Method of enhancing the visibility of screen images
AssigneeJL Marine Systems, Inc.
InventorsStephen E. du Buis, David Bailey
Life of this patent
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Abstract
A method and system for enhancing the visibility of screen images in a high ambient light condition or environment by processing the object images comprising a first stage to increase the brightness of transmission light from the back-light of an LCD screen and a second stage to further enhance the brightness as well as the contrast of the images to be displayed.
Claims13
An image processing system to improve the clarity of object images to be displayed on a display screen comprising to a micro-controller and circuitry:
- wherein said micro-controller and circuitry processes said object images by image analysis, transformation calculation and image transformation to enhance the clarity of object images to be displayed as corresponding display images;
- and
- wherein said image analysis comprises the derivation of image characteristics of the object images including:
- image grey scale values including brightness, perceived brightness and luminance;
- image grey scale frequency histogram;
- image average brightness;
- image range of brightness;
- wherein said range of brightness is derived using a threshold of range values calculated from pixels occurring a predetermined minimum number of times in the object image and dividing the pixels into at least two groups of greater brightness than the image average brightness and those of lesser brightness then using the average brightness of each of said two groups as the minimum and maximum values and
- wherein said range of brightness is calculated as:
- accumMin=0, countMin=0, accumMax=0, countMax=0
- for j=0 to imageWidth {
- for k=0 to imageHeight
- if brightness[j,k]<averageBrightness then
- accumMin=accumMin+brightness[j,k]
- countMin=countMin+1
- else if brightness[j,k]>averageBrightness then
- accumMax=accumMax+brightness[j,k]
- countMax=countMax+1}
- if countMax>0 and countMin>0 then
- result=accumMax/countMax−accumMin/countMin else
- result=0.
An image processing system to improve the clarity of object images to be displayed on a display screen comprising a micro-controller and circuitry:
- wherein said micro-controller and circuitry includes means to process said object images by image analysis, transformation calculation and image transformation to enhance the clarity of object images to be displayed as corresponding display images;
- and
- wherein said image analysis comprises the derivation of image characteristics of the object images including:
- image grey scale values including brightness, perceived brightness and luminance;
- image grey scale frequency histogram;
- image average brightness;
- image range of brightness;
- and
- wherein said image transformation utilizing image analysis and transformation calculations comprises:
- effectFactor=effectIntensity*(0.000075−(rangeOfBrightness/255.0)*0.00004);
- brightnessFactor=((255.0−rangeOfBrightness)/191.0+3.0−averageBrightness/73.0)/255.0
- saturationFactor=(averageBrightness/63.0)/(rangeOfBrightness/47.0)
- if (saturationFactor>0.9) saturationFactor=0.9
- for j=0 to imageWidth {
- for k=0 to imageHeight {
- R=pixel[j,k]red
- G=pixel[j,k]green
- B=pixel[j,k]blue
- factor0=brightnessTransformation[brightness[j,k]]
- factor1=factor0×brightnessFactor
- factor2=|factor0−brightness[j,k]|*effectFactor
- factor3=1.0−factor2
- adjustedR=factor2×(factor1×R+R−(G+B)×saturationFactor)+factor3×R
- adjustedG=factor2×(factor1×G+G−(B+R)×saturationFactor)+factor3×G
- adjustedB=factor2×((factor1×B+B−(R+G)×saturationFactor)+factor3×B
- if (adjustedR>255.0) adjustedR=255.0 else if (adjustedR<0.0) adjustedR=0.0
- if (adjustedG>255.0) adjustedG=255.0 else if (adjustedG<0.0) adjustedG=0.0
- if (adjusted B>255.0) adjustedB=255.0 else if (adjustedB<0.0) adjustedB=0.0
- pixel[j,k]red=adjustedR
- pixel[j,k]green=adjustedG
- pixel[j,k]blue=adjustedB}.
Dependencies are inferred from the claim text.