Display device, method for controlling display device, control program, and recording medium

Patent metadata

Field	Value
Publication number	US-10237525-B2
Application number	US-201615753079-A
Country	US
Kind code	B2
Filing date	Dec 20, 2016
Priority date	Dec 25, 2015
Publication date	Mar 19, 2019
Grant date	Mar 19, 2019

Abstract

A luminance indicated by an HDR signal is appropriately displayed. A first image processing unit ( 22 ) converts, in accordance with a maximum luminance level indicated by an HDR signal input to the first image processing unit ( 22 ), a gradation performance indicated by the HDR signal into a prescribed gradation performance according to a display panel ( 10 ), and a panel control unit ( 27 ) converts, in accordance with the maximum luminance level indicated by the HDR signal and a maximum luminance displayable by the display panel ( 10 ), a gradation value indicated by the HDR signal into a gradation value displayable by the display panel ( 10 ).

First claim

The invention claimed is:

1. A display device configured to display an image indicated by an HDR signal and an image indicated by an SDR signal, the display device comprising:
a display panel;
a panel control unit configured to control the display panel;
a first image processing unit configured to perform gradation performance conversion of converting, in accordance with a maximum luminance level indicated by the HDR signal input to the first image processing unit, a gradation performance indicated by the HDR signal into a prescribed gradation performance according to the display panel; and
a superimposed image generation unit including a gain adjustment unit configured to change a gradation level of a superimposition target image depending on whether an input signal is the HDR signal or the SDR signal, wherein
the panel control unit is configured to perform gradation value conversion of converting, in accordance with the maximum luminance level indicated by the HDR signal and a maximum luminance displayable by the display panel, a gradation value indicated by an HDR signal after the gradation performance indicated by the HDR signal is converted into a gradation value displayable by the display panel, and
the superimposed image generation unit is configured to superimpose the superimposition target image on an image indicated by the HDR signal after the gradation performance conversion by the first image processing unit.

2. The display device according to claim 1 , wherein
the panel control unit has a prescribed luminance threshold value lower than the maximum luminance displayable by the display panel, and
a luminance lower than or equal to the luminance threshold value is converted into a luminance denoted by the gradation value indicated by the HDR signal.

3. The display device according to claim 1 , wherein
the first image processing unit is configured to execute the gradation performance conversion by performing a prescribed computation or by referring to a look-up table.

4. A television set comprising:
the display device according to claim 1 .

5. A display device configured to display an image indicated by an HDR signal and an image indicated by an SDR signal, the display device comprising:
a display panel;
a panel control unit configured to control the display panel;
a first image processing unit configured to perform gradation performance conversion of converting, in accordance with a maximum luminance level indicated by the HDR signal input to the first image processing unit, a gradation performance indicated by the HDR signal into a prescribed gradation performance according to the display panel;
an image composition unit; and
a second image processing unit which is different from the first image processing unit, wherein
the panel control unit is configured to perform gradation value conversion of converting, in accordance with the maximum luminance level indicated by the HDR signal and a maximum luminance displayable by the display panel, a gradation value indicated by an HDR signal after the gradation performance indicated by the HDR signal is converted into a gradation value displayable by the display panel,
the image composition unit is configured to combine image signals output from the first image processing unit and the second image processing unit to obtain a combined image signal and output the combined image signal to the panel control unit, and
the second image processing unit is configured to perform inverse conversion of the gradation value conversion on the SDR signal which is input.

6. A display device configured to display an image indicated by an HDR signal, the display device comprising:
a display panel;
a panel control unit configured to control the display panel; and
a storage unit configured to store a plurality of patterns of tone maps denoting a correspondence relationship between a gradation value indicated by the HDR signal and a gradation value displayable by the display panel, wherein
the panel control unit is configured to perform gradation value conversion of converting, in accordance with a maximum luminance level indicated by an inputted HDR signal and a maximum luminance displayable by the display panel, the gradation value indicated by the HDR signal after a gradation performance indicated by the inputted HDR signal is converted into the gradation value displayable by the display panel, and
the panel control unit is configured to perform the gradation value conversion with reference to a tone map selected by a user.

7. The display device according to claim 6 , further comprising:
a display control unit configured to display a user interface with which a user selects the tone map, wherein
the user interface is configured to receive a selection by a user via a slide bar or a radio button, and
the display control unit is configured to display the user interface when a signal to be displayed is the HDR signal or to change a display form of the user interface depending on whether or not the signal to be displayed is the HDR signal.

8. The display device according to claim 6 , wherein the tone map shows, in the display panel,
a luminance denoted by the gradation value indicated by the HDR signal,
a luminance denoted by the gradation value indicated by the HDR signal up to a luminance displayable by the display panel, or
a luminance denoted by the gradation value indicated by the HDR signal up to a prescribed threshold value and a luminance denoted by the gradation value appropriately above the threshold value.

9. A display device configured to display an image indicated by an HDR signal and an image indicated by an SDR signal, the display device comprising:
a display panel;
a panel control unit configured to control the display panel;
a plurality of image processing units;
an image composition unit; and
a storage unit configured to store a plurality of patterns of tone maps denoting a correspondence relationship between a gradation value indicated by the HDR signal and a gradation value displayable by the display panel, wherein
the image composition unit is configured to combine image signals output from the plurality of image processing units to obtain a combined image signal and output the combined image signal to the panel control unit,
an image processing unit of the plurality of image processing units which receives the HDR signal converts a gradation performance indicated by the HDR signal into a prescribed gradation performance according to the display panel and converts the prescribed gradation performance into an SDR signal, and
the panel control unit is configured to perform gradation value conversion with reference to a tone map selected by a user.

10. A display device configured to display an image indicated by an HDR signal and an image indicated by an SDR signal, the display device comprising:
a display panel;
a panel control unit configured to control the display panel;
a plurality of image processing units;
an image composition unit; and
a superimposed image generation unit including a gain adjustment unit configured to change a gradation level of a superimposition target image depending on whether an input signal is the HDR signal or the SDR signal, wherein
the image composition unit is configured to combine image signals output from the plurality of image processing units to obtain a combined image signal and output the combined image signal to the panel control unit,
an image processing unit of the plurality of image processing units which receives the HDR signal converts a gradation performance indicated by the HDR signal into a prescribed gradation performance according to the display panel and convert

Assignees

• Sharp Kk

Inventors

• Kanda Takashi
• Hasegawa Makoto
• Shiraya Yoji
• Ichikawa Shingo
• Hirata Koichi
• Hattori Yuusuke

Classifications

• H04N5/202 Primary

  Gamma control (circuits for controlling camera response irrespective of the scene brightness H04N23/82) · CPC title

• H04N5/66

  Transforming electric information into light information (scanning details H04N3/00) · CPC title

• G09G2320/0271

  Adjustment of the gradation levels within the range of the gradation scale, e.g. by redistribution or clipping · CPC title

• H04N7/01

  Conversion of standards {, e.g. involving analogue television standards or digital television standards processed at pixel level} · CPC title

• G09G5/10

  Intensity circuits · CPC title