Video Memory Requirements

Full HD

• Full HD is 2.1 Megapixel - [1]
• 1 Gig card stores 1000 pictures, or 30 minutes at Full HD 30 fps
• Standard cheapo 32G cards - 16 hours.
• One full day of storage is 43Gig.
• Cheapo USB sticks are $3/32 Gig - [2]
• $10 from China for 256 gig - [3]

Completely Depends on Compression and Bitrate

4k 60 fps:

• https://www.quora.com/How-much-storage-space-does-4k-video-at-60fps-use
• From about 3MB/sec to nearly 1 MB/sec.

One picture at 4k - also depends:

• https://linustechtips.com/main/topic/603314-how-much-space-does-one-4k-picture-take/

Conversion

• VLC converts from 4k to full HD - [4]