opencl/video-degradation.cl

   1 __kernel void gegl_video_degradation (__global const float4 *input,
   2                                       __global float4 *output,
   3                                       __global const int *pattern,
   4                                       const int pat_w,
   5                                       const int pat_h,
   6                                       const int additive,
   7                                       const int rotated)
   8 {
   9   const size_t gidx   = get_global_id(0);
  10   const size_t gidy   = get_global_id(1);
  11   const size_t gid    = gidx - get_global_offset(0) +
  12                        (gidy - get_global_offset(1)) *
  13                         get_global_size(0);
  14   const float4 indata = input[gid];
  15
  16   /* Get channel to keep in this input pixel */
  17   const int sel_b = pattern[rotated ? pat_w * (gidx % pat_h) + gidy % pat_w:
  18                                       pat_w * (gidy % pat_h) + gidx % pat_w];
  19
  20   /* Mask channels according to sel_b variable */
  21   float4 value = select(0.f, indata, sel_b == (int4)(0, 1, 2, 3));
  22
  23   /* Add original pixel if enabled */
  24   if (additive)
  25       value = fmin(value + indata, 1.0f);
  26
  27   /* Maintain original alpha channel */
  28   value.w = indata.w;
  29
  30   output[gid] = value;
  31 }