php - add watermark in CI -

i want add watermark on new uploded images. using ci.

public function watermark(){         $this->load->library('image_lib');         $config['source_image'] = 'uploads/gallery/d7315a9a3039541431ab8a41820b6f00.jpg';         $config['wm_text'] = 'copyright 2015';         $config['wm_type']          = 'text';         $config['wm_font_size']     = 16;         $config['wm_font_color']    = 'ffffff';         $config['wm_vrt_alignment'] = 'middle';         $config['wm_hor_alignment'] = 'right';         $config['wm_padding']       = '20';         $this->image_lib->initialize($config);         if (!$this->image_lib->watermark()) {             echo $this->image_lib->display_errors();         }else{             echo "image created";         }     } 

it's not displaying error image not created.

try this

public function image_watermark()//change class name {     $this->load->library('image_lib');      $config['source_image'] = 'uploads/gallery/d7315a9a3039541431ab8a41820b6f00.jpg';     $config['wm_text'] = 'copyright 2015';     $config['wm_type']          = 'text';     $config['wm_font_size']     = 16;     $config['wm_font_color']    = 'ffffff';     $config['wm_vrt_alignment'] = 'middle';     $config['wm_hor_alignment'] = 'right';     $config['wm_padding']       = '5';//less padding      $this->image_lib->initialize($config);      if (!$this->image_lib->watermark()) {         echo $this->image_lib->display_errors();     }else{         echo "image created";     } }