MP4 container smaller than MKV?

[JamesWade]

I've been using MeGUI to encode all my videos and today I encoded a video with the mkv container then using the exact same video with the exact same encoding settings I encoded into the MP4 container and it comes out about 28 MB less than the MKV. Anyone know why it's smaller?

[poisondeathray]

Something is wrong, unless the video is large. The margin of difference is much less than 0.1 - 0.2%

Did you account for audio or other streams? Same processing steps ? What does the log file say ? What does mediainfo say about the 2 versions (view=>text)

[poisondeathray]

BTW I'm curious why you would do this in the first place ? (encode the same source using the same settings, just different container)

You could have just re-muxed into different container (no quality loss, many times faster) - doing this you can also prove to yourself that the filesize will be very similar

[jagabo]

the MP4 container and it comes out about 28 MB less than the MKV.

On what? A 29 MB file? A 20 GB file? Saying "28 MB less" is pretty meaningless without context.

[El Heggunte]

ASSUMING "nothing has gone wrong" in the muxing processes themselves, it's possible that the (apparent) problem was caused by the settings in the Matroska muxer. When you define the so-called "cues" for ALL audio/video frames, the container overhead gets significantly bigger.