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android / platform / external / webrtc / 4591fbd09f9cb6e83433c49a12dd8524c2806502 / . / webrtc / modules / audio_coding / codecs / cng / webrtc_cng.c
blob: 614a3df343a23f59bd25bdfff7e1157b82da0841 [file] [log] [blame]
/*
* Copyright (c) 2012 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.
*/
#include "webrtc_cng.h"
#include <string.h>
#include <stdlib.h>
#include "cng_helpfuns.h"
#include "signal_processing_library.h"
typedef struct WebRtcCngDecInst_t_ {
uint32_t dec_seed;
int32_t dec_target_energy;
int32_t dec_used_energy;
int16_t dec_target_reflCoefs[WEBRTC_CNG_MAX_LPC_ORDER + 1];
int16_t dec_used_reflCoefs[WEBRTC_CNG_MAX_LPC_ORDER + 1];
int16_t dec_filtstate[WEBRTC_CNG_MAX_LPC_ORDER + 1];
int16_t dec_filtstateLow[WEBRTC_CNG_MAX_LPC_ORDER + 1];
int16_t dec_Efiltstate[WEBRTC_CNG_MAX_LPC_ORDER + 1];
int16_t dec_EfiltstateLow[WEBRTC_CNG_MAX_LPC_ORDER + 1];
int16_t dec_order;
int16_t dec_target_scale_factor; /* Q29 */
int16_t dec_used_scale_factor; /* Q29 */
int16_t target_scale_factor; /* Q13 */
int16_t errorcode;
int16_t initflag;
} WebRtcCngDecInst_t;
typedef struct WebRtcCngEncInst_t_ {
int16_t enc_nrOfCoefs;
uint16_t enc_sampfreq;
int16_t enc_interval;
int16_t enc_msSinceSID;
int32_t enc_Energy;
int16_t enc_reflCoefs[WEBRTC_CNG_MAX_LPC_ORDER + 1];
int32_t enc_corrVector[WEBRTC_CNG_MAX_LPC_ORDER + 1];
uint32_t enc_seed;
int16_t errorcode;
int16_t initflag;
} WebRtcCngEncInst_t;
const int32_t WebRtcCng_kDbov[94] = {
1081109975, 858756178, 682134279, 541838517, 430397633, 341876992,
271562548, 215709799, 171344384, 136103682, 108110997, 85875618,
68213428, 54183852, 43039763, 34187699, 27156255, 21570980,
17134438, 13610368, 10811100, 8587562, 6821343, 5418385,
4303976, 3418770, 2715625, 2157098, 1713444, 1361037,
1081110, 858756, 682134, 541839, 430398, 341877,
271563, 215710, 171344, 136104, 108111, 85876,
68213, 54184, 43040, 34188, 27156, 21571,
17134, 13610, 10811, 8588, 6821, 5418,
4304, 3419, 2716, 2157, 1713, 1361,
1081, 859, 682, 542, 430, 342,
272, 216, 171, 136, 108, 86,
68, 54, 43, 34, 27, 22,
17, 14, 11, 9, 7, 5,
4, 3, 3, 2, 2, 1,
1, 1, 1, 1
};
const int16_t WebRtcCng_kCorrWindow[WEBRTC_CNG_MAX_LPC_ORDER] = {
32702, 32636, 32570, 32505, 32439, 32374,
32309, 32244, 32179, 32114, 32049, 31985
};
/****************************************************************************
* WebRtcCng_CreateEnc/Dec(...)
*
* These functions create an instance to the specified structure
*
* Input:
* - XXX_inst : Pointer to created instance that should be created
*
* Return value : 0 - Ok
* -1 - Error
*/
int16_t WebRtcCng_CreateEnc(CNG_enc_inst** cng_inst) {
if (cng_inst != NULL) {
*cng_inst = (CNG_enc_inst*) malloc(sizeof(WebRtcCngEncInst_t));
if (*cng_inst != NULL) {
(*(WebRtcCngEncInst_t**) cng_inst)->errorcode = 0;
(*(WebRtcCngEncInst_t**) cng_inst)->initflag = 0;
/* Needed to get the right function pointers in SPLIB. */
WebRtcSpl_Init();
return 0;
} else {
/* The memory could not be allocated. */
return -1;
}
} else {
/* The input pointer is invalid (NULL). */
return -1;
}
}
int16_t WebRtcCng_CreateDec(CNG_dec_inst** cng_inst) {
if (cng_inst != NULL ) {
*cng_inst = (CNG_dec_inst*) malloc(sizeof(WebRtcCngDecInst_t));
if (*cng_inst != NULL ) {
(*(WebRtcCngDecInst_t**) cng_inst)->errorcode = 0;
(*(WebRtcCngDecInst_t**) cng_inst)->initflag = 0;
/* Needed to get the right function pointers in SPLIB. */
WebRtcSpl_Init();
return 0;
} else {
/* The memory could not be allocated */
return -1;
}
} else {
/* The input pointer is invalid (NULL). */
return -1;
}
}
/****************************************************************************
* WebRtcCng_InitEnc/Dec(...)
*
* This function initializes a instance
*
* Input:
* - cng_inst : Instance that should be initialized
*
* - fs : 8000 for narrowband and 16000 for wideband
* - interval : generate SID data every interval ms
* - quality : TBD
*
* Output:
* - cng_inst : Initialized instance
*
* Return value : 0 - Ok
* -1 - Error
*/
int16_t WebRtcCng_InitEnc(CNG_enc_inst* cng_inst, uint16_t fs, int16_t interval,
int16_t quality) {
int i;
WebRtcCngEncInst_t* inst = (WebRtcCngEncInst_t*) cng_inst;
memset(inst, 0, sizeof(WebRtcCngEncInst_t));
/* Check LPC order */
if (quality > WEBRTC_CNG_MAX_LPC_ORDER || quality <= 0) {
inst->errorcode = CNG_DISALLOWED_LPC_ORDER;
return -1;
}
inst->enc_sampfreq = fs;
inst->enc_interval = interval;
inst->enc_nrOfCoefs = quality;
inst->enc_msSinceSID = 0;
inst->enc_seed = 7777; /* For debugging only. */
inst->enc_Energy = 0;
for (i = 0; i < (WEBRTC_CNG_MAX_LPC_ORDER + 1); i++) {
inst->enc_reflCoefs[i] = 0;
inst->enc_corrVector[i] = 0;
}
inst->initflag = 1;
return 0;
}
int16_t WebRtcCng_InitDec(CNG_dec_inst* cng_inst) {
int i;
WebRtcCngDecInst_t* inst = (WebRtcCngDecInst_t*) cng_inst;
memset(inst, 0, sizeof(WebRtcCngDecInst_t));
inst->dec_seed = 7777; /* For debugging only. */
inst->dec_order = 5;
inst->dec_target_scale_factor = 0;
inst->dec_used_scale_factor = 0;
for (i = 0; i < (WEBRTC_CNG_MAX_LPC_ORDER + 1); i++) {
inst->dec_filtstate[i] = 0;
inst->dec_target_reflCoefs[i] = 0;
inst->dec_used_reflCoefs[i] = 0;
}
inst->dec_target_reflCoefs[0] = 0;
inst->dec_used_reflCoefs[0] = 0;
inst->dec_used_energy = 0;
inst->initflag = 1;
return 0;
}
/****************************************************************************
* WebRtcCng_FreeEnc/Dec(...)
*
* These functions frees the dynamic memory of a specified instance
*
* Input:
* - cng_inst : Pointer to created instance that should be freed
*
* Return value : 0 - Ok
* -1 - Error
*/
int16_t WebRtcCng_FreeEnc(CNG_enc_inst* cng_inst) {
free(cng_inst);
return 0;
}
int16_t WebRtcCng_FreeDec(CNG_dec_inst* cng_inst) {
free(cng_inst);
return 0;
}
/****************************************************************************
* WebRtcCng_Encode(...)
*
* These functions analyzes background noise
*
* Input:
* - cng_inst : Pointer to created instance
* - speech : Signal (noise) to be analyzed
* - nrOfSamples : Size of speech vector
* - bytesOut : Nr of bytes to transmit, might be 0
*
* Return value : 0 - Ok
* -1 - Error
*/
int16_t WebRtcCng_Encode(CNG_enc_inst* cng_inst, int16_t* speech,
int16_t nrOfSamples, uint8_t* SIDdata,
int16_t* bytesOut, int16_t forceSID) {
WebRtcCngEncInst_t* inst = (WebRtcCngEncInst_t*) cng_inst;
int16_t arCoefs[WEBRTC_CNG_MAX_LPC_ORDER + 1];
int32_t corrVector[WEBRTC_CNG_MAX_LPC_ORDER + 1];
int16_t refCs[WEBRTC_CNG_MAX_LPC_ORDER + 1];
int16_t hanningW[WEBRTC_CNG_MAX_OUTSIZE_ORDER];
int16_t ReflBeta = 19661; /* 0.6 in q15. */
int16_t ReflBetaComp = 13107; /* 0.4 in q15. */
int32_t outEnergy;
int outShifts;
int i, stab;
int acorrScale;
int index;
int16_t ind, factor;
int32_t* bptr;
int32_t blo, bhi;
int16_t negate;
const int16_t* aptr;
int16_t speechBuf[WEBRTC_CNG_MAX_OUTSIZE_ORDER];
/* Check if encoder initiated. */
if (inst->initflag != 1) {
inst->errorcode = CNG_ENCODER_NOT_INITIATED;
return -1;
}
/* Check framesize. */
if (nrOfSamples > WEBRTC_CNG_MAX_OUTSIZE_ORDER) {
inst->errorcode = CNG_DISALLOWED_FRAME_SIZE;
return -1;
}
for (i = 0; i < nrOfSamples; i++) {
speechBuf[i] = speech[i];
}
factor = nrOfSamples;
/* Calculate energy and a coefficients. */
outEnergy = WebRtcSpl_Energy(speechBuf, nrOfSamples, &outShifts);
while (outShifts > 0) {
/* We can only do 5 shifts without destroying accuracy in
* division factor. */
if (outShifts > 5) {
outEnergy <<= (outShifts - 5);
outShifts = 5;
} else {
factor /= 2;
outShifts--;
}
}
outEnergy = WebRtcSpl_DivW32W16(outEnergy, factor);
if (outEnergy > 1) {
/* Create Hanning Window. */
WebRtcSpl_GetHanningWindow(hanningW, nrOfSamples / 2);
for (i = 0; i < (nrOfSamples / 2); i++)
hanningW[nrOfSamples - i - 1] = hanningW[i];
WebRtcSpl_ElementwiseVectorMult(speechBuf, hanningW, speechBuf, nrOfSamples,
14);
WebRtcSpl_AutoCorrelation(speechBuf, nrOfSamples, inst->enc_nrOfCoefs,
corrVector, &acorrScale);
if (*corrVector == 0)
*corrVector = WEBRTC_SPL_WORD16_MAX;
/* Adds the bandwidth expansion. */
aptr = WebRtcCng_kCorrWindow;
bptr = corrVector;
/* (zzz) lpc16_1 = 17+1+820+2+2 = 842 (ordo2=700). */
for (ind = 0; ind < inst->enc_nrOfCoefs; ind++) {
/* The below code multiplies the 16 b corrWindow values (Q15) with
* the 32 b corrvector (Q0) and shifts the result down 15 steps. */
negate = *bptr < 0;
if (negate)
*bptr = -*bptr;
blo = (int32_t) * aptr * (*bptr & 0xffff);
bhi = ((blo >> 16) & 0xffff)
+ ((int32_t)(*aptr++) * ((*bptr >> 16) & 0xffff));
blo = (blo & 0xffff) | ((bhi & 0xffff) << 16);
*bptr = (((bhi >> 16) & 0x7fff) << 17) | ((uint32_t) blo >> 15);
if (negate)
*bptr = -*bptr;
bptr++;
}
/* End of bandwidth expansion. */
stab = WebRtcSpl_LevinsonDurbin(corrVector, arCoefs, refCs,
inst->enc_nrOfCoefs);
if (!stab) {
/* Disregard from this frame */
*bytesOut = 0;
return 0;
}
} else {
for (i = 0; i < inst->enc_nrOfCoefs; i++)
refCs[i] = 0;
}
if (forceSID) {
/* Read instantaneous values instead of averaged. */
for (i = 0; i < inst->enc_nrOfCoefs; i++)
inst->enc_reflCoefs[i] = refCs[i];
inst->enc_Energy = outEnergy;
} else {
/* Average history with new values. */
for (i = 0; i < (inst->enc_nrOfCoefs); i++) {
inst->enc_reflCoefs[i] = (int16_t) WEBRTC_SPL_MUL_16_16_RSFT(
inst->enc_reflCoefs[i], ReflBeta, 15);
inst->enc_reflCoefs[i] += (int16_t) WEBRTC_SPL_MUL_16_16_RSFT(
refCs[i], ReflBetaComp, 15);
}
inst->enc_Energy = (outEnergy >> 2) + (inst->enc_Energy >> 1)
+ (inst->enc_Energy >> 2);
}
if (inst->enc_Energy < 1) {
inst->enc_Energy = 1;
}
if ((inst->enc_msSinceSID > (inst->enc_interval - 1)) || forceSID) {
/* Search for best dbov value. */
index = 0;
for (i = 1; i < 93; i++) {
/* Always round downwards. */
if ((inst->enc_Energy - WebRtcCng_kDbov[i]) > 0) {
index = i;
break;
}
}
if ((i == 93) && (index == 0))
index = 94;
SIDdata[0] = index;
/* Quantize coefficients with tweak for WebRtc implementation of RFC3389. */
if (inst->enc_nrOfCoefs == WEBRTC_CNG_MAX_LPC_ORDER) {
for (i = 0; i < inst->enc_nrOfCoefs; i++) {
/* Q15 to Q7 with rounding. */
SIDdata[i + 1] = ((inst->enc_reflCoefs[i] + 128) >> 8);
}
} else {
for (i = 0; i < inst->enc_nrOfCoefs; i++) {
/* Q15 to Q7 with rounding. */
SIDdata[i + 1] = (127 + ((inst->enc_reflCoefs[i] + 128) >> 8));
}
}
inst->enc_msSinceSID = 0;
*bytesOut = inst->enc_nrOfCoefs + 1;
inst->enc_msSinceSID += (1000 * nrOfSamples) / inst->enc_sampfreq;
return inst->enc_nrOfCoefs + 1;
} else {
inst->enc_msSinceSID += (1000 * nrOfSamples) / inst->enc_sampfreq;
*bytesOut = 0;
return 0;
}
}
/****************************************************************************
* WebRtcCng_UpdateSid(...)
*
* These functions updates the CN state, when a new SID packet arrives
*
* Input:
* - cng_inst : Pointer to created instance that should be freed
* - SID : SID packet, all headers removed
* - length : Length in bytes of SID packet
*
* Return value : 0 - Ok
* -1 - Error
*/
int16_t WebRtcCng_UpdateSid(CNG_dec_inst* cng_inst, uint8_t* SID,
size_t length) {
WebRtcCngDecInst_t* inst = (WebRtcCngDecInst_t*) cng_inst;
int16_t refCs[WEBRTC_CNG_MAX_LPC_ORDER];
int32_t targetEnergy;
int i;
if (inst->initflag != 1) {
inst->errorcode = CNG_DECODER_NOT_INITIATED;
return -1;
}
/* Throw away reflection coefficients of higher order than we can handle. */
if (length > (WEBRTC_CNG_MAX_LPC_ORDER + 1))
length = WEBRTC_CNG_MAX_LPC_ORDER + 1;
inst->dec_order = (int16_t)length - 1;
if (SID[0] > 93)
SID[0] = 93;
targetEnergy = WebRtcCng_kDbov[SID[0]];
/* Take down target energy to 75%. */
targetEnergy = targetEnergy >> 1;
targetEnergy += targetEnergy >> 2;
inst->dec_target_energy = targetEnergy;
/* Reconstruct coeffs with tweak for WebRtc implementation of RFC3389. */
if (inst->dec_order == WEBRTC_CNG_MAX_LPC_ORDER) {
for (i = 0; i < (inst->dec_order); i++) {
refCs[i] = SID[i + 1] << 8; /* Q7 to Q15*/
inst->dec_target_reflCoefs[i] = refCs[i];
}
} else {
for (i = 0; i < (inst->dec_order); i++) {
refCs[i] = (SID[i + 1] - 127) << 8; /* Q7 to Q15. */
inst->dec_target_reflCoefs[i] = refCs[i];
}
}
for (i = (inst->dec_order); i < WEBRTC_CNG_MAX_LPC_ORDER; i++) {
refCs[i] = 0;
inst->dec_target_reflCoefs[i] = refCs[i];
}
return 0;
}
/****************************************************************************
* WebRtcCng_Generate(...)
*
* These functions generates CN data when needed
*
* Input:
* - cng_inst : Pointer to created instance that should be freed
* - outData : pointer to area to write CN data
* - nrOfSamples : How much data to generate
*
* Return value : 0 - Ok
* -1 - Error
*/
int16_t WebRtcCng_Generate(CNG_dec_inst* cng_inst, int16_t* outData,
int16_t nrOfSamples, int16_t new_period) {
WebRtcCngDecInst_t* inst = (WebRtcCngDecInst_t*) cng_inst;
int i;
int16_t excitation[WEBRTC_CNG_MAX_OUTSIZE_ORDER];
int16_t low[WEBRTC_CNG_MAX_OUTSIZE_ORDER];
int16_t lpPoly[WEBRTC_CNG_MAX_LPC_ORDER + 1];
int16_t ReflBetaStd = 26214; /* 0.8 in q15. */
int16_t ReflBetaCompStd = 6553; /* 0.2 in q15. */
int16_t ReflBetaNewP = 19661; /* 0.6 in q15. */
int16_t ReflBetaCompNewP = 13107; /* 0.4 in q15. */
int16_t Beta, BetaC, tmp1, tmp2, tmp3;
int32_t targetEnergy;
int16_t En;
int16_t temp16;
if (nrOfSamples > WEBRTC_CNG_MAX_OUTSIZE_ORDER) {
inst->errorcode = CNG_DISALLOWED_FRAME_SIZE;
return -1;
}
if (new_period) {
inst->dec_used_scale_factor = inst->dec_target_scale_factor;
Beta = ReflBetaNewP;
BetaC = ReflBetaCompNewP;
} else {
Beta = ReflBetaStd;
BetaC = ReflBetaCompStd;
}
/* Here we use a 0.5 weighting, should possibly be modified to 0.6. */
tmp1 = inst->dec_used_scale_factor << 2; /* Q13->Q15 */
tmp2 = inst->dec_target_scale_factor << 2; /* Q13->Q15 */
tmp3 = (int16_t) WEBRTC_SPL_MUL_16_16_RSFT(tmp1, Beta, 15);
tmp3 += (int16_t) WEBRTC_SPL_MUL_16_16_RSFT(tmp2, BetaC, 15);
inst->dec_used_scale_factor = tmp3 >> 2; /* Q15->Q13 */
inst->dec_used_energy = inst->dec_used_energy >> 1;
inst->dec_used_energy += inst->dec_target_energy >> 1;
/* Do the same for the reflection coeffs. */
for (i = 0; i < WEBRTC_CNG_MAX_LPC_ORDER; i++) {
inst->dec_used_reflCoefs[i] = (int16_t) WEBRTC_SPL_MUL_16_16_RSFT(
inst->dec_used_reflCoefs[i], Beta, 15);
inst->dec_used_reflCoefs[i] += (int16_t) WEBRTC_SPL_MUL_16_16_RSFT(
inst->dec_target_reflCoefs[i], BetaC, 15);
}
/* Compute the polynomial coefficients. */
WebRtcCng_K2a16(inst->dec_used_reflCoefs, WEBRTC_CNG_MAX_LPC_ORDER, lpPoly);
targetEnergy = inst->dec_used_energy;
/* Calculate scaling factor based on filter energy. */
En = 8192; /* 1.0 in Q13. */
for (i = 0; i < (WEBRTC_CNG_MAX_LPC_ORDER); i++) {
/* Floating point value for reference.
E *= 1.0 - (inst->dec_used_reflCoefs[i] / 32768.0) *
(inst->dec_used_reflCoefs[i] / 32768.0);
*/
/* Same in fixed point. */
/* K(i).^2 in Q15. */
temp16 = (int16_t) WEBRTC_SPL_MUL_16_16_RSFT(
inst->dec_used_reflCoefs[i], inst->dec_used_reflCoefs[i], 15);
/* 1 - K(i).^2 in Q15. */
temp16 = 0x7fff - temp16;
En = (int16_t) WEBRTC_SPL_MUL_16_16_RSFT(En, temp16, 15);
}
/* float scaling= sqrt(E * inst->dec_target_energy / (1 << 24)); */
/* Calculate sqrt(En * target_energy / excitation energy) */
targetEnergy = WebRtcSpl_Sqrt(inst->dec_used_energy);
En = (int16_t) WebRtcSpl_Sqrt(En) << 6;
En = (En * 3) >> 1; /* 1.5 estimates sqrt(2). */
inst->dec_used_scale_factor = (int16_t)((En * targetEnergy) >> 12);
/* Generate excitation. */
/* Excitation energy per sample is 2.^24 - Q13 N(0,1). */
for (i = 0; i < nrOfSamples; i++) {
excitation[i] = WebRtcSpl_RandN(&inst->dec_seed) >> 1;
}
/* Scale to correct energy. */
WebRtcSpl_ScaleVector(excitation, excitation, inst->dec_used_scale_factor,
nrOfSamples, 13);
/* |lpPoly| - Coefficients in Q12.
* |excitation| - Speech samples.
* |nst->dec_filtstate| - State preservation.
* |outData| - Filtered speech samples. */
WebRtcSpl_FilterAR(lpPoly, WEBRTC_CNG_MAX_LPC_ORDER + 1, excitation,
nrOfSamples, inst->dec_filtstate, WEBRTC_CNG_MAX_LPC_ORDER,
inst->dec_filtstateLow, WEBRTC_CNG_MAX_LPC_ORDER, outData,
low, nrOfSamples);
return 0;
}
/****************************************************************************
* WebRtcCng_GetErrorCodeEnc/Dec(...)
*
* This functions can be used to check the error code of a CNG instance. When
* a function returns -1 a error code will be set for that instance. The
* function below extract the code of the last error that occured in the
* specified instance.
*
* Input:
* - CNG_inst : CNG enc/dec instance
*
* Return value : Error code
*/
int16_t WebRtcCng_GetErrorCodeEnc(CNG_enc_inst* cng_inst) {
/* Typecast pointer to real structure. */
WebRtcCngEncInst_t* inst = (WebRtcCngEncInst_t*) cng_inst;
return inst->errorcode;
}
int16_t WebRtcCng_GetErrorCodeDec(CNG_dec_inst* cng_inst) {
/* Typecast pointer to real structure. */
WebRtcCngDecInst_t* inst = (WebRtcCngDecInst_t*) cng_inst;
return inst->errorcode;
}