There are times when you don’t want to show all of a particular image or video as a layer. You can delete portions of a media layer using the Cropping tool. This masks part of the media layer.
To use the Cropping tool, tap on the media (image or video) layer that you want to mask, then tap the Cropping button in the Options Panel that opens up on the right side of the screen.
Tap the Enable Mask button to activate the Cropping tool. Next, choose a mask preset shape. Custom mask shapes are not currently available in KineMaster.
Use the Feather slider to soften the edges of your mask. This helps to blend in your media layer to other elements in the Primary Timeline or layers below the masked media layer.