04 February 2011

Authoring a DVD with mixed 4:3 and 16:9 content

Last week I was quickly throwing some short films onto a DVD project, and somehow I stumbled across a method of authoring a DVD which correctly displays 4:3 and 16:9 movies without any unwanted scaling or stretching of the picture.

Firstly, some provisos...

This tutorial requires the iDVD software running on an Apple Mac computer.  Unfortunately I don't know of any similar solutions using Windows software, although I'm sure they exist.  I was using iDVD 7.0.4 within Mac OS X 10.5.8, but any version of iDVD with widescreen options should work fine.

The finished disc worked perfectly with the Panasonic Blu-ray player and HD projector used by Huddersfield Film Makers Club.  However when tried at home with a cheap DVD player and widescreen TV, the 4:3 videos did not display correctly; they were scaled up to fill the width of the frame and therefore the top and bottom portions were cropped somewhat.  I suspect this is a function within the DVD player but there were no options to adjust it.  So this is not a foolproof method but it does work with our club's display equipment.

How to do it

If you've already exported a high bit-rate file of your video, feel free to skip the first step. 
  • Export your videos from your editing software. Export using the ‘Current settings’ that you edited with -- don't worry about making any changes to the frame aspect at this stage.  If you have the option to ‘Make movie self-contained’, un-check this box. The editing software will now make a small reference movie file which does not contain any media but points to your captured media that is already on your hard disk.  (Note: to learn more about reference movies and how they can be useful, see this Larry Jordan article.)
  • Open iDVD from the Applications folder and create a new DVD project. From the menu choose Project > Project Info and make sure the project is set to 16:9 frame aspect ratio (see below). After setting this you may be asked to reload the project theme or choose a new theme.  You will notice the DVD menu screen is in widescreen format, if it wasn't already.
  • Find the reference movie that you created earlier, and drag the file icon directly into the iDVD project. A button will appear on the DVD menu (usually a text button showing the filename of the reference movie). iDVD will start encoding the video, either immediately or when you ask to burn the disc.
  • Add any other movies that you've prepared.  Whether they are 4:3 or 16:9 they don't need any special preparation, just drag them straight into the DVD menu.
  • When you burn the disc, iDVD will finish encoding and then write to your blank DVD disc.  When it's done play the disc and check the results.  The 4:3 videos should appear in their proper frame aspect, displaying black borders on the sides to fill the widescreen frame.