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rdft: reorder functions to avoid static prototype 

Originally committed as revision 22610 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Måns Rullgård 2010-03-20 21:27:06 +00:00
parent 2881c83127
commit 1366f05978
1 changed files with 28 additions and 30 deletions
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58
libavcodec/rdft.c
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@ -50,36 +50,6 @@ SINTABLE_CONST FFTSample * const ff_sin_tabs[] = {
ff_sin_2048, ff_sin_4096, ff_sin_8192, ff_sin_16384, ff_sin_32768, ff_sin_65536,
};
static void ff_rdft_calc_c(RDFTContext* s, FFTSample* data);
av_cold int ff_rdft_init(RDFTContext *s, int nbits, enum RDFTransformType trans)
{
int n = 1 << nbits;
int i;
const double theta = (trans == DFT_R2C || trans == DFT_C2R ? -1 : 1)*2*M_PI/n;
s->nbits = nbits;
s->inverse = trans == IDFT_C2R || trans == DFT_C2R;
s->sign_convention = trans == IDFT_R2C || trans == DFT_C2R ? 1 : -1;
if (nbits < 4 || nbits > 16)
return -1;
if (ff_fft_init(&s->fft, nbits-1, trans == IDFT_C2R || trans == IDFT_R2C) < 0)
return -1;
ff_init_ff_cos_tabs(nbits);
s->tcos = ff_cos_tabs[nbits];
s->tsin = ff_sin_tabs[nbits]+(trans == DFT_R2C || trans == DFT_C2R)*(n>>2);
#if !CONFIG_HARDCODED_TABLES
for (i = 0; i < (n>>2); i++) {
s->tsin[i] = sin(i*theta);
}
#endif
s->rdft_calc = ff_rdft_calc_c;
return 0;
}
/** Map one real FFT into two parallel real even and odd FFTs. Then interleave
* the two real FFTs into one complex FFT. Unmangle the results.
* ref: http://www.engineeringproductivitytools.com/stuff/T0001/PT10.HTM
@ -126,6 +96,34 @@ static void ff_rdft_calc_c(RDFTContext* s, FFTSample* data)
}
}
av_cold int ff_rdft_init(RDFTContext *s, int nbits, enum RDFTransformType trans)
{
int n = 1 << nbits;
int i;
const double theta = (trans == DFT_R2C || trans == DFT_C2R ? -1 : 1)*2*M_PI/n;
s->nbits = nbits;
s->inverse = trans == IDFT_C2R || trans == DFT_C2R;
s->sign_convention = trans == IDFT_R2C || trans == DFT_C2R ? 1 : -1;
if (nbits < 4 || nbits > 16)
return -1;
if (ff_fft_init(&s->fft, nbits-1, trans == IDFT_C2R || trans == IDFT_R2C) < 0)
return -1;
ff_init_ff_cos_tabs(nbits);
s->tcos = ff_cos_tabs[nbits];
s->tsin = ff_sin_tabs[nbits]+(trans == DFT_R2C || trans == DFT_C2R)*(n>>2);
#if !CONFIG_HARDCODED_TABLES
for (i = 0; i < (n>>2); i++) {
s->tsin[i] = sin(i*theta);
}
#endif
s->rdft_calc = ff_rdft_calc_c;
return 0;
}
av_cold void ff_rdft_end(RDFTContext *s)
{
ff_fft_end(&s->fft);