Raw formats have a calculable video payload
Multiply width by height, frames per second and bits per pixel. Divide by one million for decimal Mbps. YUY2 uses 16 bits per pixel; NV12 averages 12; RGB24 uses 24. A 1280 × 720 YUY2 stream at 30 FPS is 442.368 Mbps before transport overhead. The same pixels in NV12 require 331.776 Mbps.
Compressed capture is not a fixed ratio
MJPEG and H.264 are affected by quality, scene detail, motion and encoder choices. A recording file can also use a different codec from the camera’s USB stream. Enter a peak capture bitrate from a measurement or a trustworthy device specification. Do not substitute the final streaming bitrate used by OBS for the camera’s transport bitrate.
Headroom is a chosen assumption
This calculator lets you reserve a percentage of link speed. The default is a starting point for comparison, not a standard-mandated safe threshold. Lower the budget when other devices share the path or replace it with a measured payload ceiling. A successful mathematical fit is a reason to test the setup, not proof that every USB endpoint will be scheduled.