dsputil.c
上传用户：jxp0626
上传日期：2007-01-08
资源大小：102k
文件大小：11k
- /*
- * DSP utils
- * Copyright (c) 2000 Gerard Lantau.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
- #include <stdlib.h>
- #include <stdio.h>
- #include "avcodec.h"
- #include "dsputil.h"
- #include "mpegvideo.h"
- #define avg2(a,b) ((a+b+1)>>1)
- #define avg4(a,b,c,d) ((a+b+c+d+2)>>2)
- static UINT8 cropTbl[256 + 2 * MAX_NEG_CROP];
- UINT32 squareTbl[512];
- void dsputil_init(void)
- {
- int i;
- for(i=0;i<256;i++) cropTbl[i + MAX_NEG_CROP] = i;
- for(i=0;i<MAX_NEG_CROP;i++) {
- cropTbl[i] = 0;
- cropTbl[i + MAX_NEG_CROP + 256] = 255;
- }
- for(i=0;i<512;i++) {
- squareTbl[i] = (i - 256) * (i - 256);
- }
- }
- void get_pixels(DCTELEM *block, const UINT8 *pixels, int line_size)
- {
- DCTELEM *p;
- const UINT8 *pix;
- int i;
- /* read the pixels */
- p = block;
- pix = pixels;
- for(i=0;i<8;i++) {
- p[0] = pix[0];
- p[1] = pix[1];
- p[2] = pix[2];
- p[3] = pix[3];
- p[4] = pix[4];
- p[5] = pix[5];
- p[6] = pix[6];
- p[7] = pix[7];
- pix += line_size;
- p += 8;
- }
- }
- void put_pixels(const DCTELEM *block, UINT8 *pixels, int line_size)
- {
- const DCTELEM *p;
- UINT8 *pix;
- int i;
- UINT8 *cm = cropTbl + MAX_NEG_CROP;
-
- /* read the pixels */
- p = block;
- pix = pixels;
- for(i=0;i<8;i++) {
- pix[0] = cm[p[0]];
- pix[1] = cm[p[1]];
- pix[2] = cm[p[2]];
- pix[3] = cm[p[3]];
- pix[4] = cm[p[4]];
- pix[5] = cm[p[5]];
- pix[6] = cm[p[6]];
- pix[7] = cm[p[7]];
- pix += line_size;
- p += 8;
- }
- }
- #define PIXOP(OPNAME, OP)
-
- static void OPNAME ## _pixels(DCTELEM *block, const UINT8 *pixels, int line_size)
- {
- DCTELEM *p;
- const UINT8 *pix;
- int i;
-
- p = block;
- pix = pixels;
- for(i=0;i<8;i++) {
- p[0] OP pix[0];
- p[1] OP pix[1];
- p[2] OP pix[2];
- p[3] OP pix[3];
- p[4] OP pix[4];
- p[5] OP pix[5];
- p[6] OP pix[6];
- p[7] OP pix[7];
- pix += line_size;
- p += 8;
- }
- }
-
- static void OPNAME ## _pixels_x2(DCTELEM *block, const UINT8 *pixels, int line_size)
- {
- DCTELEM *p;
- const UINT8 *pix;
- int i;
-
- p = block;
- pix = pixels;
- for(i=0;i<8;i++) {
- p[0] OP avg2(pix[0], pix[1]);
- p[1] OP avg2(pix[1], pix[2]);
- p[2] OP avg2(pix[2], pix[3]);
- p[3] OP avg2(pix[3], pix[4]);
- p[4] OP avg2(pix[4], pix[5]);
- p[5] OP avg2(pix[5], pix[6]);
- p[6] OP avg2(pix[6], pix[7]);
- p[7] OP avg2(pix[7], pix[8]);
- pix += line_size;
- p += 8;
- }
- }
-
- static void OPNAME ## _pixels_y2(DCTELEM *block, const UINT8 *pixels, int line_size)
- {
- DCTELEM *p;
- const UINT8 *pix;
- const UINT8 *pix1;
- int i;
-
- p = block;
- pix = pixels;
- pix1 = pixels + line_size;
- for(i=0;i<8;i++) {
- p[0] OP avg2(pix[0], pix1[0]);
- p[1] OP avg2(pix[1], pix1[1]);
- p[2] OP avg2(pix[2], pix1[2]);
- p[3] OP avg2(pix[3], pix1[3]);
- p[4] OP avg2(pix[4], pix1[4]);
- p[5] OP avg2(pix[5], pix1[5]);
- p[6] OP avg2(pix[6], pix1[6]);
- p[7] OP avg2(pix[7], pix1[7]);
- pix += line_size;
- pix1 += line_size;
- p += 8;
- }
- }
-
- static void OPNAME ## _pixels_xy2(DCTELEM *block, const UINT8 *pixels, int line_size)
- {
- DCTELEM *p;
- const UINT8 *pix;
- const UINT8 *pix1;
- int i;
-
- p = block;
- pix = pixels;
- pix1 = pixels + line_size;
- for(i=0;i<8;i++) {
- p[0] OP avg4(pix[0], pix[1], pix1[0], pix1[1]);
- p[1] OP avg4(pix[1], pix[2], pix1[1], pix1[2]);
- p[2] OP avg4(pix[2], pix[3], pix1[2], pix1[3]);
- p[3] OP avg4(pix[3], pix[4], pix1[3], pix1[4]);
- p[4] OP avg4(pix[4], pix[5], pix1[4], pix1[5]);
- p[5] OP avg4(pix[5], pix[6], pix1[5], pix1[6]);
- p[6] OP avg4(pix[6], pix[7], pix1[6], pix1[7]);
- p[7] OP avg4(pix[7], pix[8], pix1[7], pix1[8]);
- pix += line_size;
- pix1 += line_size;
- p += 8;
- }
- }
-
- void (*OPNAME ## _pixels_tab[4])(DCTELEM *block, const UINT8 *pixels, int line_size) = {
- OPNAME ## _pixels,
- OPNAME ## _pixels_x2,
- OPNAME ## _pixels_y2,
- OPNAME ## _pixels_xy2,
- };
- PIXOP(add, +=)
- PIXOP(sub, -=)
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