: Likely the beginning of DDP5.1 (Dolby Digital Plus 5.1 surround sound).

: The file was downloaded directly from a streaming service (lossless quality) rather than recorded/re-encoded. x264 : The video codec used to compress the file (H.264).

: Contains multiple audio tracks (usually different languages). 1080p : The video resolution (Full High Definition). NF : The original source is Netflix .