Aspect Ratio's

[AndySpring]

I am new here so firstly hi all.

My aim is to capture a dvd and convert it to wmv and mpg.

The DVD has a video size of 720*480 and an aspect ratio of 4:3, as I understand it the first refers to the storage and the second to the display size. Is that correct?
If so, am I doing right in capturing at 720*480, then doing the editing etc, save as a uncompressed avi before I convert using media encoder at a ratio of 4:3 e.g 640*480?

Many thanks for any feedback in advance.

[freebird73717]

If you have a dvd drive in your computer you can just rip the dvd to your hard drive using dvdfabdecrypter. Run it through dgindex then resize and apply whatever filters with avisynth (easy scripts with fitcd). Load your avs file created by avisynth into your encoder and encode away. It may seem like a lot of steps but it should provide better quality because you're not converting it twice.

[AndySpring]

Thanks for the reply; I am a bit confused as to why I am converting twice? Also was I right about the ratios part do you know?

[redwudz]

I assume you know that's a NTSC framesize (720 x 480) and since you are in PAL land the framesize there is usually 720 x 576. I ask because the frame rate for PAL is 25fps and NTSC is 29.97 or 23.976fps. As long as you are planning on playing it back with the computer, it makes no difference, but for TV you would need a NTSC capable player or a framerate conversion.

For aspect ratio; From our GLOSSARY:

Aspect Ratio
The width-to-height ratio of an image. A 4:3 aspect ratio means the horizontal size is a third again wider than the vertical size. Standard television ratio is 4:3 (or 1.33:1). Widescreen DVD and HTDV aspect ratio is 16:9 (or 1.78:1). Common film aspect ratios are 1.85:1 and 2.35:1. Aspect ratios normalized to a height of 1 are often abbreviated by leaving off the :1.

You can also use a program like VOB2MPG to extract the decrypted DVD to one large MPEG file, then you can convert it to any format you want. Or if you wanted Xvid or Divx formats, AutoGK or FairUse Wizard or avi.NET may be easier for conversion from DVD.

And welcome to our forums.

[edDV]

Some basics.
DV and DVD do not use square pixels. I'll assume 704 = 720 for this overview.

NTSC _4:3 saved file = 720x480 and is displayed as square pixel 640x480 or upscaled
NTSC 16:9 saved file = 720x480 and is displayed as square pixel 853x480 or upscaled

PAL _4:3 saved file = 720x576 and is displayed as square pixel _768x576 or upscaled
PAL 16:9 saved file = 720x576 and is displayed as square pixel 1024x576 or upscaled

[jman98]

Thanks for the reply; I am a bit confused as to why I am converting twice? Also was I right about the ratios part do you know?

Because you also said:

My aim is to capture a dvd and convert it to wmv and mpg.

Conversion #1 - to WMV
Conversion #2 - to MPG

It isn't required to convert to AVI and edit there. There are several very good MPEG-2 editors available, such as MPEGVCR and VideoReDo.

By the way, why are you capturing in NTSC since you live in the UK? I would think you would use PAL.

[AndySpring]

I was not sure that it was the NTSC framesize but as they were shipped from a content supplier in the US i thought it would be. The DVD's are for playback on computers so that should not be an issue.

Thanks for the suggestion, there does seem to be a number of ways to do it. Is there anything inherently wrong in the way i am doing it?

and thanks for the welcome, seems to be a great and very helpful forum

[AndySpring]

jman98 sorry i see the confusion now. The end movies will be avalible for download (hence keeping them in ntsc) and i want to offer both a wmv version to download and a mpg version