Why does the final size overcome the estimated size?

[malroux]

Hello!

When I convert a file, the estimated final size of the videofile is around 80MB for example, but the result is _always_ three or four times bigger. So, in this case the final size always end up around 280MB.

I´ve tried various profiles and settings but it always become this big. What am I doin so wrong?

(Sorry for my english, I hope you understand the imporant stuff)

Thanks.

[Nafcom]

I have never seen any of those calculators to be correct, don't know why. A typical move has around 700 MB in MP4 format

[Midiman]

I have never seen any of those calculators to be correct, don't know why. A typical move has around 700 MB in MP4 format


That's simply incorrect. The size of the file depends exclusively on the length of the movie and the bitrate that is used to encode it. Higher bitrates mean bigger files for the same length movie. The same length movie will end up the same size provided the same bitrate is used regardless of the resolution of the input or output files.

Various factors come into play when the program tries to estimate the final size of a movie. Most commonly there is an error reading the length of the source file. Without that critical piece of information, no estimate can possibly be accurate.