TCPDF is an Open Source PHP class for generating PDF documents without requiring external extensions. TCPDF supports all ISO page formats and custom page formats, custom margins and units of measure, UTF-8 Unicode, RTL languages, HTML, barcodes, TrueTypeUnicode, TrueType, OpenType, Type1, and CID-0 fonts, images, graphic functions, clipping, bookmarks, JavaScript & forms.

Some Features

• Supports document encryption
• Includes graphic (geometric) and transformation methods
• Automatic page break
• Stroke and clipping mode for text
• Supports clipping masks
• Digital signatures support
• Page compression support

TCPDF is a Free Libre Open Source Software (FLOSS).

Website: http://www.tcpdf.org/

Download: http://sourceforge.net/projects/tcpdf/