Likely a high-definition (HD) performance clip, a "bubble" (private message app) video leak, or an Instagram story archive.

If you are looking for the technical "report" of the file's properties, it generally falls within these parameters for K-pop media:

.mp4 (MPEG-4 Part 14), a universal container format compatible with almost all media players and social platforms. Common Origin:

1080p (1920x1080) or 4K (3840x2160) for modern fancams.