slice.c

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#define bits (decoder->bitstream_bits)
#define bit_ptr (decoder->bitstream_ptr)
    NEEDBITS (bit_buf, bits, bit_ptr);
    /* Get the intra DC coefficient and inverse quantize it */
    #ifdef JZ4740_MXU_OPT
    /*
    if (cc == 0)
            decoder->dc_dct_pred[0] += get_luma_dc_dct_diff (decoder);
    else
            decoder->dc_dct_pred[cc] += get_chroma_dc_dct_diff (decoder);
        decoder->DCTblock[0] = decoder->dc_dct_pred[cc];*/
     if (cc == 0)
        decoder->dc_dct_pred[0] += get_luma_dc_dct_diff (decoder);
    else
        decoder->dc_dct_pred[cc] += get_chroma_dc_dct_diff (decoder);
    decoder->DCTblock[0] =
        decoder->dc_dct_pred[cc] << (3 -decoder->intra_dc_precision);     
   
    #else
    if (cc == 0)
        decoder->DCTblock[0] =
            decoder->dc_dct_pred[0] += get_luma_dc_dct_diff (decoder);
    else
        decoder->DCTblock[0] =
            decoder->dc_dct_pred[cc] += get_chroma_dc_dct_diff (decoder);
    #endif

    if (decoder->mpeg1) {
	if (decoder->coding_type != D_TYPE)
	    get_mpeg1_intra_block (decoder);
    } else if (decoder->intra_vlc_format)
	get_intra_block_B15 (decoder, decoder->quantizer_matrix[cc ? 2 : 0]);
    else
	get_intra_block_B14 (decoder, decoder->quantizer_matrix[cc ? 2 : 0]);
    mpeg2_idct_copy (decoder->DCTblock, dest, stride);
#undef bit_buf
#undef bits
#undef bit_ptr
}

static inline void slice_non_intra_DCT (mpeg2_decoder_t * const decoder,
					const int cc,
					uint8_t * const dest, const int stride)
{
    int last;

    if (decoder->mpeg1)
	last = get_mpeg1_non_intra_block (decoder);
    else
	last = get_non_intra_block (decoder,
				    decoder->quantizer_matrix[cc ? 3 : 1]);
    mpeg2_idct_add (last, decoder->DCTblock, dest, stride);
}

#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,			      \
	      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