original_string: function opacity($opacity) {
          // Determine opacity
          $opacity = $this->keep_within($opacity, 0, 1) * 100;
          // Make a copy of the image
          $copy = imagecreatetruecolor($this->width, $this->height);
          imagealphablending($copy, false);
          imagesavealpha($copy, true);
          imagecopy($copy, $this->image, 0, 0, 0, 0, $this->width, $this->height);
          // Create transparent layer
          $this->create($this->width, $this->height, array(0, 0, 0, 127));
          // Merge with specified opacity
          $this->imagecopymerge_alpha($this->image, $copy, 0, 0, 0, 0, $this->width, $this->height, $opacity);
          imagedestroy($copy);
          return $this;
      }
code: function opacity($opacity) {
          // Determine opacity
          $opacity = $this->keep_within($opacity, 0, 1) * 100;
          // Make a copy of the image
          $copy = imagecreatetruecolor($this->width, $this->height);
          imagealphablending($copy, false);
          imagesavealpha($copy, true);
          imagecopy($copy, $this->image, 0, 0, 0, 0, $this->width, $this->height);
          // Create transparent layer
          $this->create($this->width, $this->height, array(0, 0, 0, 127));
          // Merge with specified opacity
          $this->imagecopymerge_alpha($this->image, $copy, 0, 0, 0, 0, $this->width, $this->height, $opacity);
          imagedestroy($copy);
          return $this;
      }
code_tokens: function opacity ( $ opacity ) { // Determine opacity $ opacity = $ this -> keep_within ( $ opacity , 0 , 1 ) * 100 ; // Make a copy of the image $ copy = imagecreatetruecolor ( $ this -> width , $ this -> height ) ; imagealphablending ( $ copy , false ) ; imagesavealpha ( $ copy , true ) ; imagecopy ( $ copy , $ this -> image , 0 , 0 , 0 , 0 , $ this -> width , $ this -> height ) ; // Create transparent layer $ this -> create ( $ this -> width , $ this -> height , array ( 0 , 0 , 0 , 127 ) ) ; // Merge with specified opacity $ this -> imagecopymerge_alpha ( $ this -> image , $ copy , 0 , 0 , 0 , 0 , $ this -> width , $ this -> height , $ opacity ) ; imagedestroy ( $ copy ) ; return $ this ; }
docstring: Changes the opacity level of the image
  
  @param float|int     $opacity    0-1
  
  @throws Exception
docstring_tokens: Changes the opacity level of the image