Method and module for processing high dynamic range (hdr) image and display device using the same

An image processing module comprising:

• an electro-optical transfer function (EOTF) processor configured to receive illuminance information sensed by an illuminance sensor to adjust a perceptual quantizer electro-optical transfer function (PQ-EOTF) and to convert gray level information of a first high dynamic range (HDR) image into luminance information of a second HDR image using the adjusted PQ-EOTF;
• a luminance analyzer configured to analyze the luminance information of the second HDR image to calculate a high-luminance rate of occupancy of pixels having a target peak luminance or more of a display device in the second HDR image;
• a luminance mapping unit configured to map the second HDR image to a third HDR image suitable for the display device using a mapping function changed according to the high-luminance rate;
• and
• an opto-electrical transfer function (OETF) processor configured to convert the luminance information of the third HDR image into gray level information of a fourth HDR image using the PQ-OETF and to output the gray level information of the fourth HDR image.

A display device comprising:

• a display panel;
• an image processing module;
• and
• a display panel driver configured to drive the display panel to display a high dynamic range (HDR) image received from the image processing module,
• wherein the image processing module comprises:
• an electro-optical transfer function (EOTF) processor configured to receive illuminance information sensed by an illuminance sensor to adjust a perceptual quantizer electro-optical transfer function (PQ-EOTF) and to convert gray level information of a first HDR image into luminance information of a second HDR image using the adjusted PQ-EOTF;
• a luminance analyzer configured to analyze the luminance information of the second HDR image to calculate a high-luminance rate of occupancy of pixels having target peak luminance or more of the display device in the second HDR image;
• a luminance mapping unit configured to map the second HDR image to a third HDR image suitable for the display device using a mapping function changed according to the high-luminance rate;
• and
• an opto-electrical transfer function (OETF) processor configured to convert the luminance information of the third HDR image into gray level information of a fourth HDR image using the PQ-OETF and to output the gray level information of the fourth HDR image.