Proper method to extract the hash from a PDF file?

[marTi]

Hi, I found this thread cause I look for an easy way to determine which mode to choose, and how to determine this easy way which pdf is encrypted by which method. As an example, I have bunch of encrypted pdf's:

Code:

$pdf$1*2*40*-4*1*16*
$pdf$1*2*40*-64*1*16*
$pdf$2*3*128*-1028*1*16*
$pdf$2*3*128*-3904*1*16*
$pdf$2*3*128*-4*1*16*
$pdf$4*4*128*-1028*1*16*
$pdf$4*4*128*-4*1*16*
$pdf$5*5*256*-1028*1*16*
$pdf$5*6*256*-1028*1*16*

is it enough to determine the mode, or maybe hash length is also important? Maybe it would be easier to implement this into hashcat to autoguess mode from given hash. Thanks in advance for help