@dacara, @jdevinone, There may be some apps that will do that but here's how I do it.
First I copy your picture and drop it into Powerpoint. Once I do that I take the area that I want to recolor and using the Freeform drawing tool to draw a polygon around that area. After it's drawn I pick the color and the transparency level and recolor the picture. When you're finished with that you go to Save As and name the file and save it as a JPEG instead of a presentation. After that all you have to do is download it to the Houzz post. Sound hard but it is pretty easy.
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