I need someone to modify TCPDF outputs - TCPDF is a FLOSS PHP class

General information for the website: I need modifications to TCPDF (PHP class for generating PDF documents)
Kind of development: Customization of existing website
Description of every page/module: Generated TCPDF (PDF) file should be encrypted and have a watermark. Both capabilities are inherent to TCPDF according to

1. Encryption example: http://www.tcpdf.org/examples/example_016.phps
2. PNG image example: http://www.tcpdf.org/examples/example_042.phps

TCPDF is a FLOSS PHP class for generating PDF documents.
Description of requirements/features: 1. TCPDF was used to generate "member card" style PDF's from a MySQL database.

2. TCPDF supports encryption to the created PDF files, I want the created PDF to be encrypted using the TCPDF modules.

3. TCPDF support images and watermarks. I have created an image background as a PNG file that I want on the PDF.

TCPDF is installed on the site and functioning, I am just looking to add the encryption and the watermark to the generated PDF file.
Extra notes: