Scene adaptive power control apparatus and method thereof

A scene adaptive power control apparatus which uses first, second, third input images as consecutive input images and controls a power level of a light source used in displaying the third input image, the apparatus comprising:

• a histogram analysis unit to generate and analyze a histogram of the second input image and detect a first maximum brightness value that is the greatest brightness value of the second input image;
• a determination unit to determine whether “brightness-values-likely-to-be-clipped” (BVLC) are concentrated on a certain region of a scene of the histogram of the second input image displayed;
• a calculation unit to calculate one of a mean brightness value and a median brightness value of the BVLC if the BVLC are concentrated on the certain region;
• a second maximum brightness value determination unit to determine a second maximum brightness value from the first maximum brightness value based on one of the mean brightness value and the median brightness value, a first threshold predetermined frequency value, and a second threshold;
• a generation unit to generate a power control signal to control the power level of the light source based on a value obtained by dividing the second maximum brightness value by the first maximum brightness value;
• an adjustment unit to adjust the power control signal based on brightness values of the second input image that are increased in inverse proportion to the power level of the light source reduced by the power control signal, and based on a maximum brightness value of the display device displaying the first to third input images;
• and
• a compensation unit to increase a brightness of the third input image in inverse proportion to the power level of the light source reduced by the adjusted power control signal.

A scene adaptive power control method of a scene adaptive power control apparatus which uses first, second and third input images as consecutive input images and controls a power level of a light source used in displaying the third input image, the method comprising:

• generating and analyzing a histogram of the second input image and detecting a first maximum brightness value which is the greatest brightness value of the second input image;
• detecting brightness values matching a first threshold predetermined frequency value from the generated histogram and determining the greatest value of the detected brightness values as a second maximum brightness value;
• generating a power control signal based on a value obtained by dividing the second maximum brightness value by the first maximum brightness value, the power control signal controlling the power level of the light source;
• and
• increasing a brightness of the third input image in inverse proportion to the power level of the light source reduced by the power control signal.

A power control method of a scene adaptive power control apparatus which uses first, second, third input images as consecutive input images and controls a power level of a light source used in displaying the third input image, the method comprising:

• generating and analyzing a histogram of the second input image and detecting a first maximum brightness value that is the greatest brightness value of the second input image;
• determining whether “brightness-values-likely-to-be-clipped” (BVLC) are concentrated on a certain region of a scene of the histogram of the second input image displayed;
• if the BVLC are concentrated on the certain region, calculating one of a mean brightness value and a median brightness value of the BVLC;
• determining a second maximum brightness value from the first maximum brightness value based on one of the mean brightness value and the median brightness value, a first threshold predetermined frequency value, and a second threshold;
• generating a power control signal based on a value obtained by dividing the second maximum brightness value by the first maximum brightness value, the power control signal controlling the power level of the light source;
• adjusting the power control signal based on brightness values of the second input image that are increased in inverse proportion to the power level of the light source reduced by the power control signal, and based on a maximum brightness value of the display device displaying the first to third input images;
• and
• increasing a brightness of the third input image in inverse proportion to the power level of the light source reduced by the adjusted power control signal.

A power control display device comprising:

• a histogram analysis unit to generate a histogram of a first input image and to detect a first maximum brightness value based on the histogram;
• a determination unit to determine brightness values that match a first threshold frequency value in the generated histogram and to determine the greatest value of the determined brightness values as a second maximum brightness value;
• a generation unit to generate a power control signal to change the power level of a light source of the display based on a combination of the second maximum brightness value and the first maximum brightness value;
• and
• a compensation unit to change a brightness of a second input image in inverse proportion to the change of the power level of the light source.

A method of controlling power of a display comprising:

• generating a histogram of a first input image to detect a first maximum brightness value based on the histogram;
• determining brightness values matching a first threshold frequency value in the generated histogram and determining the greatest value of the determined brightness values as a second maximum brightness;
• generating a power control signal to change the power level of a light source of the display based on a combination of the second maximum brightness value and the first maximum brightness value;
• and
• changing a brightness of a second input image in inverse proportion to the change of the power level of the light source.

A power control display device comprising:

• a histogram analysis unit to generate a histogram of a first input image and to detect a first maximum brightness value based on the histogram;
• a determination unit to determine whether “brightness-values-likely-to-be-clipped” (BVLC) are concentrated on a certain region of the histogram of the first input image displayed;
• a calculation unit to calculate one of a mean brightness value and a median brightness value of the BVLC if the BVLC are concentrated on the certain region;
• a second determination unit to determine a second maximum brightness value from the first maximum brightness value based on one of the mean brightness value and the median brightness value, a first threshold, and a second threshold;
• a generation unit to generate a power control signal to change the power level of a light source of the display based on a combination of the second maximum brightness value and the first maximum brightness value;
• and
• a compensation unit to change a brightness of a second input image in inverse proportion to the change of the power level of the light source.

A method of controlling power of a display comprising:

• generating a histogram of a first input image and detecting a first maximum brightness value based on the histogram;
• determining whether “brightness-values-likely-to-be-clipped” (BVLC) are concentrated on a certain region of the histogram of the first input image displayed;
• calculating one of a mean brightness value and a median brightness value of the BVLC if the BVLC are concentrated on the certain region;
• determining a second maximum brightness value from the first maximum brightness value based on one of the mean brightness value and the median brightness value, a first threshold, and a second threshold;
• generating a power control signal to change the power level of a light source of the display based on a combination of the second maximum brightness value and the first maximum brightness value;
• and
• changing a brightness of a second input image in inverse proportion to the change of the power level of the light source controlled by the power control signal.

A power control display device which uses first, second and third input images as consecutive input images and controls a power level of a light source used in displaying the third input image, the device comprising:

• a histogram analysis unit to determine a first maximum brightness value of the second input image;
• a determination unit to determine a second maximum brightness value by reducing the first maximum brightness value;
• a generation unit that uses the second input image to calculate a power control signal based on a combination of the first and second maximum brightness values;
• a power unit to apply the power control signal to lower the power level of the light source;
• and
• a compensation unit to increase the brightness value of the third input image in inverse proportion to the lowered power level of the light source.

A power control display method which uses first, second and third input images as consecutive input images and controls a power level of a light source used in displaying the third input image, the method comprising:

• determining a first maximum brightness value of the second input image;
• determining a second maximum brightness value by reducing the first maximum brightness value;
• using the second input image to calculate a power control signal based on a combination of the first and second maximum brightness values;
• applying the power control signal to lower the power level of the light;
• and
• increasing the brightness value of the third input image in inverse proportion to the lowered power level.

A scene adaptive power control device to control a power level of a light source used to display a final input image of a plurality of input images, the device comprising:

• a histogram analysis unit to output a first maximum brightness value of the plurality of input images;
• a brightness analysis unit to output a second maximum brightness value of the plurality of input images;
• a generation unit to generate a power control signal to control the power level of the light source based on a value obtained by dividing a second maximum brightness value by the first maximum brightness value;
• and
• a compensation unit to decrease the power level of the light source and increase a brightness of the final input image based on the power control signal generated by the generation unit.

A method of controlling a power level of a light source of a display, the method comprising:

• outputting a first maximum brightness value of a plurality of input images;
• outputting a second maximum brightness value of the plurality of input images;
• generating a power control signal to control the power level of the light source based on a value obtained by dividing a second maximum brightness value by the first maximum brightness value;
• decreasing the power level of the light source;
• and
• increasing a brightness of a final input image of the plurality of input images based on the generated power control signal.