7  * Image processing adapter for PHP's libGD
11     /** @var resource libGD image */
12     protected $image;  variable in splitbrain\\slika\\GdAdapter
13     /** @var int width of the current image */
15     /** @var int height of the current image */
25         $this->image = $this->loadImage($imagepath);
33         // destroy the GD image resource (only needed on PHP < 8.0)
34         if (is_resource($this->image)) {
35             imagedestroy($this->image);
67         $transparency = imagecolorallocatealpha($this->image, 0, 0, 0, 127);
69         // rotate (orientation 2 is a flip-only case and keeps $this->image)
70         $image = $this->image;
72             $image = imagerotate($this->image, 180, $transparency);
74             $image = imagerotate($this->image, -90, $transparency);
77             $image = imagerotate($this->image, 90, $transparency);
83             imageflip($image, IMG_FLIP_HORIZONTAL);
86         if ($image !== $this->image) {
87             $this->__destruct(); // destroy old image
88             $this->image = $image;
93             imagealphablending($this->image, false);
94             imagesavealpha($this->image, true);
134         $saver = 'image' . $extension;
136             throw new Exception('Can not save image format ' . $extension);
140             imagejpeg($this->image, $path, $this->options['quality']);
142             $saver($this->image, $path);
149      * Initialize libGD on the given image
160             throw new Exception('Failed to read image information');
165         // what type of image is it?
169             throw new Exception('Can not work with image format ' . $this->extension);
173         $image = @$creator($path);
175         if ($image === false) {
176             throw new Exception('Failed to load image wiht libGD');
179         return $image;
183      * Creates a new blank image to which we can copy
214             $this->keepGifTransparency($this->image, $canvas);
225      * @param resource $image Original image
226      * @param resource $canvas New, empty image
229     protected function keepGifTransparency($image, $canvas)  argument
240             $transcolorindex = @imagecolortransparent($image);
241             $transcolor = @imagecolorsforindex($image, $transcolorindex);
267      * from the original image to be then resized to the wanted dimensions.
336                 $this->image,
349                 $this->image,
361         // destroy original GD image ressource and replace with new one
363         $this->image = $newimg;