CamVerce Studio: Object Editing: Inserting an external image file
If you want to add an image file, you can either click Picture button from Toolbar or select Picture from Insert menu > Advanced Objects.
From this Open window, select the image file and click Open. You can also see the preview of the file you selected.
Now the selected image file is added to the video. Just like objects, you have 8 handles around it. You can resize the image with these handles.
You can change the length of the image file just like any other object. Please see "Changing the length of an object using slide window" to learn how to change the length of objects.