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ffmpeg/libavcodec/ilbcdec.c

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/*
* Copyright (c) 2013, The WebRTC project authors. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* * Neither the name of Google nor the names of its contributors may
* be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "libavutil/channel_layout.h"
#include "avcodec.h"
#include "internal.h"
#include "get_bits.h"
#include "ilbcdata.h"
#define LPC_N_20MS 1
#define LPC_N_30MS 2
#define LPC_N_MAX 2
#define LSF_NSPLIT 3
#define NASUB_MAX 4
#define LPC_FILTERORDER 10
#define NSUB_MAX 6
#define SUBL 40
#define ST_MEM_L_TBL 85
#define MEM_LF_TBL 147
#define STATE_SHORT_LEN_20MS 57
#define STATE_SHORT_LEN_30MS 58
#define BLOCKL_MAX 240
#define CB_MEML 147
#define CB_NSTAGES 3
#define CB_HALFFILTERLEN 4
#define CB_FILTERLEN 8
#define ENH_NBLOCKS_TOT 8
#define ENH_BLOCKL 80
#define ENH_BUFL (ENH_NBLOCKS_TOT)*ENH_BLOCKL
#define ENH_BUFL_FILTEROVERHEAD 3
#define BLOCKL_MAX 240
#define NSUB_20MS 4
#define NSUB_30MS 6
#define NSUB_MAX 6
#define NASUB_20MS 2
#define NASUB_30MS 4
#define NASUB_MAX 4
#define STATE_LEN 80
#define STATE_SHORT_LEN_30MS 58
#define STATE_SHORT_LEN_20MS 57
#define SPL_MUL_16_16(a, b) ((int32_t) (((int16_t)(a)) * ((int16_t)(b))))
#define SPL_MUL_16_16_RSFT(a, b, c) (SPL_MUL_16_16(a, b) >> (c))
typedef struct ILBCFrame {
int16_t lsf[LSF_NSPLIT*LPC_N_MAX];
int16_t cb_index[CB_NSTAGES*(NASUB_MAX + 1)];
int16_t gain_index[CB_NSTAGES*(NASUB_MAX + 1)];
int16_t ifm;
int16_t state_first;
int16_t idx[STATE_SHORT_LEN_30MS];
int16_t firstbits;
int16_t start;
} ILBCFrame;
typedef struct ILBCContext {
AVClass *class;
int enhancer;
int mode;
GetBitContext gb;
ILBCFrame frame;
int prev_enh_pl;
int consPLICount;
int last_lag;
int state_short_len;
int lpc_n;
int16_t nasub;
int16_t nsub;
int block_samples;
int16_t no_of_words;
int16_t no_of_bytes;
int16_t lsfdeq[LPC_FILTERORDER*LPC_N_MAX];
int16_t lsfold[LPC_FILTERORDER];
int16_t syntMem[LPC_FILTERORDER];
int16_t lsfdeqold[LPC_FILTERORDER];
int16_t weightdenum[(LPC_FILTERORDER + 1) * NSUB_MAX];
int16_t syntdenum[NSUB_MAX * (LPC_FILTERORDER + 1)];
int16_t old_syntdenum[NSUB_MAX * (LPC_FILTERORDER + 1)];
int16_t enh_buf[ENH_BUFL+ENH_BUFL_FILTEROVERHEAD];
int16_t enh_period[ENH_NBLOCKS_TOT];
int16_t prevResidual[NSUB_MAX*SUBL];
int16_t decresidual[BLOCKL_MAX];
int16_t plc_residual[BLOCKL_MAX + LPC_FILTERORDER];
int16_t seed;
int16_t prevPLI;
int16_t prevScale;
int16_t prevLag;
int16_t per_square;
int16_t prev_lpc[LPC_FILTERORDER + 1];
int16_t plc_lpc[LPC_FILTERORDER + 1];
int16_t hpimemx[2];
int16_t hpimemy[4];
} ILBCContext;
static int unpack_frame(ILBCContext *s)
{
ILBCFrame *frame = &s->frame;
GetBitContext *gb = &s->gb;
int j;
frame->lsf[0] = get_bits(gb, 6);
frame->lsf[1] = get_bits(gb, 7);
frame->lsf[2] = get_bits(gb, 7);
if (s->mode == 20) {
frame->start = get_bits(gb, 2);
frame->state_first = get_bits1(gb);
frame->ifm = get_bits(gb, 6);
frame->cb_index[0] = get_bits(gb, 6) << 1;
frame->gain_index[0] = get_bits(gb, 2) << 3;
frame->gain_index[1] = get_bits1(gb) << 3;
frame->cb_index[3] = get_bits(gb, 7) << 1;
frame->gain_index[3] = get_bits1(gb) << 4;
frame->gain_index[4] = get_bits1(gb) << 3;
frame->gain_index[6] = get_bits1(gb) << 4;
} else {
frame->lsf[3] = get_bits(gb, 6);
frame->lsf[4] = get_bits(gb, 7);
frame->lsf[5] = get_bits(gb, 7);
frame->start = get_bits(gb, 3);
frame->state_first = get_bits1(gb);
frame->ifm = get_bits(gb, 6);
frame->cb_index[0] = get_bits(gb, 4) << 3;
frame->gain_index[0] = get_bits1(gb) << 4;
frame->gain_index[1] = get_bits1(gb) << 3;
frame->cb_index[3] = get_bits(gb, 6) << 2;
frame->gain_index[3] = get_bits1(gb) << 4;
frame->gain_index[4] = get_bits1(gb) << 3;
}
for (j = 0; j < 48; j++)
frame->idx[j] = get_bits1(gb) << 2;
if (s->mode == 20) {
for (; j < 57; j++)
frame->idx[j] = get_bits1(gb) << 2;
frame->gain_index[1] |= get_bits1(gb) << 2;
frame->gain_index[3] |= get_bits(gb, 2) << 2;
frame->gain_index[4] |= get_bits1(gb) << 2;
frame->gain_index[6] |= get_bits1(gb) << 3;
frame->gain_index[7] = get_bits(gb, 2) << 2;
} else {
for (; j < 58; j++)
frame->idx[j] = get_bits1(gb) << 2;
frame->cb_index[0] |= get_bits(gb, 2) << 1;
frame->gain_index[0] |= get_bits1(gb) << 3;
frame->gain_index[1] |= get_bits1(gb) << 2;
frame->cb_index[3] |= get_bits1(gb) << 1;
frame->cb_index[6] = get_bits1(gb) << 7;
frame->cb_index[6] |= get_bits(gb, 6) << 1;
frame->cb_index[9] = get_bits(gb, 7) << 1;
frame->cb_index[12] = get_bits(gb, 3) << 5;
frame->cb_index[12] |= get_bits(gb, 4) << 1;
frame->gain_index[3] |= get_bits(gb, 2) << 2;
frame->gain_index[4] |= get_bits(gb, 2) << 1;
frame->gain_index[6] = get_bits(gb, 2) << 3;
frame->gain_index[7] = get_bits(gb, 2) << 2;
frame->gain_index[9] = get_bits1(gb) << 4;
frame->gain_index[10] = get_bits1(gb) << 3;
frame->gain_index[12] = get_bits1(gb) << 4;
frame->gain_index[13] = get_bits1(gb) << 3;
}
for (j = 0; j < 56; j++)
frame->idx[j] |= get_bits(gb, 2);
if (s->mode == 20) {
frame->idx[56] |= get_bits(gb, 2);
frame->cb_index[0] |= get_bits1(gb);
frame->cb_index[1] = get_bits(gb, 7);
frame->cb_index[2] = get_bits(gb, 6) << 1;
frame->cb_index[2] |= get_bits1(gb);
frame->gain_index[0] |= get_bits(gb, 3);
frame->gain_index[1] |= get_bits(gb, 2);
frame->gain_index[2] = get_bits(gb, 3);
frame->cb_index[3] |= get_bits1(gb);
frame->cb_index[4] = get_bits(gb, 6) << 1;
frame->cb_index[4] |= get_bits1(gb);
frame->cb_index[5] = get_bits(gb, 7);
frame->cb_index[6] = get_bits(gb, 8);
frame->cb_index[7] = get_bits(gb, 8);
frame->cb_index[8] = get_bits(gb, 8);
frame->gain_index[3] |= get_bits(gb, 2);
frame->gain_index[4] |= get_bits(gb, 2);
frame->gain_index[5] = get_bits(gb, 3);
frame->gain_index[6] |= get_bits(gb, 3);
frame->gain_index[7] |= get_bits(gb, 2);
frame->gain_index[8] = get_bits(gb, 3);
} else {
frame->idx[56] |= get_bits(gb, 2);
frame->idx[57] |= get_bits(gb, 2);
frame->cb_index[0] |= get_bits1(gb);
frame->cb_index[1] = get_bits(gb, 7);
frame->cb_index[2] = get_bits(gb, 4) << 3;
frame->cb_index[2] |= get_bits(gb, 3);
frame->gain_index[0] |= get_bits(gb, 3);
frame->gain_index[1] |= get_bits(gb, 2);
frame->gain_index[2] = get_bits(gb, 3);
frame->cb_index[3] |= get_bits1(gb);
frame->cb_index[4] = get_bits(gb, 4) << 3;
frame->cb_index[4] |= get_bits(gb, 3);
frame->cb_index[5] = get_bits(gb, 7);
frame->cb_index[6] |= get_bits1(gb);
frame->cb_index[7] = get_bits(gb, 5) << 3;
frame->cb_index[7] |= get_bits(gb, 3);
frame->cb_index[8] = get_bits(gb, 8);
frame->cb_index[9] |= get_bits1(gb);
frame->cb_index[10] = get_bits(gb, 4) << 4;
frame->cb_index[10] |= get_bits(gb, 4);
frame->cb_index[11] = get_bits(gb, 8);
frame->cb_index[12] |= get_bits1(gb);
frame->cb_index[13] = get_bits(gb, 3) << 5;
frame->cb_index[13] |= get_bits(gb, 5);
frame->cb_index[14] = get_bits(gb, 8);
frame->gain_index[3] |= get_bits(gb, 2);
frame->gain_index[4] |= get_bits1(gb);
frame->gain_index[5] = get_bits(gb, 3);
frame->gain_index[6] |= get_bits(gb, 3);
frame->gain_index[7] |= get_bits(gb, 2);
frame->gain_index[8] = get_bits(gb, 3);
frame->gain_index[9] |= get_bits(gb, 4);
frame->gain_index[10] |= get_bits1(gb) << 2;
frame->gain_index[10] |= get_bits(gb, 2);
frame->gain_index[11] = get_bits(gb, 3);
frame->gain_index[12] |= get_bits(gb, 4);
frame->gain_index[13] |= get_bits(gb, 3);
frame->gain_index[14] = get_bits(gb, 3);
}
return get_bits1(gb);
}
static void index_conv(int16_t *index)
{
int k;
for (k = 4; k < 6; k++) {
if (index[k] >= 44 && index[k] < 108) {
index[k] += 64;
} else if (index[k] >= 108 && index[k] < 128) {
index[k] += 128;
}
}
}
static void lsf_dequantization(int16_t *lsfdeq, int16_t *index, int16_t lpc_n)
{
int i, j, pos = 0, cb_pos = 0;
for (i = 0; i < LSF_NSPLIT; i++) {
for (j = 0; j < lsf_dim_codebook[i]; j++) {
lsfdeq[pos + j] = lsf_codebook[cb_pos + index[i] * lsf_dim_codebook[i] + j];
}
pos += lsf_dim_codebook[i];
cb_pos += lsf_size_codebook[i] * lsf_dim_codebook[i];
}
if (lpc_n > 1) {
pos = 0;
cb_pos = 0;
for (i = 0; i < LSF_NSPLIT; i++) {
for (j = 0; j < lsf_dim_codebook[i]; j++) {
lsfdeq[LPC_FILTERORDER + pos + j] = lsf_codebook[cb_pos +
index[LSF_NSPLIT + i] * lsf_dim_codebook[i] + j];
}
pos += lsf_dim_codebook[i];
cb_pos += lsf_size_codebook[i] * lsf_dim_codebook[i];
}
}
}
static void lsf_check_stability(int16_t *lsf, int dim, int nb_vectors)
{
for (int n = 0; n < 2; n++) {
for (int m = 0; m < nb_vectors; m++) {
for (int k = 0; k < dim - 1; k++) {
int i = m * dim + k;
if ((lsf[i + 1] - lsf[i]) < 319) {
if (lsf[i + 1] < lsf[i]) {
lsf[i + 1] = lsf[i] + 160;
lsf[i] = lsf[i + 1] - 160;
} else {
lsf[i] -= 160;
lsf[i + 1] += 160;
}
}
lsf[i] = av_clip(lsf[i], 82, 25723);
}
}
}
}
static void lsf_interpolate(int16_t *out, int16_t *in1,
int16_t *in2, int16_t coef,
int size)
{
int invcoef = 16384 - coef, i;
for (i = 0; i < size; i++)
out[i] = (coef * in1[i] + invcoef * in2[i] + 8192) >> 14;
}
static void lsf2lsp(int16_t *lsf, int16_t *lsp, int order)
{
int16_t diff, freq;
int32_t tmp;
int i, k;
for (i = 0; i < order; i++) {
freq = (lsf[i] * 20861) >> 15;
/* 20861: 1.0/(2.0*PI) in Q17 */
/*
Upper 8 bits give the index k and
Lower 8 bits give the difference, which needs
to be approximated linearly
*/
k = FFMIN(freq >> 8, 63);
diff = freq & 0xFF;
/* Calculate linear approximation */
tmp = cos_derivative_tbl[k] * diff;
lsp[i] = cos_tbl[k] + (tmp >> 12);
}
}
static void get_lsp_poly(int16_t *lsp, int32_t *f)
{
int16_t high, low;
int i, j, k, l;
int32_t tmp;
f[0] = 16777216;
f[1] = lsp[0] * -1024;
for (i = 2, k = 2, l = 2; i <= 5; i++, k += 2) {
f[l] = f[l - 2];
for (j = i; j > 1; j--, l--) {
high = f[l - 1] >> 16;
low = (f[l - 1] - (high * (1 << 16))) >> 1;
tmp = ((high * lsp[k]) * 4) + (((low * lsp[k]) >> 15) * 4);
f[l] += f[l - 2];
f[l] -= (unsigned)tmp;
}
f[l] -= lsp[k] * (1 << 10);
l += i;
}
}
static void lsf2poly(int16_t *a, int16_t *lsf)
{
int32_t f[2][6];
int16_t lsp[10];
int32_t tmp;
int i;
lsf2lsp(lsf, lsp, LPC_FILTERORDER);
get_lsp_poly(&lsp[0], f[0]);
get_lsp_poly(&lsp[1], f[1]);
for (i = 5; i > 0; i--) {
f[0][i] += (unsigned)f[0][i - 1];
f[1][i] -= (unsigned)f[1][i - 1];
}
a[0] = 4096;
for (i = 5; i > 0; i--) {
tmp = f[0][6 - i] + (unsigned)f[1][6 - i] + 4096;
a[6 - i] = tmp >> 13;
tmp = f[0][6 - i] - (unsigned)f[1][6 - i] + 4096;
a[5 + i] = tmp >> 13;
}
}
static void lsp_interpolate2polydec(int16_t *a, int16_t *lsf1,
int16_t *lsf2, int coef, int length)
{
int16_t lsftmp[LPC_FILTERORDER];
lsf_interpolate(lsftmp, lsf1, lsf2, coef, length);
lsf2poly(a, lsftmp);
}
static void bw_expand(int16_t *out, const int16_t *in, const int16_t *coef, int length)
{
int i;
out[0] = in[0];
for (i = 1; i < length; i++)
out[i] = (coef[i] * in[i] + 16384) >> 15;
}
static void lsp_interpolate(int16_t *syntdenum, int16_t *weightdenum,
int16_t *lsfdeq, int16_t length,
ILBCContext *s)
{
int16_t lp[LPC_FILTERORDER + 1], *lsfdeq2;
int i, pos, lp_length;
lsfdeq2 = lsfdeq + length;
lp_length = length + 1;
if (s->mode == 30) {
lsp_interpolate2polydec(lp, (*s).lsfdeqold, lsfdeq, lsf_weight_30ms[0], length);
memcpy(syntdenum, lp, lp_length * 2);
bw_expand(weightdenum, lp, kLpcChirpSyntDenum, lp_length);
pos = lp_length;
for (i = 1; i < 6; i++) {
lsp_interpolate2polydec(lp, lsfdeq, lsfdeq2,
lsf_weight_30ms[i],
length);
memcpy(syntdenum + pos, lp, lp_length * 2);
bw_expand(weightdenum + pos, lp, kLpcChirpSyntDenum, lp_length);
pos += lp_length;
}
} else {
pos = 0;
for (i = 0; i < s->nsub; i++) {
lsp_interpolate2polydec(lp, s->lsfdeqold, lsfdeq,
lsf_weight_20ms[i], length);
memcpy(syntdenum + pos, lp, lp_length * 2);
bw_expand(weightdenum + pos, lp, kLpcChirpSyntDenum, lp_length);
pos += lp_length;
}
}
if (s->mode == 30) {
memcpy(s->lsfdeqold, lsfdeq2, length * 2);
} else {
memcpy(s->lsfdeqold, lsfdeq, length * 2);
}
}
static void filter_mafq12(int16_t *in_ptr, int16_t *out_ptr,
int16_t *B, int16_t B_length,
int16_t length)
{
int o, i, j;
for (i = 0; i < length; i++) {
const int16_t *b_ptr = &B[0];
const int16_t *x_ptr = &in_ptr[i];
o = 0;
for (j = 0; j < B_length; j++)
o += b_ptr[j] * *x_ptr--;
o = av_clip(o, -134217728, 134215679);
out_ptr[i] = ((o + 2048) >> 12);
}
}
static void filter_arfq12(const int16_t *data_in,
int16_t *data_out,
const int16_t *coefficients,
int coefficients_length,
int data_length)
{
int i, j;
for (i = 0; i < data_length; i++) {
int output = 0, sum = 0;
for (j = coefficients_length - 1; j > 0; j--) {
sum += (unsigned)(coefficients[j] * data_out[i - j]);
}
output = coefficients[0] * data_in[i] - (unsigned)sum;
output = av_clip(output, -134217728, 134215679);
data_out[i] = (output + 2048) >> 12;
}
}
static void state_construct(int16_t ifm, int16_t *idx,
int16_t *synt_denum, int16_t *Out_fix,
int16_t len)
{
int k;
int16_t maxVal;
int16_t *tmp1, *tmp2, *tmp3;
/* Stack based */
int16_t numerator[1 + LPC_FILTERORDER];
int16_t sampleValVec[2 * STATE_SHORT_LEN_30MS + LPC_FILTERORDER];
int16_t sampleMaVec[2 * STATE_SHORT_LEN_30MS + LPC_FILTERORDER];
int16_t *sampleVal = &sampleValVec[LPC_FILTERORDER];
int16_t *sampleMa = &sampleMaVec[LPC_FILTERORDER];
int16_t *sampleAr = &sampleValVec[LPC_FILTERORDER];
/* initialization of coefficients */
for (k = 0; k < LPC_FILTERORDER + 1; k++) {
numerator[k] = synt_denum[LPC_FILTERORDER - k];
}
/* decoding of the maximum value */
maxVal = frg_quant_mod[ifm];
/* decoding of the sample values */
tmp1 = sampleVal;
tmp2 = &idx[len - 1];
if (ifm < 37) {
for (k = 0; k < len; k++) {
/*the shifting is due to the Q13 in sq4_fixQ13[i], also the adding of 2097152 (= 0.5 << 22)
maxVal is in Q8 and result is in Q(-1) */
(*tmp1) = (int16_t) ((SPL_MUL_16_16(maxVal, ilbc_state[(*tmp2)]) + 2097152) >> 22);
tmp1++;
tmp2--;
}
} else if (ifm < 59) {
for (k = 0; k < len; k++) {
/*the shifting is due to the Q13 in sq4_fixQ13[i], also the adding of 262144 (= 0.5 << 19)
maxVal is in Q5 and result is in Q(-1) */
(*tmp1) = (int16_t) ((SPL_MUL_16_16(maxVal, ilbc_state[(*tmp2)]) + 262144) >> 19);
tmp1++;
tmp2--;
}
} else {
for (k = 0; k < len; k++) {
/*the shifting is due to the Q13 in sq4_fixQ13[i], also the adding of 65536 (= 0.5 << 17)
maxVal is in Q3 and result is in Q(-1) */
(*tmp1) = (int16_t) ((SPL_MUL_16_16(maxVal, ilbc_state[(*tmp2)]) + 65536) >> 17);
tmp1++;
tmp2--;
}
}
/* Set the rest of the data to zero */
memset(&sampleVal[len], 0, len * 2);
/* circular convolution with all-pass filter */
/* Set the state to zero */
memset(sampleValVec, 0, LPC_FILTERORDER * 2);
/* Run MA filter + AR filter */
filter_mafq12(sampleVal, sampleMa, numerator, LPC_FILTERORDER + 1, len + LPC_FILTERORDER);
memset(&sampleMa[len + LPC_FILTERORDER], 0, (len - LPC_FILTERORDER) * 2);
filter_arfq12(sampleMa, sampleAr, synt_denum, LPC_FILTERORDER + 1, 2 * len);
tmp1 = &sampleAr[len - 1];
tmp2 = &sampleAr[2 * len - 1];
tmp3 = Out_fix;
for (k = 0; k < len; k++) {
(*tmp3) = (*tmp1) + (*tmp2);
tmp1--;
tmp2--;
tmp3++;
}
}
static int16_t gain_dequantization(int index, int max_in, int stage)
{
int16_t scale = FFMAX(1638, FFABS(max_in));
return ((scale * ilbc_gain[stage][index]) + 8192) >> 14;
}
static void vector_rmultiplication(int16_t *out, const int16_t *in,
const int16_t *win,
int length, int shift)
{
for (int i = 0; i < length; i++)
out[i] = (in[i] * win[-i]) >> shift;
}
static void vector_multiplication(int16_t *out, const int16_t *in,
const int16_t *win, int length,
int shift)
{
for (int i = 0; i < length; i++)
out[i] = (in[i] * win[i]) >> shift;
}
static void add_vector_and_shift(int16_t *out, const int16_t *in1,
const int16_t *in2, int length,
int shift)
{
for (int i = 0; i < length; i++)
out[i] = (in1[i] + in2[i]) >> shift;
}
static void create_augmented_vector(int index, int16_t *buffer, int16_t *cbVec)
{
int16_t cbVecTmp[4];
int interpolation_length = FFMIN(4, index);
int16_t ilow = index - interpolation_length;
memcpy(cbVec, buffer - index, index * 2);
vector_multiplication(&cbVec[ilow], buffer - index - interpolation_length, alpha, interpolation_length, 15);
vector_rmultiplication(cbVecTmp, buffer - interpolation_length, &alpha[interpolation_length - 1], interpolation_length, 15);
add_vector_and_shift(&cbVec[ilow], &cbVec[ilow], cbVecTmp, interpolation_length, 0);
memcpy(cbVec + index, buffer - index, FFMIN(SUBL - index, index) * sizeof(*cbVec));
}
static void get_codebook(int16_t * cbvec, /* (o) Constructed codebook vector */
int16_t * mem, /* (i) Codebook buffer */
int16_t index, /* (i) Codebook index */
int16_t lMem, /* (i) Length of codebook buffer */
int16_t cbveclen /* (i) Codebook vector length */
)
{
int16_t k, base_size;
int16_t lag;
/* Stack based */
int16_t tempbuff2[SUBL + 5];
/* Determine size of codebook sections */
base_size = lMem - cbveclen + 1;
if (cbveclen == SUBL) {
base_size += cbveclen / 2;
}
/* No filter -> First codebook section */
if (index < lMem - cbveclen + 1) {
/* first non-interpolated vectors */
k = index + cbveclen;
/* get vector */
memcpy(cbvec, mem + lMem - k, cbveclen * 2);
} else if (index < base_size) {
/* Calculate lag */
k = (int16_t) SPL_MUL_16_16(2, (index - (lMem - cbveclen + 1))) + cbveclen;
lag = k / 2;
create_augmented_vector(lag, mem + lMem, cbvec);
} else {
int16_t memIndTest;
/* first non-interpolated vectors */
if (index - base_size < lMem - cbveclen + 1) {
/* Set up filter memory, stuff zeros outside memory buffer */
memIndTest = lMem - (index - base_size + cbveclen);
memset(mem - CB_HALFFILTERLEN, 0, CB_HALFFILTERLEN * 2);
memset(mem + lMem, 0, CB_HALFFILTERLEN * 2);
/* do filtering to get the codebook vector */
filter_mafq12(&mem[memIndTest + 4], cbvec, (int16_t *) kCbFiltersRev, CB_FILTERLEN, cbveclen);
} else {
/* interpolated vectors */
/* Stuff zeros outside memory buffer */
memIndTest = lMem - cbveclen - CB_FILTERLEN;
memset(mem + lMem, 0, CB_HALFFILTERLEN * 2);
/* do filtering */
filter_mafq12(&mem[memIndTest + 7], tempbuff2, (int16_t *) kCbFiltersRev, CB_FILTERLEN, (int16_t) (cbveclen + 5));
/* Calculate lag index */
lag = (cbveclen << 1) - 20 + index - base_size - lMem - 1;
create_augmented_vector(lag, tempbuff2 + SUBL + 5, cbvec);
}
}
}
static void construct_vector (
int16_t *decvector, /* (o) Decoded vector */
int16_t *index, /* (i) Codebook indices */
int16_t *gain_index, /* (i) Gain quantization indices */
int16_t *mem, /* (i) Buffer for codevector construction */
int16_t lMem, /* (i) Length of buffer */
int16_t veclen)
{
int16_t gain[CB_NSTAGES];
int16_t cbvec0[SUBL];
int16_t cbvec1[SUBL];
int16_t cbvec2[SUBL];
unsigned a32;
int16_t *gainPtr;
int j;
/* gain de-quantization */
gain[0] = gain_dequantization(gain_index[0], 16384, 0);
gain[1] = gain_dequantization(gain_index[1], gain[0], 1);
gain[2] = gain_dequantization(gain_index[2], gain[1], 2);
/* codebook vector construction and construction of total vector */
/* Stack based */
get_codebook(cbvec0, mem, index[0], lMem, veclen);
get_codebook(cbvec1, mem, index[1], lMem, veclen);
get_codebook(cbvec2, mem, index[2], lMem, veclen);
gainPtr = &gain[0];
for (j = 0; j < veclen; j++) {
a32 = SPL_MUL_16_16(*gainPtr++, cbvec0[j]);
a32 += SPL_MUL_16_16(*gainPtr++, cbvec1[j]);
a32 += SPL_MUL_16_16(*gainPtr, cbvec2[j]);
gainPtr -= 2;
decvector[j] = (int)(a32 + 8192) >> 14;
}
}
static void reverse_memcpy(int16_t *dest, int16_t *source, int length)
{
int16_t* destPtr = dest;
int16_t* sourcePtr = source;
int j;
for (j = 0; j < length; j++)
*destPtr-- = *sourcePtr++;
}
static void decode_residual(ILBCContext *s,
ILBCFrame *encbits,
int16_t *decresidual,
int16_t *syntdenum)
{
int16_t meml_gotten, Nfor, Nback, diff, start_pos;
int16_t subcount, subframe;
int16_t *reverseDecresidual = s->enh_buf; /* Reversed decoded data, used for decoding backwards in time (reuse memory in state) */
int16_t *memVec = s->prevResidual;
int16_t *mem = &memVec[CB_HALFFILTERLEN]; /* Memory for codebook */
diff = STATE_LEN - s->state_short_len;
if (encbits->state_first == 1) {
start_pos = (encbits->start - 1) * SUBL;
} else {
start_pos = (encbits->start - 1) * SUBL + diff;
}
/* decode scalar part of start state */
state_construct(encbits->ifm, encbits->idx, &syntdenum[(encbits->start - 1) * (LPC_FILTERORDER + 1)], &decresidual[start_pos], s->state_short_len);
if (encbits->state_first) { /* put adaptive part in the end */
/* setup memory */
memset(mem, 0, (int16_t) (CB_MEML - s->state_short_len) * 2);
memcpy(mem + CB_MEML - s->state_short_len, decresidual + start_pos, s->state_short_len * 2);
/* construct decoded vector */
construct_vector(&decresidual[start_pos + s->state_short_len], encbits->cb_index, encbits->gain_index, mem + CB_MEML - ST_MEM_L_TBL, ST_MEM_L_TBL, (int16_t) diff);
} else { /* put adaptive part in the beginning */
/* setup memory */
meml_gotten = s->state_short_len;
reverse_memcpy(mem + CB_MEML - 1, decresidual + start_pos, meml_gotten);
memset(mem, 0, (int16_t) (CB_MEML - meml_gotten) * 2);
/* construct decoded vector */
construct_vector(reverseDecresidual, encbits->cb_index, encbits->gain_index, mem + CB_MEML - ST_MEM_L_TBL, ST_MEM_L_TBL, diff);
/* get decoded residual from reversed vector */
reverse_memcpy(&decresidual[start_pos - 1], reverseDecresidual, diff);
}
/* counter for predicted subframes */
subcount = 1;
/* forward prediction of subframes */
Nfor = s->nsub - encbits->start - 1;
if (Nfor > 0) {
/* setup memory */
memset(mem, 0, (CB_MEML - STATE_LEN) * 2);
memcpy(mem + CB_MEML - STATE_LEN, decresidual + (encbits->start - 1) * SUBL, STATE_LEN * 2);
/* loop over subframes to encode */
for (subframe = 0; subframe < Nfor; subframe++) {
/* construct decoded vector */
construct_vector(&decresidual[(encbits->start + 1 + subframe) * SUBL], encbits->cb_index + subcount * CB_NSTAGES, encbits->gain_index + subcount * CB_NSTAGES, mem, MEM_LF_TBL, SUBL);
/* update memory */
memmove(mem, mem + SUBL, (CB_MEML - SUBL) * sizeof(*mem));
memcpy(mem + CB_MEML - SUBL, &decresidual[(encbits->start + 1 + subframe) * SUBL], SUBL * 2);
subcount++;
}
}
/* backward prediction of subframes */
Nback = encbits->start - 1;
if (Nback > 0) {
/* setup memory */
meml_gotten = SUBL * (s->nsub + 1 - encbits->start);
if (meml_gotten > CB_MEML) {
meml_gotten = CB_MEML;
}
reverse_memcpy(mem + CB_MEML - 1, decresidual + (encbits->start - 1) * SUBL, meml_gotten);
memset(mem, 0, (int16_t) (CB_MEML - meml_gotten) * 2);
/* loop over subframes to decode */
for (subframe = 0; subframe < Nback; subframe++) {
/* construct decoded vector */
construct_vector(&reverseDecresidual[subframe * SUBL], encbits->cb_index + subcount * CB_NSTAGES,
encbits->gain_index + subcount * CB_NSTAGES, mem, MEM_LF_TBL, SUBL);
/* update memory */
memmove(mem, mem + SUBL, (CB_MEML - SUBL) * sizeof(*mem));
memcpy(mem + CB_MEML - SUBL, &reverseDecresidual[subframe * SUBL], SUBL * 2);
subcount++;
}
/* get decoded residual from reversed vector */
reverse_memcpy(decresidual + SUBL * Nback - 1, reverseDecresidual, SUBL * Nback);
}
}
static int16_t max_abs_value_w16(const int16_t* vector, int length)
{
int i = 0, absolute = 0, maximum = 0;
if (vector == NULL || length <= 0) {
return -1;
}
for (i = 0; i < length; i++) {
absolute = FFABS(vector[i]);
if (absolute > maximum)
maximum = absolute;
}
// Guard the case for abs(-32768).
return FFMIN(maximum, INT16_MAX);
}
static int16_t get_size_in_bits(uint32_t n)
{
int16_t bits;
if (0xFFFF0000 & n) {
bits = 16;
} else {
bits = 0;
}
if (0x0000FF00 & (n >> bits)) bits += 8;
if (0x000000F0 & (n >> bits)) bits += 4;
if (0x0000000C & (n >> bits)) bits += 2;
if (0x00000002 & (n >> bits)) bits += 1;
if (0x00000001 & (n >> bits)) bits += 1;
return bits;
}
static int32_t scale_dot_product(const int16_t *v1, const int16_t *v2, int length, int scaling)
{
int64_t sum = 0;
for (int i = 0; i < length; i++)
sum += (v1[i] * v2[i]) >> scaling;
return av_clipl_int32(sum);
}
static void correlation(int32_t *corr, int32_t *ener, int16_t *buffer,
int16_t lag, int16_t blen, int16_t srange, int16_t scale)
{
int16_t *w16ptr;
w16ptr = &buffer[blen - srange - lag];
*corr = scale_dot_product(&buffer[blen - srange], w16ptr, srange, scale);
*ener = scale_dot_product(w16ptr, w16ptr, srange, scale);
if (*ener == 0) {
*corr = 0;
*ener = 1;
}
}
#define SPL_SHIFT_W32(x, c) (((c) >= 0) ? ((x) << (c)) : ((x) >> (-(c))))
static int16_t norm_w32(int32_t a)
{
if (a == 0) {
return 0;
} else if (a < 0) {
a = ~a;
}
return ff_clz(a);
}
static int32_t div_w32_w16(int32_t num, int16_t den)
{
if (den != 0)
return num / den;
else
return 0x7FFFFFFF;
}
static void do_plc(int16_t *plc_residual, /* (o) concealed residual */
int16_t *plc_lpc, /* (o) concealed LP parameters */
int16_t PLI, /* (i) packet loss indicator
0 - no PL, 1 = PL */
int16_t *decresidual, /* (i) decoded residual */
int16_t *lpc, /* (i) decoded LPC (only used for no PL) */
int16_t inlag, /* (i) pitch lag */
ILBCContext *s) /* (i/o) decoder instance */
{
int16_t i, pick;
int32_t cross, ener, cross_comp, ener_comp = 0;
int32_t measure, max_measure, energy;
int16_t max, cross_square_max, cross_square;
int16_t j, lag, tmp1, tmp2, randlag;
int16_t shift1, shift2, shift3, shift_max;
int16_t scale3;
int16_t corrLen;
int32_t tmpW32, tmp2W32;
int16_t use_gain;
int16_t tot_gain;
int16_t max_perSquare;
int16_t scale1, scale2;
int16_t totscale;
int32_t nom;
int16_t denom;
int16_t pitchfact;
int16_t use_lag;
int ind;
int16_t randvec[BLOCKL_MAX];
/* Packet Loss */
if (PLI == 1) {
s->consPLICount += 1;
/* if previous frame not lost,
determine pitch pred. gain */
if (s->prevPLI != 1) {
/* Maximum 60 samples are correlated, preserve as high accuracy
as possible without getting overflow */
max = max_abs_value_w16(s->prevResidual, s->block_samples);
scale3 = (get_size_in_bits(max) << 1) - 25;
if (scale3 < 0) {
scale3 = 0;
}
/* Store scale for use when interpolating between the
* concealment and the received packet */
s->prevScale = scale3;
/* Search around the previous lag +/-3 to find the
best pitch period */
lag = inlag - 3;
/* Guard against getting outside the frame */
corrLen = FFMIN(60, s->block_samples - (inlag + 3));
correlation(&cross, &ener, s->prevResidual, lag, s->block_samples, corrLen, scale3);
/* Normalize and store cross^2 and the number of shifts */
shift_max = get_size_in_bits(FFABS(cross)) - 15;
cross_square_max = (int16_t) SPL_MUL_16_16_RSFT(SPL_SHIFT_W32(cross, -shift_max), SPL_SHIFT_W32(cross, -shift_max), 15);
for (j = inlag - 2; j <= inlag + 3; j++) {
correlation(&cross_comp, &ener_comp, s->prevResidual, j, s->block_samples, corrLen, scale3);
/* Use the criteria (corr*corr)/energy to compare if
this lag is better or not. To avoid the division,
do a cross multiplication */
shift1 = get_size_in_bits(FFABS(cross_comp)) - 15;
cross_square = (int16_t) SPL_MUL_16_16_RSFT(SPL_SHIFT_W32(cross_comp, -shift1), SPL_SHIFT_W32(cross_comp, -shift1), 15);
shift2 = get_size_in_bits(ener) - 15;
measure = SPL_MUL_16_16(SPL_SHIFT_W32(ener, -shift2), cross_square);
shift3 = get_size_in_bits(ener_comp) - 15;
max_measure = SPL_MUL_16_16(SPL_SHIFT_W32(ener_comp, -shift3), cross_square_max);
/* Calculate shift value, so that the two measures can
be put in the same Q domain */
if (((shift_max << 1) + shift3) > ((shift1 << 1) + shift2)) {
tmp1 = FFMIN(31, (shift_max << 1) + shift3 - (shift1 << 1) - shift2);
tmp2 = 0;
} else {
tmp1 = 0;
tmp2 = FFMIN(31, (shift1 << 1) + shift2 - (shift_max << 1) - shift3);
}
if ((measure >> tmp1) > (max_measure >> tmp2)) {
/* New lag is better => record lag, measure and domain */
lag = j;
cross_square_max = cross_square;
cross = cross_comp;
shift_max = shift1;
ener = ener_comp;
}
}
/* Calculate the periodicity for the lag with the maximum correlation.
Definition of the periodicity:
abs(corr(vec1, vec2))/(sqrt(energy(vec1))*sqrt(energy(vec2)))
Work in the Square domain to simplify the calculations
max_perSquare is less than 1 (in Q15)
*/
tmp2W32 = scale_dot_product(&s->prevResidual[s->block_samples - corrLen], &s->prevResidual[s->block_samples - corrLen], corrLen, scale3);
if ((tmp2W32 > 0) && (ener_comp > 0)) {
/* norm energies to int16_t, compute the product of the energies and
use the upper int16_t as the denominator */
scale1 = norm_w32(tmp2W32) - 16;
tmp1 = SPL_SHIFT_W32(tmp2W32, scale1);
scale2 = norm_w32(ener) - 16;
tmp2 = SPL_SHIFT_W32(ener, scale2);
denom = SPL_MUL_16_16_RSFT(tmp1, tmp2, 16); /* denom in Q(scale1+scale2-16) */
/* Square the cross correlation and norm it such that max_perSquare
will be in Q15 after the division */
totscale = scale1 + scale2 - 1;
tmp1 = SPL_SHIFT_W32(cross, (totscale >> 1));
tmp2 = SPL_SHIFT_W32(cross, totscale - (totscale >> 1));
nom = SPL_MUL_16_16(tmp1, tmp2);
max_perSquare = div_w32_w16(nom, denom);
} else {
max_perSquare = 0;
}
} else {
/* previous frame lost, use recorded lag and gain */
lag = s->prevLag;
max_perSquare = s->per_square;
}
/* Attenuate signal and scale down pitch pred gain if
several frames lost consecutively */
use_gain = 32767; /* 1.0 in Q15 */
if (s->consPLICount * s->block_samples > 320) {
use_gain = 29491; /* 0.9 in Q15 */
} else if (s->consPLICount * s->block_samples > 640) {
use_gain = 22938; /* 0.7 in Q15 */
} else if (s->consPLICount * s->block_samples > 960) {
use_gain = 16384; /* 0.5 in Q15 */
} else if (s->consPLICount * s->block_samples > 1280) {
use_gain = 0; /* 0.0 in Q15 */
}
/* Compute mixing factor of picth repeatition and noise:
for max_per>0.7 set periodicity to 1.0
0.4<max_per<0.7 set periodicity to (maxper-0.4)/0.7-0.4)
max_per<0.4 set periodicity to 0.0
*/
if (max_perSquare > 7868) { /* periodicity > 0.7 (0.7^4=0.2401 in Q15) */
pitchfact = 32767;
} else if (max_perSquare > 839) { /* 0.4 < periodicity < 0.7 (0.4^4=0.0256 in Q15) */
/* find best index and interpolate from that */
ind = 5;
while ((max_perSquare < kPlcPerSqr[ind]) && (ind > 0)) {
ind--;
}
/* pitch fact is approximated by first order */
tmpW32 = kPlcPitchFact[ind] + SPL_MUL_16_16_RSFT(kPlcPfSlope[ind], (max_perSquare - kPlcPerSqr[ind]), 11);
pitchfact = FFMIN(tmpW32, 32767); /* guard against overflow */
} else { /* periodicity < 0.4 */
pitchfact = 0;
}
/* avoid repetition of same pitch cycle (buzzyness) */
use_lag = lag;
if (lag < 80) {
use_lag = 2 * lag;
}
/* compute concealed residual */
energy = 0;
for (i = 0; i < s->block_samples; i++) {
/* noise component - 52 < randlagFIX < 117 */
s->seed = SPL_MUL_16_16(s->seed, 31821) + 13849;
randlag = 53 + (s->seed & 63);
pick = i - randlag;
if (pick < 0) {
randvec[i] = s->prevResidual[s->block_samples + pick];
} else {
randvec[i] = s->prevResidual[pick];
}
/* pitch repeatition component */
pick = i - use_lag;
if (pick < 0) {
plc_residual[i] = s->prevResidual[s->block_samples + pick];
} else {
plc_residual[i] = plc_residual[pick];
}
/* Attinuate total gain for each 10 ms */
if (i < 80) {
tot_gain = use_gain;
} else if (i < 160) {
tot_gain = SPL_MUL_16_16_RSFT(31130, use_gain, 15); /* 0.95*use_gain */
} else {
tot_gain = SPL_MUL_16_16_RSFT(29491, use_gain, 15); /* 0.9*use_gain */
}
/* mix noise and pitch repeatition */
plc_residual[i] = SPL_MUL_16_16_RSFT(tot_gain, (pitchfact * plc_residual[i] + (32767 - pitchfact) * randvec[i] + 16384) >> 15, 15);
/* Shifting down the result one step extra to ensure that no overflow
will occur */
energy += SPL_MUL_16_16_RSFT(plc_residual[i], plc_residual[i], (s->prevScale + 1));
}
/* less than 30 dB, use only noise */
if (energy < SPL_SHIFT_W32(s->block_samples * 900, -s->prevScale - 1)) {
energy = 0;
for (i = 0; i < s->block_samples; i++) {
plc_residual[i] = randvec[i];
}
}
/* use the old LPC */
memcpy(plc_lpc, (*s).prev_lpc, (LPC_FILTERORDER + 1) * 2);
/* Update state in case there are multiple frame losses */
s->prevLag = lag;
s->per_square = max_perSquare;
} else { /* no packet loss, copy input */
memcpy(plc_residual, decresidual, s->block_samples * 2);
memcpy(plc_lpc, lpc, (LPC_FILTERORDER + 1) * 2);
s->consPLICount = 0;
}
/* update state */
s->prevPLI = PLI;
memcpy(s->prev_lpc, plc_lpc, (LPC_FILTERORDER + 1) * 2);
memcpy(s->prevResidual, plc_residual, s->block_samples * 2);
return;
}
static int xcorr_coeff(int16_t *target, int16_t *regressor,
int16_t subl, int16_t searchLen,
int16_t offset, int16_t step)
{
int16_t maxlag;
int16_t pos;
int16_t max;
int16_t cross_corr_scale, energy_scale;
int16_t cross_corr_sg_mod, cross_corr_sg_mod_max;
int32_t cross_corr, energy;
int16_t cross_corr_mod, energy_mod, enery_mod_max;
int16_t *tp, *rp;
int16_t *rp_beg, *rp_end;
int16_t totscale, totscale_max;
int16_t scalediff;
int32_t new_crit, max_crit;
int shifts;
int k;
/* Initializations, to make sure that the first one is selected */
cross_corr_sg_mod_max = 0;
enery_mod_max = INT16_MAX;
totscale_max = -500;
maxlag = 0;
pos = 0;
/* Find scale value and start position */
if (step == 1) {
max = max_abs_value_w16(regressor, (int16_t) (subl + searchLen - 1));
rp_beg = regressor;
rp_end = &regressor[subl];
} else { /* step== -1 */
max = max_abs_value_w16(&regressor[-searchLen], (int16_t) (subl + searchLen - 1));
rp_beg = &regressor[-1];
rp_end = &regressor[subl - 1];
}
/* Introduce a scale factor on the energy in int32_t in
order to make sure that the calculation does not
overflow */
if (max > 5000) {
shifts = 2;
} else {
shifts = 0;
}
/* Calculate the first energy, then do a +/- to get the other energies */
energy = scale_dot_product(regressor, regressor, subl, shifts);
for (k = 0; k < searchLen; k++) {
tp = target;
rp = &regressor[pos];
cross_corr = scale_dot_product(tp, rp, subl, shifts);
if ((energy > 0) && (cross_corr > 0)) {
/* Put cross correlation and energy on 16 bit word */
cross_corr_scale = norm_w32(cross_corr) - 16;
cross_corr_mod = (int16_t) SPL_SHIFT_W32(cross_corr, cross_corr_scale);
energy_scale = norm_w32(energy) - 16;
energy_mod = (int16_t) SPL_SHIFT_W32(energy, energy_scale);
/* Square cross correlation and store upper int16_t */
cross_corr_sg_mod = (int16_t) SPL_MUL_16_16_RSFT(cross_corr_mod, cross_corr_mod, 16);
/* Calculate the total number of (dynamic) right shifts that have
been performed on (cross_corr*cross_corr)/energy
*/
totscale = energy_scale - (cross_corr_scale * 2);
/* Calculate the shift difference in order to be able to compare the two
(cross_corr*cross_corr)/energy in the same domain
*/
scalediff = totscale - totscale_max;
scalediff = FFMIN(scalediff, 31);
scalediff = FFMAX(scalediff, -31);
/* Compute the cross multiplication between the old best criteria
and the new one to be able to compare them without using a
division */
if (scalediff < 0) {
new_crit = ((int32_t) cross_corr_sg_mod * enery_mod_max) >> (-scalediff);
max_crit = ((int32_t) cross_corr_sg_mod_max * energy_mod);
} else {
new_crit = ((int32_t) cross_corr_sg_mod * enery_mod_max);
max_crit = ((int32_t) cross_corr_sg_mod_max * energy_mod) >> scalediff;
}
/* Store the new lag value if the new criteria is larger
than previous largest criteria */
if (new_crit > max_crit) {
cross_corr_sg_mod_max = cross_corr_sg_mod;
enery_mod_max = energy_mod;
totscale_max = totscale;
maxlag = k;
}
}
pos += step;
/* Do a +/- to get the next energy */
energy += (unsigned)step * ((*rp_end * *rp_end - *rp_beg * *rp_beg) >> shifts);
rp_beg += step;
rp_end += step;
}
return maxlag + offset;
}
static void hp_output(int16_t *signal, const int16_t *ba, int16_t *y,
int16_t *x, int16_t len)
{
int32_t tmp;
for (int i = 0; i < len; i++) {
tmp = SPL_MUL_16_16(y[1], ba[3]); /* (-a[1])*y[i-1] (low part) */
tmp += SPL_MUL_16_16(y[3], ba[4]); /* (-a[2])*y[i-2] (low part) */
tmp = (tmp >> 15);
tmp += SPL_MUL_16_16(y[0], ba[3]); /* (-a[1])*y[i-1] (high part) */
tmp += SPL_MUL_16_16(y[2], ba[4]); /* (-a[2])*y[i-2] (high part) */
tmp = (tmp * 2);
tmp += SPL_MUL_16_16(signal[i], ba[0]); /* b[0]*x[0] */
tmp += SPL_MUL_16_16(x[0], ba[1]); /* b[1]*x[i-1] */
tmp += SPL_MUL_16_16(x[1], ba[2]); /* b[2]*x[i-2] */
/* Update state (input part) */
x[1] = x[0];
x[0] = signal[i];
/* Convert back to Q0 and multiply with 2 */
signal[i] = av_clip_intp2(tmp + 1024, 26) >> 11;
/* Update state (filtered part) */
y[2] = y[0];
y[3] = y[1];
/* upshift tmp by 3 with saturation */
if (tmp > 268435455) {
tmp = INT32_MAX;
} else if (tmp < -268435456) {
tmp = INT32_MIN;
} else {
tmp = tmp * 8;
}
y[0] = tmp >> 16;
y[1] = (tmp - (y[0] * (1 << 16))) >> 1;
}
}
static int ilbc_decode_frame(AVCodecContext *avctx, void *data,
int *got_frame_ptr, AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
AVFrame *frame = data;
ILBCContext *s = avctx->priv_data;
int mode = s->mode, ret;
int16_t *plc_data = &s->plc_residual[LPC_FILTERORDER];
if ((ret = init_get_bits8(&s->gb, buf, avpkt->size)) < 0)
return ret;
memset(&s->frame, 0, sizeof(ILBCFrame));
frame->nb_samples = s->block_samples;
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
return ret;
if (unpack_frame(s))
mode = 0;
if (s->frame.start < 1 || s->frame.start > 5)
mode = 0;
if (mode) {
index_conv(s->frame.cb_index);
lsf_dequantization(s->lsfdeq, s->frame.lsf, s->lpc_n);
lsf_check_stability(s->lsfdeq, LPC_FILTERORDER, s->lpc_n);
lsp_interpolate(s->syntdenum, s->weightdenum,
s->lsfdeq, LPC_FILTERORDER, s);
decode_residual(s, &s->frame, s->decresidual, s->syntdenum);
do_plc(s->plc_residual, s->plc_lpc, 0,
s->decresidual, s->syntdenum + (LPC_FILTERORDER + 1) * (s->nsub - 1),
s->last_lag, s);
memcpy(s->decresidual, s->plc_residual, s->block_samples * 2);
}
if (s->enhancer) {
/* TODO */
} else {
int16_t lag, i;
/* Find last lag (since the enhancer is not called to give this info) */
if (s->mode == 20) {
lag = xcorr_coeff(&s->decresidual[s->block_samples-60], &s->decresidual[s->block_samples-80],
60, 80, 20, -1);
} else {
lag = xcorr_coeff(&s->decresidual[s->block_samples-ENH_BLOCKL],
&s->decresidual[s->block_samples-ENH_BLOCKL-20],
ENH_BLOCKL, 100, 20, -1);
}
/* Store lag (it is needed if next packet is lost) */
s->last_lag = lag;
/* copy data and run synthesis filter */
memcpy(plc_data, s->decresidual, s->block_samples * 2);
/* Set up the filter state */
memcpy(&plc_data[-LPC_FILTERORDER], s->syntMem, LPC_FILTERORDER * 2);
for (i = 0; i < s->nsub; i++) {
filter_arfq12(plc_data+i*SUBL, plc_data+i*SUBL,
s->syntdenum + i*(LPC_FILTERORDER + 1),
LPC_FILTERORDER + 1, SUBL);
}
/* Save the filter state */
memcpy(s->syntMem, &plc_data[s->block_samples-LPC_FILTERORDER], LPC_FILTERORDER * 2);
}
memcpy(frame->data[0], plc_data, s->block_samples * 2);
hp_output((int16_t *)frame->data[0], hp_out_coeffs,
s->hpimemy, s->hpimemx, s->block_samples);
memcpy(s->old_syntdenum, s->syntdenum, s->nsub*(LPC_FILTERORDER + 1) * 2);
s->prev_enh_pl = 0;
if (mode == 0)
s->prev_enh_pl = 1;
*got_frame_ptr = 1;
return avpkt->size;
}
static av_cold int ilbc_decode_init(AVCodecContext *avctx)
{
ILBCContext *s = avctx->priv_data;
if (avctx->block_align == 38)
s->mode = 20;
else if (avctx->block_align == 50)
s->mode = 30;
else if (avctx->bit_rate > 0)
s->mode = avctx->bit_rate <= 14000 ? 30 : 20;
else
return AVERROR_INVALIDDATA;
avctx->channels = 1;
avctx->channel_layout = AV_CH_LAYOUT_MONO;
avctx->sample_rate = 8000;
avctx->sample_fmt = AV_SAMPLE_FMT_S16;
if (s->mode == 30) {
s->block_samples = 240;
s->nsub = NSUB_30MS;
s->nasub = NASUB_30MS;
s->lpc_n = LPC_N_30MS;
s->state_short_len = STATE_SHORT_LEN_30MS;
} else {
s->block_samples = 160;
s->nsub = NSUB_20MS;
s->nasub = NASUB_20MS;
s->lpc_n = LPC_N_20MS;
s->state_short_len = STATE_SHORT_LEN_20MS;
}
return 0;
}
const AVCodec ff_ilbc_decoder = {
.name = "ilbc",
.long_name = NULL_IF_CONFIG_SMALL("iLBC (Internet Low Bitrate Codec)"),
.type = AVMEDIA_TYPE_AUDIO,
.id = AV_CODEC_ID_ILBC,
.init = ilbc_decode_init,
.decode = ilbc_decode_frame,
.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_CHANNEL_CONF,
.priv_data_size = sizeof(ILBCContext),
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
};
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