Good extension but error when convert

Hello ,

I try to install your extension could you telle me which version you have of im and gs .

mine are im 6.4.3 and gs 7.07 : is it enough? because there is no image generation....

by the way, in your doc , there is 3 parameters :

#### Usage ####

pathtofile|pdfpreview( width [, page [, name ] ] ] )

and in your code there are 4 parameters

return array( 'pdfpreview' => array(
'width' => array( 'type' => 'integer', 'required' => true, 'default' => 99 ),
'height' => array( 'type' => 'integer', 'required' => true, 'default' => 0 ),
'page' => array( 'type' => 'integer', 'required' => false, 'default' => 1 ),
'original_filename' => array( 'type' => 'string', 'required' => false, 'default' => ''
)