I've thousands of png files which I like to make smaller with pngcrush. I've a simple find .. -exec job, but it's sequential. My machine has quite some resources and I'd make this in parallel.
The operation to be performed on every png is:
pngcrush input output && mv output input
Ideally I can specify the maximum number of parallel operations.
Is there a way to do this with bash and/or other shell helpers? I'm Ubuntu or Debian.