How to calculate bitrate not through file size?

[VietDuc19]

Hi everyone!
As far as I know, Bitrate is a measurement of the number of bits that are transmitted over a set length of time and it can be calculated by:

File size = bitrate (kilobits per second) x duration (second)

Now, I am looking into a question: when i encode video by 2pass with video codec x264, how to calculate bitrate of video if I do not know File size but i know duration, resolution and framerate of video????
Thank you for all your help! :thanks:

[Guest]

You cannot calculate the bitrate with only that information, unless it is uncompressed or you know the compression ratio.

[VietDuc19]

You cannot calculate the bitrate with only that information, unless it is uncompressed or you know the compression ratio.

Thank you for your answer, my friend!