VDub help? Anyone?

[permetaform]

I have a vid that's 16:9.

It keeps outputting at 4:3.

Anyone know what gives?

[]

Happy Birthday laqueta_tqo and takai_dragon! May technical difficulties be either non-existant, or always directly porportional to the amount of success you recieve in return!

Comments

[tanacawyr.livejournal.com]

What codec are you putting on it? Maybe it's one that requires a 4:3 aspect ratio, and it's forcing it if it doesn't have it ...

[permetaform]

Divx

[absolutedestiny.livejournal.com]

Well vdub will output whatever resolution you input unless you do a resize.

If the source footage is anamorphic then you will likely have to use a resize filter to scale to a 16:9 ratio such as 320x176, 400x214, 512x288, 640x352 etc. Use a high quality resize like Bicubic.

[permetaform]

but what if the input .avi is 16:9 and it outputs 4:3?

Does it matter if there's black bars on the top and bottom of it? (it's dvd ripped but very very long, I think it's almost 3:1)

[absolutedestiny.livejournal.com]

What are the resolutions (frame sizes) of your input and output videos?

Use the File> File Information option in virtualdub to confirm the input resolution.

Also, what is the format of your source (codec etc)?

[permetaform]

720x480 at 29.97 fps for input. codec is...Sony DV software?? ::confused expression:: er?

Output *says* 720x480 at the same framerate, but it *looks* stretched, and the codec is DivX.

[absolutedestiny.livejournal.com]

What you might be noticing is differences in playback.

Divx play back its videos with a square pixel aspect ratio, so 720x480 is 720x480.

DV will play with a 0.9 pixel aspect ratio similar to TVs so that 720x480 will be scaled to 640x480 on playback. This gives the correct 4:3 aspect ratio when viewing on a monitor.

Try resizing to 640x480 and see if that looks the way you expect.


Ideally however, you will want to crop your footage to remove any black bars and resize the final thing to whatever aspect ratio the movie is supposed to be (16:9, 2.35:1 etc) - what movie/show is your footage from? Can you post a picture of the image you get in virtualdub?

[permetaform]

Try resizing to 640x480 and see if that looks the way you expect.

::nods:: will do. I was wondering if there was someway around that post-rendering, but I guess not.

The footage is from Pirates of the Caribbean. The screenshot is available here. Tell me if you need a clearer pic or a different file on there...

[absolutedestiny.livejournal.com]

OK you essentially have two issues.

The first is that the footage is anamorphic (enhanced for 16:9 TVs)

THe second is that the footage is TV-style pixels (which aren't square)


Presuming this is for a net distribution, given the image you posted, the things you need to do are as follows:

1) In vdub, go to Video > Filters and add the "null transform" filter.
2) Highlight this filter inyour list and choose "Cropping..."
3) Crop 54 pixels from the top (Y1 offset) and another 58 from the bottom (Y2 offset)
4) OK and go back to the filters list. Add the "resize" filter.
5) Select one of the Precise Bicubic options and enter a new size of 640x272

This should correct the footage perfectly to what it needs to be.

However, note that if your footage is interlaced, this resize will blend the interlaced fields. You can avoid this by resizing to 880x368 (which is large) or 440x184... or you can deinterlace the footage.


Hope this helps and isnt too confusing :)

[permetaform]

Oh god, that's extremely helpful. ::bows at your feet repeatedly:: THANK YOU. wow.

[absolutedestiny.livejournal.com]

I'm expecting you to have some interlacing issues, given the DV source footage.

Divx isnt great for compressing interlaced sources, so what the easiest thing for you to do would be is to add the "deinterlace" filter and move it to the top of the filter list. (There are much better ways of deinterlacing but this will suffice for now)

Of course, I am simply presuming that all of this is for an internet distribution and not for editing with later - please correct me if I'm wrong :)

[permetaform]

yup, internet distribution. I'm messing around with codecs and VDub and bitrates to suss out the smallest file at the lowest quality I'm willing to stomach while waiting for my betas to get back to me. I'm liking the result I'm getting for 800, tho I think people might complain that 30mb is too big. ::rolls eyes:: I'm also not sure how many people have Divx...tho I'm pretty close to just throwing up my hands and going, "Deal."

[absolutedestiny.livejournal.com]

I'm not entirely sure how it developed that the AMV community became accustomed to high quality large encodes for its videos but it's considered a standard now whereas the vidding community seems much more accustomed to smaller encodes. I have an average file size of around 40mb for my videos.

I'm very picky when it comes to quality but that's just a personal preference.

[permetaform]

I'm very picky when it comes to quality but that's just a personal preference.

eh, you're not the only one. If you do something and put your name on it, do it well, no?

[par-avion.livejournal.com]

At this point, I think many people can play divx. Certainly I've DLed at least ten non-anime Dixv vids...and I don't DL randomly, only by rec or if I know the vidder.

Hell, I'm on a mac, and I have can watch Divx (using the extension for quicktime). For the most part. I wasn't able to watch Lum's recent Divx of "Evil Angel" and I haven't figured out why.

I don't think 30mb is too big (for me to DL -- I have a cable modem) if the vid is high quality. I think one of the differences between AMV and the other vidders is that the AMV is centrally hosted. The only issue there is how big a file is someone willing to DL. The other vidders host their own vids and are worried about bandwith, so there are two pressures there.

[permetaform]

I think one of the differences between AMV and the other vidders is that the AMV is centrally hosted. The only issue there is how big a file is someone willing to DL. The other vidders host their own vids and are worried about bandwith, so there are two pressures there.

I forgot about that! And your right, that'll probably affect size/quality as well.