[Tex/LaTex] How to make pdfcrop output all pages of the same size

pdfpdfcroppowerpointpresentations

I am trying to crop a powerpoint animation that I converted to pdf for import into beamer (using ppsplit), but when I run pdfcrop (from texlive) to reduce the whitespace, it crops the pages individually such that each page is a different size. Is there a way to make it so all pages are the same size as the largest page?

I found that the --verbose flag will output the bounding box used at each step. Since this was a "growing" animation, the last page is the largest.
%%HiResBoundingBox: 48.000022 299.872046 624.124950 420.127932

pdfcrop --bbox "48.000022 299.872046 624.124950 420.127932" ~/animation.pdf