device/ov7620_raw_linear.h

   1 // Copyright 2003, 2004 David Hilvert <dhilvert@auricle.dyndns.org>,
   2 //                                    <dhilvert@ugcs.caltech.edu>
   3
   4 /*  This file is part of the Anti-Lamenessing Engine.
   5
   6     The Anti-Lamenessing Engine is free software; you can redistribute it
   7     and/or modify it under the terms of the GNU General Public License as
   8     published by the Free Software Foundation; either version 3 of the License,
   9     or (at your option) any later version.
  10
  11     The Anti-Lamenessing Engine is distributed in the hope that it will be
  12     useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
  14     Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with the Anti-Lamenessing Engine; if not, write to the Free Software
  18     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19 */
  20
  21 #ifndef __ov7620_raw_linear_h__
  22 #define __ov7620_raw_linear_h__
  23
  24 #include "../d2.h"
  25
  26 /*
  27  * Device module for the OmniView OV7620 chip.
  28  *
  29  * This module is designed for use with the Linux 2.6.x driver patched with
  30  * code available at:
  31  *
  32  * http://auricle.dyndns.org/ov7620/
  33  *
  34  */
  35
  36 class ov7620_raw_linear {
  37 public:
  38
  39         /*
  40          * Linear colorspace PSF
  41          */
  42
  43         class lpsf : public d2::box {
  44         public:
  45                 /*
  46                  * A box filter of diameter ~0.6325 results in an optical fill
  47                  * factor of 40%.  Experimentation shows that filters of about
  48                  * this size perform well with this sensor, and the fill factor
  49                  * value matches data available on the web about this sensor:
  50                  *
  51                  * http://www.stanford.edu/class/ee109/reference/camera/DS-OV7620-1.3.pdf
  52                  */
  53
  54                 lpsf() : d2::box (0.3162) {
  55                 }
  56         };
  57
  58         /*
  59          * Exposure
  60          */
  61
  62         class exposure : public d2::exposure_default {
  63                 d2::pixel linearize(d2::pixel input) const {
  64                         ale_real lo = 16 / (ale_real) 255;
  65                         ale_real scale = 255 / (ale_real) 224;
  66                         return (input - d2::pixel(lo, lo, lo)) * scale * get_multiplier();
  67                 }
  68                 d2::pixel unlinearize(d2::pixel input) const {
  69                         ale_real lo = 16 / (ale_real) 255;
  70                         ale_real scale = 224 / (ale_real) 255;
  71                         return (input / get_multiplier()) * scale + d2::pixel(lo, lo, lo);
  72                 }
  73         };
  74
  75         /*
  76          * View Angle
  77          */
  78
  79         static ale_pos view_angle() {
  80                 fprintf(stderr, "\n\n*** Error: tried to obtain view angle for a sensor device. ***\n\n");
  81                 exit(1);
  82                 // return 30;
  83         }
  84 };
  85
  86 #undef LPSF_ROWS
  87 #undef LPSF_COLS
  88 #undef NLPSF_ROWS
  89 #undef NLPSF_COLS
  90
  91 #endif