sobel filter by using 2D image interface opencl

I made a simple image sobel filter application using 2D interfacing example.
Firt add sobel filter kernel into imagecpy.cl file and create sobel filter kernel instead of image2d_copier.

__kernel void sobel_rgb(read_only image2d_t src, write_only image2d_t dst, sampler_t sampler)
{
  int x = (int)get_global_id(0); int y = (int)get_global_id(1);
 
  float4 p00 = read_imagef(src, sampler, (int2)(x - 1, y-1));
  float4 p10 = read_imagef(src, sampler, (int2)(x, y-1));
  float4 p20 = read_imagef(src, sampler, (int2)(x + 1, y-1));
  float4 p01 = read_imagef(src, sampler, (int2)(x - 1, y));
  float4 p21 = read_imagef(src, sampler, (int2)(x + 1, y));
  float4 p02 = read_imagef(src, sampler, (int2)(x - 1, y+1));
  float4 p12 = read_imagef(src, sampler, (int2)(x, y+1));
  float4 p22 = read_imagef(src, sampler, (int2)(x + 1, y + 1));
 
  float3 gx = -p00.xyz + p20.xyz + 2.0f * (p21.xyz - p01.xyz) - p02.xyz + p22.xyz;
  float3 gy = -p00.xyz - p20.xyz + 2.0f * (p12.xyz - p10.xyz) + p02.xyz + p22.xyz;
  float3 norm = gx * gx + gy * gy;
  float3 g = native_sqrt(norm.x+norm.y+norm.z);
  write_imagef(dst, (int2)(x, y), (float4)(g.x, g.y, g.z, 1.0f));
 
}

I got the result as below

참 쉽죠~~