Needing Help With Changing Aspect Ratios

[theTREE]

I have recently been encoding movies in DivX with AutoGK. This usually goes off without a hitch but I have come across a few movies with the same issue, this being that at some point during playback the aspect ratio of the video changes leaving black bars to fill the gaps throughout the rest of the film.

So, I guess my question is how can I correct this? I have some ideas, but I do not know if if any of them are possible or how I would go about it if they were. For instance, is the IFO file telling AutoGK that the aspect ratio is different in these parts and perhaps I can somehow write in different instructions? Or perhaps I can somehow isolate which VOB's (or it's cells) are at a different resolution and then somehow encode those parts seperately and splice them in place with VirtualDub? I know I would prefer not to isolate those parts after encoding and then re-encode them with a cropping filter as that always leads to lower quality video and that is the last thing I would want.

To illustrate this problem I have attached some screenshots taken from one of the movies. These are taken from different parts in the same encode.

Any help would be appreciated. TYIA

[nixo]

Unfortunately, you can't join parts with different resolutions... you'll have to overcrop in one part of the movie or leave black bars in another.

--
Nikolaj

[manono]

And AutoGK isn't the best program to use for such a project. Your best bet is to create your own AviSynth scripts for encoding manually in VDubMod, or perhaps with the help of GKnot.

You would use the Trim command to isolate the different sections where the AR changes. If you want to get rid of all the black, while it's not necessary to overcrop the sections with less black, when resizing some sections will have a greater AR error than others. I don't know if that made much sense.

As an example, say there are 2 parts to the movie, one like your first pic and the second like your second pic, with the switch taking place at frame 10000. The Trim, Crop, and Resize commands might go like this:

A=Trim(0,9999).Crop(12,0,-12,0).LanczosResize(624,352)
B=Trim(10000,0).LanczosResize(624,352)
A+B

[theTREE]

Thank You for the reply. I have never written an AviSynth script so I am not sure what you are referring to but I will do some research and give it a try in the near future.

[theTREE]

Recently I have finally found the time for new efforts in resolving the aspect ratio error problem. I have been successful in creating segments of the first film that have the correct aspect ratios, however I have run into a new, less severe, snag. The segments are of the same resolution, made using the same audio track and were created with the same codec and encoding settings excepting only the crop and resize filters. The segments were then cut at keyframes and then joined in vDubMod. That being said when I play back the new, joined file using mplayer2 (Windows Media Player 6.4) or Windows Media Player 10 I get an audio error at the joins. When the players get to these joins the audio 'pops' then, although video playback continues, audio playback ceases but if I move the slider the audio immediately resumes. Also playing the same video in another player, such as VLC, I get no error at the joins.

Since this is a different issue I am not sure if I should post this new issue in this thread or should start a new thead.

Any help with determining the cause and/or solutions to this error would be greatly appreciated.
TYIA

[manono]

I don't know why you encoded it in sections, broke it into pieces, and then joined it up again, but why can't you take the original audio and add it in to your joined up video, replacing the audio that pops?