File size differs from data size--HUH?!

[atoledo123]

So I took an mkv file and converted it with AVItools to an avi in order to play on my xbox360. The original file was h.264 video/ac3 5.1 audio. I converted to mp4video/ac3 5.1 audio in an avi container. File size reads 4.11 GB. Total data size when checked with MediaInfo is 3.83 GB. Where did the extra 0.28 GB come from? Could the file be corrupt? Is there an easy fix? Converting again I'm afraid will yield the same result.

[Case]

3.83 GiB ≈ 3.83 * (1024^3) bytes = 4,112,431,186 bytes ≈ 4.11 GB (ISO)
It is the same, just represented with a different base: 1000 (10^3) bytes in a kilobyte (ISO "base 10") or 1024 (2^10) bytes in a kilobyte (traditional "base 2").
Note that Mac OS just recently (10.6) switched from base 2 to base 10 in how the Finder shows file sizes. Individual apps can differ from that.

See also Wikipedia - Gigabyte consumer confusion
and Apple Support Article TS2419.

[atoledo123]

Thanks for the clarification.