I believe it was done with batting, a staple gun, and fabric. There is probably also a curved piece of foam under the batting on each row. A different fabric appears at each end as an accent.

@Carolyn Albert-Kincl Design What kind of batting would you recommend? Can this work with a stone (cinder block) wall?

For a cinder block wall you would probably want to install some wood strips to the cinder block to minimize damage to the wall. For the smooth puffiness you will need to affix the material with staples very close together which would damage the wall too much. You can take a piece of plywood the size of the wall and do the upholstery on the plywood and then affix the wood to the wall. A screw in each corner should be enough and would mean much less damage to the wall should you wish to update in the future. Have fun.

Hi melerey ....
There is a excellent use of a foam with a good interior design and i think batting is mainly used for wall hangings as i know but in future want to give you more help regarding this. I also found a site http://www.gharbuilder.com/interior-designers-decorators.php that contain more interior design ideas its my pleasure if you find it useful please try it in future. All the best friends.

Thank you for all the help!