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fabriciomicheli
07-07-2005, 01:20 PM
Hi there:
Im making a project that's a 3 minute animation film, and the output for it is a DVD-PAL format to watch it in home DVD based systems.
I was looking for information and I considered to render my frames in a 720 * 432 resolution which means an aspect ratio of 1.67.
I'm just wondering if these data (size and ration) are right or maybe I need to consider another ones. I never made a film for DVD output and I dont have experience to define which is the best resolution or ratio I can work with.
Another thing is that I cannot go for an higher resolution (HDTV for example) because my hardware configuration is just decent and i need to keep the render times low enough to get the deadline.
Please any information you can throw me will be really helpful.

Thanks a lot in advance guys,
Fabricio.

Kai01W
07-07-2005, 09:30 PM
Hi there:
I was looking for information and I considered to render my frames in a 720 * 432 resolution which means an aspect ratio of 1.67.
Thanks a lot in advance guys,
Fabricio.

You should not forget that PAL has not square pixels but a pixel aspect ration of 1.066 so in order to achieve a 1.66 aspect ratio on your tv you should go for 720*460 pixel (if my math is correct ;-) )

-k

fabriciomicheli
07-07-2005, 11:40 PM
well, I think I got wrong, I was talking about a 2:35 aspect ratio, but take a look at this: http://www.videohelp.com/forum/userguides/174200.php

that's the site where I got the info.
Anyone has experience in making an animation for DVD output? heeeeeelp please!!!

Studev
07-08-2005, 01:05 AM
Simple...the final output will be still at 720 x 576, otherwise your DVD player won't read it !! you can't run away from that. To achieve that kind of aspect ratio that you're talking about, simply put a black borders on top and the bottom through the entire sequence. You can cheat it by doing that if you can afford to lose some of the pixels on top and bottom.

I don't know what kind of video editing application you use. The non square pixels is handle automatically if you set it for PAL. It's 1.067 if i'm not mistaken. It's not a problem at all.

Unless you're talking HD DVD, that would be a different thing to discuss. It's entirely a different process which i'm getting to know bit by bit about it.

Regards

Hugh
07-08-2005, 08:48 AM
Resolutions and pixel aspect ratios! I spent far too much time about a year and a half ago getting my head around them.... fair to say, I now do feel like I understand what's going on...


PAL is 720x576 with a 1.067 pixel aspect ratio (PAR)

If you want to render stuff with square pixels and then convert it to PAL, you want to render at 768x576 and then resize to 720x576 (or start at 720x540 and resize up, but resizing down is better)

If you want your actual image to have a 2.35 aspect ratio, then, when using square pixels, your working resolution should be 768x327 (327 = 768/2.35). This can then be padded with black top and bottom to get 768x576 and then squashed to 720x576.

For other actual aspect ratios, substitute them in for 2.35 above (1.85: 768x415, 1.66: 768x463)

If you want to render directly to the output resolution, replace the 768 by 720 and render with a PAR of 1.067.

Hope this helps!

gi-jones
07-08-2005, 09:03 AM
The case is, that dvd's er almost always produced in anamorphic widescreen. This means, the picture is actually stretched to fill out the entire resolution, and then compressed vertically on the screen. This way you can take advantage of the full resolution and thus get a better quality picture.


I messed around with rendering directly to an anamorphic resolution a while back and it is rather easy (at least in 3dsMax).

You need to do your output settings like this:http://www.eyesdata.dk/res.jpg

It is done by first setting the resolution and the adjusting the pixel aspect until the Image Aspect is as near 1,778 as you can get (16/9 = 1,778)

Hugh
07-08-2005, 09:19 AM
That's a good point....

The official PAR for 16/9 PAL is 1.4226666666

If you want to render with square pixels and then squash to this, your rendering resolution should be 1024x576

fabriciomicheli
07-08-2005, 11:37 AM
oh guys, first at all, thanks a lot...

Second, im a little confused right now...
let's see:
If I want my movie in DVD format to look like widescreen (16:9) aspect ratio... what i need to do is: render in 720 * 576 and use black bars above and below the area to "simulate" a widescreen format?
that's the only way?

thanks a lot Hugh, gi-jones, studev and Kai01/w

Hugh
07-08-2005, 11:43 AM
Nope - 'fraid not....

If you want it to look widescreen, the best solution would be to render it at 720x576 with a pixel aspect ratio of 1.4226667

Then, when creating the DVD, make sure the '16:9' flag is on (I have no idea where this is, but there must be something in a DVD to say what the aspect ratio is....)

fabriciomicheli
07-08-2005, 12:02 PM
oh got it Hugh!!!

and last question? do i need to have a widescreen TV to see the movie? or in a standard format (4:3) i can see it anyway...? really appreciate your help man. Thanks a LOT :thumbsup:

gi-jones
07-08-2005, 12:22 PM
Hugh: Usually it can be done, when compressing to MPEG2. Somewhere in the encoding program you can specify which aspect ratio should be used when playing the file back (it doesn't change the actual resolution).

fabrizzzio: It obviously looks best on a widescreen tv, but if the dvd-player is setup correctly (you can specify which tv you have in its menu somewhere), if will "squash" the film and show black bars on a 4:3 tv. It is exactly the same way any dvd, that you may buy somewhere, is made.

Kai01W
07-08-2005, 12:30 PM
oh got it Hugh!!!

and last question? do i need to have a widescreen TV to see the movie? or in a standard format (4:3) i can see it anyway...? really appreciate your help man. Thanks a LOT :thumbsup:

Most modern TVs even if they are 4:3 have a 16:9 modus which squezes the image. Uncertain about older TVs though...
If you decide to go for normal PAL with bars. I'd recommend to render just the res you need and extend later with black to full 576. Might save you some rendertime.
If rendertime is not an issue you could of course render full 576 pixel height and thereby save the possibility to correct framing in post a little.

As Hugh said, this whole topic is a little confusing but once you understood the basic concepts it just a matter of doing the math right (or having the software do it for you ;-)

-k

fabriciomicheli
07-08-2005, 01:12 PM
...if will "squash" the film and show black bars on a 4:3 tv. It is exactly the same way any dvd, that you may buy somewhere, is made.

oh man, I see... but, what is the standard resolution for an ordinary film or movie in DVD format?

Studev
07-09-2005, 01:36 AM
I have ever did the anamorphic before. During the encoding, the wide screen format become stretch vertically throught out the whole movie. It becoming 4:3 instead of 16:9.

Hugh are you sure, that you can renderered in anamorphic aspect ratio and maintain it during the encoding process ? and the DVD player will read ?

Hugh
07-11-2005, 09:34 AM
Hugh are you sure, that you can renderered in anamorphic aspect ratio and maintain it during the encoding process ? and the DVD player will read ?

When looking at anamorphic footage of any kind without resizing the pixels, it will look stretched. What the DVD player or TV should be able to do is resize it so that it looks correct.

gi-jones
07-11-2005, 09:38 AM
Standard resolution is 720X576 (that's PAL, I don't remember the NTSC standard)

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