1920x1080 plays with letterbox in full screen mode

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Level 1

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1920x1080 plays with letterbox in full screen mode

Hi, everyone. I have a 1920x1080 square pixel (16:9) video file (H264). When I play it in QuickTime's normal mode, it displays fine.

When I enter Full Screen mode, it appears letterboxed (black at the top and bottom). The aspect ratio doesn't change (nothing's distorted).

I've supplied the file to an AV person who will use Full Screen mode to project it onto 16:9 LCDs for an event. He's told me that the file isn't 16:9 because it displays this way. I know 1920x1080 is 16:9, so my feeling is QuickTime is somehow not handling the file properly. Does anyone have any suggestions or insight into how/why a 1920x1080 file would appear letterboxed in Full Screen mode? Is there a way to fix this?

Any advice would be greatly appreciated.

Posted on Sep 16, 2011 11:29 AM

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Answer 1

Jon Walker

Level 6

19,467 points

Sep 16, 2011 3:30 PM in response to lchap

Does anyone have any suggestions or insight into how/why a 1920x1080 file would appear letterboxed in Full Screen mode? Is there a way to fix this?

There is probably nothing to fix. As can be seen in the first image, the 16:9 movie in the QT X player does not cover the entire desktop. This implies that your monitor is not displaying a 16:9 aspect ratio. Therefore, in the full screen mode the "widscreen" movie is scaled to "fit" the width of your monitor and the excess area above and below the 16:9 display area (i.e., the desktop in the first image) is filled with a black background creating your "letterbox" effect. In other words, your movie will fit your monitor exactly if, and only if, both the movie and the monitor have the same aspect ratio.

If you also have QT 7 Pro installed on your computer, then try viewing your movie in its full screen mode which allows the movie to display using either the "fit" display algorithm or the "fill" display algorithm. In the latter mode, the "widescreen" movie will be scaled to the height of your monitor display. Since this overscales the width of your movie, the left and right edges are cropped from view but the enire screen is filled with what is left of your movie image. In addition, QT 7 also allows you to select a color other than black as "full screen" filler for the "fit" mode when the movie and monotor display area aspect ratios are not the same.

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Answer 2

Sep 19, 2011 4:04 AM in response to lchap

You don't specify which model Mac or which make/model of display you are using.

For your information older model Macs used to have a 16:10 screen. This means playing a 16:9 movie on them quite rightly results in a small black border top and bottom. The new iMac, MacBooks and new Thunderbolt screen all are 16:9 so should not have a black border top and bottom. However be aware that many movies are not 16:9 they are what used to be called 'cinemascope' meaning they are even wider screen than 16:9. These should therefore show with black borders top and bottom even on a 16:9 screen.

Philips actually make a super widescreen TV to better matter these sort of movies which has a 21:9 aspect ratio, see http://www.philips.co.uk/c/televisions/cinema-219-platinum-series-147-cm-58-inch -ultra-wide-full-hd-3d-max-58pfl9956t_12/prd/

The example video you show in your screen captures is a 16:9 and not a cinema movie feature film so you will not have black bars. However something like a film like Iron Man would.

A display with a true resolution of 1920x1080 is a 16:9 display, as you can confirm by the simple maths of 1920 / 16 * 9 = 1080, this old Apple Cinema Display see http://support.apple.com/kb/SP502 however has a resolution of 1920x1200 which is a 16:10 aspect ratio as confirmed by 1920 / 16 * 10 = 1200

The current MacBook Pro range are still 16:10, the current MacBook Air range are 16:9 as is the current iMac.

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