User manual

Figure 1C – Interlaced.Figure 1A – Odd. Figure 1B – Even.
Designing a menu
Now that you better understand how images display on a TV, let’s present some guidelines for designing DVD
menus.
Horizontal Lines
Horizontal lines present one of the most common issues with DVD menus. During scanning, if a horizontal line
is too thin it can be visible in only 1 eld of video. Since the cathode ray alternates scanning between odd and
even elds, the line will seem to appear and disappear causing it to twitter or icker. By keeping horizontal
lines no thinner than 3 to 4 pixels thick you can help avoid this issue. You can also try shifting the line a pixel
or two up or down. Sometimes this will alleviate the problem.
Fonts
Fonts can be an issue if not used carefully. It’s recommended that Serif fonts be avoided. Serif fonts have
small design details that often consist of horizontal lines. These elements can cause twitter. It’s best to stick
with Sans Serif fonts, but there are no hard and fast rules when it comes to designing graphics for display on
a TV. Just because a font is Sans Serif, it doesn’t mean it will work as different fonts have different styles.
Font size can also be an issue. A font that’s too small can
buzz, crawl, or mosquito. It’s generally accepted that font
sizes smaller than 18-20 points should be avoided. Although
this is a good starting point, it’s not a rule. Different fonts can
be larger or smaller than one another even though they may
be the same point size. This is a good time to check things
on your monitor. No matter what the point size, if it doesn’t
look right, don’t use it.
Some experts recommend adding a very slight blur to text that doesn’t display well. Sometimes that effects
the readability of the menu. Another approach is putting a drop shadow or a glow on the fonts. This not only
can help reduce artifacts, but it can add to the readability of your menu. If you’re careful when choosing fonts
and test your menus on a monitor, you shouldn’t have any need to add a blur.
Chrominance (color)
As covered in Part I, staying within the NTSC color safe limits is important – but it is no guarantee. Colors,
especially red and yellow, if too hot (bright), can mosquito or crawl. A good place to start is adjust them to
within the NTSC limits. Review your menu on a TV and if those colors look bad, you will need to go back and
drop the saturation until it looks OK. Working within a single color palette is a great way to reduce artifacting.
Use a light blue font on top of a darker blue background. This makes it easier for the cathode ray to adjust
between the two areas of the image.