Aspect ratio(s)

[jim]

Hi,

A question about tmpgnec and aspect ratio's.

If I DL an avi in 16:9 aspect, and I want to make a (S)VCD to be played on my standalone player, and viewed on my 16:9 TV, what do I do ?

I have DL'ed some (s)vcd's that fit the 16:9 tv, so it can be done. But whenever I make a vcd, I have to use the tv's zoom feature.

So what do I select in the tab "Video" in field "Aspect ratio", and what do I select in the tab "Advanced" in field "Source aspect ratio", and do I need to do anything else ?

What if the avi is 2,35:1 ?

thx
Jim

[Darrell]

I don't know if this will help...but this is what I have learned to do.

First let's start with a given. On a standard TV the resolution is 4:3. There are 16:9 tv's out there but I don't have one... so going with what I know...There is a peculiar feature that all standard TV's have called overscan. That means there is part of the picture you will never see because it extends past the physical dimensions of the crt(picture tube). It's normal..You can't get around it unless you know how to change the horizontal and vertical(width and height)inside your set. You don't want to...take my word for it.

Now lets talk about a 16:9 movie. Don't want to encode the borders that come with the dvd?...Clip them off. All the way around. Bare in mind that to display the correct aspect ratio..you WILL have black borders.
So why clip them off if you need them?
Have you ever seen encoded black borders from a dvd??? They aren't pretty.They have a bad habit of not staying pure black during playback. I get alot of nasty dark red macro blocks.

Now the problem is, if you go for full screen after that...the res is ALL wrong..if you have a movie like "Independence Day" You have to manually adjust the res anyway because anywhere except your DVD player,it is displayed wrong. So full screen (maintain aspect ratio)negates the clipping you just did and you are back at the wrong resolution. Then you have the option of Center(maintain aspect ratio)...this clips off Too much of your picture. You lose too much video. What I'm getting to is this... Center(custom size). This is a 2-fold solution. You can maintain the clipping of the black borders you just accomplished and you can adjust for the correct resolution.

Oh..one more thing. Don't try for full width...it goes back to the overscan thing I told you about with tv's...Why encode what you can't see? The rule of thumb seems to be adding a 16 pixel border to each side and adjusting the vertical from there to get the correct aspect ratio. You could adjust it to suit your taste.

An example is this:
Lets say you have a movie that for reasons known only to you, is to be encoded at full dimension (720/480) and it has the (approx)64 pixel top/bottom borders that so many have. Clip them off..same with the left and right. You may be left with 720/306 or 704/300 or any variation in between...the thing is...the correct aspect ratio will always be 2.35
Now...since some(most...all)dvd players have a problem with odd sized video, the encoded movie STILL needs to be 720/480.
Simple enough..on the video tab, you choose 720/480. BUT in the Clip Frame part subtract 16 pixels (center[custom size])from each side, then take that part of the resolution(688 in this case)and divide it by 2.35, that will be the height. it comes to 292.76...make it 292 or 294.. 688/294=2.34 and 688/292=2.356.

For a svcd movie it would be (lets see...)480x480 subtract 32 from total width...448.

448*2.35=196.3....but since the format is square, the res still would not be right, so multiply your answer by 1.5 (which is what is viewed on a dvd player..) and you have 285.95 or 286. So the resize would be 448/286 for a 16/9 movie made as an svcd. Now the playback res is correct.

Does any of this help or have I totally pissed you off?

[jim]

You are not making any sense at all. But thx for trying.

I think I'll wait untill someone who has tried this in real life, posts a reply.

My question was:
"If I DL an avi in 16:9.."

And your answer is:
"Don't want to encode the borders that come with the dvd?..."

I can't see the connection....

"Simple enough..on the video tab, you choose 720/480." What version are you using ? I don't have that choice.

/jim

[Darrell]

I was trying to tell you how to make a rip with the correct aspect ratio of 2.35(16/9)..made perfect sense to me at the time...still does. But then again I did drink alot of beer last night.

[friar01]

not sure if this is what you're looking for, but when i use tmpgenc, i just select both ratios to be 1:1. i know this sounds f'ed up, but that works for me every time, and i don't have a problem with the video being distorted as a result of an incorrect aspect ratio. but just to make sure, you can always use the preview feature (one aspect of tmpgenc that cce doesn't have) to make sure te video looks right. again, i'm not sure if this is the answer you're looing for, but i thought i would try. good luck!

[friar01]

hey, i was just browsing through the forums, and saw this one:

http://forum.doom9.org/showthread.php?s=&threadid=5905

it seems to address the issue of aspect ratios pretty well. i only read bits and pieces of it, but it looks like it might be able to help you out.

[jim]

Yeah, except that they talk about dvd's and dvd2svcd.

I ask about avi's, and tmpgenc.

/jim

[Stabmaster-Arson]

OK now for the voice of reason. In tmpgenc, in the options, set the video source as 1:1(VGA) and set the new encoded format to be 16:9 525 line NTSC.

or 16:9 625 line (pal) if you are pal.

then set the proper resolution, 352x240 for ntsc or 352x288 for pal, etc and it will look right.

[jim]

Well, I have now done some testing on my own.

I've found out that I have to select in the tab "Video" in field "Aspect ratio", "4:3 display"; and in the tab "Advanced" in field "Source aspect ratio", "16:9 display".

thx ? for the theoretical input ....

/jim

[Wilbert]

To Darrell:

"An example is this:
Lets say you have a movie that for reasons known only to you, is to be encoded at full dimension (720/480) <...>.
For a svcd movie it would be (lets see...)480x480 subtract 32 from total width...448.

448/2.35=190.6 .... but since the format is square, the res still would not be right, so multiply your answer by 1.5 (which is what is viewed on a dvd player..) and you have 285.95 or 286. So the resize would be 448/286 for a 16/9 movie made as an svcd. Now the playback res is correct. "

(I corrected two typo's ...)

Why do you multiply your answer (that is 190.6) with 1.5 ???

I understand that when viewing it the resolution becomes 448x252 (=16:9) so the image is stretched by 252/190.6 = 1.32 vertically.

Please help me ...

[SupaCoopa]

I recently bought a widescreen TV and had to re-encode all my DivXs to widescreen SVCDs. TMPG does a really good job and the proccess is quite straightforward.

First: All DivXs are 1:1 aspect ratio. So choose this under "Advanced" "Source aspect ratio".

Next: Choose "16:9 Display" under "Video Stream" "Aspect Ratio". That's all you need to do. No need to calculate pixels, divide, multiply etc. TMPG does this for you.

Last: Go to "Clip Frame" under "Advanced" . There you'll find "Arrange Setting" with preview. You can choose any mode you like, if you have a 2.35:1 movie you can make it 16:9 full screen or 16:9 letterboxed or whatever. You can even turn a 4:3 to 16:9. Just make sure you choose options with "Keep Aspect Ratio" in them or the movie will be distorted.

Hope this helps

[Wilbert]

I can't choose 16:9 display under the video tab (use version 2.50 and 2.52). I thought svcd was always 4:3 display.

I want to calculate that stuff, because I want to know how it works.
I also want to resize in VDub, because I think the quality will be better.

Anyway, I think I know how it works now:

The source was 720 x 480 (2.35:1). It must be resized to 448 x something and black borders will be added after that, because of the overscan feature of our TV.

The source is equal to 448 x 190.6. Further more 480/576 = 448/537.6. Thus after resizing when playing full screen (448x336) the vertical size of the image will be

190.6 * 336/537.6 = 190.6 * 1.6 = 305

So it's actually multiplying with 1.6 instead of 1.5, but ok. Since the vertical resolution must be a multiple of 32 we take 9*32 = 288 (but I guess we can also take 10*32=320). After resizing black borders will be added to obtain the resolution 480x576.

[Darrell]

Get a program Called FITCD. It does all the resizing for you to make it correct. Mind you, it writes it to an AVS file, so Tmpg has to have the plugin that allows it to read avs files. What I did was simply transfer what it did in the AVS, to my clipping and resize options in Tmpg. Then you simply adjust to taste.

[jim]

To SupaCoopa.

"First....."
"Next......"

Great. Just what I was looking for !

"Last: Go to "Clip Frame" under "Advanced" .....

Is this last step neccesary if I want 16:9 movies to fill my 16:9 tv, and 2,35:1 movies to have small black bars over and under the picture ? Don't I just keep the "Full screeen (keep aspect ratio)" selection in the "Video arrange method" field, just under the "source aspect ratio" field ?

Jim

[SupaCoopa]

Jim, sorry for the late reply.

"Full screeen (keep aspect ratio)" is the right choice for widescreen to widescreen operations. With a 1,78:1 source you get full widescreen. With a 2,35:1 source you get letterboxed widescreen. If you have a 2,35:1 movie and want to make it 1,78:1 (ie no black bars up and down) you can fiddle with the other alternatives. This will of course result in loss of right/left parts of the picture.

If you have a 1,66:1 or 1,33:1 movie, it's zooming and cropping again ("No margin Keep Aspect Ratio") if you want full widescreen. This is preferable to using your TV set zooming feature at playback.

Cheers

[jim]

Better late than never :D

"If you have a 4:3 movie.....if you want full widescreen" and I don't. I wan't the full movie, and I don't wan't to use my TV's zoom.

Have already converted some mov's as per U'r instructions, and they work great.

/jim