* 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
*/
#define FRAC_BITS 14
#include "mathops.h"
#include "lsp.h"
-#include "celp_math.h"
void ff_acelp_reorder_lsf(int16_t* lsfq, int lsfq_min_distance, int lsfq_min, int lsfq_max, int lp_order)
{
int i, j;
- /* sort lsfq in ascending order. float bubble agorithm,
+ /* sort lsfq in ascending order. float bubble algorithm,
O(n) if data already sorted, O(n^2) - otherwise */
for(i=0; i<lp_order-1; i++)
for(j=i; j>=0 && lsfq[j] > lsfq[j+1]; j--)
prev = lsf[i] = FFMAX(lsf[i], prev + min_spacing);
}
+
+/* Cosine table: base_cos[i] = (1 << 15) * cos(i * PI / 64) */
+static const int16_t tab_cos[65] =
+{
+ 32767, 32738, 32617, 32421, 32145, 31793, 31364, 30860,
+ 30280, 29629, 28905, 28113, 27252, 26326, 25336, 24285,
+ 23176, 22011, 20793, 19525, 18210, 16851, 15451, 14014,
+ 12543, 11043, 9515, 7965, 6395, 4810, 3214, 1609,
+ 1, -1607, -3211, -4808, -6393, -7962, -9513, -11040,
+ -12541, -14012, -15449, -16848, -18207, -19523, -20791, -22009,
+ -23174, -24283, -25334, -26324, -27250, -28111, -28904, -29627,
+ -30279, -30858, -31363, -31792, -32144, -32419, -32616, -32736, -32768,
+};
+
+static int16_t ff_cos(uint16_t arg)
+{
+ uint8_t offset= arg;
+ uint8_t ind = arg >> 8;
+
+ assert(arg <= 0x3fff);
+
+ return tab_cos[ind] + (offset * (tab_cos[ind+1] - tab_cos[ind]) >> 8);
+}
+
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[out] f 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);
ff_acelp_lsp2lpc(lp_2nd, lsp_2nd, lp_order >> 1);
}
-/**
- * Computes the Pa / (1 + z(-1)) or Qa / (1 - z(-1)) coefficients
- * needed for LSP to LPC conversion.
- * We only need to calculate the 6 first elements of the polynomial.
- *
- * @param lsp line spectral pairs in cosine domain
- * @param f [out] polynomial input/output as a vector
- *
- * TIA/EIA/IS-733 2.4.3.3.5-1/2
- */
-static void lsp2polyf(const double *lsp, double *f, int lp_half_order)
+void ff_lsp2polyf(const double *lsp, double *f, int lp_half_order)
{
int i, j;
assert(lp_half_order <= MAX_LP_HALF_ORDER);
- lsp2polyf(lsp, pa, lp_half_order);
- lsp2polyf(lsp + 1, qa, 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];