Image processing apparatus, method of setting tonal gradation conversion characteristics, and computer program
AssigneeCanon Kabushiki Kaisha
InventorHitoshi Inoue
Life of this patent
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Abstract
Four test patterns are concurrently displayed on a display of a computer. The test patterns include respective backgrounds and contrast areas. The test patterns, different from each other in pixel value, have identically shaped contrast areas. The contrast between the background and the contrast area remains unchanged from test pattern to test pattern. The contrast areas are adjusted in contrast with the pixel value of the background fixed until the test patterns look the same.
Claims15
A method for processing images to adjust for tonal degradation characteristics for a display device, the method comprising:
- receiving a plurality of test pattern images;
- varying a gradient of one of the plurality of test pattern images to adjust its contrast;
- automatically varying gradients of other non-selected test pattern images to adjust their contrasts, wherein said variation of gradients is equally shared among the non-selected test pattern images;
- repeating the varying and automatic varying steps until all test pattern images meet a predefined criteria;
- and
- generating a LUT (look-up table) associated with the plurality of test pattern images based on determined variation in gradients.
An apparatus for processing an image, comprising:
- an image generating unit for providing a plurality of types of pattern images;
- a tonal gradation conversion unit for using a lookup table to convert one or more of the plurality of pattern images into an output signal;
- a display unit for converting the output signal from the tonal gradation conversion unit into a luminance value to be displayed thereon;
- an input unit for inputting information relating to a pixel value of a background area of the pattern image and/or an amount of change in contrast of the pattern image;
- a control unit for controlling display of the pattern image through the tonal gradation transportation unit, or for controlling display of the pattern image with the lookup table modified;
- a selecting unit for selecting the pattern image presented on the display unit by inputting a confirmation signal;
- and
- a calculating unit for calculating the lookup table from the pixel value of the background of the selected pattern image and the contrast of the selected pattern image.
A method of setting tonal gradation conversion characteristics applied to an image in an image processing apparatus that processes the image displayed on a display unit, the method comprising:
- an input step for selecting the image or a portion thereof, wherein the selected image or portion has a position and contrast associated with said position;
- a modification step for modifying the contrast of the displayed image;
- and
- a setting step for setting tonal gradation conversion characteristics on the image displayed on the display unit.
A computer program for an image processing apparatus for setting tonal gradation conversion characteristics, the computer program comprising program codes for executing:
- an input step for inputting a position in the image displayed on the display unit and a contrast at the position with the position and the contrast associated with each other;
- a modification step for modifying the contrast of the displayed image in accordance with the input information input in the input step;
- and
- a setting step for setting tonal gradation conversion characteristics on the image displayed on the display unit in accordance with the input information.
Dependencies are inferred from the claim text.