CGPDF vs iBooks features PDF rendering

Question

I am making a PDF reader and it works very well with most PDF files. During testing with a bunch of different documents (on the iPad), I found one that crashes the application - it uses vector graphics and images heavily, so I'm not surprised. I also bought a bunch of PDF readers (primarily Good Reader and ReaddleDocs) to test them with this document, and they all freeze for three or four seconds and then crash.

Now the problem: I just tried it on iBooks and it works flawlessly. How is this possible? Maybe Apple does not use the CGPDF feature set, like all other applications? Or maybe there is something that I don’t know, for example, some open-source PDF rendering library that can be used instead? (I could not find them).

Update:. I finished re-exporting the PDF file and now it works great, but I still would like to know why iBooks does a great job with the old one. :)

Answer 1

It is possible that the PDF was damaged, a good reader has a function (in the last upadate) to fix damaged pdf files, maybe ibooks did it automatically