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Diffstat (limited to 'lib/rbcodec/codecs/libopus/silk/VAD.c')
-rw-r--r-- | lib/rbcodec/codecs/libopus/silk/VAD.c | 360 |
1 files changed, 360 insertions, 0 deletions
diff --git a/lib/rbcodec/codecs/libopus/silk/VAD.c b/lib/rbcodec/codecs/libopus/silk/VAD.c new file mode 100644 index 0000000000..d0cda52162 --- /dev/null +++ b/lib/rbcodec/codecs/libopus/silk/VAD.c | |||
@@ -0,0 +1,360 @@ | |||
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.h" | ||
33 | #include "stack_alloc.h" | ||
34 | |||
35 | /* Silk VAD noise level estimation */ | ||
36 | # if !defined(OPUS_X86_MAY_HAVE_SSE4_1) | ||
37 | static OPUS_INLINE void silk_VAD_GetNoiseLevels( | ||
38 | const opus_int32 pX[ VAD_N_BANDS ], /* I subband energies */ | ||
39 | silk_VAD_state *psSilk_VAD /* I/O Pointer to Silk VAD state */ | ||
40 | ); | ||
41 | #endif | ||
42 | |||
43 | /**********************************/ | ||
44 | /* Initialization of the Silk VAD */ | ||
45 | /**********************************/ | ||
46 | opus_int silk_VAD_Init( /* O Return value, 0 if success */ | ||
47 | silk_VAD_state *psSilk_VAD /* I/O Pointer to Silk VAD state */ | ||
48 | ) | ||
49 | { | ||
50 | opus_int b, ret = 0; | ||
51 | |||
52 | /* reset state memory */ | ||
53 | silk_memset( psSilk_VAD, 0, sizeof( silk_VAD_state ) ); | ||
54 | |||
55 | /* init noise levels */ | ||
56 | /* Initialize array with approx pink noise levels (psd proportional to inverse of frequency) */ | ||
57 | for( b = 0; b < VAD_N_BANDS; b++ ) { | ||
58 | psSilk_VAD->NoiseLevelBias[ b ] = silk_max_32( silk_DIV32_16( VAD_NOISE_LEVELS_BIAS, b + 1 ), 1 ); | ||
59 | } | ||
60 | |||
61 | /* Initialize state */ | ||
62 | for( b = 0; b < VAD_N_BANDS; b++ ) { | ||
63 | psSilk_VAD->NL[ b ] = silk_MUL( 100, psSilk_VAD->NoiseLevelBias[ b ] ); | ||
64 | psSilk_VAD->inv_NL[ b ] = silk_DIV32( silk_int32_MAX, psSilk_VAD->NL[ b ] ); | ||
65 | } | ||
66 | psSilk_VAD->counter = 15; | ||
67 | |||
68 | /* init smoothed energy-to-noise ratio*/ | ||
69 | for( b = 0; b < VAD_N_BANDS; b++ ) { | ||
70 | psSilk_VAD->NrgRatioSmth_Q8[ b ] = 100 * 256; /* 100 * 256 --> 20 dB SNR */ | ||
71 | } | ||
72 | |||
73 | return( ret ); | ||
74 | } | ||
75 | |||
76 | /* Weighting factors for tilt measure */ | ||
77 | static const opus_int32 tiltWeights[ VAD_N_BANDS ] = { 30000, 6000, -12000, -12000 }; | ||
78 | |||
79 | /***************************************/ | ||
80 | /* Get the speech activity level in Q8 */ | ||
81 | /***************************************/ | ||
82 | opus_int silk_VAD_GetSA_Q8_c( /* O Return value, 0 if success */ | ||
83 | silk_encoder_state *psEncC, /* I/O Encoder state */ | ||
84 | const opus_int16 pIn[] /* I PCM input */ | ||
85 | ) | ||
86 | { | ||
87 | opus_int SA_Q15, pSNR_dB_Q7, input_tilt; | ||
88 | opus_int decimated_framelength1, decimated_framelength2; | ||
89 | opus_int decimated_framelength; | ||
90 | opus_int dec_subframe_length, dec_subframe_offset, SNR_Q7, i, b, s; | ||
91 | opus_int32 sumSquared, smooth_coef_Q16; | ||
92 | opus_int16 HPstateTmp; | ||
93 | VARDECL( opus_int16, X ); | ||
94 | opus_int32 Xnrg[ VAD_N_BANDS ]; | ||
95 | opus_int32 NrgToNoiseRatio_Q8[ VAD_N_BANDS ]; | ||
96 | opus_int32 speech_nrg, x_tmp; | ||
97 | opus_int X_offset[ VAD_N_BANDS ]; | ||
98 | opus_int ret = 0; | ||
99 | silk_VAD_state *psSilk_VAD = &psEncC->sVAD; | ||
100 | SAVE_STACK; | ||
101 | |||
102 | /* Safety checks */ | ||
103 | silk_assert( VAD_N_BANDS == 4 ); | ||
104 | celt_assert( MAX_FRAME_LENGTH >= psEncC->frame_length ); | ||
105 | celt_assert( psEncC->frame_length <= 512 ); | ||
106 | celt_assert( psEncC->frame_length == 8 * silk_RSHIFT( psEncC->frame_length, 3 ) ); | ||
107 | |||
108 | /***********************/ | ||
109 | /* Filter and Decimate */ | ||
110 | /***********************/ | ||
111 | decimated_framelength1 = silk_RSHIFT( psEncC->frame_length, 1 ); | ||
112 | decimated_framelength2 = silk_RSHIFT( psEncC->frame_length, 2 ); | ||
113 | decimated_framelength = silk_RSHIFT( psEncC->frame_length, 3 ); | ||
114 | /* Decimate into 4 bands: | ||
115 | 0 L 3L L 3L 5L | ||
116 | - -- - -- -- | ||
117 | 8 8 2 4 4 | ||
118 | |||
119 | [0-1 kHz| temp. |1-2 kHz| 2-4 kHz | 4-8 kHz | | ||
120 | |||
121 | They're arranged to allow the minimal ( frame_length / 4 ) extra | ||
122 | scratch space during the downsampling process */ | ||
123 | X_offset[ 0 ] = 0; | ||
124 | X_offset[ 1 ] = decimated_framelength + decimated_framelength2; | ||
125 | X_offset[ 2 ] = X_offset[ 1 ] + decimated_framelength; | ||
126 | X_offset[ 3 ] = X_offset[ 2 ] + decimated_framelength2; | ||
127 | ALLOC( X, X_offset[ 3 ] + decimated_framelength1, opus_int16 ); | ||
128 | |||
129 | /* 0-8 kHz to 0-4 kHz and 4-8 kHz */ | ||
130 | silk_ana_filt_bank_1( pIn, &psSilk_VAD->AnaState[ 0 ], | ||
131 | X, &X[ X_offset[ 3 ] ], psEncC->frame_length ); | ||
132 | |||
133 | /* 0-4 kHz to 0-2 kHz and 2-4 kHz */ | ||
134 | silk_ana_filt_bank_1( X, &psSilk_VAD->AnaState1[ 0 ], | ||
135 | X, &X[ X_offset[ 2 ] ], decimated_framelength1 ); | ||
136 | |||
137 | /* 0-2 kHz to 0-1 kHz and 1-2 kHz */ | ||
138 | silk_ana_filt_bank_1( X, &psSilk_VAD->AnaState2[ 0 ], | ||
139 | X, &X[ X_offset[ 1 ] ], decimated_framelength2 ); | ||
140 | |||
141 | /*********************************************/ | ||
142 | /* HP filter on lowest band (differentiator) */ | ||
143 | /*********************************************/ | ||
144 | X[ decimated_framelength - 1 ] = silk_RSHIFT( X[ decimated_framelength - 1 ], 1 ); | ||
145 | HPstateTmp = X[ decimated_framelength - 1 ]; | ||
146 | for( i = decimated_framelength - 1; i > 0; i-- ) { | ||
147 | X[ i - 1 ] = silk_RSHIFT( X[ i - 1 ], 1 ); | ||
148 | X[ i ] -= X[ i - 1 ]; | ||
149 | } | ||
150 | X[ 0 ] -= psSilk_VAD->HPstate; | ||
151 | psSilk_VAD->HPstate = HPstateTmp; | ||
152 | |||
153 | /*************************************/ | ||
154 | /* Calculate the energy in each band */ | ||
155 | /*************************************/ | ||
156 | for( b = 0; b < VAD_N_BANDS; b++ ) { | ||
157 | /* Find the decimated framelength in the non-uniformly divided bands */ | ||
158 | decimated_framelength = silk_RSHIFT( psEncC->frame_length, silk_min_int( VAD_N_BANDS - b, VAD_N_BANDS - 1 ) ); | ||
159 | |||
160 | /* Split length into subframe lengths */ | ||
161 | dec_subframe_length = silk_RSHIFT( decimated_framelength, VAD_INTERNAL_SUBFRAMES_LOG2 ); | ||
162 | dec_subframe_offset = 0; | ||
163 | |||
164 | /* Compute energy per sub-frame */ | ||
165 | /* initialize with summed energy of last subframe */ | ||
166 | Xnrg[ b ] = psSilk_VAD->XnrgSubfr[ b ]; | ||
167 | for( s = 0; s < VAD_INTERNAL_SUBFRAMES; s++ ) { | ||
168 | sumSquared = 0; | ||
169 | for( i = 0; i < dec_subframe_length; i++ ) { | ||
170 | /* The energy will be less than dec_subframe_length * ( silk_int16_MIN / 8 ) ^ 2. */ | ||
171 | /* Therefore we can accumulate with no risk of overflow (unless dec_subframe_length > 128) */ | ||
172 | x_tmp = silk_RSHIFT( | ||
173 | X[ X_offset[ b ] + i + dec_subframe_offset ], 3 ); | ||
174 | sumSquared = silk_SMLABB( sumSquared, x_tmp, x_tmp ); | ||
175 | |||
176 | /* Safety check */ | ||
177 | silk_assert( sumSquared >= 0 ); | ||
178 | } | ||
179 | |||
180 | /* Add/saturate summed energy of current subframe */ | ||
181 | if( s < VAD_INTERNAL_SUBFRAMES - 1 ) { | ||
182 | Xnrg[ b ] = silk_ADD_POS_SAT32( Xnrg[ b ], sumSquared ); | ||
183 | } else { | ||
184 | /* Look-ahead subframe */ | ||
185 | Xnrg[ b ] = silk_ADD_POS_SAT32( Xnrg[ b ], silk_RSHIFT( sumSquared, 1 ) ); | ||
186 | } | ||
187 | |||
188 | dec_subframe_offset += dec_subframe_length; | ||
189 | } | ||
190 | psSilk_VAD->XnrgSubfr[ b ] = sumSquared; | ||
191 | } | ||
192 | |||
193 | /********************/ | ||
194 | /* Noise estimation */ | ||
195 | /********************/ | ||
196 | silk_VAD_GetNoiseLevels( &Xnrg[ 0 ], psSilk_VAD ); | ||
197 | |||
198 | /***********************************************/ | ||
199 | /* Signal-plus-noise to noise ratio estimation */ | ||
200 | /***********************************************/ | ||
201 | sumSquared = 0; | ||
202 | input_tilt = 0; | ||
203 | for( b = 0; b < VAD_N_BANDS; b++ ) { | ||
204 | speech_nrg = Xnrg[ b ] - psSilk_VAD->NL[ b ]; | ||
205 | if( speech_nrg > 0 ) { | ||
206 | /* Divide, with sufficient resolution */ | ||
207 | if( ( Xnrg[ b ] & 0xFF800000 ) == 0 ) { | ||
208 | NrgToNoiseRatio_Q8[ b ] = silk_DIV32( silk_LSHIFT( Xnrg[ b ], 8 ), psSilk_VAD->NL[ b ] + 1 ); | ||
209 | } else { | ||
210 | NrgToNoiseRatio_Q8[ b ] = silk_DIV32( Xnrg[ b ], silk_RSHIFT( psSilk_VAD->NL[ b ], 8 ) + 1 ); | ||
211 | } | ||
212 | |||
213 | /* Convert to log domain */ | ||
214 | SNR_Q7 = silk_lin2log( NrgToNoiseRatio_Q8[ b ] ) - 8 * 128; | ||
215 | |||
216 | /* Sum-of-squares */ | ||
217 | sumSquared = silk_SMLABB( sumSquared, SNR_Q7, SNR_Q7 ); /* Q14 */ | ||
218 | |||
219 | /* Tilt measure */ | ||
220 | if( speech_nrg < ( (opus_int32)1 << 20 ) ) { | ||
221 | /* Scale down SNR value for small subband speech energies */ | ||
222 | SNR_Q7 = silk_SMULWB( silk_LSHIFT( silk_SQRT_APPROX( speech_nrg ), 6 ), SNR_Q7 ); | ||
223 | } | ||
224 | input_tilt = silk_SMLAWB( input_tilt, tiltWeights[ b ], SNR_Q7 ); | ||
225 | } else { | ||
226 | NrgToNoiseRatio_Q8[ b ] = 256; | ||
227 | } | ||
228 | } | ||
229 | |||
230 | /* Mean-of-squares */ | ||
231 | sumSquared = silk_DIV32_16( sumSquared, VAD_N_BANDS ); /* Q14 */ | ||
232 | |||
233 | /* Root-mean-square approximation, scale to dBs, and write to output pointer */ | ||
234 | pSNR_dB_Q7 = (opus_int16)( 3 * silk_SQRT_APPROX( sumSquared ) ); /* Q7 */ | ||
235 | |||
236 | /*********************************/ | ||
237 | /* Speech Probability Estimation */ | ||
238 | /*********************************/ | ||
239 | SA_Q15 = silk_sigm_Q15( silk_SMULWB( VAD_SNR_FACTOR_Q16, pSNR_dB_Q7 ) - VAD_NEGATIVE_OFFSET_Q5 ); | ||
240 | |||
241 | /**************************/ | ||
242 | /* Frequency Tilt Measure */ | ||
243 | /**************************/ | ||
244 | psEncC->input_tilt_Q15 = silk_LSHIFT( silk_sigm_Q15( input_tilt ) - 16384, 1 ); | ||
245 | |||
246 | /**************************************************/ | ||
247 | /* Scale the sigmoid output based on power levels */ | ||
248 | /**************************************************/ | ||
249 | speech_nrg = 0; | ||
250 | for( b = 0; b < VAD_N_BANDS; b++ ) { | ||
251 | /* Accumulate signal-without-noise energies, higher frequency bands have more weight */ | ||
252 | speech_nrg += ( b + 1 ) * silk_RSHIFT( Xnrg[ b ] - psSilk_VAD->NL[ b ], 4 ); | ||
253 | } | ||
254 | |||
255 | if( psEncC->frame_length == 20 * psEncC->fs_kHz ) { | ||
256 | speech_nrg = silk_RSHIFT32( speech_nrg, 1 ); | ||
257 | } | ||
258 | /* Power scaling */ | ||
259 | if( speech_nrg <= 0 ) { | ||
260 | SA_Q15 = silk_RSHIFT( SA_Q15, 1 ); | ||
261 | } else if( speech_nrg < 16384 ) { | ||
262 | speech_nrg = silk_LSHIFT32( speech_nrg, 16 ); | ||
263 | |||
264 | /* square-root */ | ||
265 | speech_nrg = silk_SQRT_APPROX( speech_nrg ); | ||
266 | SA_Q15 = silk_SMULWB( 32768 + speech_nrg, SA_Q15 ); | ||
267 | } | ||
268 | |||
269 | /* Copy the resulting speech activity in Q8 */ | ||
270 | psEncC->speech_activity_Q8 = silk_min_int( silk_RSHIFT( SA_Q15, 7 ), silk_uint8_MAX ); | ||
271 | |||
272 | /***********************************/ | ||
273 | /* Energy Level and SNR estimation */ | ||
274 | /***********************************/ | ||
275 | /* Smoothing coefficient */ | ||
276 | smooth_coef_Q16 = silk_SMULWB( VAD_SNR_SMOOTH_COEF_Q18, silk_SMULWB( (opus_int32)SA_Q15, SA_Q15 ) ); | ||
277 | |||
278 | if( psEncC->frame_length == 10 * psEncC->fs_kHz ) { | ||
279 | smooth_coef_Q16 >>= 1; | ||
280 | } | ||
281 | |||
282 | for( b = 0; b < VAD_N_BANDS; b++ ) { | ||
283 | /* compute smoothed energy-to-noise ratio per band */ | ||
284 | psSilk_VAD->NrgRatioSmth_Q8[ b ] = silk_SMLAWB( psSilk_VAD->NrgRatioSmth_Q8[ b ], | ||
285 | NrgToNoiseRatio_Q8[ b ] - psSilk_VAD->NrgRatioSmth_Q8[ b ], smooth_coef_Q16 ); | ||
286 | |||
287 | /* signal to noise ratio in dB per band */ | ||
288 | SNR_Q7 = 3 * ( silk_lin2log( psSilk_VAD->NrgRatioSmth_Q8[b] ) - 8 * 128 ); | ||
289 | /* quality = sigmoid( 0.25 * ( SNR_dB - 16 ) ); */ | ||
290 | psEncC->input_quality_bands_Q15[ b ] = silk_sigm_Q15( silk_RSHIFT( SNR_Q7 - 16 * 128, 4 ) ); | ||
291 | } | ||
292 | |||
293 | RESTORE_STACK; | ||
294 | return( ret ); | ||
295 | } | ||
296 | |||
297 | /**************************/ | ||
298 | /* Noise level estimation */ | ||
299 | /**************************/ | ||
300 | # if !defined(OPUS_X86_MAY_HAVE_SSE4_1) | ||
301 | static OPUS_INLINE | ||
302 | #endif | ||
303 | void silk_VAD_GetNoiseLevels( | ||
304 | const opus_int32 pX[ VAD_N_BANDS ], /* I subband energies */ | ||
305 | silk_VAD_state *psSilk_VAD /* I/O Pointer to Silk VAD state */ | ||
306 | ) | ||
307 | { | ||
308 | opus_int k; | ||
309 | opus_int32 nl, nrg, inv_nrg; | ||
310 | opus_int coef, min_coef; | ||
311 | |||
312 | /* Initially faster smoothing */ | ||
313 | if( psSilk_VAD->counter < 1000 ) { /* 1000 = 20 sec */ | ||
314 | min_coef = silk_DIV32_16( silk_int16_MAX, silk_RSHIFT( psSilk_VAD->counter, 4 ) + 1 ); | ||
315 | /* Increment frame counter */ | ||
316 | psSilk_VAD->counter++; | ||
317 | } else { | ||
318 | min_coef = 0; | ||
319 | } | ||
320 | |||
321 | for( k = 0; k < VAD_N_BANDS; k++ ) { | ||
322 | /* Get old noise level estimate for current band */ | ||
323 | nl = psSilk_VAD->NL[ k ]; | ||
324 | silk_assert( nl >= 0 ); | ||
325 | |||
326 | /* Add bias */ | ||
327 | nrg = silk_ADD_POS_SAT32( pX[ k ], psSilk_VAD->NoiseLevelBias[ k ] ); | ||
328 | silk_assert( nrg > 0 ); | ||
329 | |||
330 | /* Invert energies */ | ||
331 | inv_nrg = silk_DIV32( silk_int32_MAX, nrg ); | ||
332 | silk_assert( inv_nrg >= 0 ); | ||
333 | |||
334 | /* Less update when subband energy is high */ | ||
335 | if( nrg > silk_LSHIFT( nl, 3 ) ) { | ||
336 | coef = VAD_NOISE_LEVEL_SMOOTH_COEF_Q16 >> 3; | ||
337 | } else if( nrg < nl ) { | ||
338 | coef = VAD_NOISE_LEVEL_SMOOTH_COEF_Q16; | ||
339 | } else { | ||
340 | coef = silk_SMULWB( silk_SMULWW( inv_nrg, nl ), VAD_NOISE_LEVEL_SMOOTH_COEF_Q16 << 1 ); | ||
341 | } | ||
342 | |||
343 | /* Initially faster smoothing */ | ||
344 | coef = silk_max_int( coef, min_coef ); | ||
345 | |||
346 | /* Smooth inverse energies */ | ||
347 | psSilk_VAD->inv_NL[ k ] = silk_SMLAWB( psSilk_VAD->inv_NL[ k ], inv_nrg - psSilk_VAD->inv_NL[ k ], coef ); | ||
348 | silk_assert( psSilk_VAD->inv_NL[ k ] >= 0 ); | ||
349 | |||
350 | /* Compute noise level by inverting again */ | ||
351 | nl = silk_DIV32( silk_int32_MAX, psSilk_VAD->inv_NL[ k ] ); | ||
352 | silk_assert( nl >= 0 ); | ||
353 | |||
354 | /* Limit noise levels (guarantee 7 bits of head room) */ | ||
355 | nl = silk_min( nl, 0x00FFFFFF ); | ||
356 | |||
357 | /* Store as part of state */ | ||
358 | psSilk_VAD->NL[ k ] = nl; | ||
359 | } | ||
360 | } | ||