motion_comp.c

mpeg4代码,比较具体

/*****************************************************************************
 *
 *  XVID MPEG-4 VIDEO CODEC
 *  - Motion Compensation module -
 *
 *  Copyright(C) 2002 Peter Ross <[e-mail]>
 *
 *  This file is part of XviD, a free MPEG-4 video encoder/decoder
 *
 *  XviD 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 *  Under section 8 of the GNU General Public License, the copyright
 *  holders of XVID explicitly forbid distribution in the following
 *  countries:
 *
 *    - Japan
 *    - United States of America
 *
 *  Linking XviD statically or dynamically with other modules is making a
 *  combined work based on XviD.  Thus, the terms and conditions of the
 *  GNU General Public License cover the whole combination.
 *
 *  As a special exception, the copyright holders of XviD give you
 *  permission to link XviD with independent modules that communicate with
 *  XviD solely through the VFW1.1 and DShow interfaces, regardless of the
 *  license terms of these independent modules, and to copy and distribute
 *  the resulting combined work under terms of your choice, provided that
 *  every copy of the combined work is accompanied by a complete copy of
 *  the source code of XviD (the version of XviD used to produce the
 *  combined work), being distributed under the terms of the GNU General
 *  Public License plus this exception.  An independent module is a module
 *  which is not derived from or based on XviD.
 *
 *  Note that people who make modified versions of XviD are not obligated
 *  to grant this special exception for their modified versions; it is
 *  their choice whether to do so.  The GNU General Public License gives
 *  permission to release a modified version without this exception; this
 *  exception also makes it possible to release a modified version which
 *  carries forward this exception.
 *
 * $Id: motion_comp.c,v 1.16 2002/11/26 23:44:10 edgomez Exp $
 *
 *************************************************************************/

#include "../encoder.h"
#include "../utils/mbfunctions.h"
#include "../image/interpolate8x8.h"
#include "../utils/timer.h"
#include "motion.h"

#define ABS(X) (((X)>0)?(X):-(X))
#define SIGN(X) (((X)>0)?1:-1)

static __inline void
compensate8x8_halfpel(int16_t * const dct_codes,
					  uint8_t * const cur,
					  const uint8_t * const ref,
					  const uint8_t * const refh,
					  const uint8_t * const refv,
					  const uint8_t * const refhv,
					  const uint32_t x,
					  const uint32_t y,
					  const int32_t dx,
					  const int dy,
					  const uint32_t stride)
{
	int32_t ddx, ddy;

	switch (((dx & 1) << 1) + (dy & 1))	/* ((dx%2)?2:0)+((dy%2)?1:0) */
	{
	case 0:
		ddx = dx / 2;
		ddy = dy / 2;
		transfer_8to16sub(dct_codes, cur + y * stride + x,
						  ref + (int) ((y + ddy) * stride + x + ddx), stride);
		break;

	case 1:
		ddx = dx / 2;
		ddy = (dy - 1) / 2;
		transfer_8to16sub(dct_codes, cur + y * stride + x,
						  refv + (int) ((y + ddy) * stride + x + ddx), stride);
		break;

	case 2:
		ddx = (dx - 1) / 2;
		ddy = dy / 2;
		transfer_8to16sub(dct_codes, cur + y * stride + x,
						  refh + (int) ((y + ddy) * stride + x + ddx), stride);
		break;

	default:					/* case 3: */
		ddx = (dx - 1) / 2;
		ddy = (dy - 1) / 2;
		transfer_8to16sub(dct_codes, cur + y * stride + x,
						  refhv + (int) ((y + ddy) * stride + x + ddx), stride);
		break;
	}
}



void
MBMotionCompensation(MACROBLOCK * const mb,
					 const uint32_t i,
					 const uint32_t j,
					 const IMAGE * const ref,
					 const IMAGE * const refh,
					 const IMAGE * const refv,
					 const IMAGE * const refhv,
					 IMAGE * const cur,
					 int16_t * dct_codes,
					 const uint32_t width,
					 const uint32_t height,
					 const uint32_t edged_width,
					 const uint32_t rounding)
{
	static const uint32_t roundtab[16] =
		{ 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2 };


	if (mb->mode == MODE_INTER || mb->mode == MODE_INTER_Q) {
		int32_t dx = mb->mvs[0].x;
		int32_t dy = mb->mvs[0].y;

		compensate8x8_halfpel(&dct_codes[0 * 64], cur->y, ref->y, refh->y,
							  refv->y, refhv->y, 16 * i, 16 * j, dx, dy,
							  edged_width);
		compensate8x8_halfpel(&dct_codes[1 * 64], cur->y, ref->y, refh->y,
							  refv->y, refhv->y, 16 * i + 8, 16 * j, dx, dy,
							  edged_width);
		compensate8x8_halfpel(&dct_codes[2 * 64], cur->y, ref->y, refh->y,
							  refv->y, refhv->y, 16 * i, 16 * j + 8, dx, dy,
							  edged_width);
		compensate8x8_halfpel(&dct_codes[3 * 64], cur->y, ref->y, refh->y,
							  refv->y, refhv->y, 16 * i + 8, 16 * j + 8, dx,
							  dy, edged_width);

		dx = (dx & 3) ? (dx >> 1) | 1 : dx / 2;
		dy = (dy & 3) ? (dy >> 1) | 1 : dy / 2;

		/* uv-image-based compensation */

		interpolate8x8_switch(refv->u, ref->u, 8 * i, 8 * j, dx, dy,
							  edged_width / 2, rounding);
		transfer_8to16sub(&dct_codes[4 * 64],
						  cur->u + 8 * j * edged_width / 2 + 8 * i,
						  refv->u + 8 * j * edged_width / 2 + 8 * i,
						  edged_width / 2);

		interpolate8x8_switch(refv->v, ref->v, 8 * i, 8 * j, dx, dy,
							  edged_width / 2, rounding);
		transfer_8to16sub(&dct_codes[5 * 64],
						  cur->v + 8 * j * edged_width / 2 + 8 * i,
						  refv->v + 8 * j * edged_width / 2 + 8 * i,
						  edged_width / 2);

	} else						/* mode == MODE_INTER4V */
	{
		int32_t sum, dx, dy;

		compensate8x8_halfpel(&dct_codes[0 * 64], cur->y, ref->y, refh->y,
							  refv->y, refhv->y, 16 * i, 16 * j, mb->mvs[0].x,
							  mb->mvs[0].y, edged_width);
		compensate8x8_halfpel(&dct_codes[1 * 64], cur->y, ref->y, refh->y,
							  refv->y, refhv->y, 16 * i + 8, 16 * j,
							  mb->mvs[1].x, mb->mvs[1].y, edged_width);
		compensate8x8_halfpel(&dct_codes[2 * 64], cur->y, ref->y, refh->y,
							  refv->y, refhv->y, 16 * i, 16 * j + 8,
							  mb->mvs[2].x, mb->mvs[2].y, edged_width);
		compensate8x8_halfpel(&dct_codes[3 * 64], cur->y, ref->y, refh->y,
							  refv->y, refhv->y, 16 * i + 8, 16 * j + 8,
							  mb->mvs[3].x, mb->mvs[3].y, edged_width);

		sum = mb->mvs[0].x + mb->mvs[1].x + mb->mvs[2].x + mb->mvs[3].x;
		dx = (sum ? SIGN(sum) *
			  (roundtab[ABS(sum) % 16] + (ABS(sum) / 16) * 2) : 0);

		sum = mb->mvs[0].y + mb->mvs[1].y + mb->mvs[2].y + mb->mvs[3].y;
		dy = (sum ? SIGN(sum) *
			  (roundtab[ABS(sum) % 16] + (ABS(sum) / 16) * 2) : 0);

		/* uv-block-based compensation */
		interpolate8x8_switch(refv->u, ref->u, 8 * i, 8 * j, dx, dy,
							  edged_width / 2, rounding);
		transfer_8to16sub(&dct_codes[4 * 64],
						  cur->u + 8 * j * edged_width / 2 + 8 * i,
						  refv->u + 8 * j * edged_width / 2 + 8 * i,
						  edged_width / 2);

		interpolate8x8_switch(refv->v, ref->v, 8 * i, 8 * j, dx, dy,
							  edged_width / 2, rounding);
		transfer_8to16sub(&dct_codes[5 * 64],
						  cur->v + 8 * j * edged_width / 2 + 8 * i,
						  refv->v + 8 * j * edged_width / 2 + 8 * i,
						  edged_width / 2);
	}
}