libs/filters/GP_Stats.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) 2009-2011 Cyril Hrubis <metan@ucw.cz>                       *
  20  *                                                                           *
  21  *****************************************************************************/
  22
  23 #include <string.h>
  24
  25 #include <GP_Debug.h>
  26
  27 #include "GP_Stats.h"
  28
  29 int GP_FilterHistogram_Raw(const GP_Context *src, GP_FilterParam histogram[],
  30                            GP_ProgressCallback *callback);
  31
  32 int GP_FilterHistogram(const GP_Context *src, GP_FilterParam histogram[],
  33                        GP_ProgressCallback *callback)
  34 {
  35         int ret;
  36
  37         ret = GP_FilterHistogram_Raw(src, histogram, callback);
  38
  39         if (ret)
  40                 return ret;
  41
  42         unsigned int i;
  43
  44         for (i = 0; histogram[i].channel_name[0] != '\0'; i++) {
  45                 unsigned int j;
  46                 GP_Histogram *hist = histogram[i].val.ptr;
  47
  48                 hist->max = hist->hist[0];
  49                 hist->min = hist->hist[0];
  50
  51                 for (j = 1; j < hist->len; j++) {
  52                         if (hist->hist[j] > hist->max)
  53                                 hist->max = hist->hist[j];
  54
  55                         if (hist->hist[j] < hist->min)
  56                                 hist->min = hist->hist[j];
  57                 }
  58         }
  59
  60         return 0;
  61 }
  62
  63 void GP_FilterHistogramAlloc(GP_PixelType type, GP_FilterParam params[])
  64 {
  65         uint32_t i;
  66
  67         GP_FilterParamSetPtrAll(params, NULL);
  68
  69         const GP_PixelTypeChannel *channels = GP_PixelTypes[type].channels;
  70
  71         for (i = 0; i < GP_PixelTypes[type].numchannels; i++) {
  72                 size_t chan_size = 1<<channels[i].size;
  73
  74                 GP_Histogram *hist = malloc(sizeof(struct GP_Histogram) +
  75                                             sizeof(uint32_t) * chan_size);
  76
  77                 if (hist == NULL) {
  78                         GP_FilterHistogramFree(params);
  79                         return;
  80                 }
  81
  82                 hist->len = chan_size;
  83                 memset(hist->hist, 0, sizeof(uint32_t) * chan_size);
  84
  85                 (GP_FilterParamChannel(params, channels[i].name))->val.ptr = hist;
  86         }
  87 }