/*
* LSP routines for ACELP-based codecs
*
+ * Copyright (c) 2007 Reynaldo H. Verdejo Pinochet (QCELP decoder)
* Copyright (c) 2008 Vladimir Voroshilov
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
- * FFmpeg is distributed in the hope that it will be useful,
+ * Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
lsfq[lp_order-1] = FFMIN(lsfq[lp_order-1], lsfq_max);//Is warning required ?
}
+void ff_set_min_dist_lsf(float *lsf, double min_spacing, int size)
+{
+ int i;
+ float prev = 0.0;
+ for (i = 0; i < size; i++)
+ prev = lsf[i] = FFMAX(lsf[i], prev + min_spacing);
+}
+
void ff_acelp_lsf2lsp(int16_t *lsp, const int16_t *lsf, int lp_order)
{
int i;
lsp[i] = ff_cos(lsf[i] * 20861 >> 15); // divide by PI and (0,13) -> (0,14)
}
+void ff_acelp_lsf2lspd(double *lsp, const float *lsf, int lp_order)
+{
+ int i;
+
+ for(i = 0; i < lp_order; i++)
+ lsp[i] = cos(2.0 * M_PI * lsf[i]);
+}
+
/**
- * \brief decodes polynomial coefficients from LSP
- * \param f [out] decoded polynomial coefficients (-0x20000000 <= (3.22) <= 0x1fffffff)
- * \param lsp LSP coefficients (-0x8000 <= (0.15) <= 0x7fff)
+ * @brief decodes polynomial coefficients from LSP
+ * @param f [out] decoded polynomial coefficients (-0x20000000 <= (3.22) <= 0x1fffffff)
+ * @param lsp LSP coefficients (-0x8000 <= (0.15) <= 0x7fff)
*/
static void lsp2poly(int* f, const int16_t* lsp, int lp_half_order)
{
void ff_acelp_lsp2lpc(int16_t* lp, const int16_t* lsp, int lp_half_order)
{
int i;
- int f1[lp_half_order+1]; // (3.22)
- int f2[lp_half_order+1]; // (3.22)
+ int f1[MAX_LP_HALF_ORDER+1]; // (3.22)
+ int f2[MAX_LP_HALF_ORDER+1]; // (3.22)
lsp2poly(f1, lsp , lp_half_order);
lsp2poly(f2, lsp+1, lp_half_order);
}
}
+void ff_amrwb_lsp2lpc(const double *lsp, float *lp, int lp_order)
+{
+ int lp_half_order = lp_order >> 1;
+ double buf[MAX_LP_HALF_ORDER + 1];
+ double pa[MAX_LP_HALF_ORDER + 1];
+ double *qa = buf + 1;
+ int i,j;
+
+ qa[-1] = 0.0;
+
+ ff_lsp2polyf(lsp , pa, lp_half_order );
+ ff_lsp2polyf(lsp + 1, qa, lp_half_order - 1);
+
+ for (i = 1, j = lp_order - 1; i < lp_half_order; i++, j--) {
+ double paf = pa[i] * (1 + lsp[lp_order - 1]);
+ double qaf = (qa[i] - qa[i-2]) * (1 - lsp[lp_order - 1]);
+ lp[i-1] = (paf + qaf) * 0.5;
+ lp[j-1] = (paf - qaf) * 0.5;
+ }
+
+ lp[lp_half_order - 1] = (1.0 + lsp[lp_order - 1]) *
+ pa[lp_half_order] * 0.5;
+
+ lp[lp_order - 1] = lsp[lp_order - 1];
+}
+
void ff_acelp_lp_decode(int16_t* lp_1st, int16_t* lp_2nd, const int16_t* lsp_2nd, const int16_t* lsp_prev, int lp_order)
{
- int16_t lsp_1st[lp_order]; // (0.15)
+ int16_t lsp_1st[MAX_LP_ORDER]; // (0.15)
int i;
/* LSP values for first subframe (3.2.5 of G.729, Equation 24)*/
for(i=0; i<lp_order; i++)
-#ifdef G729_BITEXACT
- lsp_1st[i] = (lsp_2nd[i] >> 1) + (lsp_prev[i] >> 1);
-#else
lsp_1st[i] = (lsp_2nd[i] + lsp_prev[i]) >> 1;
-#endif
ff_acelp_lsp2lpc(lp_1st, lsp_1st, lp_order >> 1);
/* LSP values for second subframe (3.2.5 of G.729)*/
ff_acelp_lsp2lpc(lp_2nd, lsp_2nd, lp_order >> 1);
}
+
+void ff_lsp2polyf(const double *lsp, double *f, int lp_half_order)
+{
+ int i, j;
+
+ f[0] = 1.0;
+ f[1] = -2 * lsp[0];
+ lsp -= 2;
+ for(i=2; i<=lp_half_order; i++)
+ {
+ double val = -2 * lsp[2*i];
+ f[i] = val * f[i-1] + 2*f[i-2];
+ for(j=i-1; j>1; j--)
+ f[j] += f[j-1] * val + f[j-2];
+ f[1] += val;
+ }
+}
+
+void ff_acelp_lspd2lpc(const double *lsp, float *lpc, int lp_half_order)
+{
+ double pa[MAX_LP_HALF_ORDER+1], qa[MAX_LP_HALF_ORDER+1];
+ float *lpc2 = lpc + (lp_half_order << 1) - 1;
+
+ assert(lp_half_order <= MAX_LP_HALF_ORDER);
+
+ ff_lsp2polyf(lsp, pa, lp_half_order);
+ ff_lsp2polyf(lsp + 1, qa, lp_half_order);
+
+ while (lp_half_order--) {
+ double paf = pa[lp_half_order+1] + pa[lp_half_order];
+ double qaf = qa[lp_half_order+1] - qa[lp_half_order];
+
+ lpc [ lp_half_order] = 0.5*(paf+qaf);
+ lpc2[-lp_half_order] = 0.5*(paf-qaf);
+ }
+}
+
+void ff_sort_nearly_sorted_floats(float *vals, int len)
+{
+ int i,j;
+
+ for (i = 0; i < len - 1; i++)
+ for (j = i; j >= 0 && vals[j] > vals[j+1]; j--)
+ FFSWAP(float, vals[j], vals[j+1]);
+}