Struggling with Go Concurrency Patterns

I am trying to understand: http://blog.golang.org/pipelines/bounded.go

This is from: http://blog.golang.org/pipelines

I am putting into my own test project here: https://github.com/kaihendry/makemego

Which aims to efficiently resize a bunch of images...

Even the parallel example seems a bit complex. Does it really need the waitgroup? http://s.natalian.org/2015-07-12/1436702788_1918x1058.png Can't we assume we are done once the channel is consumed??

Further burning questions: If I break with ctrl+c whilst it's working, why isn't there an error bubbling up?

How can I better visualize/debug what is happening with the queue aka channel?

Don't quite understand the go func in walkFiles... couldn't that be a LOT simpler? ... https://www.youtube.com/watch?v=DrASaA-1NDw