示例#1
0
int main(void)
{
   int i;
   int ret = 0;
   ec_enc enc;
   ec_dec dec;
   ec_byte_buffer buf;
   unsigned char *ptr;
   int val[10000], decay[10000];
   ALLOC_STACK;
   ptr = malloc(DATA_SIZE);
   ec_byte_writeinit_buffer(&buf, ptr, DATA_SIZE);
   //ec_byte_writeinit(&buf);
   ec_enc_init(&enc,&buf);
   
   val[0] = 3; decay[0] = 6000;
   val[1] = 0; decay[1] = 5800;
   val[2] = -1; decay[2] = 5600;
   for (i=3;i<10000;i++)
   {
      val[i] = rand()%15-7;
      decay[i] = rand()%11000+5000;
   }
   for (i=0;i<10000;i++)
      ec_laplace_encode(&enc, &val[i], decay[i]);      
      
   ec_enc_done(&enc);

   ec_byte_readinit(&buf,ec_byte_get_buffer(&buf),ec_byte_bytes(&buf));
   ec_dec_init(&dec,&buf);

   for (i=0;i<10000;i++)
   {
      int d = ec_laplace_decode(&dec, decay[i]);
      if (d != val[i])
      {
         fprintf (stderr, "Got %d instead of %d\n", d, val[i]);
         ret = 1;
      }
   }
   
   return ret;
}
示例#2
0
static int quant_coarse_energy_impl(const CELTMode *m, int start, int end,
      const opus_val16 *eBands, opus_val16 *oldEBands,
      opus_int32 budget, opus_int32 tell,
      const unsigned char *prob_model, opus_val16 *error, ec_enc *enc,
      int C, int LM, int intra, opus_val16 max_decay)
{
   int i, c;
   int badness = 0;
   opus_val32 prev[2] = {0,0};
   opus_val16 coef;
   opus_val16 beta;

   if (tell+3 <= budget)
      ec_enc_bit_logp(enc, intra, 3);
   if (intra)
   {
      coef = 0;
      beta = beta_intra;
   } else {
      beta = beta_coef[LM];
      coef = pred_coef[LM];
   }

   /* Encode at a fixed coarse resolution */
   for (i=start;i<end;i++)
   {
      c=0;
      do {
         int bits_left;
         int qi, qi0;
         opus_val32 q;
         opus_val16 x;
         opus_val32 f, tmp;
         opus_val16 oldE;
         opus_val16 decay_bound;
         x = eBands[i+c*m->nbEBands];
         oldE = MAX16(-QCONST16(9.f,DB_SHIFT), oldEBands[i+c*m->nbEBands]);
#ifdef FIXED_POINT
         f = SHL32(EXTEND32(x),7) - PSHR32(MULT16_16(coef,oldE), 8) - prev[c];
         /* Rounding to nearest integer here is really important! */
         qi = (f+QCONST32(.5f,DB_SHIFT+7))>>(DB_SHIFT+7);
         decay_bound = EXTRACT16(MAX32(-QCONST16(28.f,DB_SHIFT),
               SUB32((opus_val32)oldEBands[i+c*m->nbEBands],max_decay)));
#else
         f = x-coef*oldE-prev[c];
         /* Rounding to nearest integer here is really important! */
         qi = (int)floor(.5f+f);
         decay_bound = MAX16(-QCONST16(28.f,DB_SHIFT), oldEBands[i+c*m->nbEBands]) - max_decay;
#endif
         /* Prevent the energy from going down too quickly (e.g. for bands
            that have just one bin) */
         if (qi < 0 && x < decay_bound)
         {
            qi += (int)SHR16(SUB16(decay_bound,x), DB_SHIFT);
            if (qi > 0)
               qi = 0;
         }
         qi0 = qi;
         /* If we don't have enough bits to encode all the energy, just assume
             something safe. */
         tell = ec_tell(enc);
         bits_left = budget-tell-3*C*(end-i);
         if (i!=start && bits_left < 30)
         {
            if (bits_left < 24)
               qi = IMIN(1, qi);
            if (bits_left < 16)
               qi = IMAX(-1, qi);
         }
         if (budget-tell >= 15)
         {
            int pi;
            pi = 2*IMIN(i,20);
            ec_laplace_encode(enc, &qi,
                  prob_model[pi]<<7, prob_model[pi+1]<<6);
         }
         else if(budget-tell >= 2)
         {
            qi = IMAX(-1, IMIN(qi, 1));
            ec_enc_icdf(enc, 2*qi^-(qi<0), small_energy_icdf, 2);
         }
         else if(budget-tell >= 1)
         {
            qi = IMIN(0, qi);
            ec_enc_bit_logp(enc, -qi, 1);
         }
         else
            qi = -1;
         error[i+c*m->nbEBands] = PSHR32(f,7) - SHL16(qi,DB_SHIFT);
         badness += abs(qi0-qi);
         q = (opus_val32)SHL32(EXTEND32(qi),DB_SHIFT);

         tmp = PSHR32(MULT16_16(coef,oldE),8) + prev[c] + SHL32(q,7);
#ifdef FIXED_POINT
         tmp = MAX32(-QCONST32(28.f, DB_SHIFT+7), tmp);
#endif
         oldEBands[i+c*m->nbEBands] = PSHR32(tmp, 7);
         prev[c] = prev[c] + SHL32(q,7) - MULT16_16(beta,PSHR32(q,8));
      } while (++c < C);
   }
   return badness;
}