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Adapting the allocation trim based on the spectral tilt

--- a/libcelt/celt.c

+++ b/libcelt/celt.c

@@ -619,6 +619,8 @@

       const celt_word16 *bandLogE, int nbEBands, int LM, int C, int N0)

 {

    int i;

+   celt_word32 diff=0;

+   int c;

    int trim_index = 5;

    if (C==2)

    {

@@ -643,28 +645,29 @@

       else if (sum > QCONST16(.8f,10))

          trim_index-=1;

    }

-#if 0

-   float diff=0;

-   int c;

+

+   /* Estimate spectral tilt */

    c=0; do {

       for (i=0;i<nbEBands-1;i++)

       {

-         diff += bandLogE[i+c*nbEBands]*(i-.5*nbEBands);

+         diff += bandLogE[i+c*nbEBands]*(celt_int32)(2+2*i-nbEBands);

       }

    } while (++c<0);

    diff /= C*(nbEBands-1);

    /*printf("%f\n", diff);*/

-   if (diff > 4)

+   if (diff > QCONST16(2.f, DB_SHIFT))

       trim_index--;

-   if (diff > 8)

+   if (diff > QCONST16(8.f, DB_SHIFT))

       trim_index--;

-   if (diff < -4)

+   if (diff < -QCONST16(4.f, DB_SHIFT))

       trim_index++;

-#endif

+   if (diff < -QCONST16(10.f, DB_SHIFT))

+      trim_index++;

+

    if (trim_index<0)

       trim_index = 0;

-   if (trim_index>5)

-      trim_index = 5;

+   if (trim_index>10)

+      trim_index = 10;

    return trim_index;

 }