Ps stovepipe can use the liquefaction tool, open a picture that needs stovepipe, then copy a layer, then liquefy it with a filter, select the shrinkage tool in the toolbar on the left, then adjust the size of the brush to cover one leg, and then pull it down from top to bottom. Shrinkage strength can adjust the shrinkage value of the brush, thus shrinking the other leg. When finished, merge the layers and save them.