Configuring Project Settings > Project Settings > Effects (Subtitle Presentation)

The following notes apply to classic 4-colors DVD authoring systems and tools. BluRay and HD-DVD systems use newer technology without restrictions to the number of colors used.

DVD authoring systems accept subtitles as rendered images in the Windows bitmap (with a .BMP extension), TIFF (with a .tif extension) or Portable Network Graphics (with a .PNG extension) formats.

These images, however, must follow some rules and one of the most important ones is that a single image cannot display the text with more than 3 colors. The 4th color is reserved for the background of the images which needs to render as fully transparent on the viewers screen. Presentation style for DVD subtitles is limited to text and background colors and choosing two out of three possible effects: box, outline and anti-aliasing.

It's sadly not possible to create DVD subtitles that have the three effects in one image. If you proceed to export such a project EZConvert will disable one of the applied effects.

Every classic 4- colors DVD authoring system has its own default color palette to choose text or effects colors from. The respective color lists are updated automatically when changing the DVD authoring system in Project Settings. Colors in the particular color palette can be modified from the export settings available for each of the classic DVD Systems.

You may also notice that the subtitles look a little squared when anti-aliasing is applied. That is so because it isn't possible to perform a full anti-aliasing without alpha (transparency). But the quality of the images produced that way is still considered acceptable because the subtitles are not meant for HD resolutions.

Another important point to make is that EZConvert takes into account the pixel aspect ratio and sometimes this may distort the rendered images. To compensate for the pixel aspect ratio you could scale the display fonts horizontally: 106%-107% for PAL or 90%-91% for NTSC.