PDF format

[heinrich5991]

Specification: https://opensource.adobe.com/dc-acrobat-sdk-docs/pdfstandards/PDF32000_2008.pdf
Sample: https://opensource.adobe.com/dc-acrobat-sdk-docs/pdfstandards/PDF32000_2008.pdf

[armijnhemel]

please note: PDF is typically parsed from the end of the file using an index with offsets, which is difficult with kaitai struct, as you first have to jump all the data, search for the index and then parse the file using the information from the index.

[Kreijstal]

if you want to understand pdf better use qpdf

[rillig]

It would definitely be interesting to see how far Kaitai Struct can model the PDF format, due to these specialties:

• Embedded streams that can be decoded into other file formats (TTF, PNG, JPEG)
• Multiple references to the same PDF object
• Possible gaps in the file that could be garbage-collected or used for steganography
• Circular references between PDF objects
• Textual PDF commands l, m, Tj