STANDARD DEF AND HIGH DEF COMMERCIALS

As more and more consumers switch from SD to HD televisions, the demand for commercials to be delivered in Hi-Def also increases.

Even though most of our commercials are now available in HD, we still need to look after the SD market because some stations still only air commercials in SD format.

We add this note to our TV traffic instructions:

“SPOTS ALSO AVAILABLE IN HD FORMAT. STATIONS AIRING IN HD SHOULD RUN THE HD VERSION. IF YOUR HUB ACCEPTS BOTH HD AND SD, MAKE SURE TO LETTERBOX WHEN DOWNCONVERTING (4X3 SAFE).”

What does that mean? What is 4 x 3 SAFE?

Here’s a basic, jargon-free explanation:

Most television sets are adjusted to show less than the full picture. The accepted convention is that the graphic image (picture) should be kept to the center 90% of the of the image area (known as the “safe” area) and any text should be kept to the center 80% of the image area (known as the “title safe” area) to ensure that none of the image is cut-off to the viewer.

High Definition TV screens show a wider picture- it looks more like a rectangle than a square, and the picture fills up the whole screen. If you show a HD formatted picture on a SD screen, the sides of the picture will be cut off because the rectangle-shaped image is being fit into a square format.

So…. If you show a HD spot on a SD transmission, you will lose even more of the safe area of the image. To fix this problem, the commercials are “letterboxed” by adding black bars above and below, or on all sides of the image (called "pillarboxed"), therefore preserving the entire picture as it appears on the TV screen and making it fit into the “safe” area.  

Same goes for viewing an SD spot on a HD television. Because the SD image is square not rectangle, black bars will appear at the sides of the image in order to fill up the HD screen.
Here's a visual example, courtesy of our friends at CTV-