You may have noticed an innocent little setting in the options dialog called DVD aspect ratio. It allows you a single choice between 4:3 and 16:9.
You might think this will cause everything on the disc to be rendered as 4:3 or 16:9. However, as you may be aware, DVD’s allow a mixture of aspect ratios on a single disc. You can see this frequently on Hollywood discs where the main feature will be 16:9 and some of the extras may be 4:3.
We wanted DVD Maker to support generating DVD’s like these, so you can freely mix content of different aspect ratios on the same disc. When you add a video we will automatic detect its aspect ratio and render them appropriately either as 16:9 on the disc or as 4:3.
For DVD Menus, we will automatically generate them as 16:9 but we also specify the information so they can be rendered as 4:3 on a 4:3 display. This way the user doesn’t have to specify anything and they’ll get the desired behaviour of a menu that fills the screen. So for example if you have a 4:3 TV you should see a menu something like this.
and if you have a widescreen display you’ll see a menu something like this.
So if we do this stuff automatically, what does the setting in the option dialog do? Well for slideshows we can’t really determine the aspect ratio automatically, as images aren’t normally all 4:3 or all 16:9 so for slideshows we will use this setting and generate them as either 4:3 or 16:9, depending upon what you choose.
Windows Movie Maker project files gave us a little dilemma. Movie Maker for Windows XP and earlier doesn’t store the aspect ratio in the project file. Movie Maker uses a global option based upon the settings in its “Options” dialog. So when you add a Movie Maker project file to Windows DVD Maker we faced a choice, we could either use the current aspect ratio settings in the Movie Maker options dialog or use the settings in the DVD Maker options dialog. None of these choices were ideal, Movie Maker’s options may have changed since the project was saved and DVD Maker’s options might be different to the options in Movie Maker when the user created and edited their project.
To work around this problem, we changed Movie Maker in Vista so that it now stores the aspect ratio in the project file. This way every time you load a project in Movie Maker it will automatically switch to the aspect ratio that was being used when the project was saved. When you add the project to DVD Maker then DVD Maker will also use that aspect ratio. We can now be sure of using the correct aspect ratio and you can even add multiple Movie Maker project files with different aspect ratios and we’ll use the correct one for each. You can see this below where I added two project files, one that was created as 16:9 and one that was created as 4:3.
So this just leaves Movie Maker project files that were created in Windows XP or earlier which don’t hold the aspect ratio, so for those we’ll just default to the aspect ratio specified in DVD Maker's options dialog.
So to summarize, the aspect ratio setting within DVD Maker is mainly just used for slideshows and we’ll pretty much handle everything else automatically. So if you’re creating a slideshow and you know you’re mainly going to play back your DVD on widescreen displays choose 16:9, otherwise choose 4:3.