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US 12,039,956 B2Granted
Semiconductor device for detecting visibility of displayed OSD characters
AssigneeRohm Co., Ltd.
InventorHiroharu Endo
Life of this patent
Estimating the term…
Abstract
A video input interface receives video data. An OSD circuit draws an on screen display (OSD) character on the video data. The visibility detector checks whether the visibility of the OSD character is good or poor. A determination criterion for the visibility dynamically changes in a manner that depends on a background of the OSD character.
Claims11
A semiconductor device comprising:
- a video input interface structured to receive video data;
- an on screen display (OSD) circuit structured to draw an OSD character on a target region of the video data;
- and
- a visibility detector structured to check whether visibility of the OSD character is good or poor,
- wherein the visibility detector determines whether the visibility is good or poor for each of a plurality of pixels lying within the target region, and
- wherein when the number of pixels having poor visibility exceeds a pixel count threshold p, the visibility of the OSD character is determined to be poor,
- wherein the visibility detector is structured to, for each of a plurality of background pixels included in the target region, calculate color difference between a reference color based on the color of the OSD character and a background color which is a pixel value of each background pixel, to count the number of background pixels having the color difference which is smaller than a threshold T, and to determine the visibility of the OSD character is poor when the counted number of background pixels is larger than the pixel count threshold p, and
- wherein the threshold T for each of the background pixels is determined according to the pixel value of the background pixel.
5 more elements
A semiconductor device comprising:
- a video input interface structured to receive video data;
- an on screen display (OSD) circuit structured to draw an OSD character on a target region of the video data;
- and
- a visibility detector structured to check whether visibility of the OSD character is good or poor, wherein
- wherein the visibility detector determines whether the visibility is good or poor for each of a plurality of pixels lying within the target region,
- wherein when the number of pixels having poor visibility exceeds a pixel count threshold p, the visibility of the OSD character is determined to be poor,
- wherein the visibility detector is structured to, for each of a plurality of background pixels included in the target region, calculate color difference between a reference color based on the color of the OSD character and a background color which is a pixel value of each background pixel, to count the number of background pixels having the color difference which is smaller than a threshold T, and to determine the visibility of the OSD character is poor when the counted number of background pixels is larger than the pixel count threshold p, and
- wherein the threshold T for each of the background pixels is determined according to the pixel value of the background pixel.
5 more elements
A semiconductor device comprising:
- a video input interface structured to receive video data;
- an on screen display (OSD) circuit structured to draw an OSD character on a target region of the video data;
- and
- a visibility detector structured to check whether visibility of the OSD character is good or poor,
- wherein the visibility detector determines whether the visibility is good or poor for each of a plurality of pixels lying within the target region, and
- wherein when the number of pixels having poor visibility exceeds a pixel count threshold p, the visibility of the OSD character is determined to be poor,
- wherein the visibility detector is structured to, for each of a plurality of background pixels included in the target region, calculate color difference between a reference color based on the color of the OSD character and a background color which is a pixel value of each background pixel, to count the number of background pixels having the color difference which is smaller than a threshold T, and to determine the visibility of the OSD character is poor when the counted number of background pixels is larger than the pixel count threshold p,
- wherein the threshold T for each of the background pixels is determined according to the pixel value of the background pixel, and
- wherein the pixel count threshold p is larger as the color of the background pixel is close to black.
6 more elements
A semiconductor device comprising:
- a video input interface structured to receive video data;
- an on screen display (OSD) circuit structured to draw an OSD character on a target region of the video data;
- and
- a visibility detector structured to check whether visibility of the OSD character is good or poor,
- wherein the visibility detector determines whether the visibility is good or poor for each of a plurality of pixels lying within the target region, and
- wherein when the number of pixels having poor visibility exceeds a pixel count threshold p, the visibility of the OSD character is determined to be poor,
- wherein the visibility detector is structured to, for each of a plurality of background pixels included in the target region, calculate color difference between a reference color based on the color of the OSD character and a background color which is a pixel value of each background pixel, to count the number of background pixels having the color difference which is smaller than a threshold T, and to determine the visibility of the OSD character is poor when the counted number of background pixels is larger than the pixel count threshold p,
- wherein the threshold T for each of the background pixels is determined according to the pixel value of the background pixel, and
- wherein the pixel count threshold p is larger as the brightness or luminance of the background pixel is lower.
6 more elements
Dependencies are inferred from the claim text.