Working with low-level PDF APIs can enable a wide variety of customizations with PDF documents.

Apryse SDK offers the following benefits:

• Full access to low-level PDF object model (also known as COS/SDF)
• Seamless integration between high and low-level API
• Functionality not available in the high-level API can be implemented using COS/SDF API

Adding custom information
To add custom information to an existing document.

A short introduction to PDF file format
An introduction to PDF file format.

SDF / COS object model
An introduction to SDF objects.

Filters and streams
An introduction to filters and streams.

Embedded Fonts
An introduction to embedded fonts.

PDF CosEdit
A windows GUI tool for low-level PDF editing to view, add, or edit information for an existing document.