Rename pred() to eval_lpc_coeffs() and add a doxy comment

Originally committed as revision 14361 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Vitor Sessak 2008-07-24 04:05:41 +00:00
parent a0cce1587b
commit a3896c6377
1 changed files with 9 additions and 3 deletions

View File

@ -97,7 +97,13 @@ static void colmult(float *tgt, const float *m1, const float *m2, int n)
*(tgt++) = (*(m1++)) * (*(m2++));
}
static int pred(const float *in, float *tgt, int n)
/**
* Converts autocorrelation coefficients to LPC coefficients using the
* Levinson-Durbin algorithm. See blocks 37 and 50 of the G.728 specification.
*
* @return 1 if success, 0 if fail
*/
static int eval_lpc_coeffs(const float *in, float *tgt, int n)
{
int x, y;
double f0, f1, f2;
@ -189,7 +195,7 @@ static void update(Real288_internal *glob)
do_hybrid_window(36, 40, 35, buffer1, temp1, glob->st1a, glob->st1b,
syn_window);
if (pred(temp1, glob->st1, 36))
if (eval_lpc_coeffs(temp1, glob->st1, 36))
colmult(glob->pr1, glob->st1, table1a, 36);
memcpy(buffer2 , glob->history + 4, 4*sizeof(*buffer2));
@ -198,7 +204,7 @@ static void update(Real288_internal *glob)
do_hybrid_window(10, 8, 20, buffer2, temp2, glob->st2a, glob->st2b,
gain_window);
if (pred(temp2, glob->st2, 10))
if (eval_lpc_coeffs(temp2, glob->st2, 10))
colmult(glob->pr2, glob->st2, table2a, 10);
}