1. Open the PPT and create a blank presentation.
2. Insert a picture.
3. Scale the picture to the size you want to display and make a copy.
4. Cut the size of one of the pictures to 16: 9 (that is, the aspect ratio of the slide).
5. Then, scale the image size to the page size.
6. Set the big picture to blur effect.
7. Finally, set a shadow on the small picture displayed in the front to distinguish it from the background, and get the final effect.