This orchestral piece is a spectacular Variations by repeating simple harmony of two measures. It starts quietly, gradually gets excited and it ends well. Because it is 120 bpm with 4/4 time signature, 2 measures are just 4 seconds. You can easily change the length of the audio by crossfading at 4-second intervals. For example, for the short video, cut the middle part and use it. For the long video, you can use only the opening and ending, and use another audio in the middle part.