I see that 3DGuy offered some insightful information by saying,

It also depends on what codec you're going to use and what resolution
you're going to shoot at

... along with some good comparisons and explanations about DVD encoding. 

I'm sorry that I failed to explicitly state some of my assumptions. 

I was trying to estimate the recording data rate that would be needed for
images that are about 4 mega pixels each.  In my experience, that would
be a jpeg file that is about 1 MBy to 1.5 MBy. 

What is the pixel count for standard (non HD) video images?  What is it
for HD images? 

Thanks for any additional comments.

--
Martin