Determine Bandwidth of 4k video

I know I am doing something wrong because my math does not make sense. Can someone help me explain what am I doing wrong for purposes of learning. This is my logic:

Approach 1

According to the internet 4K video is 233 MB per minute according to this link and others.

If speed is 233 MB per minute this equals

``````convert to Megabytes per second (233/60)  =  3.9 MB/s
convert to megabites per second           = 31.2 Megabits/s
``````

Approach 2

I have a 4k video on my computer that lasts 28 seconds. The size of the file is 200 MB. Using this information it means that:

``````convert to Megabytes per second (200/28) =7.14 MB/s
convert to megabits per second = 57.12 Megabits/s
``````

This means that I need an internet speed of 57 Megabits per second to download a 1 hour 4k movie in one hour?

I have a internet speed of 20 Megabits per second and a 2.x hour 4k movie on netflix downloads in less than one hour. Why is this true?

• Are you asking about raw video, or H.264 compressed video, or HEVC compressed video, etc.? – user1686 Mar 17 '20 at 18:09
• I did not know that it was compressed. I just want to understand how it works so the math works – Tono Nam Mar 17 '20 at 18:12
• Well that's kinda the whole point of compression – to make it smaller than what the math says it would be... – user1686 Mar 17 '20 at 18:13