Why does the Airplay icon fail to appear in some QuickTime videos in the QuickTime Player?
I recently took 4 drone videos and within the QuickTime Player, exported each to 480p, 720p, and 1080p H.264 MP4s from the 4K MP4 source.
When I opened them up last week on my 32GB M2 Max MBP 16, only one of the videos showed the Airplay icon in the QuickTime Player. My goal was to airplay them to my AppleTV that I'd brought with me 8400 miles to Africa.
Today, I'm 8400 miles away from that AppleTV and I open up all of the videos on the same MBP but the Airplay icon appears in the scrubber overlay for all of the videos in QuickTime.
Why?
What are the criteria that determine if a video can be airplayed within the QuickTime Player or not? There's no information that I can find on the Apple support site. Nothing that will tell you what is required for a video to support Airplay.
Why would the "airplayness" of a video change when opened on the same device?
What are the criteria that enable a video to be airplayed?