Changing aspect ratio

[spolja]

Hi,
I don't know where to post so i'll put it here.

I have some material encoded in 4:3 format but originally was 16:9. I was wondering can I change AR without transcoding video? I want to store that video in MKV so does MKV have some flag or something that can do this?
or
Is it up to player only?

Tried with search but after 20 min's reading found nothing.:o

Thanks in advance and sorry for my bad english.

[Selur]

changing Display Apect Ratio with mkvmerge (part of mkvtoolnix) should be no problem.

[spolja]

Yes, it seems to do the trick. Thx