git.sesse.net Git - kdenlive/blob - src/v4l/dec_bayer.c

   1 /* fswebcam - Small and simple webcam for *nix                */
   2 /*============================================================*/
   3 /* Copyright (C)2005-2010 Philip Heron <phil@sanslogic.co.uk> */
   4 /*                                                            */
   5 /* This program is distributed under the terms of the GNU     */
   6 /* General Public License, version 2. You may use, modify,    */
   7 /* and redistribute it under the terms of this license. A     */
   8 /* copy should be included with this source.                  */
   9
  10 #ifdef HAVE_CONFIG_H
  11 #include "config.h"
  12 #endif
  13
  14 #include <stdint.h>
  15 /*#include "fswebcam.h"*/
  16 #include "src.h"
  17
  18
  19 int fswc_add_image_bayer(avgbmp_t *dst, uint8_t *img, uint32_t length, uint32_t w, uint32_t h, int palette)
  20 {
  21         uint32_t x = 0, y = 0;
  22         uint32_t i = w * h;
  23
  24         if(length < i) return(-1);
  25
  26         /* SBGGR8 bayer pattern:
  27          *
  28          * BGBGBGBGBG
  29          * GRGRGRGRGR
  30          * BGBGBGBGBG
  31          * GRGRGRGRGR
  32          *
  33          * SGBRG8 bayer pattern:
  34          *
  35          * GBGBGBGBGB
  36          * RGRGRGRGRG
  37          * GBGBGBGBGB
  38          * RGRGRGRGRG
  39          *
  40          * SGRBG8 bayer pattern:
  41          *
  42          * GRGRGRGRGR
  43          * BGBGBGBGBG
  44          * GRGRGRGRGR
  45          * BGBGBGBGBG
  46         */
  47
  48         while(i-- > 0)
  49         {
  50                 uint8_t *p[8];
  51                 uint8_t hn, vn, di;
  52                 uint8_t r, g, b;
  53                 int mode;
  54
  55                 /* Setup pointers to this pixel's neighbours. */
  56                 p[0] = img - w - 1;
  57                 p[1] = img - w;
  58                 p[2] = img - w + 1;
  59                 p[3] = img - 1;
  60                 p[4] = img + 1;
  61                 p[5] = img + w - 1;
  62                 p[6] = img + w;
  63                 p[7] = img + w + 1;
  64
  65                 /* Juggle pointers if they are out of bounds. */
  66                 if(!y)              { p[0]=p[5]; p[1]=p[6]; p[2]=p[7]; }
  67                 else if(y == h - 1) { p[5]=p[0]; p[6]=p[1]; p[7]=p[2]; }
  68                 if(!x)              { p[0]=p[2]; p[3]=p[4]; p[5]=p[7]; }
  69                 else if(x == w - 1) { p[2]=p[0]; p[4]=p[3]; p[7]=p[5]; }
  70
  71                 /* Average matching neighbours. */
  72                 hn = (*p[3] + *p[4]) / 2;
  73                 vn = (*p[1] + *p[6]) / 2;
  74                 di = (*p[0] + *p[2] + *p[5] + *p[7]) / 4;
  75
  76                 /* Calculate RGB */
  77                 if(palette == SRC_PAL_BAYER) mode = (x + y) & 0x01;
  78                 else mode = ~(x + y) & 0x01;
  79
  80                 if(mode)
  81                 {
  82                         g = *img;
  83                         if(y & 0x01) { r = hn; b = vn; }
  84                         else         { r = vn; b = hn; }
  85                 }
  86                 else if(y & 0x01) { r = *img; g = (vn + hn) / 2; b = di; }
  87                 else              { b = *img; g = (vn + hn) / 2; r = di; }
  88
  89                 if(palette == SRC_PAL_SGRBG8)
  90                 {
  91                         uint8_t t = r;
  92                         r = b;
  93                         b = t;
  94                 }
  95
  96                 *(dst++) += r;
  97                 *(dst++) += g;
  98                 *(dst++) += b;
  99
 100                 /* Move to the next pixel (or line) */
 101                 if(++x == w) { x = 0; y++; }
 102                 img++;
 103         }
 104
 105         return(0);
 106 }
 107