static inline int yv12touyvy_unscaled_altivec(SwsContext *c, uint8_t* src[], int srcStride[], int srcSliceY,

     int srcSliceH, uint8_t* dstParam[], int dstStride_a[]) {

  uint8_t *dst=dstParam[0] + dstStride_a[0]*srcSliceY;

  // yv12toyuy2( src[0],src[1],src[2],dst,c->srcW,srcSliceH,srcStride[0],srcStride[1],dstStride[0] );

  uint8_t *ysrc = src[0];

  uint8_t *usrc = src[1];

  uint8_t *vsrc = src[2];

  const int width = c->srcW;

  const int height = srcSliceH;

  const int lumStride = srcStride[0];

  const int chromStride = srcStride[1];

  const int dstStride = dstStride_a[0];

  const int vertLumPerChroma = 2;

  const vector unsigned char yperm = vec_lvsl(0, ysrc);

  register unsigned int y;



  if(width&15){

    yv12touyvy( ysrc, usrc, vsrc, dst,c->srcW,srcSliceH, lumStride, chromStride, dstStride);

    return srcSliceH;

  }



  /* this code assume:



  1) dst is 16 bytes-aligned

  2) dstStride is a multiple of 16

  3) width is a multiple of 16

  4) lum&chrom stride are multiple of 8

  */



  for(y=0; y<height; y++)

    {

      int i;

      for (i = 0; i < width - 31; i+= 32) {

	const unsigned int j = i >> 1;

	vector unsigned char v_yA = vec_ld(i, ysrc);

	vector unsigned char v_yB = vec_ld(i + 16, ysrc);

	vector unsigned char v_yC = vec_ld(i + 32, ysrc);

	vector unsigned char v_y1 = vec_perm(v_yA, v_yB, yperm);

	vector unsigned char v_y2 = vec_perm(v_yB, v_yC, yperm);

	vector unsigned char v_uA = vec_ld(j, usrc);

	vector unsigned char v_uB = vec_ld(j + 16, usrc);

	vector unsigned char v_u = vec_perm(v_uA, v_uB, vec_lvsl(j, usrc));

	vector unsigned char v_vA = vec_ld(j, vsrc);

	vector unsigned char v_vB = vec_ld(j + 16, vsrc);

	vector unsigned char v_v = vec_perm(v_vA, v_vB, vec_lvsl(j, vsrc));

	vector unsigned char v_uv_a = vec_mergeh(v_u, v_v);

	vector unsigned char v_uv_b = vec_mergel(v_u, v_v);

	vector unsigned char v_uyvy_0 = vec_mergeh(v_uv_a, v_y1);

	vector unsigned char v_uyvy_1 = vec_mergel(v_uv_a, v_y1);

	vector unsigned char v_uyvy_2 = vec_mergeh(v_uv_b, v_y2);

	vector unsigned char v_uyvy_3 = vec_mergel(v_uv_b, v_y2);

	vec_st(v_uyvy_0, (i << 1), dst);

	vec_st(v_uyvy_1, (i << 1) + 16, dst);

	vec_st(v_uyvy_2, (i << 1) + 32, dst);

	vec_st(v_uyvy_3, (i << 1) + 48, dst);

      }

      if (i < width) {

	const unsigned int j = i >> 1;

	vector unsigned char v_y1 = vec_ld(i, ysrc);

	vector unsigned char v_u = vec_ld(j, usrc);

	vector unsigned char v_v = vec_ld(j, vsrc);

	vector unsigned char v_uv_a = vec_mergeh(v_u, v_v);

	vector unsigned char v_uyvy_0 = vec_mergeh(v_uv_a, v_y1);

	vector unsigned char v_uyvy_1 = vec_mergel(v_uv_a, v_y1);

	vec_st(v_uyvy_0, (i << 1), dst);

	vec_st(v_uyvy_1, (i << 1) + 16, dst);

      }

      if((y&(vertLumPerChroma-1))==(vertLumPerChroma-1) )

	{

	  usrc += chromStride;

	  vsrc += chromStride;

	}

      ysrc += lumStride;

      dst += dstStride;

    }

  return srcSliceH;

}
