libs/filters/GP_Convolution.c

   1 /*****************************************************************************
   2  * This file is part of gfxprim library.                                     *
   3  *                                                                           *
   4  * Gfxprim is free software; you can redistribute it and/or                  *
   5  * modify it under the terms of the GNU Lesser General Public                *
   6  * License as published by the Free Software Foundation; either              *
   7  * version 2.1 of the License, or (at your option) any later version.        *
   8  *                                                                           *
   9  * Gfxprim is distributed in the hope that it will be useful,                *
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of            *
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU         *
  12  * Lesser General Public License for more details.                           *
  13  *                                                                           *
  14  * You should have received a copy of the GNU Lesser General Public          *
  15  * License along with gfxprim; if not, write to the Free Software            *
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor,                        *
  17  * Boston, MA  02110-1301  USA                                               *
  18  *                                                                           *
  19  * Copyright (C) 2009-2012 Cyril Hrubis <metan@ucw.cz>                       *
  20  *                                                                           *
  21  *****************************************************************************/
  22
  23 #include "core/GP_Debug.h"
  24
  25 #include "GP_Linear.h"
  26
  27 #include "GP_Convolution.h"
  28 int GP_FilterConvolutionEx(const GP_Context *src,
  29                            GP_Coord x_src, GP_Coord y_src,
  30                            GP_Size w_src, GP_Coord h_src,
  31                            GP_Context *dst,
  32                            GP_Coord x_dst, GP_Coord y_dst,
  33                            const GP_FilterKernel2D *kernel,
  34                            GP_ProgressCallback *callback)
  35 {
  36         GP_CHECK(src->pixel_type == dst->pixel_type);
  37
  38         /* Check that destination is large enough */
  39         GP_CHECK(x_dst + (GP_Coord)w_src <= (GP_Coord)dst->w);
  40         GP_CHECK(y_dst + (GP_Coord)h_src <= (GP_Coord)dst->h);
  41
  42         /* The source pixel coordinates are clamped inside of the filter */
  43
  44         GP_DEBUG(1, "Linear convolution kernel size %ux%u",
  45                  kernel->w, kernel->h);
  46
  47         return GP_FilterLinearConvolution_Raw(src, x_src, y_src, w_src, h_src,
  48                                               dst, x_dst, y_dst, kernel->kernel,
  49                                               kernel->w, kernel->h, kernel->div,
  50                                               callback);
  51 }
  52
  53 GP_Context *GP_FilterConvolutionExAlloc(const GP_Context *src,
  54                                         GP_Coord x_src, GP_Coord y_src,
  55                                         GP_Size w_src, GP_Size h_src,
  56                                         const GP_FilterKernel2D *kernel,
  57                                         GP_ProgressCallback *callback)
  58 {
  59         GP_Context *ret = GP_ContextAlloc(w_src, h_src, src->pixel_type);
  60
  61         GP_DEBUG(1, "Linear convolution kernel size %ux%u",
  62                  kernel->w, kernel->h);
  63
  64         if (ret == NULL)
  65                 return NULL;
  66
  67         if (GP_FilterLinearConvolution_Raw(src, x_src, y_src, w_src, h_src,
  68                                            ret, 0, 0, kernel->kernel, kernel->w,
  69                                            kernel->h, kernel->div, callback)) {
  70                 GP_ContextFree(ret);
  71                 return NULL;
  72         }
  73
  74         return 0;
  75 }