And as you can’t have interlaced UHD some UHD content is double framerate. 50P here in the UK for sport.
So 8 times the content.
That’s why H265 is more suitable. Half the file size for the same quality.
But the maths don’t quite work as a linear expiration for H264. You will find the codec becomes more efficient as the data rate goes up.
I’d experiment and then add 10% to what seems artefact free.
Pat Horridge
Broadcast & Post Consultant, Trainer, Avid Certified Instructor
Free online Tutorials at VET digital media academy online https://vimeo.com/channels/752951
pat@vet.co.uk