1. A method for outputting an alert indicating a functional state of a video broadcast system, the method comprising: receiving, by a computing device, a first video-stream that represents first video-content, wherein the first video-stream was generated by a primary video-broadcast system; 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, wherein the generated first signature represents a first transition that has a first type and that is associated with a first time; receiving, by the computing device, a second video-stream that represents second video-content, wherein the second video-stream was generated by a back-up video-broadcast system; 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, wherein making the determination that the generated first signature and the generated second signature lack the threshold extent of similarity comprises determining that the generated second signature does not represent a second transition that (i) has the first type and (ii) is associated with a time that is within a tolerance period of the first time; 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 indicating that the back-up video-broadcast system is not functioning properly.