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Use hardcoded instead of runtime-calculated ff_cos_* tables if

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--enable-hardcoded-tables was used.
Due to the size, the code for the tables is generated at compile time.

Originally committed as revision 20232 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Reimar Döffinger
2009-10-14 21:41:24 +00:00
parent 6d924b5a5f
commit 16aec74761
4 changed files with 90 additions and 14 deletions
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39
libavcodec/fft.c
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@@ -28,20 +28,31 @@
#include "dsputil.h"
#if CONFIG_HARDCODED_TABLES
#define COSTABLE(size) \
extern const DECLARE_ALIGNED_16(FFTSample, ff_cos_##size[size/2]);
#else
#define COSTABLE(size) \
DECLARE_ALIGNED_16(FFTSample, ff_cos_##size[size/2]);
#endif
/* cos(2*pi*x/n) for 0<=x<=n/4, followed by its reverse */
DECLARE_ALIGNED_16(FFTSample, ff_cos_16[8]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_32[16]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_64[32]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_128[64]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_256[128]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_512[256]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_1024[512]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_2048[1024]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_4096[2048]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_8192[4096]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_16384[8192]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_32768[16384]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_65536[32768]);
COSTABLE(16)
COSTABLE(32)
COSTABLE(64)
COSTABLE(128)
COSTABLE(256)
COSTABLE(512)
COSTABLE(1024)
COSTABLE(2048)
COSTABLE(4096)
COSTABLE(8192)
COSTABLE(16384)
COSTABLE(32768)
COSTABLE(65536)
#if CONFIG_HARDCODED_TABLES
const
#endif
FFTSample * const ff_cos_tabs[] = {
ff_cos_16, ff_cos_32, ff_cos_64, ff_cos_128, ff_cos_256, ff_cos_512, ff_cos_1024,
ff_cos_2048, ff_cos_4096, ff_cos_8192, ff_cos_16384, ff_cos_32768, ff_cos_65536,
@@ -93,6 +104,7 @@ 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;
@@ -102,6 +114,7 @@ av_cold int ff_fft_init(FFTContext *s, int nbits, int inverse)
for(i=1; i<m/4; i++)
tab[m/2-i] = tab[i];
}
#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));