opencl/contrast-curve.cl

   1 /* This file is an image processing operation for GEGL
   2  *
   3  * GEGL is free software; you can redistribute it and/or
   4  * modify it under the terms of the GNU Lesser General Public
   5  * License as published by the Free Software Foundation; either
   6  * version 3 of the License, or (at your option) any later version.
   7  *
   8  * GEGL is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * Lesser General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU Lesser General Public
  14  * License along with GEGL; if not, see <https://www.gnu.org/licenses/>.
  15  *
  16  * Copyright 2013 Carlos Zubieta <czubieta.dev@gmail.com>
  17  */
  18
  19 __kernel void cl_contrast_curve(__global const float2 *in,
  20                                 __global       float2 *out,
  21                                 __global       float  *curve,
  22                                                int     num_sampling_points)
  23 {
  24   int gid     = get_global_id(0);
  25   float2 in_v = in[gid];
  26
  27   int idx = (int) fmin(num_sampling_points - 1.0f,
  28                        fmax(0.0f,
  29                             in_v.x * num_sampling_points));
  30
  31   out[gid] = (float2) (curve[idx], in_v.y);
  32 }
  33