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Add ff_init_ff_cos_tabs function and use it in rdft.c to ensure that the

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necessary ff_cos_tabs tables are initialized.
Fixes issue 1507 (QDM2 broken since r20237 without hardcoded tables).

Originally committed as revision 20464 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Reimar Döffinger
2009-11-05 18:29:06 +00:00
parent 9cad7e2193
commit 1ffc6e8327
3 changed files with 22 additions and 9 deletions
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24
libavcodec/fft.c
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@@ -61,6 +61,20 @@ static int split_radix_permutation(int i, int n, int inverse)
else return split_radix_permutation(i, m, inverse)*4 - 1;
}
av_cold void ff_init_ff_cos_tabs(int index)
{
#if !CONFIG_HARDCODED_TABLES
int i;
int m = 1<<index;
double freq = 2*M_PI/m;
FFTSample *tab = ff_cos_tabs[index];
for(i=0; i<=m/4; i++)
tab[i] = cos(i*freq);
for(i=1; i<m/4; i++)
tab[m/2-i] = tab[i];
#endif
}
av_cold int ff_fft_init(FFTContext *s, int nbits, int inverse)
{
int i, j, m, n;
@@ -96,17 +110,9 @@ av_cold int ff_fft_init(FFTContext *s, int nbits, int inverse)
if (HAVE_MMX) ff_fft_init_mmx(s);
if (s->split_radix) {
#if !CONFIG_HARDCODED_TABLES
for(j=4; j<=nbits; j++) {
int m = 1<<j;
double freq = 2*M_PI/m;
FFTSample *tab = ff_cos_tabs[j];
for(i=0; i<=m/4; i++)
tab[i] = cos(i*freq);
for(i=1; i<m/4; i++)
tab[m/2-i] = tab[i];
ff_init_ff_cos_tabs(j);
}
#endif
for(i=0; i<n; i++)
s->revtab[-split_radix_permutation(i, n, s->inverse) & (n-1)] = i;
s->tmp_buf = av_malloc(n * sizeof(FFTComplex));