1. A method for outputting an alert indicating a functional state of a back-up video-broadcast system, the method comprising: receiving, by a computing device, a first video-stream that represents first video-content; generating, by the computing device, a first signature based, at least in part, upon an extent of scene-change transitions included within the first video-content; receiving, by the computing device, a second video-stream that represents second video-content; generating, by the computing device, a second signature based, at least in part, upon an extent of scene-change transitions included within the second video-content; making, by the computing device, a determination that the generated first-signature and the generated second-signature lack a threshold extent of similarity; and responsive to the determination that the generated first-signature and the generated second-signature lack the threshold extent of similarity, outputting, by the computing device, an alert.