs = -1.0f; | ||
127 | for( i = 0; i < order; i++ ) { | ||
128 | tmp = silk_abs_float( coefs[ i ] ); | ||
129 | if( tmp > maxabs ) { | ||
130 | maxabs = tmp; | ||
131 | ind = i; | ||
132 | } | ||
133 | } | ||
134 | if( maxabs <= limit ) { | ||
135 | /* Coefficients are within range - done */ | ||
136 | return; | ||
137 | } | ||
138 | |||
139 | /* Apply bandwidth expansion */ | ||
140 | chirp = 0.99f - ( 0.8f + 0.1f * iter ) * ( maxabs - limit ) / ( maxabs * ( ind + 1 ) ); | ||
141 | silk_bwexpander_FLP( coefs, order, chirp ); | ||
142 | } | ||
143 | silk_assert( 0 ); | ||
144 | } | ||
145 | |||
146 | /* Compute noise shaping coefficients and initial gain values */ | ||
147 | void silk_noise_shape_analysis_FLP( | ||
148 | silk_encoder_state_FLP *psEnc, /* I/O Encoder state FLP */ | ||
149 | silk_encoder_control_FLP *psEncCtrl, /* I/O Encoder control FLP */ | ||
150 | const silk_float *pitch_res, /* I LPC residual from pitch analysis */ | ||
151 | const silk_float *x /* I Input signal [frame_length + la_shape] */ | ||
152 | ) | ||
153 | { | ||
154 | silk_shape_state_FLP *psShapeSt = &psEnc->sShape; | ||
155 | opus_int k, nSamples, nSegs; | ||
156 | silk_float SNR_adj_dB, HarmShapeGain, Tilt; | ||
157 | silk_float nrg, log_energy, log_energy_prev, energy_variation; | ||
158 | silk_float BWExp, gain_mult, gain_add, strength, b, warping; | ||
159 | silk_float x_windowed[ SHAPE_LPC_WIN_MAX ]; | ||
160 | silk_float auto_corr[ MAX_SHAPE_LPC_ORDER + 1 ]; | ||
161 | silk_float rc[ MAX_SHAPE_LPC_ORDER + 1 ]; | ||
162 | const silk_float *x_ptr, *pitch_res_ptr; | ||
163 | |||
164 | /* Point to start of first LPC analysis block */ | ||
165 | x_ptr = x - psEnc->sCmn.la_shape; | ||
166 | |||
167 | /****************/ | ||
168 | /* GAIN CONTROL */ | ||
169 | /****************/ | ||
170 | SNR_adj_dB = psEnc->sCmn.SNR_dB_Q7 * ( 1 / 128.0f ); | ||
171 | |||
172 | /* Input quality is the average of the quality in the lowest two VAD bands */ | ||
173 | psEncCtrl->input_quality = 0.5f * ( psEnc->sCmn.input_quality_bands_Q15[ 0 ] + psEnc->sCmn.input_quality_bands_Q15[ 1 ] ) * ( 1.0f / 32768.0f ); | ||
174 | |||
175 | /* Coding quality level, between 0.0 and 1.0 */ | ||
176 | psEncCtrl->coding_quality = silk_sigmoid( 0.25f * ( SNR_adj_dB - 20.0f ) ); | ||
177 | |||
178 | if( psEnc->sCmn.useCBR == 0 ) { | ||
179 | /* Reduce coding SNR during low speech activity */ | ||
180 | b = 1.0f - psEnc->sCmn.speech_activity_Q8 * ( 1.0f / 256.0f ); | ||
181 | SNR_adj_dB -= BG_SNR_DECR_dB * psEncCtrl->coding_quality * ( 0.5f + 0.5f * psEncCtrl->input_quality ) * b * b; | ||
182 | } | ||
183 | |||
184 | if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) { | ||
185 | /* Reduce gains for periodic signals */ | ||
186 | SNR_adj_dB += HARM_SNR_INCR_dB * psEnc->LTPCorr; | ||
187 | } else { | ||
188 | /* For unvoiced signals and low-quality input, adjust the quality slower than SNR_dB setting */ | ||
189 | SNR_adj_dB += ( -0.4f * psEnc->sCmn.SNR_dB_Q7 * ( 1 / 128.0f ) + 6.0f ) * ( 1.0f - psEncCtrl->input_quality ); | ||
190 | } | ||
191 | |||
192 | /*************************/ | ||
193 | /* SPARSENESS PROCESSING */ | ||
194 | /*************************/ | ||
195 | /* Set quantizer offset */ | ||
196 | if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) { | ||
197 | /* Initially set to 0; may be overruled in process_gains(..) */ | ||
198 | psEnc->sCmn.indices.quantOffsetType = 0; | ||
199 | } else { | ||
200 | /* Sparseness measure, based on relative fluctuations of energy per 2 milliseconds */ | ||
201 | nSamples = 2 * psEnc->sCmn.fs_kHz; | ||
202 | energy_variation = 0.0f; | ||
203 | log_energy_prev = 0.0f; | ||
204 | pitch_res_ptr = pitch_res; | ||
205 | nSegs = silk_SMULBB( SUB_FRAME_LENGTH_MS, psEnc->sCmn.nb_subfr ) / 2; | ||
206 | for( k = 0; k < nSegs; k++ ) { | ||
207 | nrg = ( silk_float )nSamples + ( silk_float )silk_energy_FLP( pitch_res_ptr, nSamples ); | ||
208 | log_energy = silk_log2( nrg ); | ||
209 | if( k > 0 ) { | ||
210 | energy_variation += silk_abs_float( log_energy - log_energy_prev ); | ||
211 | } | ||
212 | log_energy_prev = log_energy; | ||
213 | pitch_res_ptr += nSamples; | ||
214 | } | ||
215 | |||
216 | /* Set quantization offset depending on sparseness measure */ | ||
217 | if( energy_variation > ENERGY_VARIATION_THRESHOLD_QNT_OFFSET * (nSegs-1) ) { | ||
218 | psEnc->sCmn.indices.quantOffsetType = 0; | ||
219 | } else { | ||
220 | psEnc->sCmn.indices.quantOffsetType = 1; | ||
221 | } | ||
222 | } | ||
223 | |||
224 | /*******************************/ | ||
225 | /* Control bandwidth expansion */ | ||
226 | /*******************************/ | ||
227 | /* More BWE for signals with high prediction gain */ | ||
228 | strength = FIND_PITCH_WHITE_NOISE_FRACTION * psEncCtrl->predGain; /* between 0.0 and 1.0 */ | ||
229 | BWExp = BANDWIDTH_EXPANSION / ( 1.0f + strength * strength ); | ||
230 | |||
231 | /* Slightly more warping in analysis will move quantization noise up in frequency, where it's better masked */ | ||
232 | warping = (silk_float)psEnc->sCmn.warping_Q16 / 65536.0f + 0.01f * psEncCtrl->coding_quality; | ||
233 | |||
234 | /********************************************/ | ||
235 | /* Compute noise shaping AR coefs and gains */ | ||
236 | /********************************************/ | ||
237 | for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) { | ||
238 | /* Apply window: sine slope followed by flat part followed by cosine slope */ | ||
239 | opus_int shift, slope_part, flat_part; | ||
240 | flat_part = psEnc->sCmn.fs_kHz * 3; | ||
241 | slope_part = ( psEnc->sCmn.shapeWinLength - flat_part ) / 2; | ||
242 | |||
243 | silk_apply_sine_window_FLP( x_windowed, x_ptr, 1, slope_part ); | ||
244 | shift = slope_part; | ||
245 | silk_memcpy( x_windowed + shift, x_ptr + shift, flat_part * sizeof(silk_float) ); | ||
246 | shift += flat_part; | ||
247 | silk_apply_sine_window_FLP( x_windowed + shift, x_ptr + shift, 2, slope_part ); | ||
248 | |||
249 | /* Update pointer: next LPC analysis block */ | ||
250 | x_ptr += psEnc->sCmn.subfr_length; | ||
251 | |||
252 | if( psEnc->sCmn.warping_Q16 > 0 ) { | ||
253 | /* Calculate warped auto correlation */ | ||
254 | silk_warped_autocorrelation_FLP( auto_corr, x_windowed, warping, | ||
255 | psEnc->sCmn.shapeWinLength, psEnc->sCmn.shapingLPCOrder ); | ||
256 | } else { | ||
257 | /* Calculate regular auto correlation */ | ||
258 | silk_autocorrelation_FLP( auto_corr, x_windowed, psEnc->sCmn.shapeWinLength, psEnc->sCmn.shapingLPCOrder + 1 ); | ||
259 | } | ||
260 | |||
261 | /* Add white noise, as a fraction of energy */ | ||
262 | auto_corr[ 0 ] += auto_corr[ 0 ] * SHAPE_WHITE_NOISE_FRACTION + 1.0f; | ||
263 | |||
264 | /* Convert correlations to prediction coefficients, and compute residual energy */ | ||
265 | nrg = silk_schur_FLP( rc, auto_corr, psEnc->sCmn.shapingLPCOrder ); | ||
266 | silk_k2a_FLP( &psEncCtrl->AR[ k * MAX_SHAPE_LPC_ORDER ], rc, psEnc->sCmn.shapingLPCOrder ); | ||
267 | psEncCtrl->Gains[ k ] = ( silk_float )sqrt( nrg ); | ||
268 | |||
269 | if( psEnc->sCmn.warping_Q16 > 0 ) { | ||
270 | /* Adjust gain for warping */ | ||
271 | psEncCtrl->Gains[ k ] *= warped_gain( &psEncCtrl->AR[ k * MAX_SHAPE_LPC_ORDER ], warping, psEnc->sCmn.shapingLPCOrder ); | ||
272 | } | ||
273 | |||
274 | /* Bandwidth expansion for synthesis filter shaping */ | ||
275 | silk_bwexpander_FLP( &psEncCtrl->AR[ k * MAX_SHAPE_LPC_ORDER ], psEnc->sCmn.shapingLPCOrder, BWExp ); | ||
276 | |||
277 | if( psEnc->sCmn.warping_Q16 > 0 ) { | ||
278 | /* Convert to monic warped prediction coefficients and limit absolute values */ | ||
279 | warped_true2monic_coefs( &psEncCtrl->AR[ k * MAX_SHAPE_LPC_ORDER ], warping, 3.999f, psEnc->sCmn.shapingLPCOrder ); | ||
280 | } else { | ||
281 | /* Limit absolute values */ | ||
282 | limit_coefs( &psEncCtrl->AR[ k * MAX_SHAPE_LPC_ORDER ], 3.999f, psEnc->sCmn.shapingLPCOrder ); | ||
283 | } | ||
284 | } | ||
285 | |||
286 | /*****************/ | ||
287 | /* Gain tweaking */ | ||
288 | /*****************/ | ||
289 | /* Increase gains during low speech activity */ | ||
290 | gain_mult = (silk_float)pow( 2.0f, -0.16f * SNR_adj_dB ); | ||
291 | gain_add = (silk_float)pow( 2.0f, 0.16f * MIN_QGAIN_DB ); | ||
292 | for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) { | ||
293 | psEncCtrl->Gains[ k ] *= gain_mult; | ||
294 | psEncCtrl->Gains[ k ] += gain_add; | ||
295 | } | ||
296 | |||
297 | /************************************************/ | ||
298 | /* Control low-frequency shaping and noise tilt */ | ||
299 | /************************************************/ | ||
300 | /* Less low frequency shaping for noisy inputs */ | ||
301 | strength = LOW_FREQ_SHAPING * ( 1.0f + LOW_QUALITY_LOW_FREQ_SHAPING_DECR * ( psEnc->sCmn.input_quality_bands_Q15[ 0 ] * ( 1.0f / 32768.0f ) - 1.0f ) ); | ||
302 | strength *= psEnc->sCmn.speech_activity_Q8 * ( 1.0f / 256.0f ); | ||
303 | if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) { | ||
304 | /* Reduce low frequencies quantization noise for periodic signals, depending on pitch lag */ | ||
305 | /*f = 400; freqz([1, -0.98 + 2e-4 * f], [1, -0.97 + 7e-4 * f], 2^12, Fs); axis([0, 1000, -10, 1])*/ | ||
306 | for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) { | ||
307 | b = 0.2f / psEnc->sCmn.fs_kHz + 3.0f / psEncCtrl->pitchL[ k ]; | ||
308 | psEncCtrl->LF_MA_shp[ k ] = -1.0f + b; | ||
309 | psEncCtrl->LF_AR_shp[ k ] = 1.0f - b - b * strength; | ||
310 | } | ||
311 | Tilt = - HP_NOISE_COEF - | ||
312 | (1 - HP_NOISE_COEF) * HARM_HP_NOISE_COEF * psEnc->sCmn.speech_activity_Q8 * ( 1.0f / 256.0f ); | ||
313 | } else { | ||
314 | b = 1.3f / psEnc->sCmn.fs_kHz; | ||
315 | psEncCtrl->LF_MA_shp[ 0 ] = -1.0f + b; | ||
316 | psEncCtrl->LF_AR_shp[ 0 ] = 1.0f - b - b * strength * 0.6f; | ||
317 | for( k = 1; k < psEnc->sCmn.nb_subfr; k++ ) { | ||
318 | psEncCtrl->LF_MA_shp[ k ] = psEncCtrl->LF_MA_shp[ 0 ]; | ||
319 | psEncCtrl->LF_AR_shp[ k ] = psEncCtrl->LF_AR_shp[ 0 ]; | ||
320 | } | ||
321 | Tilt = -HP_NOISE_COEF; | ||
322 | } | ||
323 | |||
324 | /****************************/ | ||
325 | /* HARMONIC SHAPING CONTROL */ | ||
326 | /****************************/ | ||
327 | if( USE_HARM_SHAPING && psEnc->sCmn.indices.signalType == TYPE_VOICED ) { | ||
328 | /* Harmonic noise shaping */ | ||
329 | HarmShapeGain = HARMONIC_SHAPING; | ||
330 | |||
331 | /* More harmonic noise shaping for high bitrates or noisy input */ | ||
332 | HarmShapeGain += HIGH_RATE_OR_LOW_QUALITY_HARMONIC_SHAPING * | ||
333 | ( 1.0f - ( 1.0f - psEncCtrl->coding_quality ) * psEncCtrl->input_quality ); | ||
334 | |||
335 | /* Less harmonic noise shaping for less periodic signals */ | ||
336 | HarmShapeGain *= ( silk_float )sqrt( psEnc->LTPCorr ); | ||
337 | } else { | ||
338 | HarmShapeGain = 0.0f; | ||
339 | } | ||
340 | |||
341 | /*************************/ | ||
342 | /* Smooth over subframes */ | ||
343 | /*************************/ | ||
344 | for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) { | ||
345 | psShapeSt->HarmShapeGain_smth += SUBFR_SMTH_COEF * ( HarmShapeGain - psShapeSt->HarmShapeGain_smth ); | ||
346 | psEncCtrl->HarmShapeGain[ k ] = psShapeSt->HarmShapeGain_smth; | ||
347 | psShapeSt->Tilt_smth += SUBFR_SMTH_COEF * ( Tilt - psShapeSt->Tilt_smth ); | ||
348 | psEncCtrl->Tilt[ k ] = psShapeSt->Tilt_smth; | ||
349 | } | ||
350 | } | ||