Display device and driving method thereof

Abstract

A display device according to an embodiment of the present disclosure applies a global contrast curve that adjusts the brightness of an entire area of ​​an input image, generates a plurality of local contrast curves corresponding to each of a plurality of local areas based on local information of each of a plurality of local areas included in the entire area, applies each local contrast curve to each local area, and can adjust one or more of the noise processing intensity or sharpness intensity of a local output image to which the local contrast curve is applied based on each local information.

Description

Technology Field

[0001] The present disclosure relates to a display device and a method for driving the same. Background Technology

[0002] Digital images are generally composed of three channels of RGB, and SDR (Standard Dynamic Range) images can generally express brightness in the range of 0-255 (8 bits) for each channel.

[0003] However, because the range of brightness that can be expressed in each channel of SDR images is narrow, there are many cases where dark areas are not properly represented or bright areas are not properly represented.

[0004] For example, in the case of images where there is a significant difference in brightness between dark and bright areas, such as photos taken against the light, the contrast balance becomes skewed to one side.

[0005] Consequently, there can be a significant difference between the scene viewed with the naked eye and the SDR image captured from it. In contrast to such SDR images, images expressed with 16-bit or 32-bit per channel are called HDR (High Dynamic Range) images, and HDR images have the advantage of being able to express images more realistically as they possess a wider range of brightness expression.

[0006] However, since general display devices cannot express 16-bit or 32-bit gradation, 16-bit or 32-bit HDR images need to be converted into digital images with a limited dynamic range.

[0007] Tone mapping is used in the process of converting HDR images into SDR or LDR (Low Dynamic Range) images, and it refers to a technique that compresses the brightness range of an HDR image into the brightness range of an SDR or LDR image while enhancing contrast. Prior art literature

[65535] Republic of Korea Published Patent Application No. 10-2010-0033737 (March 31, 2010) The problem to be solved

[0008] The problem to be solved by the present disclosure is to provide clean and sharp image quality by suppressing digital noise generated when performing tone mapping by applying a local contrast curve to a local area.

[0009] The problem to be solved by the present disclosure is to individually control the noise or clarity of each local area based on local information of the local area. means of solving the problem

[0010] A display device according to an embodiment of the present disclosure applies a global contrast curve that adjusts the brightness of an entire area of ​​an input image, generates a plurality of local contrast curves corresponding to each of a plurality of local areas based on local information of each of a plurality of local areas included in the entire area, applies each local contrast curve to each local area, and can adjust one or more of the noise processing intensity or sharpness intensity of a local output image to which the local contrast curve is applied based on each local information.

[0011] A driving method for a display device according to an embodiment of the present disclosure may include the steps of: applying a global contrast curve that controls the brightness of an entire area of ​​an input image; generating a plurality of local contrast curves corresponding to each of a plurality of local areas based on local information of each of a plurality of local areas included in the entire area; applying each local contrast curve to each local area; and controlling one or more of the noise processing intensity or sharpness intensity of a local output image to which the local contrast curve is applied based on each local information. Effects of the invention

[0012] According to an embodiment of the present disclosure, when tone mapping is performed by applying a local contrast curve to a local area, digital noise generated is suppressed, and a clean and clear image quality can be provided.

[0013] Accordingly, the user's viewing immersion can be increased. Brief explanation of the drawing

[0014] FIG. 1 is a block diagram illustrating the configuration of a display device according to one embodiment of the present disclosure. FIG. 2 is a block diagram of a remote control device according to one embodiment of the present disclosure. FIG. 3 shows an example of the actual configuration of a remote control device according to one embodiment of the present disclosure. FIG. 4 shows an example of utilizing a remote control device according to an embodiment of the present disclosure. FIG. 5 is a flowchart illustrating a method of driving a display device according to an embodiment of the present disclosure. FIG. 6 is a drawing showing an example of an HDR-processed image according to an embodiment of the present disclosure. FIG. 7 is a drawing illustrating a detail map of an image shown in FIG. 6 according to an embodiment of the present disclosure. FIG. 8 is a diagram illustrating the application of gain control of a local area according to detail map information according to an embodiment of the present disclosure. FIG. 9 is a drawing illustrating a change in the curvature of a display device according to an embodiment of the present disclosure. FIG. 10 is a drawing illustrating an example of a local contrast curve applied to a local area according to an embodiment of the present disclosure. FIG. 11 is a drawing illustrating an example of a local contrast curve applied per APL according to an embodiment of the present disclosure. FIG. 12 is a drawing illustrating the case where different sharpnesses are applied to the same APL according to an embodiment of the present disclosure. FIG. 13 is a drawing illustrating local contrast curves for each APL according to curvature change and cases where different sharpnesses are applied at the same APL, according to an embodiment of the present disclosure. FIG. 14 is a flowchart illustrating a method for driving a display device according to another embodiment of the present disclosure. FIGS. 15a and FIGS. 15b are drawings illustrating a process of adjusting the noise intensity or sharpness intensity of a local area within the entire area of ​​an original image according to an embodiment of the present disclosure. Figure 16 is a diagram illustrating a pivot table according to the local APL. Figure 17a is a diagram illustrating a lookup table for classifying some areas of a dark image into bright areas according to APL and for adjusting noise or sharpness of each classified bright area. Figure 17b is a diagram illustrating a lookup table for classifying some areas of a bright image into dark areas according to APL and for adjusting noise or sharpness of each classified dark area. FIG. 18 is a drawing illustrating the configuration of a control unit according to one embodiment of the present disclosure. Specific details for implementing the invention

[0015] Hereinafter, embodiments related to the present disclosure will be described in more detail with reference to the drawings. The suffix "bu" for components used in the following description is assigned or used interchangeably solely for the ease of drafting the specification and does not have a distinct meaning or role in itself.

[0016] Terms containing ordinal numbers, such as first, second, etc., may be used to describe various components, but the components are not limited by the terms. The terms are used solely for the purpose of distinguishing one component from another.

[0017] Hereinafter, the display device is described assuming it is a smart TV or the like that supports broadcast reception functions, but the display device may include a smartphone or the like. That is, the display device according to the embodiment of the present disclosure does not necessarily include the components shown in FIG. 1.

[0018] FIG. 1 is a block diagram illustrating the configuration of a display device according to one embodiment of the present disclosure.

[0019] Referring to FIG. 1, the display device (100) may include a broadcast receiver (130), an external device interface unit (135), a storage unit (140), a user input interface unit (150), a control unit (170), a wireless communication unit (173), a display unit (180), an audio output unit (185), and a power supply unit (190).

[0020] The broadcast receiving unit (130) may include a tuner (131), a demodulating unit (132), and a network interface unit (133).

[0021] The tuner (131) can tune to a specific broadcast channel according to a channel tuning command. The tuner (131) can receive a broadcast signal for the tuned specific broadcast channel.

[0022] The demodulator (132) can separate the received broadcast signal into a video signal, an audio signal, and a data signal related to the broadcast program, and can restore the separated video signal, audio signal, and data signal into a form that can be output.

[0023] The network interface unit (133) may provide an interface for connecting the display device (100) to a wired / wireless network including the Internet network. The network interface unit (133) may transmit or receive data to or from other users or other electronic devices through the connected network or another network linked to the connected network.

[0024] The network interface unit (133) can access a specific web page through a connected network or another network linked to the connected network. That is, it can access a specific web page through a network and transmit or receive data with the corresponding server.

[0025] In addition, the network interface unit (133) can receive content or data provided by a content provider or network operator. That is, the network interface unit (133) can receive content such as movies, advertisements, games, VOD, broadcast signals, and related information provided by a content provider or network provider through a network.

[0026] Additionally, the network interface unit (133) can receive firmware update information and update files provided by the network operator, and can transmit data to the internet, content provider, or network operator.

[0027] The network interface unit (133) can select and receive a desired application among the applications that are open to the public through the network.

[0028] The external device interface unit (135) can receive an application or a list of applications within an adjacent external device and transmit it to the control unit (170) or storage unit (140).

[0029] The external device interface unit (135) can provide a connection path between the display device (100) and an external device. The external device interface unit (135) can receive one or more of video and audio output from an external device connected to the display device (100) wirelessly or via a wired connection and transmit them to the control unit (170). The external device interface unit (135) may include a plurality of external input terminals. The plurality of external input terminals may include an RGB terminal, one or more HDMI (High Definition Multimedia Interface) terminals, and a component terminal.

[0030] The video signal of an external device input through the external device interface unit (135) can be output through the display unit (180). The voice signal of an external device input through the external device interface unit (135) can be output through the audio output unit (185).

[0031] The external device that can be connected to the external device interface section (135) may be any one of a set-top box, Blu-ray player, DVD player, game console, soundbar, smartphone, PC, USB memory, or home theater, but this is merely an example.

[0032] In addition, some of the content data stored in the display device (100) can be transmitted to another user or other electronic device selected among other users or other electronic devices that are previously registered in the display device (100).

[0033] The storage unit (140) can store programs for each signal processing and control within the control unit (170), and can store signal-processed video, audio, or data signals.

[0034] Additionally, the storage unit (140) may perform the function of temporarily storing video, audio, or data signals input from the external device interface unit (135) or the network interface unit (133), and may also store information regarding a predetermined image through a channel memory function.

[0035] The storage unit (140) can store an application or a list of applications input from an external device interface unit (135) or a network interface unit (133).

[0036] The display device (100) can play content files (video files, still image files, music files, document files, application files, etc.) stored in the storage unit (140) and provide them to the user.

[0037] The user input interface unit (150) can transmit a signal input by the user to the control unit (170) or transmit a signal from the control unit (170) to the user. For example, the user input interface unit (150) can receive and process control signals such as power on / off, channel selection, and screen setting from the remote control device (200) according to various communication methods such as Bluetooth, Ultra Wideband (WB), ZigBee, Radio Frequency (RF) communication, or Infrared (IR) communication, or process to transmit control signals from the control unit (170) to the remote control device (200).

[0038] Additionally, the user input interface unit (150) can transmit control signals input from local keys (not shown), such as power key, channel key, volume key, and setting value, to the control unit (170).

[0039] The image signal processed by the control unit (170) can be input to the display unit (180) and displayed as an image corresponding to the image signal. Additionally, the image signal processed by the control unit (170) can be input to an external output device through the external device interface unit (135).

[0040] The voice signal processed by the control unit (170) can be output as audio to the audio output unit (185). Additionally, the voice signal processed by the control unit (170) can be input to an external output device through the external device interface unit (135).

[0041] In addition, the control unit (170) can control the overall operation within the display device (100).

[0042] Additionally, the control unit (170) can control the display device (100) by means of a user command or internal program input through the user input interface unit (150), and can connect to a network to allow the user to download an application or a list of applications desired by the user into the display device (100).

[0043] The control unit (170) enables the processed video or audio signal, such as channel information selected by the user, to be output through the display unit (180) or audio output unit (185).

[0044] Additionally, the control unit (170) enables a video signal or audio signal from an external device, such as a camera or camcorder, input through the external device interface unit (135) according to an external device video playback command received through the user input interface unit (150), to be output through the display unit (180) or audio output unit (185).

[0045] Meanwhile, the control unit (170) can control the display unit (180) to display an image, for example, a broadcast image input through the tuner (131), an external input image input through the external device interface unit (135), an image input through the network interface unit, or an image stored in the storage unit (140) can be controlled to be displayed on the display unit (180). In this case, the image displayed on the display unit (180) may be a still image or a video, and may be a 2D image or a 3D image.

[0046] Additionally, the control unit (170) can control the playback of content stored in the display device (100), received broadcast content, or external input content input from the outside, and the content may be in various forms such as broadcast video, external input video, audio file, still image, connected web screen, and document file.

[0047] The wireless communication unit (173) can communicate with an external device via wired or wireless communication. The wireless communication unit (173) can perform short-range communication with an external device. To this end, the wireless communication unit (173) can support short-range communication by using at least one of Bluetooth™, BLE (Bluetooth Low Energy), RFID (Radio Frequency Identification), Infrared Data Association (IrDA), UWB (Ultra Wideband), ZigBee, NFC (Near Field Communication), Wi-Fi (Wireless-Fidelity), Wi-Fi Direct, and Wireless USB (Wireless Universal Serial Bus) technologies. Such wireless communication unit (173) can support wireless communication between a display device (100) and a wireless communication system, between a display device (100) and another display device (100), or between a display device (100) and a network where a display device (100, or an external server) is located, through a wireless area network. The wireless area network may be a wireless personal area network.

[0048] Here, another display device (100) may be a mobile terminal such as a wearable device (e.g., a smartwatch, smart glass, HMD (head mounted display)), or a smartphone that is capable of exchanging (or interacting) data with the display device (100) according to the present invention. A wireless communication unit (173) may detect (or recognize) a wearable device capable of communicating around the display device (100). Furthermore, if the detected wearable device is an authenticated device to communicate with the display device (100) according to the present invention, the control unit (170) may transmit at least a portion of the data processed by the display device (100) to the wearable device through the wireless communication unit (173). Accordingly, the user of the wearable device may use the data processed by the display device (100) through the wearable device.

[0049] The display unit (180) can generate a driving signal by converting the video signal, data signal, OSD signal processed by the control unit (170) or the video signal, data signal, etc. received from the external device interface unit (135) into R, G, and B signals, respectively.

[0050] Meanwhile, since the display device (100) illustrated in FIG. 1 is merely an embodiment of the present disclosure, some of the illustrated components may be integrated, added, or omitted depending on the specifications of the actual implemented display device (100).

[0051] That is, as needed, two or more components may be combined into a single component, or a single component may be subdivided into two or more components. In addition, the function performed in each block is intended to explain the embodiments of the present disclosure, and the specific operation or device does not limit the scope of the rights of the present disclosure.

[0052] According to another embodiment of the present disclosure, the display device (100) may receive and play an image through a network interface unit (133) or an external device interface unit (135) without having a tuner (131) and a demodulator (132), unlike as shown in FIG. 1.

[0053] For example, the display device (100) may be implemented by separating it into a video processing device, such as a set-top box, for receiving broadcast signals or content according to various network services, and a content playback device for playing content input from the video processing device.

[0054] In this case, the method of operation of the display device according to the embodiment of the present disclosure described below may be performed not only by the display device (100) described with reference to FIG. 1, but also by any one of a video processing device such as a separated set-top box, or a content playback device having a display unit (180) and an audio output unit (185).

[0055] Next, with reference to FIGS. 2 and 3, a remote control device according to one embodiment of the present disclosure will be described.

[0056] FIG. 2 is a block diagram of a remote control device according to one embodiment of the present disclosure, and FIG. 3 shows an example of an actual configuration of a remote control device according to one embodiment of the present disclosure.

[0057] First, referring to FIG. 2, the remote control device (200) may include a fingerprint recognition unit (210), a wireless communication unit (220), a user input unit (230), a sensor unit (240), an output unit (250), a power supply unit (260), a storage unit (270), a control unit (280), and a voice acquisition unit (290).

[0058] Referring to FIG. 2, the wireless communication unit (220) transmits and receives signals with any one of the display devices according to the embodiments of the present disclosure described above.

[0059] The remote control device (200) is equipped with an RF module (221) capable of transmitting and receiving signals to and from the display device (100) according to RF communication standards, and may be equipped with an IR module (223) capable of transmitting and receiving signals to and from the display device (100) according to IR communication standards. Additionally, the remote control device (200) may be equipped with a Bluetooth module (225) capable of transmitting and receiving signals to and from the display device (100) according to Bluetooth communication standards. Furthermore, the remote control device (200) may be equipped with an NFC module (227) capable of transmitting and receiving signals to and from the display device (100) according to NFC (Near Field Communication) communication standards, and may be equipped with a WLAN module (229) capable of transmitting and receiving signals to and from the display device (100) according to WLAN (Wireless LAN) communication standards.

[0060] Additionally, the remote control device (200) transmits a signal containing information regarding the movement of the remote control device (200), etc., to the display device (100) through the wireless communication unit (220).

[0061] Meanwhile, the remote control device (200) can receive a signal transmitted by the display device (100) through the RF module (221), and, if necessary, can transmit commands regarding power on / off, channel change, volume change, etc. to the display device (100) through the IR module (223).

[0062] The user input unit (230) may be composed of a keypad, buttons, a touchpad, or a touch screen. The user can input commands related to the display device (100) to the remote control device (200) by operating the user input unit (230). If the user input unit (230) is equipped with a hard key button, the user can input commands related to the display device (100) to the remote control device (200) through a push operation of the hard key button. This will be explained with reference to FIG. 3.

[0063] Referring to FIG. 3, the remote control device (200) may include a plurality of buttons. The plurality of buttons may include a fingerprint recognition button (212), a power button (231), a home button (232), a live button (233), an external input button (234), a volume control button (235), a voice recognition button (236), a channel change button (237), a confirmation button (238), and a back button (239).

[0064] The fingerprint recognition button (212) may be a button for recognizing a user's fingerprint. In one embodiment, the fingerprint recognition button (212) may be capable of a push operation, and may receive a push operation and a fingerprint recognition operation. The power button (231) may be a button for turning the power of the display device (100) on / off. The home button (232) may be a button for moving to the home screen of the display device (100). The live button (233) may be a button for displaying a real-time broadcast program. The external input button (234) may be a button for receiving an external input connected to the display device (100). The volume control button (235) may be a button for adjusting the volume output by the display device (100). The voice recognition button (236) may be a button for receiving the user's voice and recognizing the received voice. The channel change button (237) may be a button for receiving a broadcast signal of a specific broadcast channel. The confirmation button (238) may be a button for selecting a specific function, and the back button (239) may be a button for returning to the previous screen.

[0065] Figure 2 is explained again.

[0066] If the user input unit (230) is equipped with a touchscreen, the user can input commands related to the display device (100) to the remote control device (200) by touching the soft keys on the touchscreen. Additionally, the user input unit (230) may be equipped with various types of input means that the user can operate, such as a scroll key or a jog key, and this embodiment does not limit the scope of the rights of this disclosure.

[0067] The sensor unit (240) may be equipped with a gyroscope sensor (241) or an accelerometer sensor (243), and the gyroscope sensor (241) may sense information regarding the movement of the remote control device (200).

[0068] For example, the gyroscope sensor (241) can sense information regarding the operation of the remote control device (200) based on the x, y, and z axes, and the accelerometer sensor (243) can sense information regarding the movement speed of the remote control device (200). Meanwhile, the remote control device (200) may further be equipped with a distance measuring sensor to sense the distance to the display unit (180) of the display device (100).

[0069] The output unit (250) can output a video or audio signal corresponding to the operation of the user input unit (230) or a signal transmitted from the display device (100). Through the output unit (250), the user can recognize whether the user input unit (230) is operated or whether the display device (100) is controlled.

[0070] For example, the output unit (250) may be equipped with an LED module (251) that lights up when the user input unit (230) is operated or when a signal is transmitted and received with the display device (100) through the wireless communication unit (220), a vibration module (253) that generates vibration, a sound output module (255) that outputs sound, or a display module (257) that outputs video.

[0071] Additionally, the power supply unit (260) supplies power to the remote control device (200), and can reduce power waste by stopping the power supply when the remote control device (200) does not move for a predetermined period of time. The power supply unit (260) can resume power supply when a predetermined key provided in the remote control device (200) is operated.

[0072] The storage unit (270) may store various types of programs, application data, etc., necessary for the control or operation of the remote control device (200). If the remote control device (200) transmits and receives signals wirelessly through the display device (100) and the RF module (221), the remote control device (200) and the display device (100) transmit and receive signals through a predetermined frequency band.

[0073] The control unit (280) of the remote control device (200) can store and refer to information regarding frequency bands, etc., that can wirelessly transmit and receive signals with the display device (100) paired with the remote control device (200) in the storage unit (270).

[0074] The control unit (280) controls all matters related to the control of the remote control device (200). The control unit (280) can transmit a signal corresponding to a predetermined key operation of the user input unit (230) or a signal corresponding to the movement of the remote control device (200) sensed by the sensor unit (240) to the display device (100) through the wireless communication unit (220).

[0075] In addition, the voice acquisition unit (290) of the remote control device (200) can acquire voice.

[0076] The voice acquisition unit (290) may include at least one microphone (291) and may acquire voice through the microphone (291).

[0077] Next, Figure 4 is explained.

[0078] FIG. 4 shows an example of utilizing a remote control device according to an embodiment of the present disclosure.

[0079] FIG. 4(a) illustrates a pointer (205) corresponding to a remote control device (200) being displayed on a display unit (180).

[0080] The user can move or rotate the remote control device (200) up and down, left and right. The pointer (205) displayed on the display part (180) of the display device (100) corresponds to the movement of the remote control device (200). Since the pointer (205) of the remote control device (200) moves and is displayed according to the movement in 3D space as shown in the drawing, it can be named a spatial remote control.

[0081] FIG. 4(b) illustrates that when the user moves the remote control device (200) to the left, the pointer (205) displayed on the display part (180) of the display device (100) also moves to the left in response.

[0082] Information regarding the movement of the remote control device (200) detected through the sensor of the remote control device (200) is transmitted to the display device (100). The display device (100) can calculate the coordinates of the pointer (205) from the information regarding the movement of the remote control device (200). The display device (100) can display the pointer (205) to correspond to the calculated coordinates.

[0083] FIG. 4(c) illustrates a case where, while pressing a specific button within the remote control device (200), the user moves the remote control device (200) away from the display unit (180). By doing so, the selected area within the display unit (180) corresponding to the pointer (205) can be zoomed in and enlarged.

[0084] Conversely, when the user moves the remote control device (200) closer to the display unit (180), the selected area within the display unit (180) corresponding to the pointer (205) can be zoomed out and reduced in size.

[0085] Meanwhile, when the remote control device (200) moves away from the display unit (180), the selected area may be zoomed out, and when the remote control device (200) moves closer to the display unit (180), the selected area may be zoomed in.

[0086] Additionally, when a specific button within the remote control device (200) is pressed, recognition of up-down and left-right movement may be excluded. That is, when the remote control device (200) moves away from or closer to the display unit (180), up-down, left-right movement is not recognized, and only forward-backward movement is recognized. When the specific button within the remote control device (200) is not pressed, only the pointer (205) moves according to the up-down, left-right movement of the remote control device (200).

[0087] Meanwhile, the movement speed or direction of movement of the pointer (205) can correspond to the movement speed or direction of movement of the remote control device (200).

[0088] Meanwhile, the pointer in this specification refers to an object displayed on the display unit (180) in response to the operation of the remote control device (200). Accordingly, the pointer (205) can be an object of various shapes other than the arrow shape shown in the drawing. For example, it may be a concept including a point, a cursor, a prompt, a thick outline, etc. Furthermore, the pointer (205) can be displayed corresponding to either a point on the horizontal axis or a vertical axis on the display unit (180), and it is also possible to display it corresponding to multiple points, such as a line or a surface.

[0089] A display device (100) according to an embodiment may include a control unit (170) that performs tone mapping to adjust the brightness of input image data.

[0090] The display device (100) may include a display unit (180) that displays an image according to output image data whose brightness is adjusted by tone mapping performed by the control unit (170).

[0091] The control unit (170) can generate a base mapping curve for the entire area from the input image data. The control unit (170) can extract local area-specific information for the entire area and generate a local mapping curve for each local area that reflects the local area-specific information. The control unit (170) can perform tone mapping for each local area using the local mapping curve that reflects the local area-specific information. An image based on the output image data for which local mapping has been performed for each local area by the control unit (170) can be displayed on the display unit (180).

[0092] The base mapping curve may include a dynamic contrast curve (dynamic contract curve) for the entire area. The local mapping curve may include a local contrast curve for the corresponding local area.

[0093] The control unit (170) can extract local area-specific information of the entire area and, based on the extracted local area-specific information, generate an adaptive local contrast curve for each local area from the mapping curve of the entire area. The control unit (170) can perform tone mapping for each local area using the adaptive local contrast curve generated for each local area.

[0094] The display unit (180) may be provided as a flat display unit. The display unit (180) may be provided as a curved display unit having curvature. The display unit (180) may be provided as a bendable display unit with a changing curvature.

[0095] When the display unit (180) is provided as a bendable display unit, for example, a request signal for changing the curvature of the display unit (180) may be input from a user. For example, the request signal for changing the curvature input from the user may be input through the user input interface unit (150). The user input interface unit (150) may transmit the input request signal for changing the curvature of the display unit (180) to the control unit (170). The control unit (170) may change the curvature of the display unit (180) according to the user's request signal for changing the curvature.

[0096] For example, the user can transmit a request signal to change the curvature of the display unit (180) through a remote control device (200).

[0097] The display unit (180) is provided to enable continuous curvature changes, and any curvature may be selected to change the curvature. Additionally, the display unit (180) may have its curvature changed by selecting one of a plurality of predetermined curvature steps. For example, the curvature of the display unit (180) may be implemented as a flat plane, a first curvature (1000R), a second curvature (800R), etc.

[0098] According to the display device (100) according to the embodiment, for example, when a user presses a specific button of the remote control device (200), the curvature of the display unit (180) can be implemented to sequentially change to a flat plane, a first curvature, a second curvature, etc.

[0099] In addition, according to the display device (100) according to the embodiment, while the user is pressing a specific button of the remote control device (200), the curvature of the display unit (180) is continuously changed, and the curvature of the display unit (180) at the time when the user stops pressing the specific button may be selected.

[0100] Hereinafter, with reference to FIG. 5, we will further examine the process of performing tone mapping in a display device according to an embodiment.

[0101] FIG. 5 is a flowchart illustrating a method of driving a display device according to an embodiment of the present disclosure.

[0102] The control unit (170) can generate a base mapping curve for the entire area (S501).

[0103] According to the driving method of the display device (100) according to the embodiment, the control unit (170) can generate a base mapping curve for the entire area from the input image data.

[0104] For example, a base mapping curve can be generated through High Dynamic Range (HDR) processing of input image data.

[0105] The base mapping curve generated by the control unit (170) may include a Dynamic Tone Mapping (DTM) curve and a Dynamic Contrast (DC) curve.

[0106] The control unit (170) may receive metadata along with the image data when receiving the image data. The input image data may be an HDR image. The metadata may include information about the input image data. The metadata may include at least one of luminance information of the HDR image, maximum brightness information per scene, and information for identifying that it is an HDR image.

[0107] Additionally, the control unit (170) can calculate a luminance distribution histogram over the entire area of ​​the input image data. The luminance distribution histogram of the HDR image may represent distribution information of the brightness values ​​of each pixel of the HDR image. The control unit (170) can calculate a luminance distribution histogram that is a distribution of the signal levels (e.g., 0 to 1023) of each pixel of the HDR image.

[0108] The control unit (170) can generate a Dynamic Tone Mapping (DTM) curve based on luminance distribution histogram information for the input image data. The DTM curve may refer to a mapping curve in the RGB domain. In the RGB domain, mapping from the input image data to the output image data can be performed according to the generated DTM curve.

[0109] The control unit (170) can generate a DC (Dynamic Contrast) curve. The DC curve may represent a mapping curve in the luminance (Y) domain. In the luminance (Y) domain, mapping from input image data to output image data can be performed in accordance with the generated TC curve.

[0110] Meanwhile, since a method for generating DTM curves and DC curves in the control unit (170) to generate output image data suitable for the characteristics of the display unit (180) for input image data is known, a detailed explanation thereof will be omitted here.

[0111] Next, the control unit (170) can analyze local area-specific information (S503).

[0112] According to the driving method of the display device (100) according to the embodiment, the control unit (170) can extract information for each local area of ​​the entire area. The control unit (170) can extract information for each local area constituting the entire area.

[0113] For example, local area-specific information can be extracted from a detail map generated based on pixel information of the entire area. The detail map may include Average Picture Level (APL) information and sharpness information for each local area.

[0114] Referring to FIGS. 6 and FIGS. 7, we will examine the detail map according to the embodiment.

[0115] FIG. 6 is a drawing showing an example of an HDR-processed image according to an embodiment of the present disclosure, and FIG. 7 is a drawing explaining a detail map of the image shown in FIG. 6 according to an embodiment of the present disclosure.

[0116] FIG. 6 shows an HDR-processed image according to an embodiment, wherein the entire area of ​​the image can be divided into a plurality of local areas.

[0117] Multiple local regions can be divided into an arbitrary number for the entire area, taking into account image processing speed and effect. For example, if the entire area of ​​the image has a resolution of (1920*1080), multiple local regions can be provided in a number of (96*54). This is an example, and the size and number of multiple local regions can be varied as needed.

[0118] Figure 7 shows the detail degree of the entire area of ​​the image illustrated in Figure 6. The detail degree may be the amount of change in luminance values ​​for adjacent pixels within a certain distance. The detail degree of each pixel may refer to the difference (or rate of change) between each pixel and adjacent pixels. A pixel with a large change in color or luminance compared to surrounding pixels may be considered a pixel with a high detail degree.

[0119] For example, a detail map can be extracted by applying a Laplacian filter to the entire area. Detail maps can also be extracted using various other tools or other methods.

[0120] Local area-specific information can be extracted from a detail map generated based on pixel information of the entire area. The detail map may include Average Picture Level (APL) information and sharpness information for each local area.

[0121] APL information for each local area can refer to the brightness level of each local area. Sharpness information for each local area can refer to the detail level of each local area.

[0122] For example, the first region (R1) illustrated in FIGS. 6 and 7 may be determined to be a region with no change in the degree of detail. The first region (R1) illustrated in FIGS. 6 and 7 may be determined to be a region without sharpness.

[0123] Additionally, the second region (R2) and the third region (R3) shown in FIGS. 6 and 7 may be determined to be regions with a change in the degree of detail. The second region (R2) and the third region (R3) shown in FIGS. 6 and 7 may be determined to be regions with sharpness.

[0124] It can be seen that the first region (R1), second region (R2), and third region (R3) shown in FIGS. 6 and 7 have different degrees of APL.

[0125] In this way, the control unit (170) can extract APL information and sharpness information for each local area from the detail map.

[0126] Next, the control unit (170) can apply a local mapping curve for each local area (S505).

[0127] We will examine the process of generating a local mapping curve for each local area in the control unit (170) of the display device (100) according to the embodiment, and applying the generated local mapping curve to the tone mapping of the corresponding local area.

[0128] The display device (100) according to the embodiment of the present disclosure does not perform tone mapping using the same mapping curve for the entire area. The display device (100) according to the embodiment generates a local mapping curve for each local area that reflects information of each local area, and can perform tone mapping for each local area using the corresponding local mapping curve.

[0129] A display device (100) according to an embodiment can generate an adaptive local contrast curve for each local area based on extracted local area information and perform tone mapping for each local area.

[0130] The control unit (170) can generate a local mapping curve that reflects information for each local area. The control unit (170) can generate a local mapping curve for each local area using APL information and sharpness information for each local area.

[0131] For example, each of the first region (R1), second region (R2), and third region (R3) differs from one another in terms of APL and sharpness. That is, the APL values ​​of each region are different, and the sharpness values ​​of each region are different. Accordingly, local mapping curves suitable for each region can be generated differently.

[0132] The control unit (170) can generate a first local mapping curve for a first region (R1) based on the APL information and sharpness information of the first region. The control unit (170) can generate a second local mapping curve for a second region (R2) based on the APL information and sharpness information of the second region. The control unit (170) can generate a third local mapping curve for a third region (R3) based on the APL information and sharpness information of the third region.

[0133] For example, the first region (R1) may be determined to be a region with no change in the degree of detail. That is, the first region (R1) may be determined to be a region without sharpness. The control unit (170) may perform local tone mapping using a base mapping curve generated for the entire region without generating a separate first local mapping curve for the first region (R1).

[0134] The second region (R2) can be determined to be a region with a change in the degree of detail. That is, the second region (R2) can be determined to be a region with sharpness. The control unit (170) can generate a separate second local mapping curve for the second region (R2) and perform local tone mapping for the second region (R2) using the generated second local mapping curve.

[0135] For example, the control unit (170) can generate a second local mapping curve that can enhance brightness and contrast for the second region (R2). The control unit (170) can enhance the brightness and contrast of the local region if the degree of sharpness of the local region is high. The control unit (170) can perform local tone mapping for the second region (R2) by applying the second local mapping curve instead of the DC curve among the base mapping curves generated for the entire region.

[0136] The third region (R3) can be determined as a region with a change in the degree of detail. That is, the third region (R3) can be determined as a region with sharpness. The control unit (170) can generate a separate third local mapping curve for the third region (R3) and perform local tone mapping for the third region (R3) using the generated third local mapping curve.

[0137] For example, the control unit (170) can generate a third local mapping curve that can enhance brightness and contrast for the third region (R3). The control unit (170) can enhance the brightness and contrast of the local region if the degree of sharpness of the local region is high. The control unit (170) can perform local tone mapping for the third region (R3) by applying the third local mapping curve instead of the DC curve among the base mapping curves generated for the entire region.

[0138] The control unit (170) can perform tone mapping for each local area using a local mapping curve that reflects information for each local area.

[0139] According to an embodiment, a local mapping curve can be generated by adding a contrast curve, which reflects information specific to each local area, to a base mapping curve generated for the entire area.

[0140] For example, the local mapping curve for the first region (R1) may include a DTM curve of the base mapping curve generated for the entire region (applied to the RGB domain) and a DC curve of the base mapping curve generated for the entire region (applied to the luminance domain).

[0141] The local mapping curve for the second region (R2) may include a DTM curve of the base mapping curve generated for the entire region (applied to the RGB domain) and a second local mapping curve generated for the second region (applied to the luminance domain).

[0142] The local mapping curve for the third region (R3) may include a DTM curve of the base mapping curve generated for the entire region (applied to the RGB domain) and a third local mapping curve generated for the third region (applied to the luminance domain).

[0143] In this way, according to the display device and driving method according to the embodiment of the present disclosure, the contrast ratio in the local area can be improved by utilizing information in the local area of ​​the image, and the three-dimensionality of the image and user immersion can be improved.

[0144] According to the display device and driving method according to the embodiment of the present disclosure, by utilizing brightness and sharpness information for each region of a local area of ​​an image, the contrast ratio in the local area can be improved, and the three-dimensionality of the image and user immersion can be enhanced.

[0145] According to the display device and driving method according to the embodiment of the present disclosure, by generating an adaptive local contrast curve for each local area based on extracted local area information and performing tone mapping, the contrast ratio in the local area can be improved, and the three-dimensionality of the image and user immersion can be enhanced.

[0146] FIG. 8 is a diagram illustrating the application of gain control of a local area according to detail map information according to an embodiment of the present disclosure.

[0147] The control unit (170) of the display device (100) according to the embodiment can extract sharpness information and APL information for each local area from the detail map and determine the degree of brightness enhancement and the degree of contrast enhancement for the corresponding local area.

[0148] The control unit (170) can determine the degree of brightness enhancement, the degree of contrast enhancement, etc. for each local area by using at least one of the information among the sharpness information and APL information of each local area.

[0149] For example, as illustrated in FIG. 8, the control unit (170) can extract the degree of brightness enhancement and / or contrast enhancement in a local area through calculation of gain according to the degree of sharpness and gain according to the degree of APL in each local area. Through this process, the control unit (170) can detect a local area of ​​interest to be processed for brightness enhancement and / or contrast enhancement.

[0150] Additionally, the control unit (170) can adjust the output gain relative to the input by calculating the gain for the degree of brightness and the gain for the degree of darkness, respectively, for the gain of the detected local region of interest.

[0151] Through this process, the control unit (170) can determine the degree of brightness enhancement and the degree of contrast enhancement for each local area from the sharpness information and APL information in each local area.

[0152] Meanwhile, the display device (100) according to the embodiment described above was described based on the case where the display part (180) is provided in a flat shape.

[0153] According to an embodiment, the display unit (180) may be provided as a curved display unit having a curvature. Additionally, the display unit (180) may be provided as a bendable display unit with a changeable curvature.

[0154] A control unit (180) according to an embodiment can generate a local mapping curve that reflects at least one of the APL information, sharpness information, position information, and curvature information of each local area, and perform tone mapping for each local area when the display unit (180) is provided as a curved display unit or a bendable display unit.

[0155] FIG. 9 is a drawing illustrating a change in the curvature of a display device according to an embodiment of the present disclosure.

[0156] According to an embodiment, a local mapping curve can be generated by adding a contrast curve, which reflects at least one of the APL information, sharpness information, position information, and curvature information of each local area, to a base mapping curve generated for the entire area.

[0157] For example, the display device (100) may be provided as a bendable display device with a changeable curvature, and the curvature of the display part may be changed according to a user request in the form of a flat display part (901), a display part (903) having a first curvature (1000R), and a display part (905) having a second curvature (800R).

[0158] When the display device (100) includes a flat display unit (901), the local mapping curves in the first area (R1), the second area (R2), and the third area (R3) can be determined as described with reference to FIGS. 5 to 8.

[0159] When the display device (100) includes a display portion (903) having a first curvature, the control unit (170) can further enhance the brightness level compared to when provided as a flat display portion (901) for a first region (R1) without sharpness. The control unit (170) can further enhance the brightness level and further enhance the contrast compared to when provided as a flat display portion (901) for a second region (R2) with sharpness. The control unit (170) can further enhance the brightness level and further enhance the contrast compared to when provided as a flat display portion (901) for a third region (R3) with sharpness.

[0160] When provided with a display unit (905) having a second curvature, the control unit (170) can further enhance the brightness level for a first region (R1) without sharpness compared to when provided with a display unit (903) having a first curvature. The control unit (170) can further enhance the brightness level and further enhance the contrast for a second region (R2) with sharpness compared to when provided with a display unit (903) having a first curvature. The control unit (170) can further enhance the brightness level and further enhance the contrast for a third region (R3) with sharpness compared to when provided with a display unit (903) having a first curvature.

[0161] The control unit (170) of the display device (100) according to the embodiment can enhance the brightness and contrast of the local area if the curvature of the local area is large.

[0162] The control unit (170) of the display device (100) according to the embodiment can enhance brightness if the local area has curvature and the local area is located at the center of the entire area. The control unit (170) can enhance contrast if the local area has curvature and the local area is located at the side of the entire area.

[0163] The control unit (170) can generate a first local mapping curve for a first region (R1) based on the APL information, sharpness information, position information, and curvature information of the first region. The control unit (170) can generate a second local mapping curve for a second region (R2) based on the APL information, sharpness information, position information, and curvature information of the second region. The control unit (170) can generate a third local mapping curve for a third region (R3) based on the APL information, sharpness information, position information, and curvature information of the third region.

[0164] The control unit (170) can perform tone mapping for each local area using a local mapping curve that reflects information for each local area.

[0165] Thus, according to the bendable display device and driving method according to the embodiment of the present disclosure, the contrast ratio in the local area can be improved by utilizing information of the local area of ​​the image, and the three-dimensionality of the image and user immersion can be improved.

[0166] According to the bendable display device and driving method according to the embodiment of the present disclosure, by utilizing brightness and sharpness information for each region of a local area of ​​an image, the contrast ratio in the local area can be improved, and the three-dimensionality of the image and user immersion can be enhanced.

[0167] According to the bendable display device and driving method according to the embodiment of the present disclosure, by utilizing brightness, sharpness information, and position information for each region of a local area of ​​an image, the contrast ratio in the local area can be improved, and the three-dimensionality of the image and user immersion can be enhanced.

[0168] According to the bendable display device and driving method according to the embodiment of the present disclosure, the brightness, sharpness information, position information, and curvature information of each local area of ​​the image can be utilized to further enhance the three-dimensionality of the image and user immersion.

[0169] According to the bendable display device and driving method according to the embodiment of the present disclosure, by generating an adaptive local contrast curve for each local area based on extracted local area information and performing tone mapping, the contrast ratio in the local area can be improved, and the three-dimensionality of the image and user immersion can be enhanced.

[0170] When the display unit (180) is provided as a bendable display unit, for example, a request signal for changing the curvature of the display unit (180) may be input from a user. For example, the request signal for changing the curvature input from the user may be input through the user input interface unit (150). The user input interface unit (150) may transmit the input request signal for changing the curvature of the display unit (180) to the control unit (170). The control unit (170) may change the curvature of the display unit (180) according to the user's request signal for changing the curvature. The control unit (170) may adjust the local mapping curve of each local area according to the curvature of the display unit (180).

[0171] FIG. 10 is a drawing illustrating an example of a local area contrast curve applied to a local area according to an embodiment of the present disclosure.

[0172] The control unit (170) of the display device (100) according to the embodiment can extract local area-specific information of the entire area and generate a local area contrast curve for each local area that reflects the local area-specific information.

[0173] The local area contrast curve may refer to the first local mapping curve, the second local mapping curve, and the third local mapping curve described above.

[0174] The first curve (1001) shown in FIG. 10 may be the DC curve of the base mapping curve for the entire area. The second curve (1003) represents an example of a local area contrast curve.

[0175] The second curve (1003) may correspond to the first local mapping curve, the second local mapping curve, and the third local mapping curve described with reference to FIGS. 5 through 8. In this case, the contrast of the second curve (1003) may be adjusted from the gain determined from the APL information and sharpness information of the local area. The first local mapping curve, the second local mapping curve, and the third local mapping curve may be generated based on the information of each local area and may be generated as local contrast curves of different shapes.

[0176] Additionally, the second curve (1003) may correspond to the first local mapping curve, the second local mapping curve, and the third local mapping curve described with reference to FIG. 9. In this case, the contrast of the second curve (1003) may be adjusted from a gain determined from the APL information, sharpness information, position information, and curvature information of the local area. The first local mapping curve, the second local mapping curve, and the third local mapping curve may be generated based on the information of each local area and may be generated as local contrast curves of different shapes.

[0177] Meanwhile, the control unit (170) of the display device (100) according to the embodiment may set the maximum value of the second curve (1003). This is because if the contrast is excessively enhanced, problems such as low-gradation burying or high-gradation saturation may occur. For example, if the second curve (1003) shown in FIG. 10 is a curve representing the maximum value set by the control unit (170), the first, second, and third local mapping curves generated for each local area may be generated to have values ​​between the first curve (1001) and the second curve (1003).

[0178] FIG. 11 is a drawing illustrating an example of a local contrast curve applied per APL according to an embodiment of the present disclosure.

[0179] The control unit (170) of the display device (100) according to the embodiment can generate different adaptive local contrast curves based on the APL information of the local area.

[0180] For example, the control unit (170) may generate a local contrast curve of the first curve (1101) when the APL level of the local area has a relatively low value. The control unit (170) may generate a local contrast curve of the second curve (1103) when the APL level of the local area has a relatively medium value. The control unit (170) may generate a local contrast curve of the third curve (1105) when the APL level of the local area has a relatively high value.

[0181] For example, the second curve (1103) in which the APL degree of the local area has a relatively intermediate value can be set so that the APL value at the point where the ratio of the input value to the output value is 1 has a larger APL value than the first curve (1101). The second curve (1103) in which the APL degree of the local area has a relatively intermediate value can be set so that the APL value at the point where the ratio of the input value to the output value is 1 has a smaller APL value than the third curve (1105).

[0182] In this way, the control unit (170) can adjust the shape of the local contrast curve of the corresponding local area according to the degree of APL of the local area. By measuring the degree of change of the local contrast curve of the corresponding area according to the change in the degree of APL of the local area in the display device (100), it can be determined whether the adaptive local mapping curve concept proposed in the present disclosure is applied. If there is a tendency for the local contrast curve to change according to the change in the degree of APL of the local area, it can be determined that the adaptive local mapping curve concept proposed in the present disclosure is applied.

[0183] FIG. 12 is a drawing illustrating the case where different sharpnesses are applied to the same APL according to an embodiment of the present disclosure.

[0184] The control unit (170) of the display device (100) according to the embodiment can generate different adaptive local contrast curves based on the sharpness information of the local area.

[0185] For example, the control unit (170) can make the local contrast tend to be greater as the sharpness of the local area becomes stronger in local areas with the same APL degree. The control unit (170) can generate a local contrast curve for the corresponding local area such that as the sharpness of the local area becomes stronger, the bright area becomes brighter and the dark area becomes darker.

[0186] The control unit (170) can generate local contrast curves having different contrast trends for different sharpnesses of the same APL.

[0187] The control unit (170) can generate a local contrast curve having a relatively high contrast tendency for a first sharpness pattern (1201) having a relatively high sharpness value. The control unit (170) can generate a local contrast curve having a relatively medium contrast tendency for a second sharpness pattern (1203) having a relatively medium sharpness value. The control unit (170) can generate a local contrast curve having a relatively low contrast tendency for a third sharpness pattern (1205) having a relatively low sharpness value.

[0188] In this way, the control unit (170) can adjust the shape of the adaptive local contrast curve according to the degree of sharpness of the local area. By detecting the degree of change in local contrast through luminance measurement in response to the change in the degree of sharpness of the local area in the display device (100), it can be determined whether the adaptive local mapping curve concept proposed in the present disclosure is applied. If there is a tendency for the local contrast to change through luminance measurement in response to the change in the degree of sharpness of the local area, it can be determined that the adaptive local mapping curve concept proposed in the present disclosure is applied.

[0189] FIG. 13 is a drawing illustrating, according to an embodiment of the present disclosure, a local area contrast curve for each APL according to a change in curvature and a case where different sharpnesses are applied at the same APL.

[0190] The control unit (170) according to the embodiment can generate different adaptive local contrast curves based on the curvature information of the local area. The control unit (170) can generate different adaptive local contrast curves based on the curvature information of the local area and the APL information. The control unit (170) can generate different adaptive local contrast curves based on the curvature information of the local area and the sharpness information. The control unit (170) can generate different adaptive local contrast curves based on the curvature information, APL information, and sharpness information of the local area.

[0191] In this way, the control unit (170) can adjust the shape of the local contrast curve of the corresponding local area according to the curvature information of the local area. By measuring the degree of change of the local contrast curve of the corresponding area according to the change in the degree of curvature of the local area in the display device (100), it can be determined whether the adaptive local mapping curve concept proposed in the present disclosure is applied. If there is a tendency for the local contrast curve to change according to the change in the degree of curvature of the local area, it can be determined that the adaptive local mapping curve concept proposed in the present disclosure is applied.

[0192] The control unit (170) can perform tone mapping for each local area using an adaptive local mapping curve that reflects information for each local area.

[0193] The image according to the output image data for which adaptive local tone mapping has been performed for each local area in the control unit (170) can be displayed on the display unit (180).

[0194] According to the display device and driving method according to the embodiment of the present disclosure, by utilizing information of a local area of ​​an image, the contrast ratio in the local area can be improved, and the three-dimensionality of the image and user immersion can be enhanced.

[0195] According to the display device and driving method according to the embodiment of the present disclosure, by utilizing APL information, sharpness information, and position information of a local area of ​​an image, the contrast ratio in the local area can be improved, and the three-dimensionality of the image and user immersion can be enhanced.

[0196] According to the display device and driving method according to the embodiment of the present disclosure, the three-dimensionality of the image and user immersion can be further enhanced by utilizing APL information, sharpness information, position information, and curvature information of the local area of ​​the image.

[0197] According to the display device and driving method according to the embodiment of the present disclosure, adaptive local tone mapping is performed for each local area based on information for each local area of ​​the image, thereby further enhancing the three-dimensionality of the image and user immersion.

[0198] FIG. 14 is a flowchart illustrating a method for driving a display device according to another embodiment of the present disclosure.

[0199] Referring to Fig. 14, The control unit (170) can apply a global contrast curve to the entire area of ​​the original image (S1401).

[0200] The global contrast curve can be a dynamic contrast curve for the entire area of ​​the original image.

[0201] A dynamic contrast curve can be a curve that outputs bright parts of an image brighter and dark parts of an image darker.

[0202] The control unit (170) may receive metadata along with the image data when receiving the image data. The input image data may be an HDR image.

[0203] Metadata may include information about the input image data. Metadata may include at least one of luminance information of the HDR image, maximum brightness information per scene, and information for identifying that it is an HDR image.

[0204] In addition, the control unit (170) can calculate a luminance distribution histogram over the entire area of ​​the input image data.

[0205] The luminance distribution histogram of an HDR image may represent distribution information of the brightness values ​​of each pixel of the HDR image. The control unit (170) can calculate a luminance distribution histogram which is a distribution of the signal levels (e.g., 0 to 1023) of each pixel of the HDR image.

[0206] The control unit (170) can generate a Dynamic Tone Mapping (DTM) curve based on luminance distribution histogram information for the input image data. The DTM curve may refer to a mapping curve in the RGB domain. In the RGB domain, mapping from the input image data to the output image data can be performed according to the generated DTM curve.

[0207] The control unit (170) can generate a global DC (Dynamic Contrast) curve. The DC curve may represent a mapping curve in the luminance (Y) domain. In the luminance (Y) domain, mapping from input image data to output image data can be performed in accordance with the generated TC curve.

[0208] Meanwhile, since a method for generating DTM curves and DC curves in the control unit (170) to generate output image data suitable for the characteristics of the display unit (180) for input image data is known, a detailed explanation thereof will be omitted here.

[0209] After applying a global contrast curve to the original image, the control unit (170) can apply a local contrast curve to each of the multiple local regions that constitute the entire area of ​​the original image (S1403).

[0210] The entire area of ​​the original image can be divided into multiple local regions.

[0211] The control unit (170) can apply a local contrast cover to each local area to enhance the expressiveness of the local area (or local block) that is brightened or darkened by the global DC curve.

[0212] The control unit (170) can acquire the APL of each local area and apply a local contrast curve to each local area according to the acquired APL.

[0213] In other words, the local contrast curve can also change depending on the APL of the local area.

[0214] For an embodiment in which different local contrast curves are applied according to the APL of the local area, the embodiments of FIGS. 5 to 11 may be used.

[0215] The control unit (170) obtains the intensity of each local contrast curve (S1405), and based on the intensity of the obtained local contrast curve, can adjust the intensity of noise processing or sharpness for the local output image to which the local contrast curve is applied (S1407).

[0216] The intensity of the local contrast curve may vary depending on the APL of the local area (local APL).

[0217] In one embodiment, the intensity of the local contrast curve may correspond to the slope of the local contrast curve.

[0218] The storage unit (140) of the display device (100) can store the correspondence between the intensity of the local contrast curve and the intensity of the noise processing, the correspondence between the intensity of the local contrast curve and the intensity of the sharpness, and the correspondence between the intensity of the local contrast curve, the intensity of the noise processing and the intensity of the sharpness as a look-up table (LUT).

[0219] The control unit (170) can increase the noise processing intensity and decrease the clarity intensity when the intensity of the local contrast curve increases.

[0220] The control unit (170) can reduce the noise processing intensity and increase the clarity intensity when the intensity of the local contrast curve decreases.

[0221] The intensity of noise processing and the intensity of sharpness may have an inverse relationship. That is, as the intensity of noise processing increases, the intensity of sharpness may decrease, and as the intensity of noise processing decreases, the intensity of sharpness may increase.

[0222] The control unit (170) can adjust only the intensity of sharpness according to the intensity of the local contrast curve when noise processing is unnecessary.

[0223] The control unit (170) can output an image to the display unit (180) in which one or more of the noise processing intensity or clarity intensity are adjusted.

[0224] FIGS. 15a and FIGS. 15b are drawings illustrating a process of adjusting the noise intensity or sharpness intensity of a local area within the entire area of ​​an original image according to an embodiment of the present disclosure.

[0225] Referring to FIG. 15a, the original image (1510) can be output to the display unit (180).

[0226] The original video (1510) may be a video received through an external device interface unit (135), a network interface unit (133), a tuner (131), or a wireless communication unit (173).

[0227] The control unit (170) can generate a first output image (1530) by applying a global contrast curve (1520) to the original image (1510).

[0228] The control unit (170) can measure the APL of the entire area of ​​the original image (1510) and generate a global contrast curve (1520) based on the measured APL.

[0229] The global contrast curve (1520) may be a curve that adjusts the brightness of an image to make the bright parts of the image brighter and the dark parts of the image darker.

[0230] The image of the local area (1531) of the first output image (1530) can be expressed darker than the original by the global contrast curve (1510).

[0231] As shown in FIG. 15b, the control unit (170) can acquire the local APL of the local area (1531) to enhance the expressiveness of the local area (1531) and generate a local contrast curve (1540) based on the acquired local APL.

[0232] The control unit (170) can generate a second output image (1550) by applying a local contrast curve (1540) to a local area (1531) of the first output image (1530).

[0233] Digital noise generated by forcibly changing the image signal can be boosted in the local image (1560) displayed in the local area (1531) of the second output image (1550).

[0234] As a result, digital noise may be visible to the naked eye, which may lead to a degradation in image quality.

[0235] The control unit (170) can adjust one or more of the noise processing intensity or the clarity intensity based on the intensity of the local contrast curve (1540) corresponding to the local area (1531).

[0236] Accordingly, noise in the local image (1560) can be removed, and a clear image can be provided.

[0237] Figure 16 is a diagram illustrating a pivot table according to the local APL.

[0238] The pivot table (1600) may be a table representing the local APL of each of the multiple local regions included in the entire area of ​​the image.

[0239] The pivot table (1600) may include a pivot table for a bright scene, a pivot table for a dark scene, and an interpolation area.

[0240] The first image (1610) is a generally dark image, but includes a bright area (1611). The bright area (1611) can be matched to a pivot table for dark scene.

[0241] The second image (1630) is a bright image overall, but includes a dark area (1631). The dark area (1631) can be matched to a pivot table for a bright scene.

[0242] The control unit (170) can acquire the local APL of the bright area (1611) of the first image (1610) and generate the first local contrast curve (1613) based on the local APL.

[0243] The control unit (170) can express high gradation by applying a first local contrast curve (1613) having low intensity to a bright area (1611) of the first image (1610).

[0244] However, in this case, digital noise may occur. The control unit (170) can obtain the intensity of the first local contrast curve (1613) and obtain a noise processing intensity or clarity intensity corresponding to the obtained intensity.

[0245] The control unit (170) can extract a noise processing strength or sharpness strength that matches the strength of the first local contrast curve (1613) using a lookup table stored in the storage unit (140).

[0246] The control unit (170) can apply the extracted noise processing intensity or sharpness intensity to the bright area (1611) of the first image (1610).

[0247] The control unit (170) can acquire the local APL of the dark area (1631) of the second image (1630) and generate a second local contrast curve (1633) based on the local APL.

[0248] The control unit (170) can express low grayscale by applying a second local contrast curve (1633) with high intensity to a dark area (1611) of the second image (1630).

[0249] However, in this case, digital noise may occur as the dark area (1611) is expressed. The control unit (170) can obtain the intensity of the second local contrast curve (1633) and obtain a noise processing intensity or clarity intensity corresponding to the obtained intensity.

[0250] The control unit (170) can extract a noise processing strength or sharpness strength that matches the strength of the second local contrast curve (1633) using a lookup table stored in the storage unit (140).

[0251] The control unit (170) can apply the extracted noise processing intensity or sharpness intensity to the dark area (1631) of the second image (1630).

[0252] Accordingly, noise in the dark area (1631) is suppressed, and image degradation in the darker area (1631) can be prevented.

[0253] Figure 17a is a diagram illustrating a lookup table for classifying some areas of a dark image into bright areas according to APL and for adjusting noise or sharpness of each classified bright area.

[0254] Figure 17b is a diagram illustrating a lookup table for classifying some areas of a bright image into dark areas according to APL and for adjusting noise or sharpness of each classified dark area.

[0255] The lookup table (1700) can be stored in the storage unit (140).

[0256] Referring to FIG. 17a, a plurality of bright regions (PIVOT_DARK0 to PIVOT_DARK7) within the entire dark image area can be classified according to the APL of each region.

[0257] Each bright area can be mapped to a point on the pivot table (1600) described in Fig. 16.

[0258] The control unit (170) can obtain one or more of the noise processing strength or clarity strength corresponding to each bright area through the lookup table (1700).

[0259] The control unit (170) can apply the acquired noise processing intensity or sharpness intensity to the corresponding bright area. Accordingly, digital noise processing or a sharpened image can be output through the display unit (180) for the bright image.

[0260] Referring to Fig. 17b, multiple dark regions (PIVOT_BRIGHT0 to PIVOT_BRIGHT 7) within the entire bright image area can be classified according to the APL of each region.

[0261] Each dark area can be mapped to a point on the pivot table (1600) described in Fig. 16.

[0262] The control unit (170) can obtain one or more of the noise processing strength or clarity strength corresponding to each dark area through the lookup table (1700).

[0263] The control unit (170) can apply the acquired noise processing strength or sharpness strength to the corresponding dark area. Accordingly, digital noise processing or a sharpened image can be output through the display unit (180) for the dark image.

[0264] FIG. 18 is a drawing illustrating the configuration of a control unit according to one embodiment of the present disclosure.

[0265] Referring to FIG. 18, the control unit (170) may include a noise processing unit (1801), a sharpness adjustment unit (1803), and a local contrast control unit (1805).

[0266] The noise processing unit (1801) can remove noise from the image. The noise processing unit (1801) may include a low-pass filter.

[0267] A low-pass filter can remove video signals corresponding to high frequencies and allow video signals corresponding to relatively low frequencies to pass through.

[0268] The noise processing intensity can be adjusted according to the local APL of the local area of ​​the noise processing unit (1801) or the intensity (or gain) of the local contrast curve based on the local APL.

[0269] The noise processing strength can be the strength of the low-pass filter.

[0270] The noise processing unit (1801) can adjust the noise processing intensity based on local information of the local area. The local information of the local area may include one or more of the intensity of the APL of the local area or the local contrast curve.

[0271] The noise processing unit (1801) can receive local information through the local contrast control unit (1805).

[0272] The sharpness control unit (1803) can control the intensity of the sharpness of the noise-processed image.

[0273] The sharpness control unit (1803) can control the intensity of the sharpness of the image by using one or more of an unsharp mask filter, a sharp mask filter, and a blur filter.

[0274] The intensity of sharpness can represent the intensity of each filter.

[0275] The sharpness control unit (1803) can adjust the sharpness according to the strength (or gain) of the local APL of the local area or the local contrast curve based on the local APL.

[0276] The sharpness control unit (1803) can control the intensity of sharpness based on local information of the local area. The local information of the local area may include one or more of the intensity of the APL of the local area or the local contrast curve.

[0277] The clarity control unit (1803) can receive local information through the local contrast control unit (1805).

[0278] The local contrast control unit (1805) can acquire the local APL of each of the multiple local regions constituting the entire area of ​​the image and generate a local contrast curve based on the acquired local APL.

[0279] The local contrast control unit (1805) can apply the generated local contrast curve to the corresponding local area.

[0280] Conventionally, because the configuration controlling local contrast for a local area is located after the noise processing unit and sharpness adjustment unit, there was no factor capable of eliminating detail loss or digital noise caused by the local contrast curve.

[0281] Therefore, there is a problem where differences in detail loss or noise levels occur in visually bright and dark areas depending on the intensity of the local contrast curve of the corresponding local region.

[0282] A display device (100) according to an embodiment of the present disclosure can adjust the processing intensity of digital noise or the intensity of clarity generated by a local contrast curve according to local information for each local area.

[0283] Accordingly, digital noise generated in each local area is suppressed and detail loss is significantly reduced, allowing for the provision of clean and sharp image quality.

[0284] Meanwhile, whether a concept for controlling noise processing intensity or clarity intensity is applied according to local information according to the present disclosure can be determined through the following process.

[0285] First, as shown in FIG. 11, by measuring the degree of change of the local contrast curve of the corresponding area according to the change in the degree of APL of the local area in the display device (100), it can be determined whether the adaptive local mapping curve concept proposed in the present disclosure has been applied.

[0286] That is, if the local contrast curve tends to change according to the change in the degree of APL of the local area, it can be determined that the adaptive local mapping curve concept proposed in the present disclosure has been applied.

[0287] In addition, if the brightness of a local area tends to become brighter or darker as the intensity of sharpness or noise processing increases for each local area, it can be determined that a concept for adjusting the intensity of noise processing or sharpness is applied based on local information.

[0288] The display unit (180) according to the embodiment of the present disclosure can also be applied to a bendable display that forms a curved surface.

[0289] In addition, the display device (100) according to the embodiment of the present disclosure may also be applied to a stand-type device having a stand, a support, and a display unit (180).

[0290] The above description is merely an illustrative explanation of the technical concept of the present disclosure, and those skilled in the art to which the present disclosure pertains may make various modifications and variations within the scope of the essential characteristics of the present disclosure without departing from its nature.

[0291] Accordingly, the disclosed embodiments are intended to explain, not limit, the technical concept of the present disclosure, and the scope of the technical concept of the present disclosure is not limited by these embodiments.

[0292] The scope of protection of the present disclosure shall be interpreted by the claims below, and all technical ideas within the equivalent scope shall be interpreted as being included within the scope of rights of the present disclosure.

Claims

Claim 1 A display device comprising: a display unit; and a control unit that applies a global contrast curve for adjusting brightness over an entire area of ​​an input image, generates a plurality of local contrast curves corresponding to each of a plurality of local areas based on local information of each of a plurality of local areas included in the entire area, applies each local contrast curve to each local area, and adjusts one or more of the noise processing intensity or sharpness intensity of a local output image to which the local contrast curve is applied based on each local information.The control unit includes a pivot table representing a first local APL (Average Peak Luminance) for a bright area and a second local APL for a dark area among a plurality of local areas included in the entire area, and a lookup table representing a correspondence relationship between the intensity of the local contrast curve, the noise processing intensity, and the sharpness intensity. When generating the local contrast curve, the control unit checks the amount of change in luminance values ​​for adjacent pixels within a certain distance from each local area and determines whether to generate the local contrast curve for each local area based on the amount of change in luminance values. If the input image is a first image that includes a local area having a luminance higher than the luminance of the entire area, the control unit obtains the first local APL for the bright area from the pivot table, generates the first local contrast curve based on the first local APL, extracts the noise processing intensity or sharpness intensity corresponding to the first local contrast curve from the lookup table, and the extracted noise processing intensity or sharpness intensity is the A display device that applies to a local area of ​​a first image, and if the input image is a second image that includes a local area having a lower luminance than the luminance of the entire area, obtains a second local APL for the dark area from the pivot table, generates a second local contrast curve based on the second local APL, extracts a noise processing strength or sharpness strength corresponding to the second local contrast curve from the lookup table, and applies the extracted noise processing strength or sharpness strength to the local area of ​​the second image. Claim 2 A display device according to claim 1, wherein the local information is either the intensity of a local contrast curve or the local APL (Average Peak Luminance) of a local area. Claim 3 delete Claim 4 delete Claim 5 delete Claim 6 delete Claim 7 A display device according to claim 1, wherein the noise processing strength and the clarity strength are inversely proportional to each other. Claim 8 A method for driving a display device comprises: applying a global contrast curve that controls the luminance of an entire area of ​​an input image; storing a pivot table representing a first local APL (Average Peak Luminance) for a bright area and a second local APL for a dark area among a plurality of local areas included in the entire area, and a lookup table representing a correspondence relationship between the intensity of the local contrast curve, the noise processing intensity, and the intensity of the sharpness; generating a plurality of local contrast curves corresponding to each of the plurality of local areas based on local information of each of the plurality of local areas included in the entire area; and applying each local contrast curve to each local area.and includes a step of adjusting one or more of the noise processing intensity or sharpness intensity of the local output image to which the local contrast curve is applied based on each local information, and the step of generating the local contrast curve includes checking the amount of change in luminance values ​​for adjacent pixels within a certain distance in each local area and determining whether to generate the local contrast curve for each local area based on the amount of change in luminance values; if the input image is a first image that includes a local area having a luminance higher than the luminance of the entire area, a first local APL for the bright area is obtained from the pivot table and a first local contrast curve is generated based on the first local APL; if the input image is a second image that includes a local area having a luminance lower than the luminance of the entire area, a second local APL for the dark area is obtained from the pivot table and a second local contrast curve is generated based on the second local APL; and the step of applying each local contrast curve includes, to the first local contrast curve from the lookup table A driving method for a display device, comprising extracting a corresponding noise processing strength or sharpness strength and applying the extracted noise processing strength or sharpness strength to a local area of ​​the first image, and extracting a noise processing strength or sharpness strength corresponding to the second local contrast curve from the lookup table and applying the extracted noise processing strength or sharpness strength to a local area of ​​the second image.; Claim 9 A driving method for a display device, wherein the local information is either the intensity of a local contrast curve or the local APL (Average Peak Luminance) of a local area. Claim 10 delete Claim 11 delete Claim 12 delete Claim 13 delete Claim 14 A driving method for a display device according to claim 8, wherein the noise processing strength and the clarity strength are inversely proportional to each other.

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