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Implement the discrete sine/cosine transforms DCT-I and DST-I

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Originally committed as revision 22649 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Vitor Sessak
2010-03-23 19:48:16 +00:00
parent be548816dc
commit e1484ebed6
5 changed files with 93 additions and 16 deletions
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11
libavcodec/fft.h
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@ -226,11 +226,14 @@ struct DCTContext {
};
/**
* Sets up (Inverse)DCT.
* @param nbits log2 of the length of the input array
* @param inverse >0 forward transform, <0 inverse transform
* Sets up DCT.
* @param nbits size of the input array:
* (1 << nbits) for DCT-II, DCT-III and DST-I
* (1 << nbits) + 1 for DCT-I
*
* @note the first element of the input of DST-I is ignored
*/
int ff_dct_init(DCTContext *s, int nbits, int inverse);
int ff_dct_init(DCTContext *s, int nbits, enum DCTTransformType type);
void ff_dct_calc(DCTContext *s, FFTSample *data);
void ff_dct_end (DCTContext *s);