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Diffstat (limited to 'lib/mdct.h')
-rw-r--r-- | lib/mdct.h | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/lib/mdct.h b/lib/mdct.h new file mode 100644 index 0000000..3b8c9ba --- /dev/null +++ b/lib/mdct.h @@ -0,0 +1,70 @@ +/******************************************************************** + * * + * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE. * + * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS * + * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE * + * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. * + * * + * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2009 * + * by the Xiph.Org Foundation http://www.xiph.org/ * + * * + ******************************************************************** + + function: modified discrete cosine transform prototypes + + ********************************************************************/ + +#ifndef _OGG_mdct_H_ +#define _OGG_mdct_H_ + +#include "vorbis/codec.h" + + + + + +/*#define MDCT_INTEGERIZED <- be warned there could be some hurt left here*/ +#ifdef MDCT_INTEGERIZED + +#define DATA_TYPE int +#define REG_TYPE register int +#define TRIGBITS 14 +#define cPI3_8 6270 +#define cPI2_8 11585 +#define cPI1_8 15137 + +#define FLOAT_CONV(x) ((int)((x)*(1<<TRIGBITS)+.5)) +#define MULT_NORM(x) ((x)>>TRIGBITS) +#define HALVE(x) ((x)>>1) + +#else + +#define DATA_TYPE float +#define REG_TYPE float +#define cPI3_8 .38268343236508977175F +#define cPI2_8 .70710678118654752441F +#define cPI1_8 .92387953251128675613F + +#define FLOAT_CONV(x) (x) +#define MULT_NORM(x) (x) +#define HALVE(x) ((x)*.5f) + +#endif + + +typedef struct { + int n; + int log2n; + + DATA_TYPE *trig; + int *bitrev; + + DATA_TYPE scale; +} mdct_lookup; + +extern void mdct_init(mdct_lookup *lookup,int n); +extern void mdct_clear(mdct_lookup *l); +extern void mdct_forward(mdct_lookup *init, DATA_TYPE *in, DATA_TYPE *out); +extern void mdct_backward(mdct_lookup *init, DATA_TYPE *in, DATA_TYPE *out); + +#endif |