Question

I want to create a PDF file which does not contain angle brackets in it’s source.

This apparently implies not using the dictionary data type, as this involves << and >>.

Is it possible to completely avoid angle brackets and still create a PDF file with formatted content?

Can it be done hiding in a stream, using a character encoding technique or with an alternative dictionary notation?

The solution is needed for an obfuscation technique; the bracket-problem cannot be circumvented.

Answer 1

I think this is not possible. Every element in a PDF file is contained in some dictionary: the document catalog (the root dictionary), the page objects, the page content streams, all of them are dictionaries that require the char sequence << >>.

Sample catalog dictionary:

1 0 obj
<<
/Pages 2 0 R
/Type /Catalog
>>
endobj

If you want to use a "instructions sequence only" presentation format, you may try using PostScript instead.

Edit after comments:

Using a stream object with some filter encoding will not solve your problem, since you still need to specify the filter type in the stream dictionary.

Example:

5 0 obj
<</Length 6 0 R /Filter /FlateDecode>>
stream
***illegible characters***
endobj