On many videos, say of an interrogation or raw video from a television show, there’s a counter. They seem to be of the form HH:MM:SS:?? and my question is what do the ?? stand for? It’s confusing because they seem to only go from :00 to :30 (or rather, :29 with :00 standing for :30), and the seconds increase by one with each cycle. That is, they seem to be dividing seconds up into 30 parts. Why?
The old television broadcast standard = 30 frames per second.
(Which is shorthand. It’s technically measured at 29.97, and it’s also actually double that, because it’s half-frames interlaced. But that’s the number at the end of the counter.)
Frame rates…duh. Thank you.
[annoying pedant mode]
The counter is counting frames. The rate at which frames happen AKA the “frame rate” is ~30/sec.
[/annoying pedant mode]
And it’s not at all unusual to see other common frame rates in these displays, including 25 FPS (PAL), 24 FPS (film), and 15/10 FPS (surveillance video).