--pdfaes256

The --pdfaes256 option turns on the encryption for a PDF file using AES 256-bit encryption.

To specify the user and owner passwords, permissions, etc. use the --pdfuserpass, --pdfownerpass, and --pdfpermit options in conjunction with --pdfaes256.

Default Setting:

No encryption is done if no other encryption options are specified (--pdfownerpass --pdfuserpass, --pdf128, --pdfpermit, --pdfaes128, --pdfaes256). If both --pdfaes128 and --pdfaes256 are specfied, --pdfaes256 is used.