How to Use Content Aware Scaling in Photoshop CC (2018) - Class 2
Although the exact way the algorithm works is technically complex, don’t worry. It’s pretty darn simple to use. Here’s how to apply content-aware scaling:
Step 1:
Choose your desired layer in the Layers panel. If you want to isolate the scaling to a selection on the layer, make that selection now.
Content-aware scaling doesn’t work on adjustment layers, layer masks, individual channels or Smart Objects. If you’re scaling a Background layer, choose Select→All.
Step 2:
Choose Edit→Content-Aware Scale.