Linearization
PDF Linearization
Linearization (also called “fast web view” or “optimized for web”) arranges a PDF file so that the first page can be displayed while the remainder of the file is still downloading. This is specified in ISO 32000-1:2008, Annex F.
A linearized PDF has a specific structure: the linearization dictionary, the first page object, and the cross-reference stream all appear near the beginning of the file.
Checking Linearization
The Document class exposes linearization status through the document’s trailer
and cross-reference data accessible via getTrailer().
Use Cases
Linearized PDFs are beneficial for:
- Documents hosted on the web where page-by-page delivery improves perceived performance
- Large documents where only the first page is typically needed immediately
- Document delivery systems where bandwidth is constrained