Image displaying method, image displaying device, and contrast-adjusting circuit for use therewith
AssigneeHitachi, Ltd.
InventorsHiroshi AOKI, Ryo HASEGAWA
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Abstract
A system provides an image displaying technique that provides stable high contrast even in an area having high brightness. Based on information about an average brightness level of a digital luminance signal, black-correction processing which decreases a brightness level by offsetting the brightness level to the minus side, and increase processing which increases a contrast gain within a dynamic range, are performed for an analog luminance signal or a digital luminance signal, enabling improvement in contrast even where brightness is intense.
Claims24
An image display apparatus using a fixed pixel device for displaying an image based on a video signal, comprising:
- a black correction processor which performs black correction processing of the video signal using average luminance level information of the video signal;
- a contrast controller which controls a contrast of the video signal according to the amount of the black correction of the video signal by the black correction processor;
- and
- a controller,
- wherein the controller has a control characteristic of the amount of the black correction with respect to the average luminance level information;
- a rate of change in a first luminance range of the control characteristic that starts at the average luminance level at which the black correction is started is larger than the rate of change in a second luminance range that is higher than the first luminance range;
- and
- the black correction processor is controlled using the control characteristic.
An image display apparatus using a fixed pixel device for displaying an image based on a video signal comprising:
- a black correction processor which performs black correction processing for the video signal using average luminance level information of the video signal;
- a contrast controller which controls a contrast of the video signal according to the amount of black correction of the video signal by the black correction processor;
- and
- a controller,
- wherein the controller controls the black correction processor such that, when the amount of black correction of a first average luminance information within a first luminance range starting from average luminance level information at which the black correction is started is designated as a first amount of black correction;
- the amount of black correction for a second average luminance information that is within the first luminance range and is higher than the first average luminance information is designated as a second amount of black correction;
- the amount of black correction for a third average luminance information that is within a second luminance range higher than the first luminance range is designated as a third amount of black correction;
- and the amount of black correction for a fourth average luminance information that is within the second luminance range and is higher than the third average luminance information is designated as a fourth amount of black correction, a rate of change from the first amount of black correction to the second amount of black correction becomes larger than the rate of change from the third amount of black correction to the fourth amount of black correction.
Dependencies are inferred from the claim text.