Hello, I've been trying to digitally sign PDFs generated with the mPDF library , I can successfully generate the PDF and sign it with the pdfsign.php example, but when I check the document with different programs (one of them being Adove Reader) I get a "Signature not valid, Contents illegal data". I've checked the signature itself, using a program to sign a document with it and works correctly.
Not signed PDF
Example of signed PDF
Thanks in advance.