“If you’ve ever been perplexed by the small photographs used to represent YouTube clips, you’re not alone,” writes Tampa Tribune staffer Gregg Williams. The reason is that “the photos are selected automatically, with no regard to its actual content: It’s the frame that falls precisely in the middle of the clip. From a promotional standpoint, these ‘middle frame’ images are hit-or-miss. As the basis for a pop-culture quiz, on the other hand…”