aspect ratio in mainconcept encoder confusion

[niftybabs]

ive just started using mainconcept after tmpegnc started refusing to work, and am a little confused about aspect ratio. when using tmpegnc i would use 'full screen (keep aspect ratio)' and was happy with the results, in mainconcept im trying to encode xvid to svcd so in the drop down aspect ratio box i can choose either 4.3 or 16.9 when choosing 16.9 the movie is squashed and when choosing 4.3 the movie is stretched. Is there anyway i can keep the screen the same as in the inputting xvid video?
hope this makes sense as its been puzzling me for days and all searches bring no joy.
thanks.

[greengate69]

You can use the crop and scale feature of Mainconcept or you can prepare the input file (e.g. virtualdub) and frameserve the letterboxed result to the encoder. If you put "Mainconcept Aspect Ratio" into the Forum Advance Search on this site you will see many topics including detailed examples and guides.

[niftybabs]

okay ive been searching and am even more puzzled, i guess i have to crop and scale the film but am lost as to how i work it out. the size of the xvid is 512x384 and i want to convert it to PAL svcd to watch on a widscreen set. any help much appreciated.

[Abond]

You can use FitCD to get the values, select anamorphic for output.

[Gurm]

Or you could use a calculator. It's simple - here!

If the video is 512x384, and you want to fit it onto an NTSC SVCD (I know you're PAL, gimme a minute), you do the math like this...

It's set up for square pixels on a monitor. The vertical resolution target is 480. On a monitor, that resolution is 640x480. So the width target is 640.

640/512 = 1.25
384*1.25 = 480

So on an NTSC set, that movie would be 480 tall by 480 wide (we toss out the 640 when talking about SVCD).

Now, in YOUR world, you need to figure out what the target would be for a square pixel at 576 high.

576/480 = 1.2
1.2*640 = 768

So the resolution on the PC that you're targeting is 768x576. The 768 will get tossed in favor of 480, but it's useful for our initial calculations:

768/512 = 1.5
1.5*384 = 576

So in this case, you want 480x576. Yeah, it turned out to be exactly the same. It's a 4x3 image, so what did we expect?

[Gurm]

Ok in case that last answer seemed long to get to an obvious answer:

You're watching a 4x3 video on a monitor. You want it to end up being a 4x3 video on a TV.

Now, there is another step if your TV is setup to stretch all videos. But how about the easy answer - turn off stretching.