How to use w3c test suite?

I wrote a script which tests several rasterization programs, by using the official w3c test suite and comparing the rasterized png with the expected pngs pixel by pixel.

The problem is, with v. 1.1 first edition (2011) and v. tiny 1.2 (2008) test suites, in a lot of images the vectors doesn't match with the expected png, because the revision number is not the same, making a lot of false-positives (more than 90%), like this one.

However it's ok with the v. 1.1 first edition test suite.

I could trunk the png to remove the area with the revision number, but it's a really derpy solution.

So by which png should I compare the rasterized vectors ?

Thanks.