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-rw-r--r--src/common_audio/vad/main/source/vad_filterbank.c267
1 files changed, 0 insertions, 267 deletions
diff --git a/src/common_audio/vad/main/source/vad_filterbank.c b/src/common_audio/vad/main/source/vad_filterbank.c
deleted file mode 100644
index 11392c917a..0000000000
--- a/src/common_audio/vad/main/source/vad_filterbank.c
+++ /dev/null
@@ -1,267 +0,0 @@
-/*
- * Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
- *
- * Use of this source code is governed by a BSD-style license
- * that can be found in the LICENSE file in the root of the source
- * tree. An additional intellectual property rights grant can be found
- * in the file PATENTS. All contributing project authors may
- * be found in the AUTHORS file in the root of the source tree.
- */
-
-
-/*
- * This file includes the implementation of the internal filterbank associated functions.
- * For function description, see vad_filterbank.h.
- */
-
-#include "vad_filterbank.h"
-#include "vad_defines.h"
-#include "vad_const.h"
-#include "signal_processing_library.h"
-
-void WebRtcVad_HpOutput(WebRtc_Word16 *in_vector,
- WebRtc_Word16 in_vector_length,
- WebRtc_Word16 *out_vector,
- WebRtc_Word16 *filter_state)
-{
- WebRtc_Word16 i, *pi, *outPtr;
- WebRtc_Word32 tmpW32;
-
- pi = &in_vector[0];
- outPtr = &out_vector[0];
-
- // The sum of the absolute values of the impulse response:
- // The zero/pole-filter has a max amplification of a single sample of: 1.4546
- // Impulse response: 0.4047 -0.6179 -0.0266 0.1993 0.1035 -0.0194
- // The all-zero section has a max amplification of a single sample of: 1.6189
- // Impulse response: 0.4047 -0.8094 0.4047 0 0 0
- // The all-pole section has a max amplification of a single sample of: 1.9931
- // Impulse response: 1.0000 0.4734 -0.1189 -0.2187 -0.0627 0.04532
-
- for (i = 0; i < in_vector_length; i++)
- {
- // all-zero section (filter coefficients in Q14)
- tmpW32 = (WebRtc_Word32)WEBRTC_SPL_MUL_16_16(kHpZeroCoefs[0], (*pi));
- tmpW32 += (WebRtc_Word32)WEBRTC_SPL_MUL_16_16(kHpZeroCoefs[1], filter_state[0]);
- tmpW32 += (WebRtc_Word32)WEBRTC_SPL_MUL_16_16(kHpZeroCoefs[2], filter_state[1]); // Q14
- filter_state[1] = filter_state[0];
- filter_state[0] = *pi++;
-
- // all-pole section
- tmpW32 -= (WebRtc_Word32)WEBRTC_SPL_MUL_16_16(kHpPoleCoefs[1], filter_state[2]); // Q14
- tmpW32 -= (WebRtc_Word32)WEBRTC_SPL_MUL_16_16(kHpPoleCoefs[2], filter_state[3]);
- filter_state[3] = filter_state[2];
- filter_state[2] = (WebRtc_Word16)WEBRTC_SPL_RSHIFT_W32 (tmpW32, 14);
- *outPtr++ = filter_state[2];
- }
-}
-
-void WebRtcVad_Allpass(WebRtc_Word16 *in_vector,
- WebRtc_Word16 *out_vector,
- WebRtc_Word16 filter_coefficients,
- int vector_length,
- WebRtc_Word16 *filter_state)
-{
- // The filter can only cause overflow (in the w16 output variable)
- // if more than 4 consecutive input numbers are of maximum value and
- // has the the same sign as the impulse responses first taps.
- // First 6 taps of the impulse response: 0.6399 0.5905 -0.3779
- // 0.2418 -0.1547 0.0990
-
- int n;
- WebRtc_Word16 tmp16;
- WebRtc_Word32 tmp32, in32, state32;
-
- state32 = WEBRTC_SPL_LSHIFT_W32(((WebRtc_Word32)(*filter_state)), 16); // Q31
-
- for (n = 0; n < vector_length; n++)
- {
-
- tmp32 = state32 + WEBRTC_SPL_MUL_16_16(filter_coefficients, (*in_vector));
- tmp16 = (WebRtc_Word16)WEBRTC_SPL_RSHIFT_W32(tmp32, 16);
- *out_vector++ = tmp16;
- in32 = WEBRTC_SPL_LSHIFT_W32(((WebRtc_Word32)(*in_vector)), 14);
- state32 = in32 - WEBRTC_SPL_MUL_16_16(filter_coefficients, tmp16);
- state32 = WEBRTC_SPL_LSHIFT_W32(state32, 1);
- in_vector += 2;
- }
-
- *filter_state = (WebRtc_Word16)WEBRTC_SPL_RSHIFT_W32(state32, 16);
-}
-
-void WebRtcVad_SplitFilter(WebRtc_Word16 *in_vector,
- WebRtc_Word16 *out_vector_hp,
- WebRtc_Word16 *out_vector_lp,
- WebRtc_Word16 *upper_state,
- WebRtc_Word16 *lower_state,
- int in_vector_length)
-{
- WebRtc_Word16 tmpOut;
- int k, halflen;
-
- // Downsampling by 2 and get two branches
- halflen = WEBRTC_SPL_RSHIFT_W16(in_vector_length, 1);
-
- // All-pass filtering upper branch
- WebRtcVad_Allpass(&in_vector[0], out_vector_hp, kAllPassCoefsQ15[0], halflen, upper_state);
-
- // All-pass filtering lower branch
- WebRtcVad_Allpass(&in_vector[1], out_vector_lp, kAllPassCoefsQ15[1], halflen, lower_state);
-
- // Make LP and HP signals
- for (k = 0; k < halflen; k++)
- {
- tmpOut = *out_vector_hp;
- *out_vector_hp++ -= *out_vector_lp;
- *out_vector_lp++ += tmpOut;
- }
-}
-
-WebRtc_Word16 WebRtcVad_get_features(VadInstT *inst,
- WebRtc_Word16 *in_vector,
- int frame_size,
- WebRtc_Word16 *out_vector)
-{
- int curlen, filtno;
- WebRtc_Word16 vecHP1[120], vecLP1[120];
- WebRtc_Word16 vecHP2[60], vecLP2[60];
- WebRtc_Word16 *ptin;
- WebRtc_Word16 *hptout, *lptout;
- WebRtc_Word16 power = 0;
-
- // Split at 2000 Hz and downsample
- filtno = 0;
- ptin = in_vector;
- hptout = vecHP1;
- lptout = vecLP1;
- curlen = frame_size;
- WebRtcVad_SplitFilter(ptin, hptout, lptout, &inst->upper_state[filtno],
- &inst->lower_state[filtno], curlen);
-
- // Split at 3000 Hz and downsample
- filtno = 1;
- ptin = vecHP1;
- hptout = vecHP2;
- lptout = vecLP2;
- curlen = WEBRTC_SPL_RSHIFT_W16(frame_size, 1);
-
- WebRtcVad_SplitFilter(ptin, hptout, lptout, &inst->upper_state[filtno],
- &inst->lower_state[filtno], curlen);
-
- // Energy in 3000 Hz - 4000 Hz
- curlen = WEBRTC_SPL_RSHIFT_W16(curlen, 1);
- WebRtcVad_LogOfEnergy(vecHP2, &out_vector[5], &power, kOffsetVector[5], curlen);
-
- // Energy in 2000 Hz - 3000 Hz
- WebRtcVad_LogOfEnergy(vecLP2, &out_vector[4], &power, kOffsetVector[4], curlen);
-
- // Split at 1000 Hz and downsample
- filtno = 2;
- ptin = vecLP1;
- hptout = vecHP2;
- lptout = vecLP2;
- curlen = WEBRTC_SPL_RSHIFT_W16(frame_size, 1);
- WebRtcVad_SplitFilter(ptin, hptout, lptout, &inst->upper_state[filtno],
- &inst->lower_state[filtno], curlen);
-
- // Energy in 1000 Hz - 2000 Hz
- curlen = WEBRTC_SPL_RSHIFT_W16(curlen, 1);
- WebRtcVad_LogOfEnergy(vecHP2, &out_vector[3], &power, kOffsetVector[3], curlen);
-
- // Split at 500 Hz
- filtno = 3;
- ptin = vecLP2;
- hptout = vecHP1;
- lptout = vecLP1;
-
- WebRtcVad_SplitFilter(ptin, hptout, lptout, &inst->upper_state[filtno],
- &inst->lower_state[filtno], curlen);
-
- // Energy in 500 Hz - 1000 Hz
- curlen = WEBRTC_SPL_RSHIFT_W16(curlen, 1);
- WebRtcVad_LogOfEnergy(vecHP1, &out_vector[2], &power, kOffsetVector[2], curlen);
- // Split at 250 Hz
- filtno = 4;
- ptin = vecLP1;
- hptout = vecHP2;
- lptout = vecLP2;
-
- WebRtcVad_SplitFilter(ptin, hptout, lptout, &inst->upper_state[filtno],
- &inst->lower_state[filtno], curlen);
-
- // Energy in 250 Hz - 500 Hz
- curlen = WEBRTC_SPL_RSHIFT_W16(curlen, 1);
- WebRtcVad_LogOfEnergy(vecHP2, &out_vector[1], &power, kOffsetVector[1], curlen);
-
- // Remove DC and LFs
- WebRtcVad_HpOutput(vecLP2, curlen, vecHP1, inst->hp_filter_state);
-
- // Power in 80 Hz - 250 Hz
- WebRtcVad_LogOfEnergy(vecHP1, &out_vector[0], &power, kOffsetVector[0], curlen);
-
- return power;
-}
-
-void WebRtcVad_LogOfEnergy(WebRtc_Word16 *vector,
- WebRtc_Word16 *enerlogval,
- WebRtc_Word16 *power,
- WebRtc_Word16 offset,
- int vector_length)
-{
- WebRtc_Word16 enerSum = 0;
- WebRtc_Word16 zeros, frac, log2;
- WebRtc_Word32 energy;
-
- int shfts = 0, shfts2;
-
- energy = WebRtcSpl_Energy(vector, vector_length, &shfts);
-
- if (energy > 0)
- {
-
- shfts2 = 16 - WebRtcSpl_NormW32(energy);
- shfts += shfts2;
- // "shfts" is the total number of right shifts that has been done to enerSum.
- enerSum = (WebRtc_Word16)WEBRTC_SPL_SHIFT_W32(energy, -shfts2);
-
- // Find:
- // 160*log10(enerSum*2^shfts) = 160*log10(2)*log2(enerSum*2^shfts) =
- // 160*log10(2)*(log2(enerSum) + log2(2^shfts)) =
- // 160*log10(2)*(log2(enerSum) + shfts)
-
- zeros = WebRtcSpl_NormU32(enerSum);
- frac = (WebRtc_Word16)(((WebRtc_UWord32)((WebRtc_Word32)(enerSum) << zeros)
- & 0x7FFFFFFF) >> 21);
- log2 = (WebRtc_Word16)(((31 - zeros) << 10) + frac);
-
- *enerlogval = (WebRtc_Word16)WEBRTC_SPL_MUL_16_16_RSFT(kLogConst, log2, 19)
- + (WebRtc_Word16)WEBRTC_SPL_MUL_16_16_RSFT(shfts, kLogConst, 9);
-
- if (*enerlogval < 0)
- {
- *enerlogval = 0;
- }
- } else
- {
- *enerlogval = 0;
- shfts = -15;
- enerSum = 0;
- }
-
- *enerlogval += offset;
-
- // Total power in frame
- if (*power <= MIN_ENERGY)
- {
- if (shfts > 0)
- {
- *power += MIN_ENERGY + 1;
- } else if (WEBRTC_SPL_SHIFT_W16(enerSum, shfts) > MIN_ENERGY)
- {
- *power += MIN_ENERGY + 1;
- } else
- {
- *power += WEBRTC_SPL_SHIFT_W16(enerSum, shfts);
- }
- }
-}
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