[Summary view] [Print] [Text view]

   1  <?php
   2  
   3  //Made by Chao Xu(Mgccl) 3/1/07
   4  //www.webdevlogs.com
   5  //V 1.0
   6  
   7  // Drupal code style and some restructuring by dopry. http://www.darrelopry.com
   8  
   9  
  10  define('IMG_FILTER_NEGATE', 0);
  11  define('IMG_FILTER_GRAYSCALE', 1);
  12  define('IMG_FILTER_BRIGHTNESS', 2);
  13  define('IMG_FILTER_CONTRAST', 3);
  14  define('IMG_FILTER_COLORIZE', 4);
  15  define('IMG_FILTER_EDGEDETECT', 5);
  16  define('IMG_FILTER_EMBOSS', 6);
  17  define('IMG_FILTER_GAUSSIAN_BLUR', 7);
  18  define('IMG_FILTER_SELECTIVE_BLUR', 8);
  19  define('IMG_FILTER_MEAN_REMOVAL', 9);
  20  define('IMG_FILTER_SMOOTH', 10);
  21  
  22  define('IMAGEAPI_IMAGEFILTER_PHP', 1);
  23  /**
  24   * walk each pixel in an image applying $callback to it.
  25   */
  26  function _imageapi_gd_pixel_color_walk(&$im, $callback, $arg1 = NULL, $arg2 = NULL, $arg3 = NULL, $arg4 = NULL) {
  27    $max_y = imagesy($im);
  28    $max_x = imagesx($im);
  29    for ($y=0; $y < $max_y; ++$y) {
  30      for ($x=0; $x < $max_x; ++$x) {
  31        $rgb = imagecolorat($im, $x, $y);
  32        $r = ($rgb >> 16) & 0xFF;
  33        $g = ($rgb >> 8) & 0xFF;
  34        $b = ($rgb & 0xFF);
  35        $a = $rgb >> 24;
  36  
  37        $callback($r, $g, $b, $a, $arg1, $arg2, $arg3, $arg4);
  38  
  39        // sanitize rgb values.
  40        $r = ($r > 255)? 255 : (($r < 0)? 0:$r);
  41        $g = ($g > 255)? 255 : (($g < 0)? 0:$g);
  42        $b = ($b > 255)? 255 : (($b < 0)? 0:$b);
  43        $a = ($a > 127)? 127 : (($a < 0)? 0:$a);
  44  
  45        if (!$color = imagecolorallocatealpha($im, $r, $g, $b, $a)) {
  46          $color = imagecolorclosestalpha($im, $r, $g, $b, $a);
  47        }
  48        imagesetpixel($im, $x, $y, $color);
  49      }
  50    }
  51  }
  52  
  53  function _imageapi_gd_pixel_negate(&$r, &$g, &$b, &$a) {
  54    $r = 255 - $r;
  55    $g = 255 - $g;
  56    $b = 255 - $b;
  57  }
  58  
  59  
  60  function _imageapi_gd_pixel_grayscale(&$r, &$g, &$b, &$a) {
  61    $r = round($r * 0.299 + $g * 0.587 + $b * 0.114);
  62    $g = $r;
  63    $b = $r;
  64  }
  65  
  66  function _imageapi_gd_pixel_brightness(&$r, &$g, &$b, &$a, $arg1) {
  67    $r += $arg1;
  68    $g += $arg1;
  69    $b += $arg1;
  70  }
  71  
  72  function _imageapi_gd_pixel_contrast(&$r, &$g, &$b, &$a, $contrast) {
  73    // normalize color value between -0.5 - 0.5
  74    // multiply by contrast value to accentuate positive/negative value.
  75    // denormalize to 0-255 range.
  76    $r = ((($r/255 - 0.5) * $contrast) + 0.5) * 255;
  77    $g = ((($g/255 - 0.5) * $contrast) + 0.5) * 255;
  78    $b = ((($b/255 - 0.5) * $contrast) + 0.5) * 255;
  79  }
  80  
  81  function _imageapi_gd_pixel_colorize(&$r, &$g, &$b, &$a, $arg1, $arg2, $arg3, $arg4) {
  82    $r += $arg1;
  83    $g += $arg2;
  84    $b += $arg3;
  85  }
  86  
  87  function imagefilter(&$im, $var, $arg1 = NULL, $arg2 = NULL, $arg3 = NULL, $arg4 = NULL) {
  88  
  89    switch ($var) {
  90      case IMG_FILTER_NEGATE:
  91        _imageapi_gd_pixel_color_walk($im, '_imageapi_gd_pixel_negate');
  92        return TRUE;
  93  
  94      case IMG_FILTER_GRAYSCALE:
  95        _imageapi_gd_pixel_color_walk($im, '_imageapi_gd_pixel_grayscale');
  96        return TRUE;
  97  
  98      case IMG_FILTER_BRIGHTNESS:
  99        _imageapi_gd_pixel_color_walk($im, '_imageapi_gd_pixel_brightness', $arg1);
 100        return TRUE;
 101  
 102      case IMG_FILTER_CONTRAST:
 103        // normalize between 0-1, square to keep positive.
 104        $contrast = pow((100-$arg1)/100, 2);
 105        _imageapi_gd_pixel_color_walk($im, '_imageapi_gd_pixel_contrast', $contrast);
 106        return TRUE;
 107  
 108      case IMG_FILTER_COLORIZE:
 109        $arg1 = (is_null($arg1)) ? 0 : $arg1;
 110        $arg2 = (is_null($arg2)) ? 0 : $arg2;
 111        $arg3 = (is_null($arg3)) ? 0 : $arg3;
 112        $arg4 = (is_null($arg4)) ? 0 : $arg4;
 113        _imageapi_gd_pixel_color_walk($im, '_imageapi_gd_pixel_colorize', $arg1, $arg2, $arg3, $arg4);
 114        return TRUE;
 115  
 116      case IMG_FILTER_EDGEDETECT:
 117        return imageconvolution($im, array(array(-1, 0, -1), array(0, 4, 0), array(-1, 0, -1)), 1, 127);
 118  
 119      case IMG_FILTER_EMBOSS:
 120        return imageconvolution($im, array(array(1.5, 0, 0), array(0, 0, 0), array(0, 0, -1.5)), 1, 127);
 121  
 122      case IMG_FILTER_GAUSSIAN_BLUR:
 123        return imageconvolution($im, array(array(1, 2, 1), array(2, 4, 2), array(1, 2, 1)), 16, 0);
 124  
 125      case IMG_FILTER_SELECTIVE_BLUR:
 126        for ($y = 0; $y<$max_y; ++$y) {
 127          for ($x = 0; $x<$max_x; ++$x) {
 128            $flt_r_sum = $flt_g_sum = $flt_b_sum = 0;
 129            $cpxl = imagecolorat($im, $x, $y);
 130            for ($j=0; $j<3; ++$j) {
 131              for ($i=0; $i<3; ++$i) {
 132                if (($j == 1) && ($i == 1)) {
 133                  $flt_r[1][1] = $flt_g[1][1] = $flt_b[1][1] = 0.5;
 134                }
 135                else {
 136                  $pxl = imagecolorat($im, $x-(3>>1)+$i, $y-(3>>1)+$j);
 137                  $new_a = $pxl >> 24;
 138                  //$r = (($pxl >> 16) & 0xFF);
 139                  //$g = (($pxl >> 8) & 0xFF);
 140                  //$b = ($pxl & 0xFF);
 141                  $new_r = abs((($cpxl >> 16) & 0xFF) - (($pxl >> 16) & 0xFF));
 142                  if ($new_r != 0) {
 143                    $flt_r[$j][$i] = 1/$new_r;
 144                  }
 145                  else {
 146                    $flt_r[$j][$i] = 1;
 147                  }
 148  
 149                  $new_g = abs((($cpxl >> 8) & 0xFF) - (($pxl >> 8) & 0xFF));
 150                  if ($new_g != 0) {
 151                    $flt_g[$j][$i] = 1/$new_g;
 152                  }
 153                  else {
 154                    $flt_g[$j][$i] = 1;
 155                  }
 156  
 157                  $new_b = abs(($cpxl & 0xFF) - ($pxl & 0xFF));
 158                  if ($new_b != 0) {
 159                    $flt_b[$j][$i] = 1/$new_b;
 160                  }
 161                  else {
 162                    $flt_b[$j][$i] = 1;
 163                  }
 164                }
 165  
 166                $flt_r_sum += $flt_r[$j][$i];
 167                $flt_g_sum += $flt_g[$j][$i];
 168                $flt_b_sum += $flt_b[$j][$i];
 169              }
 170            }
 171  
 172            for ($j=0; $j<3; ++$j) {
 173              for ($i=0; $i<3; ++$i) {
 174                if ($flt_r_sum != 0) $flt_r[$j][$i] /= $flt_r_sum;
 175                if ($flt_g_sum != 0) $flt_g[$j][$i] /= $flt_g_sum;
 176                if ($flt_b_sum != 0) $flt_b[$j][$i] /= $flt_b_sum;
 177  
 178                $new_r = $new_g = $new_b = 0;
 179  
 180                for ($j=0; $j<3; ++$j) {
 181                  for ($i=0; $i<3; ++$i) {
 182                    $pxl = imagecolorat($im, $x-(3>>1)+$i, $y-(3>>1)+$j);
 183                    $new_r += (($pxl >> 16) & 0xFF) * $flt_r[$j][$i];
 184                    $new_g += (($pxl >> 8) & 0xFF) * $flt_g[$j][$i];
 185                    $new_b += ($pxl & 0xFF) * $flt_b[$j][$i];
 186                  }
 187                }
 188  
 189                $new_r = ($new_r > 255)? 255 : (($new_r < 0)? 0:$new_r);
 190                $new_g = ($new_g > 255)? 255 : (($new_g < 0)? 0:$new_g);
 191                $new_b = ($new_b > 255)? 255 : (($new_b < 0)? 0:$new_b);
 192                $new_pxl = imagecolorallocatealpha($im, (int)$new_r, (int)$new_g, (int)$new_b, $new_a);
 193                if ($new_pxl == FALSE) {
 194                  $new_pxl = imagecolorclosestalpha($im, (int)$new_r, (int)$new_g, (int)$new_b, $new_a);
 195                }
 196                imagesetpixel($im, $x, $y, $new_pxl);
 197              }
 198            }
 199          }
 200        }
 201        return TRUE;
 202  
 203      case IMG_FILTER_MEAN_REMOVAL:
 204        return imageconvolution($im, array(array(-1, -1, -1), array(-1, 9, -1), array(-1, -1, -1)), 1, 0);
 205  
 206      case IMG_FILTER_SMOOTH:
 207        return imageconvolution($im, array(array(1, 1, 1), array(1, $arg1, 1), array(1, 1, 1)), $arg1 + 8, 0);
 208    }
 209  }