Help with Gravity 2.0 display

I'm using Arduino IDE to program the display. In the example provided from DFrobot there is a program called “background”. It uses 4 images, bgscenery.png, bgcity.png, bgtechnology.png and bgscience.png. I can't find them on the drive, I checked every folder on the drive. Searched my entire hard drive for any file with a .png extention and can't find them. These images have amazing colors, clarity and detail and I want mine to look as good as these. Any help finding them is greatly appreciated.