dct: bypass table allocation for DCT_II of size 32

The size-32 DCT_II has a special implementation which doesn't use
the normal tables.  Skipping allocation of these in this case saves
some memory.

Signed-off-by: Mans Rullgard <mans@mansr.com>
This commit is contained in:
Mans Rullgard 2011-05-16 15:57:04 +01:00
parent 257de5fb25
commit 721d6f2dc5
1 changed files with 6 additions and 3 deletions

View File

@ -180,9 +180,14 @@ av_cold int ff_dct_init(DCTContext *s, int nbits, enum DCTTransformType inverse)
int n = 1 << nbits;
int i;
memset(s, 0, sizeof(*s));
s->nbits = nbits;
s->inverse = inverse;
if (inverse == DCT_II && nbits == 5) {
s->dct_calc = dct32_func;
} else {
ff_init_ff_cos_tabs(nbits+2);
s->costab = ff_cos_tabs[nbits+2];
@ -203,9 +208,7 @@ av_cold int ff_dct_init(DCTContext *s, int nbits, enum DCTTransformType inverse)
case DCT_III: s->dct_calc = ff_dct_calc_III_c; break;
case DST_I : s->dct_calc = ff_dst_calc_I_c; break;
}
if (inverse == DCT_II && nbits == 5)
s->dct_calc = dct32_func;
}
s->dct32 = dct32;
if (HAVE_MMX) ff_dct_init_mmx(s);