Access PNG Metadata

Question

How can I access/remove PNG metadata?

I'm looking for a Mac application or a PHP snippet.

Answer 1

Take a look at Smush_it image optimizer + API.

Answer 2

Sorry to post a Windows software, but if you don't find anything good for MAC, there's TweakPNG, which is by far the best PNG disassembler I've seen.

Answer 3

PNGCrush can remove metadata as well as optimize/recompress the bitmap images.

Answer 4

exiftool is a Perl command-line application and library that has the ability to write PNG metadata. It is multi-platform, and even has an OS X installer version.

Answer 5

A search for png on iUseThis yields a long list of apps for trimming pngs.

I have ImageOptim installed, but I cannot remember if that one really was the best of them all. I did try out a few.

Answer 6

My answer to another question gives a short Python script that removes all non-critical chunks. You'll need to download PyPNG, but that's just one Python file.