ref: 5bdb7dbafc1b07d0dcea2715f84b8096f4a95112
parent: 37546cc3f60fd52880663d26f3e1cc0915f19538
author: Timothy B. Terriberry <[email protected]>
date: Tue Jul 27 09:33:55 EDT 2010
Eliminate the loop when encoding the split angle. Use a closed-form formula for the codebook parameters instead.
--- a/libcelt/bands.c
+++ b/libcelt/bands.c
@@ -655,20 +655,12 @@
ft = ((1<<qb>>1)+1)*((1<<qb>>1)+1);
if (encode)
{- int j;
- int fl=0;
- j=0;
- while(1)
- {- if (j==itheta)
- break;
- fl+=fs;
- if (j<(1<<qb>>1))
- fs++;
- else
- fs--;
- j++;
- }
+ int fl;
+
+ fs = itheta <= (1<<qb>>1) ? itheta + 1 : (1<<qb) + 1 - itheta;
+ fl = itheta <= (1<<qb>>1) ? itheta*(itheta + 1)>>1 :
+ ft - (((1<<qb) + 1 - itheta)*((1<<qb) + 2 - itheta)>>1);
+
ec_encode((ec_enc*)ec, fl, fl+fs, ft);
} else {int fl=0;