For example, we want to animate a photo from the top left. We take the “Lasso Tool” and select the desired photo.
As soon as you select a photo, press ctrl+C to copy
If your files are of rectangular shape, see the instruction: Using Photoshop (square photos)
Press on the keyboard command+N (mac) / ctrl+N (windows) or “File” - “Create”
In the window (do not change anything, as Photoshop has put the sizes of the photo you copied) – just press “Create”
A whitespace is shown (with dimensions) of the copied photo. Press ctrl+V to embed the photo
Your photo is ready – just save it. We shall save a photo and a mask at once. For operation of the mask tool read here.
To save the photo. Press ctrl+shift+s (windows) command+shift+s (mac) to open the window for saving. Chose jpg format and name your file, for example photo1.jpg
Move to Mask saving. Click twice on the layer with the background. Chose the color overlay tool, chose the black color and press Oк.