Television – Basic receiver with additional function – Multimode
Reexamination Certificate
1998-08-07
2001-05-08
Lee, Michael (Department: 2714)
Television
Basic receiver with additional function
Multimode
C348S556000, C348S558000, C348S445000
Reexamination Certificate
active
06229574
ABSTRACT:
BACKGROUND OF INVENTION
The present invention is related to a converter outputting appropriate screen resolutions according to different aspect ratios, and more particularly for a digital television system.
In the United States, the digital television (TV) standard allows many types of video image formats, with different screen resolutions of 480×640, 480×704, 720×1280, 1080×1920. Thus, a digital TV system must be capable of processing a variety of image sizes, especially because image formats may constantly change, even for the same channel. Additionally, each image size may have different aspect ratios of either 4:3 or 16:9. If the input aspect ratio is 4:3 and the display screen aspect ratio is 16:9, the image may be shown in either 4:3 or 16:9 aspect ratios.
FIG. 1
shows a system for converting the 4:3 input aspect ratio to a 16:9 display aspect ratio. Such system includes a format detector
10
, a converters
12
consisting of a 640:854 converter
120
, a 704:854 converter
122
, a 720:854 converter
124
, a 768:854 converter
126
, and a multiplexer (MUX)
14
. In operation, the format detector
10
receives input image with 4:3 aspect ratio and detects the image size. According to the detected size, the format detector
10
generates an output signal selecting the appropriate converter. The MUX
14
receives the output signal of the format detector
10
and output an image with 16:9 aspect ratio through converters
120
,
122
,
124
,
126
.
Generally, an image with 4:3 aspect ratio has 480 scanning lines with any one of the image sizes from 480×640, 480×704, 480×720 and 480×768. However, an image with a 6:9 aspect ratio has an image size of 480×854. Thus, depending on the input image size, one of converters
120
,
122
,
124
, or
126
will be used to convert an image with a 4:3 aspect ratio to an image with 16:9 aspect ratio.
According to the past aspect ratio converting systems for a digital TV, different converters were used to convert each different image size. However, converters are difficult to manufacture and more importantly, it is difficult to output an image size of exactly 480×854 for 16:9 aspect ratio.
OBJECTIVES OF THE INVENTION
Thus, to solve the above mentioned problem, an object of the present invention is to employ simple converters to accurately convert from one aspect ratio to another.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objects and advantages of the invention may be realized and attained as particularly pointed out in the appended claims.
REFERENCES:
patent: 5365276 (1994-11-01), Imai et al.
patent: 5548340 (1996-08-01), Bertram
patent: 5943097 (1999-08-01), Horii
patent: 5973748 (1999-10-01), Horiguchi et al.
Lee Michael
LG Electronics Inc.
LandOfFree
Screen ratio converter for digital TV does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Screen ratio converter for digital TV, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Screen ratio converter for digital TV will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2439617