X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Facelp_pitch_delay.c;h=66d65a6903c28a1e87d15735406460ed1e0e04c3;hb=6718536ba500d8a471bae3849f124da892936c70;hp=c2155a5c0c7d63d999de276225f2b18bd7ea0e7b;hpb=9a9ceb8776264c799ff9669ed7e287a5daaab564;p=ffmpeg

diff --git a/libavcodec/acelp_pitch_delay.c b/libavcodec/acelp_pitch_delay.c
index c2155a5c0c7..66d65a6903c 100644
--- a/libavcodec/acelp_pitch_delay.c
+++ b/libavcodec/acelp_pitch_delay.c
@@ -105,9 +105,20 @@ 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));
     return mr_energy >> 12;
+#endif
 }
 
 float ff_amr_set_fixed_gain(float fixed_gain_factor, float fixed_mean_energy,