How to achieve the photo effect of “Live Christmas Music at the Americana in Glendale, California” by Chris Yarzab?

Question

I came across the below photo while browsing Wikimedia Commons. (Photo by Fourbyfourblazer)

My Question, how was this photo processed to obtain this effect?

HDR, Photoshop Filters, What?

Answer

I used Photoshop with Topaz Labs Denoise and Adjust.

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