Sometimes I will select a piece from an image, put the fragment on its own transparent layer, and duplicate that layer into a different document. I then need to resize--and, in some cases, enlarge--that fragment to its purpose in the new image. When enlarging, my practice has been to export the fragment as a .tif, enlarge it in Photozoom, then bring it back into the new Photoshop document. (The point of Photozoom is to maintain image quality by resampling rather than by just stretching the image.) I'm thinking there must be an easier way to resize/resample a selection (not an image or a layer but a selection). Any thoughts?
What stretching an image is transforming an layer or resizing an image document. It is done by resampling the layer or image document. How well the resampling is done depends on the interpolation method used, the contents of the image and the quality of the images pixels you have to begin with. After the resampling you have a new image not a single original pixel remain unless the layer being resample is a smart object layer. The smart object layer pixels are locked and not altered just the layer transformed appearance is. Any time you transform a smart object layer the smart object layers pixels are transform for the layers composite view. You can specify which interpolation method to use.
JJ, thanks very much.