Converted?

Hi all,

A friend sent me a vob file (supposedly mpeg2). Opened it with Powerdvd and I immediately noticed the degraded quality (compared to other files of same format). I then checked the video attributes under the configuration tab and it stated that it was an mpeg2.

Also ,(here’s the kicker), there’s a Divx watermark in the lower right hand corner.

My question. Is there any way to determine if this file was converted other than a visual analysis?

Thanks