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Clean up FFT related comments.
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Originally committed as revision 16721 to svn://svn.ffmpeg.org/ffmpeg/trunk
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aconverse committed Jan 22, 2009
1 parent 082491c commit 8f05c99
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Showing 2 changed files with 12 additions and 12 deletions.
12 changes: 12 additions & 0 deletions libavcodec/dsputil.h
Expand Up @@ -674,6 +674,11 @@ typedef struct FFTContext {
void (*imdct_half)(struct MDCTContext *s, FFTSample *output, const FFTSample *input);
} FFTContext;

/**
* Sets up a complex FFT.
* @param nbits log2 of the length of the input array
* @param inverse if 0 perform the forward transform, if 1 perform the inverse
*/
int ff_fft_init(FFTContext *s, int nbits, int inverse);
void ff_fft_permute_c(FFTContext *s, FFTComplex *z);
void ff_fft_permute_sse(FFTContext *s, FFTComplex *z);
Expand All @@ -683,10 +688,17 @@ void ff_fft_calc_3dn(FFTContext *s, FFTComplex *z);
void ff_fft_calc_3dn2(FFTContext *s, FFTComplex *z);
void ff_fft_calc_altivec(FFTContext *s, FFTComplex *z);

/**
* Do the permutation needed BEFORE calling ff_fft_calc().
*/
static inline void ff_fft_permute(FFTContext *s, FFTComplex *z)
{
s->fft_permute(s, z);
}
/**
* Do a complex FFT with the parameters defined in ff_fft_init(). The
* input data must be permuted before. No 1.0/sqrt(n) normalization is done.
*/
static inline void ff_fft_calc(FFTContext *s, FFTComplex *z)
{
s->fft_calc(s, z);
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12 changes: 0 additions & 12 deletions libavcodec/fft.c
Expand Up @@ -58,10 +58,6 @@ static int split_radix_permutation(int i, int n, int inverse)
else return split_radix_permutation(i, m, inverse)*4 - 1;
}

/**
* The size of the FFT is 2^nbits. If inverse is TRUE, inverse FFT is
* done
*/
int ff_fft_init(FFTContext *s, int nbits, int inverse)
{
int i, j, m, n;
Expand Down Expand Up @@ -185,9 +181,6 @@ int ff_fft_init(FFTContext *s, int nbits, int inverse)
return -1;
}

/**
* Do the permutation needed BEFORE calling ff_fft_calc()
*/
void ff_fft_permute_c(FFTContext *s, FFTComplex *z)
{
int j, k, np;
Expand Down Expand Up @@ -374,11 +367,6 @@ static void (*fft_dispatch[])(FFTComplex*) = {
fft2048, fft4096, fft8192, fft16384, fft32768, fft65536,
};

/**
* Do a complex FFT with the parameters defined in ff_fft_init(). The
* input data must be permuted before with s->revtab table. No
* 1.0/sqrt(n) normalization is done.
*/
void ff_fft_calc_c(FFTContext *s, FFTComplex *z)
{
fft_dispatch[s->nbits-2](z);
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