Photoshop :: Make Lines Into Dots Of Different Sizes?

I'm trying to figure out how to create an image of a solid line into one with a dotted line. this isn't a matter of spacing, but rather filters of some sort (i'd imagine). See this example for the best explanation:

I had the first image (from a brush) and created the second by hand. I literally took a layer and traced the original with dots, making them larger or smaller as I went along. There must be a better way! So I'm looking for the way to convert a line of varying widths to a single dotted line of various-sized dots. make sense?

I'm looking for a something similar to the new orbit packaging.