I'm trying to upload a geofilter for snapchat (it's a PNG btw) and I used photoshop to make my filter, the end result was 689kb but I need it be 600kb MAX. Is there any way I can lower the storage size? ps. I have two texts that says LAGRANGE HIGH and another that says GATOR, they both are in 3D if that matters.
Jeff Attwood recently recommended looking into Zopfli as a compression tool, but also lists others, including PNGout, of which he says:
Take any random PNG of unknown provenance, apply PNGout, and you're likely to see around a 10% file size savings, possibly a lot more.
... and goes on to say that Zopfli (although slow) gives smaller files still. The link gives figures, and some of them have ratios which will meet your target.
Which lossless compression to use and how effective it is will depend a lot on your files and what compression you've been using hitherto.