Comparing two 1080p BD 23.98fps copies of a film here:
http://bakabt.me/155762- UTW's is 13.4GB with vid at ~16,600 Kbps
http://bakabt.me/166976- E-D's is 6.7GB with vid at 6331 kBit/s
I got confused at first since E-D had english audio yet was half the size, but eventually the only variable with a major difference to account for it was I think the bitrate of the video.
I don't really understand what bitrate is though. I think of video as a series of frames, so I figure if both are playing the same number of frames, and the frames are the same dimensions, that they should be the same size.
I guess I'm missing on something here, what accounts for the 2x bitrate and stuff. Does it have something to do with compression? Is the video altered in the smaller E-D release to cut corners and duplicate colors in a way that allows easier compression encoding or something like that?
Wondering if someone could give a cliff's notes on how to understand this bitrate issue or direct me to some good literature about it. Read https://en.wikipedia.org/wiki/Bit_rate but still confused.
On a somewhat related note, do you find the difference worth the doubled data? Or more broadly, is 1080p worth it over 720p? Are all our eyes educated enough for it to matter when watching it realtime? We can process the difference in a screenshot but I'm not sure if we process it at the rate they go by.