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Increasing the pitch gain resolution

--- a/libcelt/celt.c

+++ b/libcelt/celt.c

@@ -1105,24 +1105,25 @@

       pf_threshold = MAX16(pf_threshold, QCONST16(.2f,15));

       if (gain1<pf_threshold)

       {

-         if(st->start==0 && tell+17<=total_bits)

+         if(st->start==0 && tell+16<=total_bits)

             ec_enc_bit_logp(enc, 0, 1);

          gain1 = 0;

          pf_on = 0;

       } else {

+         /*This block is not gated by a total bits check only because

+           of the nbAvailableBytes check above.*/

          int qg;

          int octave;

-         if (gain1 > QCONST16(.6f,15))

-            gain1 = QCONST16(.6f,15);

          if (ABS16(gain1-st->prefilter_gain)<QCONST16(.1f,15))

             gain1=st->prefilter_gain;

 #ifdef FIXED_POINT

-         qg = ((gain1+2048)>>12)-2;

+         qg = ((gain1+1536)>>10)/3-1;

 #else

-         qg = floor(.5+gain1*8)-2;

+         qg = floor(.5+gain1*32/3)-1;

 #endif

+         qg = IMAX(0, IMIN(7, qg));

          ec_enc_bit_logp(enc, 1, 1);

          pitch_index += 1;

          octave = EC_ILOG(pitch_index)-5;

@@ -1129,14 +1130,17 @@

          ec_enc_uint(enc, octave, 6);

          ec_enc_bits(enc, pitch_index-(16<<octave), 4+octave);

          pitch_index -= 1;

-         ec_enc_bits(enc, qg, 2);

-         gain1 = QCONST16(.125f,15)*(qg+2);

-         ec_enc_icdf(enc, prefilter_tapset, tapset_icdf, 2);

+         ec_enc_bits(enc, qg, 3);

+         if (ec_enc_tell(enc, 0)+2<=total_bits)

+            ec_enc_icdf(enc, prefilter_tapset, tapset_icdf, 2);

+         else

+           prefilter_tapset = 0;

+         gain1 = QCONST16(0.09375f,15)*(qg+1);

          pf_on = 1;

       }

       /*printf("%d %f\n", pitch_index, gain1);*/

 #else /* ENABLE_POSTFILTER */

-      if(st->start==0 && tell+17<=total_bits)

+      if(st->start==0 && tell+16<=total_bits)

          ec_enc_bit_logp(enc, 0, 1);

       pf_on = 0;

 #endif /* ENABLE_POSTFILTER */

@@ -2258,7 +2262,7 @@

    postfilter_gain = 0;

    postfilter_pitch = 0;

    postfilter_tapset = 0;

-   if (st->start==0 && tell+17 <= total_bits)

+   if (st->start==0 && tell+16 <= total_bits)

    {

       if(ec_dec_bit_logp(dec, 1))

       {

@@ -2266,9 +2270,10 @@

          int qg, octave;

          octave = ec_dec_uint(dec, 6);

          postfilter_pitch = (16<<octave)+ec_dec_bits(dec, 4+octave)-1;

-         qg = ec_dec_bits(dec, 2);

-         postfilter_tapset = ec_dec_icdf(dec, tapset_icdf, 2);

-         postfilter_gain = QCONST16(.125f,15)*(qg+2);

+         qg = ec_dec_bits(dec, 3);

+         if (ec_dec_tell(dec, 0)+2<=total_bits)

+            postfilter_tapset = ec_dec_icdf(dec, tapset_icdf, 2);

+         postfilter_gain = QCONST16(.09375f,15)*(qg+1);

 #else /* ENABLE_POSTFILTER */

          RESTORE_STACK;

          return CELT_CORRUPTED_DATA;