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Originally committed as revision 1630 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Michael Niedermayer 2003-03-06 10:08:15 +00:00
parent 2a5700de18
commit 24641185c1
1 changed files with 36 additions and 0 deletions
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36
libavcodec/dsputil.h
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@ -16,12 +16,20 @@
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/**
* @file dsputil.h
* @brief DSP utils
*
*/
#ifndef DSPUTIL_H
#define DSPUTIL_H
#include "common.h"
#include "avcodec.h"
//#define DEBUG
/* dct code */
typedef short DCTELEM;
@ -100,6 +108,9 @@ typedef int (*op_pixels_abs_func)(uint8_t *blk1/*align width (8 or 16)*/, uint8_
typedef int (*me_cmp_func)(void /*MpegEncContext*/ *s, uint8_t *blk1/*align width (8 or 16)*/, uint8_t *blk2/*align 1*/, int line_size)/* __attribute__ ((const))*/;
/**
* DSPContext.
*/
typedef struct DSPContext {
/* pixel ops : interface with DCT */
void (*get_pixels)(DCTELEM *block/*align 16*/, const uint8_t *pixels/*align 8*/, int line_size);
@ -152,8 +163,28 @@ typedef struct DSPContext {
/* (I)DCT */
void (*fdct)(DCTELEM *block/* align 16*/);
/**
* block -> idct -> clip to unsigned 8 bit -> dest.<br>
* (-1392, 0, 0, ...) -> idct -> (-174, -174, ...) -> put -> (0, 0, ...)
* @param line_size size in pixels of a horizotal line of dest
*/
void (*idct_put)(uint8_t *dest/*align 8*/, int line_size, DCTELEM *block/*align 16*/);
/**
* block -> idct -> add dest -> clip to unsigned 8 bit -> dest.
* @param line_size size in pixels of a horizotal line of dest
*/
void (*idct_add)(uint8_t *dest/*align 8*/, int line_size, DCTELEM *block/*align 16*/);
/**
* idct input permutation.<br>
* an example to avoid confusion:
* - (->decode coeffs -> zigzag reorder -> dequant -> reference idct ->...)
* - (x -> referece dct -> reference idct -> x)
* - (x -> referece dct -> simple_mmx_perm = idct_permutation -> simple_idct_mmx -> x)
* - (->decode coeffs -> zigzag reorder -> simple_mmx_perm -> dequant -> simple_idct_mmx ->...)
*/
uint8_t idct_permutation[64];
int idct_permutation_type;
#define FF_NO_IDCT_PERM 1
@ -171,6 +202,11 @@ void dsputil_init(DSPContext* p, AVCodecContext *avctx);
*/
void ff_block_permute(DCTELEM *block, uint8_t *permutation, const uint8_t *scantable, int last);
/**
* Empty mmx state.<br>
* this must be called between any dsp function and float/double code.
* for example sin(); dsp->idct_put(); emms_c(); cos()
*/
#define emms_c()
/* should be defined by architectures supporting