*
* 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
*/
+#include "libavutil/common.h"
+#include "libavutil/float_dsp.h"
+#include "libavutil/mathematics.h"
#include "avcodec.h"
-#include "dsputil.h"
#include "acelp_pitch_delay.h"
#include "celp_math.h"
if(erasure)
quant_energy[0] = FFMAX(avg_gain >> log2_ma_pred_order, -10240) - 4096; // -10 and -4 in (5.10)
else
- quant_energy[0] = (6165 * ((ff_log2(gain_corr_factor) >> 2) - (13 << 13))) >> 13;
+ quant_energy[0] = (6165 * ((ff_log2_q15(gain_corr_factor) >> 2) - (13 << 13))) >> 13;
}
int16_t ff_acelp_decode_gain_code(
for(i=0; i<ma_pred_order; i++)
mr_energy += quant_energy[i] * ma_prediction_coeff[i];
-#ifdef G729_BITEXACT
- mr_energy += (((-6165LL * ff_log2(dsp->scalarproduct_int16(fc_v, fc_v, subframe_size, 0))) >> 3) & ~0x3ff);
-
- mr_energy = (5439 * (mr_energy >> 15)) >> 8; // (0.15) = (0.15) * (7.23)
-
- return bidir_sal(
- ((ff_exp2(mr_energy & 0x7fff) + 16) >> 5) * (gain_corr_factor >> 1),
- (mr_energy >> 15) - 25
- );
-#else
mr_energy = gain_corr_factor * exp(M_LN10 / (20 << 23) * mr_energy) /
- sqrt(dsp->scalarproduct_int16(fc_v, fc_v, subframe_size, 0));
+ sqrt(dsp->scalarproduct_int16(fc_v, fc_v, subframe_size));
return mr_energy >> 12;
-#endif
+}
+
+float ff_amr_set_fixed_gain(float fixed_gain_factor, float fixed_mean_energy,
+ float *prediction_error, float energy_mean,
+ const float *pred_table)
+{
+ // Equations 66-69:
+ // ^g_c = ^gamma_gc * 100.05 (predicted dB + mean dB - dB of fixed vector)
+ // Note 10^(0.05 * -10log(average x2)) = 1/sqrt((average x2)).
+ float val = fixed_gain_factor *
+ exp2f(M_LOG2_10 * 0.05 *
+ (avpriv_scalarproduct_float_c(pred_table, prediction_error, 4) +
+ energy_mean)) /
+ sqrtf(fixed_mean_energy);
+
+ // update quantified prediction error energy history
+ memmove(&prediction_error[0], &prediction_error[1],
+ 3 * sizeof(prediction_error[0]));
+ prediction_error[3] = 20.0 * log10f(fixed_gain_factor);
+
+ return val;
+}
+
+void ff_decode_pitch_lag(int *lag_int, int *lag_frac, int pitch_index,
+ const int prev_lag_int, const int subframe,
+ int third_as_first, int resolution)
+{
+ /* Note n * 10923 >> 15 is floor(x/3) for 0 <= n <= 32767 */
+ if (subframe == 0 || (subframe == 2 && third_as_first)) {
+
+ if (pitch_index < 197)
+ pitch_index += 59;
+ else
+ pitch_index = 3 * pitch_index - 335;
+
+ } else {
+ if (resolution == 4) {
+ int search_range_min = av_clip(prev_lag_int - 5, PITCH_DELAY_MIN,
+ PITCH_DELAY_MAX - 9);
+
+ // decoding with 4-bit resolution
+ if (pitch_index < 4) {
+ // integer only precision for [search_range_min, search_range_min+3]
+ pitch_index = 3 * (pitch_index + search_range_min) + 1;
+ } else if (pitch_index < 12) {
+ // 1/3 fractional precision for [search_range_min+3 1/3, search_range_min+5 2/3]
+ pitch_index += 3 * search_range_min + 7;
+ } else {
+ // integer only precision for [search_range_min+6, search_range_min+9]
+ pitch_index = 3 * (pitch_index + search_range_min - 6) + 1;
+ }
+ } else {
+ // decoding with 5 or 6 bit resolution, 1/3 fractional precision
+ pitch_index--;
+
+ if (resolution == 5) {
+ pitch_index += 3 * av_clip(prev_lag_int - 10, PITCH_DELAY_MIN,
+ PITCH_DELAY_MAX - 19);
+ } else
+ pitch_index += 3 * av_clip(prev_lag_int - 5, PITCH_DELAY_MIN,
+ PITCH_DELAY_MAX - 9);
+ }
+ }
+ *lag_int = pitch_index * 10923 >> 15;
+ *lag_frac = pitch_index - 3 * *lag_int - 1;
}