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Functions | Variables
rdft.c File Reference

(Inverse) Real Discrete Fourier Transforms. More...

#include <stdlib.h>
#include <math.h>
#include "libavutil/mathematics.h"
#include "rdft.h"

Go to the source code of this file.


 SINTABLE (1024)
 SINTABLE (2048)
 SINTABLE (4096)
 SINTABLE (8192)
 SINTABLE (16384)
 SINTABLE (32768)
 SINTABLE (65536)
static void rdft_calc_c (RDFTContext *s, FFTSample *data)
 Map one real FFT into two parallel real even and odd FFTs. More...
av_cold int ff_rdft_init (RDFTContext *s, int nbits, enum RDFTransformType trans)
 Set up a real FFT. More...
av_cold void ff_rdft_end (RDFTContext *s)


FFTSample *const 
ff_sin_tabs []

Detailed Description

(Inverse) Real Discrete Fourier Transforms.

Definition in file rdft.c.

Function Documentation

SINTABLE ( 16  )
SINTABLE ( 32  )
SINTABLE ( 64  )
SINTABLE ( 128  )
SINTABLE ( 256  )
SINTABLE ( 512  )
SINTABLE ( 1024  )
SINTABLE ( 2048  )
SINTABLE ( 4096  )
SINTABLE ( 8192  )
SINTABLE ( 16384  )
SINTABLE ( 32768  )
SINTABLE ( 65536  )
static void rdft_calc_c ( RDFTContext s,
FFTSample data 

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

Definition at line 57 of file rdft.c.

Referenced by ff_rdft_init().

av_cold int ff_rdft_init ( RDFTContext s,
int  nbits,
enum RDFTransformType  trans 

Set up a real FFT.

nbitslog2 of the length of the input array
transthe type of transform

Definition at line 99 of file rdft.c.

Referenced by decode_init(), ff_dct_init(), main(), qdm2_decode_init(), and wmavoice_decode_init().

av_cold void ff_rdft_end ( RDFTContext s)

Definition at line 132 of file rdft.c.

Referenced by decode_end(), ff_dct_end(), main(), qdm2_decode_close(), and wmavoice_decode_end().

Variable Documentation

SINTABLE_CONST FFTSample* const ff_sin_tabs[]
Initial value:
= {
ff_sin_16, ff_sin_32, ff_sin_64, ff_sin_128, ff_sin_256, ff_sin_512, ff_sin_1024,
ff_sin_2048, ff_sin_4096, ff_sin_8192, ff_sin_16384, ff_sin_32768, ff_sin_65536,
#define NULL
Definition: coverity.c:32

Definition at line 47 of file rdft.c.

Referenced by ff_rdft_init().