/* $Id: f987f3c0bebbdea61b64ec05af91534c8c570a52 $
 * slice.c
 * Copyright (C) 2000-2003 Michel Lespinasse <walken@zoy.org>
 * Copyright (C) 2003      Peter Gubanov <peter@elecard.net.ru>
 * Copyright (C) 1999-2000 Aaron Holtzman <aholtzma@ess.engr.uvic.ca>
 *
 * This file is part of mpeg2dec, a free MPEG-2 video stream decoder.
 * See http://libmpeg2.sourceforge.net/ for updates.
 *
 * mpeg2dec 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.
 *
 * mpeg2dec 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
 */

#include "xxmc-config.h"

#include <inttypes.h>

#include "mpeg2.h"
#include "attributes.h"
#include "mpeg2_internal.h"

extern mpeg2_mc_t mpeg2_mc;
extern void (* mpeg2_cpu_state_save) (cpu_state_t * state);
extern void (* mpeg2_cpu_state_restore) (cpu_state_t * state);

#include "vlc.h"

static inline int get_motion_delta( mpeg2_decoder_t * const decoder,
				    const int f_code )
{
#define bit_buf (decoder->bitstream_buf)
#define bits (decoder->bitstream_bits)
#define bit_ptr (decoder->bitstream_ptr)

    int delta;
    int sign;
    const MVtab * tab;

    if( bit_buf & 0x80000000 )
    {
        DUMPBITS (bit_buf, bits, 1);
        return 0;
    }
    else if (bit_buf >= 0x0c000000)
    {
        tab = MV_4 + UBITS (bit_buf, 4);
        delta = (tab->delta << f_code) + 1;
        bits += tab->len + f_code + 1;
        bit_buf <<= tab->len;

        sign = SBITS (bit_buf, 1);
        bit_buf <<= 1;

        if (f_code)
            delta += UBITS (bit_buf, f_code);
        bit_buf <<= f_code;
        return (delta ^ sign) - sign;
    }
    else
    {
        tab = MV_10 + UBITS (bit_buf, 10);
        delta = (tab->delta << f_code) + 1;
        bits += tab->len + 1;
        bit_buf <<= tab->len;

        sign = SBITS (bit_buf, 1);
        bit_buf <<= 1;

        if (f_code)
        {
            NEEDBITS (bit_buf, bits, bit_ptr);
            delta += UBITS (bit_buf, f_code);
            DUMPBITS (bit_buf, bits, f_code);
        }

        return (delta ^ sign) - sign;
    }
#undef bit_buf
#undef bits
#undef bit_ptr
}

static inline int bound_motion_vector (const int vector, const int f_code)
{
    return ((int32_t)vector << (27 - f_code)) >> (27 - f_code);
}

static inline int get_dmv (mpeg2_decoder_t * const decoder)
{
#define bit_buf (decoder->bitstream_buf)
#define bits (decoder->bitstream_bits)
#define bit_ptr (decoder->bitstream_ptr)

    const DMVtab * tab;

    tab = DMV_2 + UBITS (bit_buf, 2);
    DUMPBITS (bit_buf, bits, tab->len);
    return tab->dmv;
#undef bit_buf
#undef bits
#undef bit_ptr
}

#define MOTION_420(table,ref,motion_x,motion_y,size,y)			      \
    pos_x = 2 * decoder->offset + motion_x;				      \
    pos_y = 2 * decoder->v_offset + motion_y + 2 * y;			      \
    if (unlikely (pos_x > decoder->limit_x)) {				      \
	pos_x = ((int)pos_x < 0) ? 0 : decoder->limit_x;		      \
	motion_x = pos_x - 2 * decoder->offset;				      \
    }									      \
    if (unlikely (pos_y > decoder->limit_y_ ## size)) {			      \
	pos_y = ((int)pos_y < 0) ? 0 : decoder->limit_y_ ## size;	      \
	motion_y = pos_y - 2 * decoder->v_offset - 2 * y;		      \
    }									      \
    xy_half = ((pos_y & 1) << 1) | (pos_x & 1);				      \
    table[xy_half] (decoder->dest[0] + y * decoder->stride + decoder->offset, \
		    ref[0] + (pos_x >> 1) + (pos_y >> 1) * decoder->stride,   \
		    decoder->stride, size);				      \
    motion_x /= 2;	motion_y /= 2;					      \
    xy_half = ((motion_y & 1) << 1) | (motion_x & 1);			      \
    offset = (((decoder->offset + motion_x) >> 1) +			      \
	      ((((decoder->v_offset + motion_y) >> 1) + y/2) *		      \
	       decoder->uv_stride));					      \
    table[4+xy_half] (decoder->dest[1] + y/2 * decoder->uv_stride +	      \
		      (decoder->offset >> 1), ref[1] + offset,		      \
		      decoder->uv_stride, size/2);			      \
    table[4+xy_half] (decoder->dest[2] + y/2 * decoder->uv_stride +	      \
		      (decoder->offset >> 1), ref[2] + offset,		      \
		      decoder->uv_stride, size/2)

#define MOTION_FIELD_420(table,ref,motion_x,motion_y,dest_field,op,src_field) \
    pos_x = 2 * decoder->offset + motion_x;				      \
    pos_y = decoder->v_offset + motion_y;				      \
    if (unlikely (pos_x > decoder->limit_x)) {				      \
	pos_x = ((int)pos_x < 0) ? 0 : decoder->limit_x;		      \
	motion_x = pos_x - 2 * decoder->offset;				      \
    }									      \
    if (unlikely (pos_y > decoder->limit_y)) {				      \
	pos_y = ((int)pos_y < 0) ? 0 : decoder->limit_y;		      \
	motion_y = pos_y - decoder->v_offset;				      \
    }									      \
    xy_half = ((pos_y & 1) << 1) | (pos_x & 1);				      \
    table[xy_half] (decoder->dest[0] + dest_field * decoder->stride +	      \
		    decoder->offset,					      \
		    (ref[0] + (pos_x >> 1) +				      \
		     ((pos_y op) + src_field) * decoder->stride),	      \
		    2 * decoder->stride, 8);				      \
    motion_x /= 2;	motion_y /= 2;					      \
    xy_half = ((motion_y & 1) << 1) | (motion_x & 1);			      \
    offset = (((decoder->offset + motion_x) >> 1) +			      \
	      (((decoder->v_offset >> 1) + (motion_y op) + src_field) *	      \
	       decoder->uv_stride));					      \
    table[4+xy_half] (decoder->dest[1] + dest_field * decoder->uv_stride +    \
		      (decoder->offset >> 1), ref[1] + offset,		      \
		      2 * decoder->uv_stride, 4);			      \
    table[4+xy_half] (decoder->dest[2] + dest_field * decoder->uv_stride +    \
		      (decoder->offset >> 1), ref[2] + offset,		      \
		      2 * decoder->uv_stride, 4)

#define MOTION_DMV_420(table,ref,motion_x,motion_y)			      \
    pos_x = 2 * decoder->offset + motion_x;				      \
    pos_y = decoder->v_offset + motion_y;				      \
    if (unlikely (pos_x > decoder->limit_x)) {				      \
	pos_x = ((int)pos_x < 0) ? 0 : decoder->limit_x;		      \
	motion_x = pos_x - 2 * decoder->offset;				      \
    }									      \
    if (unlikely (pos_y > decoder->limit_y)) {				      \
	pos_y = ((int)pos_y < 0) ? 0 : decoder->limit_y;		      \
	motion_y = pos_y - decoder->v_offset;				      \
    }									      \
    xy_half = ((pos_y & 1) << 1) | (pos_x & 1);				      \
    offset = (pos_x >> 1) + (pos_y & ~1) * decoder->stride;		      \
    table[xy_half] (decoder->dest[0] + decoder->offset,			      \
		    ref[0] + offset, 2 * decoder->stride, 8);		      \
    table[xy_half] (decoder->dest[0] + decoder->stride + decoder->offset,     \
		    ref[0] + decoder->stride + offset,			      \
		    2 * decoder->stride, 8);				      \
    motion_x /= 2;	motion_y /= 2;					      \
    xy_half = ((motion_y & 1) << 1) | (motion_x & 1);			      \
    offset = (((decoder->offset + motion_x) >> 1) +			      \
	      (((decoder->v_offset >> 1) + (motion_y & ~1)) *		      \
	       decoder->uv_stride));					      \
    table[4+xy_half] (decoder->dest[1] + (decoder->offset >> 1),	      \
		      ref[1] + offset, 2 * decoder->uv_stride, 4);	      \
    table[4+xy_half] (decoder->dest[1] + decoder->uv_stride +		      \
		      (decoder->offset >> 1),				      \
		      ref[1] + decoder->uv_stride + offset,		      \
		      2 * decoder->uv_stride, 4);			      \
    table[4+xy_half] (decoder->dest[2] + (decoder->offset >> 1),	      \
		      ref[2] + offset, 2 * decoder->uv_stride, 4);	      \
    table[4+xy_half] (decoder->dest[2] + decoder->uv_stride +		      \
		      (decoder->offset >> 1),				      \
		      ref[2] + decoder->uv_stride + offset,		      \
		      2 * decoder->uv_stride, 4)

#define MOTION_ZERO_420(table,ref)					      \
    table[0] (decoder->dest[0] + decoder->offset,			      \
	      (ref[0] + decoder->offset +				      \
	       decoder->v_offset * decoder->stride), decoder->stride, 16);    \
    offset = ((decoder->offset >> 1) +					      \
	      (decoder->v_offset >> 1) * decoder->uv_stride);		      \
    table[4] (decoder->dest[1] + (decoder->offset >> 1),		      \
	      ref[1] + offset, decoder->uv_stride, 8);			      \
    table[4] (decoder->dest[2] + (decoder->offset >> 1),		      \
	      ref[2] + offset, decoder->uv_stride, 8)

#define MOTION_422(table,ref,motion_x,motion_y,size,y)			      \
    pos_x = 2 * decoder->offset + motion_x;				      \
    pos_y = 2 * decoder->v_offset + motion_y + 2 * y;			      \
    if (unlikely (pos_x > decoder->limit_x)) {				      \
	pos_x = ((int)pos_x < 0) ? 0 : decoder->limit_x;		      \
	motion_x = pos_x - 2 * decoder->offset;				      \
    }									      \
    if (unlikely (pos_y > decoder->limit_y_ ## size)) {			      \
	pos_y = ((int)pos_y < 0) ? 0 : decoder->limit_y_ ## size;	      \
	motion_y = pos_y - 2 * decoder->v_offset - 2 * y;		      \
    }									      \
    xy_half = ((pos_y & 1) << 1) | (pos_x & 1);				      \
    offset = (pos_x >> 1) + (pos_y >> 1) * decoder->stride;		      \
    table[xy_half] (decoder->dest[0] + y * decoder->stride + decoder->offset, \
		    ref[0] + offset, decoder->stride, size);		      \
    offset = (offset + (motion_x & (motion_x < 0))) >> 1;		      \
    motion_x /= 2;							      \
    xy_half = ((pos_y & 1) << 1) | (motion_x & 1);			      \
    table[4+xy_half] (decoder->dest[1] + y * decoder->uv_stride +	      \
		      (decoder->offset >> 1), ref[1] + offset,		      \
		      decoder->uv_stride, size);			      \
    table[4+xy_half] (decoder->dest[2] + y * decoder->uv_stride +	      \
		      (decoder->offset >> 1), ref[2] + offset,		      \
		      decoder->uv_stride, size)

#define MOTION_FIELD_422(table,ref,motion_x,motion_y,dest_field,op,src_field) \
    pos_x = 2 * decoder->offset + motion_x;				      \
    pos_y = decoder->v_offset + motion_y;				      \
    if (unlikely (pos_x > decoder->limit_x)) {				      \
	pos_x = ((int)pos_x < 0) ? 0 : decoder->limit_x;		      \
	motion_x = pos_x - 2 * decoder->offset;				      \
    }									      \
    if (unlikely (pos_y > decoder->limit_y)) {				      \
	pos_y = ((int)pos_y < 0) ? 0 : decoder->limit_y;		      \
	motion_y = pos_y - decoder->v_offset;				      \
    }									      \
    xy_half = ((pos_y & 1) << 1) | (pos_x & 1);				      \
    offset = (pos_x >> 1) + ((pos_y op) + src_field) * decoder->stride;	      \
    table[xy_half] (decoder->dest[0] + dest_field * decoder->stride +	      \
		    decoder->offset, ref[0] + offset,			      \
		    2 * decoder->stride, 8);				      \
    offset = (offset + (motion_x & (motion_x < 0))) >> 1;		      \
    motion_x /= 2;							      \
    xy_half = ((pos_y & 1) << 1) | (motion_x & 1);			      \
    table[4+xy_half] (decoder->dest[1] + dest_field * decoder->uv_stride +    \
		      (decoder->offset >> 1), ref[1] + offset,		      \
		      2 * decoder->uv_stride, 8);			      \
    table[4+xy_half] (decoder->dest[2] + dest_field * decoder->uv_stride +    \
		      (decoder->offset >> 1), ref[2] + offset,		      \
		      2 * decoder->uv_stride, 8)

#define MOTION_DMV_422(table,ref,motion_x,motion_y)			      \
    pos_x = 2 * decoder->offset + motion_x;				      \
    pos_y = decoder->v_offset + motion_y;				      \
    if (unlikely (pos_x > decoder->limit_x)) {				      \
	pos_x = ((int)pos_x < 0) ? 0 : decoder->limit_x;		      \
	motion_x = pos_x - 2 * decoder->offset;				      \
    }									      \
    if (unlikely (pos_y > decoder->limit_y)) {				      \
	pos_y = ((int)pos_y < 0) ? 0 : decoder->limit_y;		      \
	motion_y = pos_y - decoder->v_offset;				      \
    }									      \
    xy_half = ((pos_y & 1) << 1) | (pos_x & 1);				      \
    offset = (pos_x >> 1) + (pos_y & ~1) * decoder->stride;		      \
    table[xy_half] (decoder->dest[0] + decoder->offset,			      \
		    ref[0] + offset, 2 * decoder->stride, 8);		      \
    table[xy_half] (decoder->dest[0] + decoder->stride + decoder->offset,     \
		    ref[0] + decoder->stride + offset,			      \
		    2 * decoder->stride, 8);				      \
    offset = (offset + (motion_x & (motion_x < 0))) >> 1;		      \
    motion_x /= 2;							      \
    xy_half = ((pos_y & 1) << 1) | (motion_x & 1);			      \
    table[4+xy_half] (decoder->dest[1] + (decoder->offset >> 1),	      \
		      ref[1] + offset, 2 * decoder->uv_stride, 8);	      \
    table[4+xy_half] (decoder->dest[1] + decoder->uv_stride +		      \
		      (decoder->offset >> 1),				      \
		      ref[1] + decoder->uv_stride + offset,		      \
		      2 * decoder->uv_stride, 8);			      \
    table[4+xy_half] (decoder->dest[2] + (decoder->offset >> 1),	      \
		      ref[2] + offset, 2 * decoder->uv_stride, 8);	      \
    table[4+xy_half] (decoder->dest[2] + decoder->uv_stride +		      \
		      (decoder->offset >> 1),				      \
		      ref[2] + decoder->uv_stride + offset,		      \
		      2 * decoder->uv_stride, 8)

#define MOTION_ZERO_422(table,ref)					      \
    offset = decoder->offset + decoder->v_offset * decoder->stride;	      \
    table[0] (decoder->dest[0] + decoder->offset,			      \
	      ref[0] + offset, decoder->stride, 16);			      \
    offset >>= 1;							      \
    table[4] (decoder->dest[1] + (decoder->offset >> 1),		      \
	      ref[1] + offset, decoder->uv_stride, 16);			      \
    table[4] (decoder->dest[2] + (decoder->offset >> 1),		      \
	      ref[2] + offset, decoder->uv_stride, 16)

#define MOTION_444(table,ref,motion_x,motion_y,size,y)			      \
    pos_x = 2 * decoder->offset + motion_x;				      \
    pos_y = 2 * decoder->v_offset + motion_y + 2 * y;			      \
    if (unlikely (pos_x > decoder->limit_x)) {				      \
	pos_x = ((int)pos_x < 0) ? 0 : decoder->limit_x;		      \
	motion_x = pos_x - 2 * decoder->offset;				      \
    }									      \
    if (unlikely (pos_y > decoder->limit_y_ ## size)) {			      \
	pos_y = ((int)pos_y < 0) ? 0 : decoder->limit_y_ ## size;	      \
	motion_y = pos_y - 2 * decoder->v_offset - 2 * y;		      \
    }									      \
    xy_half = ((pos_y & 1) << 1) | (pos_x & 1);				      \
    offset = (pos_x >> 1) + (pos_y >> 1) * decoder->stride;		      \
    table[xy_half] (decoder->dest[0] + y * decoder->stride + decoder->offset, \
		    ref[0] + offset, decoder->stride, size);		      \
    table[xy_half] (decoder->dest[1] + y * decoder->stride + decoder->offset, \
		    ref[1] + offset, decoder->stride, size);		      \
    table[xy_half] (decoder->dest[2] + y * decoder->stride + decoder->offset, \
		    ref[2] + offset, decoder->stride, size)

#define MOTION_FIELD_444(table,ref,motion_x,motion_y,dest_field,op,src_field) \
    pos_x = 2 * decoder->offset + motion_x;				      \
    pos_y = decoder->v_offset + motion_y;				      \
    if (unlikely (pos_x > decoder->limit_x)) {				      \
	pos_x = ((int)pos_x < 0) ? 0 : decoder->limit_x;		      \
	motion_x = pos_x - 2 * decoder->offset;				      \
    }									      \
    if (unlikely (pos_y > decoder->limit_y)) {				      \
	pos_y = ((int)pos_y < 0) ? 0 : decoder->limit_y;		      \
	motion_y = pos_y - decoder->v_offset;				      \
    }									      \
    xy_half = ((pos_y & 1) << 1) | (pos_x & 1);				      \
    offset = (pos_x >> 1) + ((pos_y op) + src_field) * decoder->stride;	      \
    table[xy_half] (decoder->dest[0] + dest_field * decoder->stride +	      \
		    decoder->offset, ref[0] + offset,			      \
		    2 * decoder->stride, 8);				      \
    table[xy_half] (decoder->dest[1] + dest_field * decoder->stride +	      \
		    decoder->offset, ref[1] + offset,			      \
		    2 * decoder->stride, 8);				      \
    table[xy_half] (decoder->dest[2] + dest_field * decoder->stride +	      \
		    decoder->offset, ref[2] + offset,			      \
		    2 * decoder->stride, 8)

#define MOTION_DMV_444(table,ref,motion_x,motion_y)			      \
    pos_x = 2 * decoder->offset + motion_x;				      \
    pos_y = decoder->v_offset + motion_y;				      \
    if (unlikely (pos_x > decoder->limit_x)) {				      \
	pos_x = ((int)pos_x < 0) ? 0 : decoder->limit_x;		      \
	motion_x = pos_x - 2 * decoder->offset;				      \
    }									      \
    if (unlikely (pos_y > decoder->limit_y)) {				      \
	pos_y = ((int)pos_y < 0) ? 0 : decoder->limit_y;		      \
	motion_y = pos_y - decoder->v_offset;				      \
    }									      \
    xy_half = ((pos_y & 1) << 1) | (pos_x & 1);				      \
    offset = (pos_x >> 1) + (pos_y & ~1) * decoder->stride;		      \
    table[xy_half] (decoder->dest[0] + decoder->offset,			      \
		    ref[0] + offset, 2 * decoder->stride, 8);		      \
    table[xy_half] (decoder->dest[0] + decoder->stride + decoder->offset,     \
		    ref[0] + decoder->stride + offset,			      \
		    2 * decoder->stride, 8);				      \
    table[xy_half] (decoder->dest[1] + decoder->offset,			      \
		    ref[1] + offset, 2 * decoder->stride, 8);		      \
    table[xy_half] (decoder->dest[1] + decoder->stride + decoder->offset,     \
		    ref[1] + decoder->stride + offset,			      \
		    2 * decoder->stride, 8);				      \
    table[xy_half] (decoder->dest[2] + decoder->offset,			      \
		    ref[2] + offset, 2 * decoder->stride, 8);		      \
    table[xy_half] (decoder->dest[2] + decoder->stride + decoder->offset,     \
		    ref[2] + decoder->stride + offset,			      \
		    2 * decoder->stride, 8)

#define MOTION_ZERO_444(table,ref)					      \
    offset = decoder->offset + decoder->v_offset * decoder->stride;	      \
    table[0] (decoder->dest[0] + decoder->offset,			      \
	      ref[0] + offset, decoder->stride, 16);			      \
    table[4] (decoder->dest[1] + decoder->offset,			      \
	      ref[1] + offset, decoder->stride, 16);			      \
    table[4] (decoder->dest[2] + (decoder->offset >> 1),		      \
	      ref[2] + offset, decoder->stride, 16)

#define bit_buf (decoder->bitstream_buf)
#define bits (decoder->bitstream_bits)
#define bit_ptr (decoder->bitstream_ptr)

static void motion_mp1 (mpeg2_decoder_t * const decoder,
			motion_t * const motion,
			mpeg2_mc_fct * const * const table)
{
    int motion_x, motion_y;
    unsigned int pos_x, pos_y, xy_half, offset;

    NEEDBITS (bit_buf, bits, bit_ptr);
    motion_x = (motion->pmv[0][0] +
               (get_motion_delta( decoder,
                                  motion->f_code[0] ) << motion->f_code[1]));
    motion_x = bound_motion_vector( motion_x,
                                    motion->f_code[0] + motion->f_code[1]);
    motion->pmv[0][0] = motion_x;

    NEEDBITS (bit_buf, bits, bit_ptr);
    motion_y = (motion->pmv[0][1] +
               (get_motion_delta( decoder,
                                  motion->f_code[0]) << motion->f_code[1]));
    motion_y = bound_motion_vector( motion_y,
                                    motion->f_code[0] + motion->f_code[1]);
    motion->pmv[0][1] = motion_y;
    MOTION_420 (table, motion->ref[0], motion_x, motion_y, 16, 0);
}

#define MOTION_FUNCTIONS(FORMAT,MOTION,MOTION_FIELD,MOTION_DMV,MOTION_ZERO)   \
									      \
static void motion_fr_frame_##FORMAT (mpeg2_decoder_t * const decoder,	      \
				      motion_t * const motion,		      \
				      mpeg2_mc_fct * const * const table)     \
{									      \
    int motion_x, motion_y;						      \
    unsigned int pos_x, pos_y, xy_half, offset;				      \
									      \
    NEEDBITS (bit_buf, bits, bit_ptr);					      \
    motion_x = motion->pmv[0][0] + get_motion_delta (decoder,		      \
						     motion->f_code[0]);      \
    motion_x = bound_motion_vector (motion_x, motion->f_code[0]);	      \
    motion->pmv[1][0] = motion->pmv[0][0] = motion_x;			      \
									      \
    NEEDBITS (bit_buf, bits, bit_ptr);					      \
    motion_y = motion->pmv[0][1] + get_motion_delta (decoder,		      \
						     motion->f_code[1]);      \
    motion_y = bound_motion_vector (motion_y, motion->f_code[1]);	      \
    motion->pmv[1][1] = motion->pmv[0][1] = motion_y;			      \
									      \
    MOTION (table, motion->ref[0], motion_x, motion_y, 16, 0);		      \
}									      \
									      \
static void motion_fr_field_##FORMAT (mpeg2_decoder_t * const decoder,	      \
				      motion_t * const motion,		      \
				      mpeg2_mc_fct * const * const table)     \
{									      \
    int motion_x, motion_y, field;					      \
    unsigned int pos_x, pos_y, xy_half, offset;				      \
									      \
    NEEDBITS (bit_buf, bits, bit_ptr);					      \
    field = UBITS (bit_buf, 1);						      \
    DUMPBITS (bit_buf, bits, 1);					      \
									      \
    motion_x = motion->pmv[0][0] + get_motion_delta (decoder,		      \
						     motion->f_code[0]);      \
    motion_x = bound_motion_vector (motion_x, motion->f_code[0]);	      \
    motion->pmv[0][0] = motion_x;					      \
									      \
    NEEDBITS (bit_buf, bits, bit_ptr);					      \
    motion_y = ((motion->pmv[0][1] >> 1) +				      \
		get_motion_delta (decoder, motion->f_code[1]));		      \
    /* motion_y = bound_motion_vector (motion_y, motion->f_code[1]); */	      \
    motion->pmv[0][1] = motion_y << 1;					      \
									      \
    MOTION_FIELD (table, motion->ref[0], motion_x, motion_y, 0, & ~1, field); \
									      \
    NEEDBITS (bit_buf, bits, bit_ptr);					      \
    field = UBITS (bit_buf, 1);						      \
    DUMPBITS (bit_buf, bits, 1);					      \
									      \
    motion_x = motion->pmv[1][0] + get_motion_delta (decoder,		      \
						     motion->f_code[0]);      \
    motion_x = bound_motion_vector (motion_x, motion->f_code[0]);	      \
    motion->pmv[1][0] = motion_x;					      \
									      \
    NEEDBITS (bit_buf, bits, bit_ptr);					      \
    motion_y = ((motion->pmv[1][1] >> 1) +				      \
		get_motion_delta (decoder, motion->f_code[1]));		      \
    /* motion_y = bound_motion_vector (motion_y, motion->f_code[1]); */	      \
    motion->pmv[1][1] = motion_y << 1;					      \
									      \
    MOTION_FIELD (table, motion->ref[0], motion_x, motion_y, 1, & ~1, field); \
}									      \
									      \
static void motion_fr_dmv_##FORMAT (mpeg2_decoder_t * const decoder,	      \
				    motion_t * const motion,		      \
				    mpeg2_mc_fct * const * const table)	      \
{									      \
    int motion_x, motion_y, dmv_x, dmv_y, m, other_x, other_y;		      \
    unsigned int pos_x, pos_y, xy_half, offset;				      \
									      \
    NEEDBITS (bit_buf, bits, bit_ptr);					      \
    motion_x = motion->pmv[0][0] + get_motion_delta (decoder,		      \
						     motion->f_code[0]);      \
    motion_x = bound_motion_vector (motion_x, motion->f_code[0]);	      \
    motion->pmv[1][0] = motion->pmv[0][0] = motion_x;			      \
    NEEDBITS (bit_buf, bits, bit_ptr);					      \
    dmv_x = get_dmv (decoder);						      \
									      \
    motion_y = ((motion->pmv[0][1] >> 1) +				      \
		get_motion_delta (decoder, motion->f_code[1]));		      \
    /* motion_y = bound_motion_vector (motion_y, motion->f_code[1]); */	      \
    motion->pmv[1][1] = motion->pmv[0][1] = motion_y << 1;		      \
    dmv_y = get_dmv (decoder);						      \
									      \
    m = decoder->top_field_first ? 1 : 3;				      \
    other_x = ((motion_x * m + (motion_x > 0)) >> 1) + dmv_x;		      \
    other_y = ((motion_y * m + (motion_y > 0)) >> 1) + dmv_y - 1;	      \
    MOTION_FIELD (mpeg2_mc.put, motion->ref[0], other_x, other_y, 0, | 1, 0); \
									      \
    m = decoder->top_field_first ? 3 : 1;				      \
    other_x = ((motion_x * m + (motion_x > 0)) >> 1) + dmv_x;		      \
    other_y = ((motion_y * m + (motion_y > 0)) >> 1) + dmv_y + 1;	      \
    MOTION_FIELD (mpeg2_mc.put, motion->ref[0], other_x, other_y, 1, & ~1, 0);\
									      \
    MOTION_DMV (mpeg2_mc.avg, motion->ref[0], motion_x, motion_y);	      \
}									      \
									      \
static void motion_reuse_##FORMAT (mpeg2_decoder_t * const decoder,	      \
				   motion_t * const motion,		      \
				   mpeg2_mc_fct * const * const table)	      \
{									      \
    int motion_x, motion_y;						      \
    unsigned int pos_x, pos_y, xy_half, offset;				      \
									      \
    motion_x = motion->pmv[0][0];					      \
    motion_y = motion->pmv[0][1];					      \
									      \
    MOTION (table, motion->ref[0], motion_x, motion_y, 16, 0);		      \
}									      \
									      \
static void motion_zero_##FORMAT (mpeg2_decoder_t * const decoder,	      \
				  motion_t * const motion,		      \
				  mpeg2_mc_fct * const * const table)	      \
{									      \
    unsigned int offset;						      \
									      \
    motion->pmv[0][0] = motion->pmv[0][1] = 0;				      \
    motion->pmv[1][0] = motion->pmv[1][1] = 0;				      \
									      \
    MOTION_ZERO (table, motion->ref[0]);				      \
}									      \
									      \
static void motion_fi_field_##FORMAT (mpeg2_decoder_t * const decoder,	      \
				      motion_t * const motion,		      \
				      mpeg2_mc_fct * const * const table)     \
{									      \
    int motion_x, motion_y;						      \
    uint8_t ** ref_field;						      \
    unsigned int pos_x, pos_y, xy_half, offset;				      \
									      \
    NEEDBITS (bit_buf, bits, bit_ptr);					      \
    ref_field = motion->ref2[UBITS (bit_buf, 1)];			      \
    DUMPBITS (bit_buf, bits, 1);					      \
									      \
    motion_x = motion->pmv[0][0] + get_motion_delta (decoder,		      \
						     motion->f_code[0]);      \
    motion_x = bound_motion_vector (motion_x, motion->f_code[0]);	      \
    motion->pmv[1][0] = motion->pmv[0][0] = motion_x;			      \
									      \
    NEEDBITS (bit_buf, bits, bit_ptr);					      \
    motion_y = motion->pmv[0][1] + get_motion_delta (decoder,		      \
						     motion->f_code[1]);      \
    motion_y = bound_motion_vector (motion_y, motion->f_code[1]);	      \
    motion->pmv[1][1] = motion->pmv[0][1] = motion_y;			      \
									      \
    MOTION (table, ref_field, motion_x, motion_y, 16, 0);		      \
}									      \
									      \
static void motion_fi_16x8_##FORMAT (mpeg2_decoder_t * const decoder,	      \
				     motion_t * const motion,		      \
				     mpeg2_mc_fct * const * const table)      \
{									      \
    int motion_x, motion_y;						      \
    uint8_t ** ref_field;						      \
    unsigned int pos_x, pos_y, xy_half, offset;				      \
									      \
    NEEDBITS (bit_buf, bits, bit_ptr);					      \
    ref_field = motion->ref2[UBITS (bit_buf, 1)];			      \
    DUMPBITS (bit_buf, bits, 1);					      \
									      \
    motion_x = motion->pmv[0][0] + get_motion_delta (decoder,		      \
						     motion->f_code[0]);      \
    motion_x = bound_motion_vector (motion_x, motion->f_code[0]);	      \
    motion->pmv[0][0] = motion_x;					      \
									      \
    NEEDBITS (bit_buf, bits, bit_ptr);					      \
    motion_y = motion->pmv[0][1] + get_motion_delta (decoder,		      \
						     motion->f_code[1]);      \
    motion_y = bound_motion_vector (motion_y, motion->f_code[1]);	      \
    motion->pmv[0][1] = motion_y;					      \
									      \
    MOTION (table, ref_field, motion_x, motion_y, 8, 0);		      \
									      \
    NEEDBITS (bit_buf, bits, bit_ptr);					      \
    ref_field = motion->ref2[UBITS (bit_buf, 1)];			      \
    DUMPBITS (bit_buf, bits, 1);					      \
									      \
    motion_x = motion->pmv[1][0] + get_motion_delta (decoder,		      \
						     motion->f_code[0]);      \
    motion_x = bound_motion_vector (motion_x, motion->f_code[0]);	      \
    motion->pmv[1][0] = motion_x;					      \
									      \
    NEEDBITS (bit_buf, bits, bit_ptr);					      \
    motion_y = motion->pmv[1][1] + get_motion_delta (decoder,		      \
						     motion->f_code[1]);      \
    motion_y = bound_motion_vector (motion_y, motion->f_code[1]);	      \
    motion->pmv[1][1] = motion_y;					      \
									      \
    MOTION (table, ref_field, motion_x, motion_y, 8, 8);		      \
}									      \
									      \
static void motion_fi_dmv_##FORMAT (mpeg2_decoder_t * const decoder,	      \
				    motion_t * const motion,		      \
				    mpeg2_mc_fct * const * const table)	      \
{									      \
    int motion_x, motion_y, other_x, other_y;				      \
    unsigned int pos_x, pos_y, xy_half, offset;				      \
									      \
    NEEDBITS (bit_buf, bits, bit_ptr);					      \
    motion_x = motion->pmv[0][0] + get_motion_delta (decoder,		      \
						     motion->f_code[0]);      \
    motion_x = bound_motion_vector (motion_x, motion->f_code[0]);	      \
    motion->pmv[1][0] = motion->pmv[0][0] = motion_x;			      \
    NEEDBITS (bit_buf, bits, bit_ptr);					      \
    other_x = ((motion_x + (motion_x > 0)) >> 1) + get_dmv (decoder);	      \
									      \
    motion_y = motion->pmv[0][1] + get_motion_delta (decoder,		      \
						     motion->f_code[1]);      \
    motion_y = bound_motion_vector (motion_y, motion->f_code[1]);	      \
    motion->pmv[1][1] = motion->pmv[0][1] = motion_y;			      \
    other_y = (((motion_y + (motion_y > 0)) >> 1) + get_dmv (decoder) +	      \
	       decoder->dmv_offset);					      \
									      \
    MOTION (mpeg2_mc.put, motion->ref[0], motion_x, motion_y, 16, 0);	      \
    MOTION (mpeg2_mc.avg, motion->ref[1], other_x, other_y, 16, 0);	      \
}									      \

MOTION_FUNCTIONS (420, MOTION_420, MOTION_FIELD_420, MOTION_DMV_420,
		  MOTION_ZERO_420)
MOTION_FUNCTIONS (422, MOTION_422, MOTION_FIELD_422, MOTION_DMV_422,
		  MOTION_ZERO_422)
MOTION_FUNCTIONS (444, MOTION_444, MOTION_FIELD_444, MOTION_DMV_444,
		  MOTION_ZERO_444)

/* like motion_frame, but parsing without actual motion compensation */
static void motion_fr_conceal (mpeg2_decoder_t * const decoder)
{
    int tmp;

    NEEDBITS (bit_buf, bits, bit_ptr);
    tmp = (decoder->f_motion.pmv[0][0] +
           get_motion_delta (decoder, decoder->f_motion.f_code[0]));
    tmp = bound_motion_vector (tmp, decoder->f_motion.f_code[0]);
    decoder->f_motion.pmv[1][0] = decoder->f_motion.pmv[0][0] = tmp;

    NEEDBITS (bit_buf, bits, bit_ptr);
    tmp = (decoder->f_motion.pmv[0][1] +
           get_motion_delta (decoder, decoder->f_motion.f_code[1]));
    tmp = bound_motion_vector (tmp, decoder->f_motion.f_code[1]);
    decoder->f_motion.pmv[1][1] = decoder->f_motion.pmv[0][1] = tmp;

    DUMPBITS (bit_buf, bits, 1); /* remove marker_bit */
}

static void motion_fi_conceal (mpeg2_decoder_t * const decoder)
{
    int tmp;

    NEEDBITS (bit_buf, bits, bit_ptr);
    DUMPBITS (bit_buf, bits, 1); /* remove field_select */

    tmp = (decoder->f_motion.pmv[0][0] +
           get_motion_delta (decoder, decoder->f_motion.f_code[0]));
    tmp = bound_motion_vector (tmp, decoder->f_motion.f_code[0]);
    decoder->f_motion.pmv[1][0] = decoder->f_motion.pmv[0][0] = tmp;

    NEEDBITS (bit_buf, bits, bit_ptr);
    tmp = (decoder->f_motion.pmv[0][1] +
           get_motion_delta (decoder, decoder->f_motion.f_code[1]));
    tmp = bound_motion_vector (tmp, decoder->f_motion.f_code[1]);
    decoder->f_motion.pmv[1][1] = decoder->f_motion.pmv[0][1] = tmp;

    DUMPBITS (bit_buf, bits, 1); /* remove marker_bit */
}

#undef bit_buf
#undef bits
#undef bit_ptr

#define MOTION_CALL(routine,direction)				\
do {								\
    if ((direction) & MACROBLOCK_MOTION_FORWARD)		\
	routine (decoder, &(decoder->f_motion), mpeg2_mc.put);	\
    if ((direction) & MACROBLOCK_MOTION_BACKWARD)		\
	routine (decoder, &(decoder->b_motion),			\
		 ((direction) & MACROBLOCK_MOTION_FORWARD ?	\
		  mpeg2_mc.avg : mpeg2_mc.put));		\
} while (0)

#define NEXT_MACROBLOCK							\
do {									\
    decoder->offset += 16;						\
    if (decoder->offset == decoder->width) {				\
	do { /* just so we can use the break statement */		\
	    if (decoder->convert) {					\
		decoder->convert (decoder->convert_id, decoder->dest,	\
				  decoder->v_offset);			\
		if (decoder->coding_type == B_TYPE)			\
		    break;						\
	    }								\
	    decoder->dest[0] += decoder->slice_stride;			\
	    decoder->dest[1] += decoder->slice_uv_stride;		\
	    decoder->dest[2] += decoder->slice_uv_stride;		\
	} while (0);							\
	decoder->v_offset += 16;					\
	if (decoder->v_offset > decoder->limit_y) {			\
	    if (mpeg2_cpu_state_restore)				\
		mpeg2_cpu_state_restore (&cpu_state);			\
	    return;							\
	}								\
	decoder->offset = 0;						\
    }									\
} while (0)

void mpeg2_init_fbuf (mpeg2_decoder_t * decoder, uint8_t * current_fbuf[3],
		      uint8_t * forward_fbuf[3], uint8_t * backward_fbuf[3])
{
    int offset, stride, height, bottom_field;

    stride = decoder->stride_frame;
    bottom_field = (decoder->picture_structure == BOTTOM_FIELD);
    offset = bottom_field ? stride : 0;
    height = decoder->height;

    decoder->picture_dest[0] = current_fbuf[0] + offset;
    decoder->picture_dest[1] = current_fbuf[1] + (offset >> 1);
    decoder->picture_dest[2] = current_fbuf[2] + (offset >> 1);

    decoder->f_motion.ref[0][0] = forward_fbuf[0] + offset;
    decoder->f_motion.ref[0][1] = forward_fbuf[1] + (offset >> 1);
    decoder->f_motion.ref[0][2] = forward_fbuf[2] + (offset >> 1);

    decoder->b_motion.ref[0][0] = backward_fbuf[0] + offset;
    decoder->b_motion.ref[0][1] = backward_fbuf[1] + (offset >> 1);
    decoder->b_motion.ref[0][2] = backward_fbuf[2] + (offset >> 1);

    if( decoder->picture_structure != FRAME_PICTURE )
    {
        decoder->dmv_offset = bottom_field ? 1 : -1;
        decoder->f_motion.ref2[0] = decoder->f_motion.ref[bottom_field];
        decoder->f_motion.ref2[1] = decoder->f_motion.ref[!bottom_field];
        decoder->b_motion.ref2[0] = decoder->b_motion.ref[bottom_field];
        decoder->b_motion.ref2[1] = decoder->b_motion.ref[!bottom_field];
        offset = stride - offset;

        if( decoder->second_field && (decoder->coding_type != B_TYPE) )
            forward_fbuf = current_fbuf;

        decoder->f_motion.ref[1][0] = forward_fbuf[0] + offset;
        decoder->f_motion.ref[1][1] = forward_fbuf[1] + (offset >> 1);
        decoder->f_motion.ref[1][2] = forward_fbuf[2] + (offset >> 1);

        decoder->b_motion.ref[1][0] = backward_fbuf[0] + offset;
        decoder->b_motion.ref[1][1] = backward_fbuf[1] + (offset >> 1);
        decoder->b_motion.ref[1][2] = backward_fbuf[2] + (offset >> 1);

        stride <<= 1;
        height >>= 1;
    }

    decoder->stride = stride;
    decoder->uv_stride = stride >> 1;
    decoder->slice_stride = 16 * stride;
    decoder->slice_uv_stride =
    decoder->slice_stride >> (2 - decoder->chroma_format);
    decoder->limit_x = 2 * decoder->width - 32;
    decoder->limit_y_16 = 2 * height - 32;
    decoder->limit_y_8 = 2 * height - 16;
    decoder->limit_y = height - 16;

    if( decoder->mpeg1 )
    {
        decoder->motion_parser[0] = motion_zero_420;
        decoder->motion_parser[MC_FRAME] = motion_mp1;
        decoder->motion_parser[4] = motion_reuse_420;
    }
    else if( decoder->picture_structure == FRAME_PICTURE )
    {
        if (decoder->chroma_format == 0)
        {
            decoder->motion_parser[0] = motion_zero_420;
            decoder->motion_parser[MC_FIELD] = motion_fr_field_420;
            decoder->motion_parser[MC_FRAME] = motion_fr_frame_420;
            decoder->motion_parser[MC_DMV] = motion_fr_dmv_420;
            decoder->motion_parser[4] = motion_reuse_420;
        }
        else if (decoder->chroma_format == 1)
        {
            decoder->motion_parser[0] = motion_zero_422;
            decoder->motion_parser[MC_FIELD] = motion_fr_field_422;
            decoder->motion_parser[MC_FRAME] = motion_fr_frame_422;
            decoder->motion_parser[MC_DMV] = motion_fr_dmv_422;
            decoder->motion_parser[4] = motion_reuse_422;
        } else
        {
            decoder->motion_parser[0] = motion_zero_444;
            decoder->motion_parser[MC_FIELD] = motion_fr_field_444;
            decoder->motion_parser[MC_FRAME] = motion_fr_frame_444;
            decoder->motion_parser[MC_DMV] = motion_fr_dmv_444;
            decoder->motion_parser[4] = motion_reuse_444;
        }
    }
    else
    {
        if (decoder->chroma_format == 0)
        {
            decoder->motion_parser[0] = motion_zero_420;
            decoder->motion_parser[MC_FIELD] = motion_fi_field_420;
            decoder->motion_parser[MC_16X8] = motion_fi_16x8_420;
            decoder->motion_parser[MC_DMV] = motion_fi_dmv_420;
            decoder->motion_parser[4] = motion_reuse_420;
        }
        else if (decoder->chroma_format == 1)
        {
            decoder->motion_parser[0] = motion_zero_422;
            decoder->motion_parser[MC_FIELD] = motion_fi_field_422;
            decoder->motion_parser[MC_16X8] = motion_fi_16x8_422;
            decoder->motion_parser[MC_DMV] = motion_fi_dmv_422;
            decoder->motion_parser[4] = motion_reuse_422;
        }
        else
        {
            decoder->motion_parser[0] = motion_zero_444;
            decoder->motion_parser[MC_FIELD] = motion_fi_field_444;
            decoder->motion_parser[MC_16X8] = motion_fi_16x8_444;
            decoder->motion_parser[MC_DMV] = motion_fi_dmv_444;
            decoder->motion_parser[4] = motion_reuse_444;
        }
    }
}
