3D Data Denoising via Nonlocal Means Filter by Using Parallel GPU Strategies

Algorithm 3

CUDA code of NLM algorithm with partial unrolling strategy.

(1)    int  const  i_1  =   threadIdx.x   +   blockDim.x*blockIdx.x;

(2)   int  const  i_2  =   threadIdx.y   +  blockDim.y*blockIdx.y;

(3)       /*   local   statements   */

(4)       if   ((i_1   ≥   0)   &&   (i_1   <   X_Dim)   &&   (i_2  ≥   0)   &&   (i_2  <   Y_Dim))  {

(5)         for   (i_3   =   0;   i_3   <   Z_Dim;   i_3++)  {

(6)                   /*   compute   out_img   [i_1  +   i_2*X_Dim  +  i_3*X_Dim*Y_Dim]    using

     in_img  [i_1  +  i_2*X_Dim  +   i_3*X_Dim*Y_Dim]    */

(7)       } }