You must have seen various blogs showing you featured images having post title written over them. New Auto Featured Image from Title plugin by Chris Huff lets you do same thing in your WordPress site.
This plugin is designed to automatically generate an image using your blog post title (for a new post) and set it as the featured image i.e. post thumbnail automatically.
The image is then included in your theme, wherever the featured image for the post is called for.
Using Auto Featured Image From Title Plugin:
Start by installing and activating Auto Featured Image from Title plugin in your WordPress site.
Upon activation visit your admin area dashboard Settings -> Auto Featured Image From Title and select your options (this is optional).
Now visit your admin area dashboard Posts -> Add New page and publish a post and the plugin will automatically generate a featured image using your post title with background image.