original_string: final public function imagePNG($filename = null, $quality = -1, $filters = PNG_NO_FILTER)
  	{
  		return imagepng($this->_image_handle, $filename, $quality, $filters);
  	}
code: final public function imagePNG($filename = null, $quality = -1, $filters = PNG_NO_FILTER)
  	{
  		return imagepng($this->_image_handle, $filename, $quality, $filters);
  	}
code_tokens: final public function imagePNG ( $ filename = null , $ quality = - 1 , $ filters = PNG_NO_FILTER ) { return imagepng ( $ this -> _image_handle , $ filename , $ quality , $ filters ) ; }
docstring: Output a PNG image to either the browser or a file
  
  @param string  $filename The path to save the file to. null outputs directly
  @param int     $quality  Compression level: from 0 (no compression) to 9.
  @param int     $filters  Any combination of the PNG_FILTER_XXX constants.
  @return bool             True on success, false on failure
docstring_tokens: Output a PNG image to either the browser or a file