如何使用iTextSharp调整pdf的大小

I have a bunch of PDFs that I'm just trying to open, resize the page, and then save. I'm also hoping that the file sizes will shrink significantly doing so. I am using iTextSharp and the resizing works just fine, but the file size is nearly identical, ever so slightly larger in fact. Here's the function I have now:I have a bunch of PDFs that I'm just trying to