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Motorola patent for automatic HD zoom mode "Ratio Mismatch"

My friends Phillips 50" Plasma TV does this cool thing where the Zoom mode can be set to a completely automatic mode. The Motorola Cable box outputs 720P for HD and 480I for SD. What's really cool about this TV is that the Zoom is animated and works by itself. Say you are watching something on ABC HD and a commercial comes on which is 4:3 on the 16:9 TV. After about 8 seconds or so the TV zooms the image to fill the screen in a gradual animation. It's pretty neat to watch. The second the channel broadcasts a full 16:9 image, the TV animates the picture scaling into correct pixel mapping.

Well unfortunately my Samsung HP-T4254 does not have this really cool trick zoom. I would have to manually get my Samsung TV remote and cycle through the various zoom options myself. Well searching the internet for some kind of outboard scaler led me to this patent filed by Motorola Connected Home Solutions of Horsham, PA. So perhaps in the future we'll see an easy, simplified way to enjoy full screen content without having to mess with the TV's zoom features. I'd love to see this auto-zoom feature built right into the Cable box in a future firmware update.

Full patent details here:
»www.freepatentsonline.co ··· 465.html

Summery:

Today broadcast video content is available in both a 4:3 ratio and 16:9 ratio formats. Typically, standard definition ("SD") broadcast video is sent in 4:3 and high definition ("HD") broadcast video is sent in 16:9. However, sometimes television broadcasters send HD video signals containing programs that were originally filmed in the 4:3 format ("Ratio Mismatch"). In this instance, the HD broadcaster must add vertical bars ("Pillar Bars") to the left and right sides of the picture to fill the entire 16:9 HD display area. These Pillar Bars are typically black in color, but also may be gray, or some other color or graphic.

[0003] In the case of a Ratio Mismatch where 16:9 content is sent in a 4:3 video stream, horizontal Pilar Bars are added to the top and bottom of the picture to fill the entire 4:3 display area. Horizontal Pillar Bars are also commonly referred to as "Letterbox Bars". As used herein the term "Pillar Bars" is used with reference to both vertical (left and right) bars and horizontal (top and bottom) bars.

[0004] To compensate for the above-described Ratio Mismatch, 16:9 HD televisions/displays and set top boxes typically have a manual "Zoom" function. The Zoom function is usually implemented via a button on an associated remote control to (i) stretch the image horizontally to remove the Pillar Bars thereby compromising the aspect ratio, or (ii) stretch the image both horizontally and vertically thereby filling the display and preserving aspect ratio, while sacrificing a portion of the top and bottom of the image. (The Zoom feature can also prevent uneven display degradation on plasma monitors.) This manual Zoom process is totally controlled by the end user and can be imprecise, inconsistent, and time consuming because the end user is required to press a button(s) on the remote control and step/cycle through Zoom states. Further, when the video content changes ratio (the Pillar Bars disappear or change size, for example), the end user will again have to re-adjust the Zoom, either "in" or "out" manually. In addition, if the video content changes ratio when the end user is performing their manual Zoom, the end user will become highly frustrated, as the end user attempts to Zoom to compensate for a ratio which has since passed. An end user's only other option is to select a static zoom setting, which may under or over Zoom depending on the Ratio Mismatched video content size.

[0005] Thus, what is needed is a system and method which provides a more consistent and efficient process for zooming "in" and "out" a video content stream to adjust for Ratio Mismatches.