Why is 24fps labeled as NTSC in settings? Shouldn't that be 29.97?

[Kizzume]

Also, why is there no 23.98 as a common FPS value? One has to set a fractional fps of 24000/1001.

 

[Suslik V]

UI: Add 24 NTSC as a common FPS value · obsproject/obs-studio@52784c3

OBS Studio - Free and open source software for live streaming and screen recording - UI: Add 24 NTSC as a common FPS value · obsproject/obs-studio@52784c3

github.com

Internally, the "24 NTSC" entry sets framerate numerator = 24000 and denominator = 1001.
The "29.97" entry sets framerate numerator = 30000 and denominator = 1001.

You may find in OBS other fractional values with next meaning:
"119.88 NTSC" = 120000, 1001;
"59.94 NTSC" = 60000 / 1001;
"48 film" = 48000 / 1001;
"29.97 NTSC" = 30000 / 1001;
"24 film" = 24000 / 1001.
( source: https://github.com/obsproject/obs-s...c/plugins/win-dshow/win-dshow.cpp#L1255-L1278 )

General rule was "integer number, no additional text" ---> denominator = 1. The rule was broken in:

UI: Add PAL 25 & 50 FPS as common FPS values · obsproject/obs-studio@7c0620b

OBS Studio - Free and open source software for live streaming and screen recording - UI: Add PAL 25 & 50 FPS as common FPS values · obsproject/obs-studio@7c0620b

github.com

because 25 fps and 50 fps originally wasn't listed in OBS and added later by different author.

 

[Kizzume]

Interesting. Thanks for that. My main question still remains though: Why is 24fps being associated with NTSC? It makes no sense. 24fps is the cinematic standard. If it said "24 Cinema" it would make far more sense than labeling it as NTSC.

NTSC was the analog broadcast standard for interlace television, which could either be considered 29.97 full frames a second, or 59.94 half frames a second.

 

[Suslik V]

In my opinion common values should include only integer numbers, anything else has no sense at all.