Aspect Ratio & Subtitle Questions

[Alizee]

A couple of quick questions -

The other day I encoded my first 'non-anamorphic' (letterbox) widescreen dvd to Xvid using AutoGK. The results were fine except the transfer had been cropped to remove the black bars - effectively turning a 1.85:1 non-anamorphic transfer into an anamorphic one. I assume the reason for this is because the resolution settings being left on 'Auto Width' has duped AutoGK into thinking the top and bottom black bars are irrelevant space? If true, would AutoGK crop to remove the black bars of a 2.35:1 widescreen transfer as well, which would distort the image by forcing it into 1.85:1 to fill the whole screen?

Hope that makes sense.

Second question is regarding subtitles. Every time I've tried to hardcode subtitles into the transfer it simply hasn't worked - Subtitles just don't appear on screen. However, clicking the external subtitle option seems to work ok - I prefer external subtitles rather than burnt in ones so it's not too much of a problem but still confusing. I've tried converting to both xvid and divx with the same result - transfer converts as normal but no subs to be seen unless I use the external option and leave the .avi in the same dir as the .idx and .sub files. I'm afraid I don't have access to the log info as I was using a friends PC.

[Backflip]

By anamorphic do you mean the picture is now stretched during normal playback? Also, what was the resolution which was chosen? 640 x ...? 720 x ...?

With AutoGK open CTRL-F9 gives you further options to force a 16:9 (WS) encoding and choose cropping settings. That's if AutoGK is incorrectly outputing a fullscreen video (i.e. - stretched picture). You can also choose different crop settings there (tick Tune autocrop parameters>give Theshold a '0' value, then under Force cropping of input you values), but you'll need to get correct cropping settings using some other program, like GordianKnot etc.

[niann]

How are you playing the movie back? If you are using a computer to watch the XviD result, you would indeed want the black bars cropped from the picture. There is no reason to have those bars there, unless you are trying to watch the result on a hardware player. In which case the player should "add" the bars back on by itself. If I misunderstood your question please let me know. :)

Cheers!

[CWR03]

Regarding the "black bars," there may be no need for them depending on how th file is viewed, but if a standalone player is used to watch them that doesn't correctly resize the playback but instead stretches it to fill the screen top to bottom, you might want to leave it letterboxed. The black areas take almost no bitrate from the encode, and if it's necessary to leave them there should be no quality loss.

[Alizee]

I think I've confused people with my question, sorry.

The short of it is -
The dvd I encoded was widescreen. However the dvd transfer wasn't enhanced for playback on widescreen TV sets. This means that if you put the dvd into your home dvd player and play it back on a widescreen TV you will still get the same black bars at the top and bottom that you would get on a 4:3 standard TV. You have to manually zoom in the widescreen TV picture to get it to display in widescreen without black bars.

I encoded this dvd using autogk. The resulting xvid now had these black bars at the top and bottom removed. When I play the xvid back on my widescreen TV there are no longer any back bars at the top and bottom and there is no need to zoom in manually because autogk has removed them in the encoding process - Possibly a good thing, although potentially detrimental to the resulting picture quality and aspect ratio.

I'm just curious as to why this happened and why autogk seemed to crop the black bars from the transfer as though this is unneeded space. In fact on a 2.35:1 widescreen transfer for example the black bars are needed in order to maintain a correct aspect ratio.

Hope this makes more sense now. Basically if you've never had to encode a non-anamorphic dvd then it's probably difficult to understand.

[manono]

Hi-

I've encoded plenty of AVIs from 4:3 widescreen DVDs. Nasty things, those.

I encoded this dvd using autogk. The resulting xvid now had these black bars at the top and bottom removed. When I play the xvid back on my widescreen TV there are no longer any back bars at the top and bottom and there is no need to zoom in manually because autogk has removed them in the encoding process - Possibly a good thing, although potentially detrimental to the resulting picture quality and aspect ratio.

AutoGK by default will remove the black bars. It's standard practice for AVI encoding. As you mentioned, when playing a 4:3 widescreen DVD, zooming it to fill the screen of a widescreen TV set may make it look lousy, as there's just not enough resolution in the DVD to begin with. Reencoding for AVI might also make it look pretty bad, as a DVD/MPEG-4 player will scale it to fill the screen left to right. As mentioned, if you would prefer that it play with black bars on all 4 sides on your widescreen TV set, then go into the hidden options and make sure it doesn't crop the black bars.

I'm just curious as to why this happened and why autogk seemed to crop the black bars from the transfer as though this is unneeded space. In fact on a 2.35:1 widescreen transfer for example the black bars are needed in order to maintain a correct aspect ratio.

It is unneeded space. Yes, a 16:9 2.35:1 DVD has black bars already in it. A 4:3 2.35:1 DVD has even more black bars. If the resulting AVI without black bars gets stretched vertically to fill the widescreen TV, and everyone looks too tall and skinny, then you have a crummy player that doesn't scale correctly (DVP-642 perhaps?). The player itself should be adding black bars for output with the correct aspect ratio. Again, you'll have to tell AutoGK to leave the black bars in there.

[CWR03]

Probably the easiest solution would be to uncheck the Auto Crop under the advanced settings. This should leave you with a proper aspect ratio, properly letterboxed video.

[manono]

Oh, you don't have to go into the Hidden Options any more to disable the Auto Crop? Maybe it's time I updated my AutoGK. Thanks CWR03.

[CWR03]

Sorry, I haven't used AutoGK in some time and forgot it's called "Hidden Options" and not "advanced settings." Either way, disabling auto-crop can solve a lot of compatibility issues.