Method of, and apparatus for image enhancement taking ambient illuminance into account

An image enhancement apparatus, comprising:

• an original-luminance contrast calculation part calculating an original-luminance contrast which is a luminance contrast with respect to an original-luminance of pixels forming an original image;
• a fade-luminance calculation part calculating a fade-luminance by reflecting a variation of luminance as perceived based on an ambient illuminance into the original-luminance;
• a defade-luminance calculation part calculating a defade-luminance by converting the fade-luminance, which is calculated by the fade-luminance calculation part, to maintain the original-luminance contrast which is calculated by the original-luminance contrast calculation part;
• and
• a display-luminance calculation part calculating a display-luminance by reflecting the variation of luminance as perceived by the ambient illuminance into the defade-luminance calculated by the defade-luminance calculation part.

A method of reducing a fade phenomenon in an image display device, the method comprising:

• inputting a value indicating an ambient illuminance of the display device;
• determining a luminance and a contrast of an image being displayed;
• adjusting the luminance of the image being displayed based on the input ambient illuminance value, the determined luminance and the determined contrast;
• and
• limiting the adjusted luminance to a predetermined range.

A method of reducing a fade phenomenon in an image display device, the method comprising:

• determining an original-luminance contrast, which is a luminance contrast with respect to an original-luminance of pixels forming an original image;
• determining a defade-luminance contrast, which is a luminance contrast with respect to a defade luminance;
• and
• equalizing the defade-luminance contrast and the original-luminance contrast.