Determining duration (or frame count) of APNG

Question

Any way to count APNG frames in JS, in the browser?

For a script that tinkers iteration count and interactivity, I'd like to determine from a given APNG file how long a single iteration of its animation takes. I assume that's not explicitly written anywhere, but perhaps frames * (1 / 72) could do the trick.

Answer 1

The logic is more complicated than I thought, but anyway it seems like apng-js has figured it out - It parses APNGs correctly, along with frames, play time and more.