Joining video files, fine tuning gets annoying

[Anonymous4442]

Often when I join two video files, the transition from the first to the second video is not perfectly smooth, meaning there is a small part that repeats itsself (because the original split was not done without excess material).

Is there some assistance that I can use to ease the fine tuning work? Currently I have to delete frames one by one and see if it fits perfectly, and do this very carefully multiple times to exclude human error. I'm using all the usual free tools available, but I am a beginner for sure.

Thanks

[Baldrick]

Avoid joining at all cost.

But what do you use to join now? Avidemux? Virualdub?
What is your source video? video codec and container.

[Anonymous4442]

I'm flexible on the tools, I have Avidemux and Virtualdub, but i'd certainly install and learn more if neccessary.

Following information is from MediaInfo application:

Containers are normally AVI. Video codec is normally mpeg-4 visual (XVID), and audio ac-3 and mp3

btw, why avoid joining at all costs? I'd really like to do it for several reasons (and be it just to learn how to do it the best way

[Baldrick]

Because joining often cause problems as you describe. No software will help you with that. You have to manually check and fine tune.

[Bjs]

Joining is less problematic where the material match's the same specs ... if there are differences most programs tend to choke and these issues turn up.

Following information is from MediaInfo application:

And ?

There is no further info attached to your post about either file involved so you'll be guessing as to the cause behind the issue.