Patent Description:
The present disclosure relates to a display device and method, and more particularly, to a display device and method for processing an image to correct a color of an image and output the color-corrected image.

A display device is a device having a function of receiving, processing, and displaying an image that may be viewed by a user. The display device receives, for example, a broadcast signal selected by a user among broadcast signals transmitted from a broadcasting station, separates an image signal from the received signal, and displays the separated image signal on a display.

Meanwhile, it is important for the display device to provide a user with an image of visibility enabling a shape or color of an object to be easily identified even from a distance, natural color, and clear image quality.

To this end, various methods such as image enhancement, color enhancement, white balance adjustment, image brightness conversion using a lookup table, and color adjustment using color gain are provided.

Meanwhile, a typical method among the methods mentioned above is to enhance an output image by correcting brightness of the image, but this method has a problem in that a clear image cannot be provided due to color distortion that occurs as excessive enhancement is applied to a skin color of a human or an object having a color similar to the skin color of the human. <CIT> relates to a method, system, and article provide automatic white balancing with skin tone correction for image processing. <CIT> relates to display systems and methods for adjusting backlight illumination. <CIT> relates to white balance processing method and apparatus. <CIT> relates to a display device including a setting condition acquisition unit for obtaining various conditions for adjusting a gain of a video-signal, a currentbrightness table calculation unit that calculates a table representing a relationship between an average brightness and a gain of a video-signal. <NPL> relates to a Gamut-Mapping algorithm with separate skin and non-skin color preference controls for Wide-Color-Gamut TV.

An aspect of the present disclosure is directed to preventing color distortion that occurs according to enhancement of an image.

Another aspect of the present disclosure is directed to preventing an occurrence of color distortion in a specific part of an image by correcting a color of an image through face detection using an artificial intelligence model.

The brightness converting unit may be configured to acquire a brightness value corresponding to each unit pixel included in the image, to acquire a corrected brightness value corresponding to the brightness value through a look-up table including a linear or nonlinear section, and to acquire a brightness corrected image obtained by correcting the brightness value of each unit pixel based on the corrected brightness value.

The controller may be configured to output the brightness corrected image through the display unit when a person is not detected in the image.

The controller may be configured to extract a person detected region when a person is detected in the image, to acquire the gain value corresponding to a size of the person detected region, to acquire the color corrected image by multiplying the color of the brightness corrected image by the gain value, and to output the color corrected image through the display unit.

The display device may further include a memory configured to store a gain table indicating the gain value corresponding to the size of the person detected region.

The gain value corresponding to the size of the person detected region may have a first gain value when the size of the person detected region is smaller than or equal to a preset first value and may have a value smaller than the first gain value when the size of the person detected region exceeds the preset first value.

The gain value corresponding to the size of the person detected region may have a first gain value when the size of the person detected region is a preset first value, may have a second gain value when the size of the person detected region is a preset second value, may have a third gain value when the size of the person detected region is a preset third value, the first value may be smaller than the second value, the second value may be smaller than the third value, the first gain value may be greater than the second gain value, and the second gain value may be greater than the third gain value.

A slope from the first gain value to the second gain value may be greater than a slope from the second gain value to the third gain value.

When a plurality of persons are detected in the image, the controller may be configured to extract each of the plurality of person detected regions, to acquire a gain value corresponding to the sum of sizes of the plurality of person detected regions, and to acquire the color corrected image by multiplying the color of the brightness corrected image by the gain value.

The color corrected image may be output through the display unit.

The display device may further include a color coordinate converting unit configured to convert a color into color coordinates, wherein the color coordinate converting unit may be configured to map a color of the image to a first color coordinate value, to map the brightness corrected image to a second color coordinate value, and a direction from the first color coordinate value to the second color coordinate value may follow a direction in which the color becomes lighter.

The controller may be configured to detect the person included in the image using at least one classifier among an object detection algorithm, a neural network, an Adaboost, or a support vector machine.

In another aspect of the present disclosure, there is provided a method of operating a display device including: acquiring a brightness corrected image by correcting brightness of an image; detecting a person included in the image; acquiring a color corrected image by correcting a color of the brightness corrected image according to whether a person is detected; and outputting the color corrected image.

The acquiring of the brightness corrected image may include: acquiring a brightness value corresponding to each unit pixel included in the image; acquiring a corrected brightness value corresponding to the brightness value using a look-up table; and acquiring a brightness corrected image based on the corrected brightness value.

The acquiring of the color corrected image may include: extracting a person detected region when a person is detected in the image; acquiring the gain value corresponding to a size of the person detected region; and acquiring the color corrected image by multiplying the color of the correction image by the gain value.

Hereinafter, embodiments related to the present disclosure will be described more specifically with reference to the drawings. The suffixes "module" and "unit" for components used in the following description are given or used interchangeably in consideration of only the ease of preparation of the specification, and do not themselves have distinct meanings or roles.

Hereinafter, embodiments related to the present disclosure will be described in detail with reference to the accompanying drawings. In the following description, usage of suffixes such as "module", "part" or "unit" used for referring to elements is given merely to facilitate explanation of the present invention, without having any significant meaning by itself.

<FIG> is a block diagram illustrating a configuration of a display device according to an embodiment of the present disclosure.

Referring to <FIG>, a display device <NUM> may include a broadcast receiving unit <NUM>, an external device interface unit <NUM>, a storage unit <NUM>, a user input interface unit <NUM>, a controller <NUM>, and a wireless communication unit. <NUM>, a voice acquiring unit <NUM>, a display unit <NUM>, an audio output unit <NUM>, and a power supply unit <NUM>.

The broadcast receiving unit <NUM> may include a tuner <NUM>, a demodulation unit <NUM>, and a network interface unit <NUM>.

The tuner <NUM> may select a specific broadcast channel according to a channel selection command. The tuner <NUM> may receive a broadcast signal for the selected specific broadcast channel.

The demodulation unit <NUM> may separate the received broadcast signal into a video signal, an audio signal, and a data signal related to a broadcast program, and restore the separated video signal, audio signal, and data signal into an outputtable form.

The network interface unit <NUM> may provide an interface for connecting the display device <NUM> to a wired/wireless network including the Internet. The network interface unit <NUM> may transmit or receive data to or from other users or other electronic devices via a connected network or another network linked to the connected network.

The network interface unit <NUM> may access a predetermined web page through a connected network or another network linked to the connected network. That is, the network interface unit <NUM> may transmit or receive data to or from a corresponding server by accessing the predetermined web page through a network.

In addition, the network interface unit <NUM> may receive content or data provided by a content provider or a network operator. That is, the network interface unit <NUM> may receive content such as movies, advertisements, games, VODs, broadcast signals, and related information provided from a content provider or a network provider via a network.

In addition, the network interface unit <NUM> may receive update information and an update file of firmware provided by the network operator, and may transmit data to the Internet or content provider or network operator.

The network interface unit <NUM> may select and receive a desired application from among applications open to the public via a network.

The external device interface unit <NUM> may receive an application or an application list in an adjacent external device and transmit the received list to the controller <NUM> or the storage unit <NUM>.

The external device interface unit <NUM> may provide a connection path between the display device <NUM> and an external device. The external device interface unit <NUM> may receive one or more of an image and audio output from an external device connected to the display device <NUM> by wire or wirelessly and transfer the received image or audio to the controller <NUM>. The external device interface unit <NUM> may include a plurality of external input terminals. The plurality of external input terminals may include an RGB terminal, one or more high definition multimedia interface (HDMI) terminals, and a component terminal.

An image signal of an external device input through the external device interface unit <NUM> may be output through the display unit <NUM>. An audio signal of the external device input through the external device interface unit <NUM> may be output through the audio output unit <NUM>.

An external device connectable to the external device interface unit <NUM> may be any one of a set-top box, a Blu-ray player, a DVD player, a game machine, a sound bar, a smartphone, a PC, a USB memory, and a home theater, but this is merely an example.

In addition, part of content data stored in the display device <NUM> may be transmitted to another user registered in advance in the display device <NUM> or to a selected user or selected electronic from among other electronic devices.

The storage unit <NUM> may store a program for processing and controlling each signal in the controller <NUM> and may store a signal-processed image, audio, or data signal.

In addition, the storage unit <NUM> may perform a function for temporarily storing of an image, audio, or data signal input from the external device interface unit <NUM> or the network interface unit <NUM> and store information regarding a predetermined image through a channel memory function.

The storage unit <NUM> may store an application or an application list input from the external device interface unit <NUM> or the network interface unit <NUM>.

The display device <NUM> may play content files (movie files, still image files, music files, document files, application files, etc.) stored in the storage unit <NUM> and provide the same to the user.

The user input interface unit <NUM> may receive and process a control signal such as power ON/OFF, channel selection, screen setting, or the like, from the remote controller <NUM> according to various communication methods such as Bluetooth, ultra-wideband (WB), ZigBee method, radio frequency (RF) communication method, or infrared (IR) communication method or process a control signal form the controller so as to be transmitted to the remote controller <NUM>.

In addition, the user input interface unit <NUM> may transmit a control signal input from a local key (not shown) such as a power key, a channel key, a volume key, and a set value to the controller <NUM>.

An image signal processed by the controller <NUM> may be input to the display unit <NUM> and displayed as an image corresponding to the image signal. Also, the image signal processed by the controller <NUM> may be input to an external output device through the external device interface unit <NUM>.

An audio signal processed by the controller <NUM> may be audio output to the audio output unit <NUM>. In addition, a voice signal processed by the controller <NUM> may be input to an external output device through the external device interface unit <NUM>.

In addition, the controller <NUM> may control an overall operation of the display device <NUM>.

In addition, the controller <NUM> may control the display device <NUM> by a user command or an internal program input through the user input interface unit <NUM> and download an application or application list desired by the user to the display device <NUM> by accessing the network.

The controller <NUM> may cause channel information selected by the user or the like to be output through the display unit <NUM> or the audio output unit <NUM> together with a processed image or audio signal.

In addition, the controller <NUM> may cause an image signal or an audio signal from an external device, e.g., a camera or a camcorder, input through the external device interface unit <NUM> to be output through the display unit <NUM> or the audio output unit <NUM> according to an external device image playback command received through the user input interface unit <NUM>.

Meanwhile, the controller <NUM> may control the display unit <NUM> to display an image. For example, the controller <NUM> may control a broadcast image input through the tuner <NUM>, an external input image input through the external device interface unit <NUM>, and image input through a network interface unit, or an image stored in the storage unit <NUM> to be displayed on the display unit <NUM>.

In addition, the controller <NUM> may control content stored in the display device <NUM>, received broadcast content, and external input content input from the outside to be played, and the content may be in various forms such as a broadcast image, an external input image, and an audio file, a still image, a connected web screen, and a document file.

The wireless communication unit <NUM> may communicate with an external device through wired or wireless communication. The wireless communication unit <NUM> may perform short range communication with an external device. To this end, the wireless communication unit <NUM> may support short-range communication using at least one of Bluetooth™, Bluetooth low energy (BLE), radio frequency identification (RFID), infrared data association (IrDA), ultra-wideband (UWB), ZigBee, near field communication (NFC), wireless-fidelity (Wi-Fi), Wi-Fi Direct, and wireless universal serial bus (USB) technologies. The wireless communication unit <NUM> may support wireless communication between the display device <NUM> and a wireless communication system, between the display device <NUM> and another display device <NUM>, or between the display device <NUM> and a network where the display device <NUM> (or external server) is located through wireless region networks.

Here, the other display device <NUM> may be a mobile terminal such as a wearable device (e.g., smartwatch) capable of exchanging (or interworking with) data with the display device <NUM> according to the present disclosure, smart glass, head-mounted display (HMD), or a smart phone. The wireless communication unit <NUM> may detect (or recognize) a wearable device capable of performing communication near the display device <NUM>. Furthermore, when the detected wearable device is an authenticated device authenticated to communicate with the display device <NUM> according to the present disclosure, the controller <NUM> may transmit at least part of data processed by the display device <NUM> to the wearable device through the wireless communication unit <NUM>. Accordingly, the user of the wearable device may use data processed by the display device <NUM> through the wearable device.

The voice acquiring unit <NUM> may acquire audio. The voice acquiring unit <NUM> may include at least one microphone (not shown) and may acquire audio around the display device <NUM> through a microphone (not shown).

The display unit <NUM> may convert each of an image signal, a data signal, an OSD signal processed by the controller <NUM> or an image signal, a data signal received from the external device interface unit <NUM> into R, G, and B signals to generate a driving signal.

Meanwhile, since the display device <NUM> shown in <FIG> is merely an embodiment of the present disclosure, some of the illustrated components may be integrated, added, or omitted according to specifications of the display device <NUM> which is actually implemented.

That is, if necessary, two or more components may be combined into one component, or one component may be subdivided into two or more components and configured. In addition, functions performed by each block are for explaining an embodiment of the present disclosure, and specific operations or devices thereof do not limit the scope of the present disclosure.

According to another embodiment of the present disclosure, the display device <NUM> may not include the tuner <NUM> and the demodulation unit <NUM> and may receive an image via the network interface unit <NUM> or the external device interface unit <NUM> and reproduce the received image.

For example, the display device <NUM> may be separated and implemented as an image processing device such as a set-top box for receiving a broadcast signal or content according to various network services and a content reproducing device for reproducing content input from the image processing device.

Here, a method of operating the display device according to the embodiment of the present disclosure to be described below may be performed by any one of the image processing device such as the separated set-top box or the like or the content reproducing device including the display unit <NUM> and the audio output unit <NUM>, as well as the display device <NUM> described above with reference to <FIG>.

The audio output unit <NUM> receives a signal processed by the controller <NUM> and outputs it as a voice.

The power supply unit <NUM> supplies corresponding power throughout the display device <NUM>. In particular, the power supply unit <NUM> may supply power to the controller <NUM> that may be implemented in the form of a system on chip (SOC), the display unit <NUM> for displaying an image, and the audio output unit <NUM> for outputting audio.

Specifically, the power supply unit <NUM> may include a converting unit that converts AC power into DC power and a dc/dc converting unit that converts a level of DC power.

Next, a remote controller according to an embodiment of the present disclosure will be described with reference to <FIG>.

<FIG> is a block diagram of a remote controller according to an embodiment of the present disclosure, and <FIG> shows an example of an actual configuration of a remote controller according to an embodiment of the present disclosure.

First, referring to <FIG>, the remote controller <NUM> may include a fingerprint recognition unit <NUM>, a wireless communication unit <NUM>, a user input unit <NUM>, a sensor unit <NUM>, an output unit <NUM>, a power supply unit <NUM>, a storage unit <NUM>, a controller <NUM>, and a voice acquiring unit <NUM>.

Referring to <FIG>, the wireless communication unit <NUM> transmits and receives signals to and from any one of the display devices according to the embodiments of the present disclosure described above.

The remote controller <NUM> may include an RF module <NUM> capable of transmitting and receiving signals to and from the display device <NUM> according to an RF communication standard and an IR module <NUM> capable of transmitting and receiving signals to and from the display device <NUM> according to an IR communication standard. In addition, the remote controller <NUM> may include a Bluetooth module <NUM> capable of transmitting and receiving signals to and from the display device <NUM> according to a Bluetooth communication standard. In addition, the remote controller <NUM> may include an NFC module <NUM> capable of transmitting and receiving signals to and from the display device <NUM> according to an NFC communication standard and a WLAN module <NUM> capable of transmitting and receiving signals to and from the display device <NUM> according to a wireless LAN (WLAN) communication standard.

In addition, the remote controller <NUM> transmits a signal including information on a movement of the remote controller <NUM> to the display device <NUM> through the wireless communication unit <NUM>.

Meanwhile, the remote controller <NUM> may receive a signal transmitted by the display device <NUM> through the RF module <NUM>, and if necessary, the remote controller <NUM> may transmit a command regarding power ON/OFF, channel change, volume change, and the like to the display device <NUM> through the IR module <NUM>.

The user input unit <NUM> may include a keypad, a button, a touch pad, or a touch screen. The user may input a command related to the display device <NUM> to the remote controller <NUM> by operating the user input unit <NUM>. When the user input unit <NUM> includes a hard key button, the user may input a command related to the display device <NUM> to the remote controller <NUM> through a push operation of the hard key button. This will be described with reference to <FIG>.

Referring to <FIG>, the remote controller <NUM> may include a plurality of buttons. The plurality of buttons may include a fingerprint recognition button <NUM>, a power button <NUM>, a home button <NUM>, a live button <NUM>, an external input button <NUM>, a volume control button <NUM>, a voice recognition button <NUM>, a channel change button <NUM>, an OK button <NUM>, and a back button <NUM>.

The fingerprint recognition button <NUM> may be a button for recognizing a user's fingerprint. As an example, the fingerprint recognition button <NUM> is available for a push operation, and thus the fingerprint recognition button <NUM> may receive a push operation and a fingerprint recognition operation. The power button <NUM> may be a button for turning on/off power of the display device <NUM>. The home button <NUM> may be a button for moving to a home screen of the display device <NUM>. The live button <NUM> may be a button for displaying a real-time broadcast program. The external input button <NUM> may be a button for receiving an external input connected to the display device <NUM>. The volume control button <NUM> may be a button for adjusting a volume output by the display device <NUM>. The voice recognition button <NUM> may be a button for receiving a user's voice and recognizing the received voice. The channel change button <NUM> may be a button for receiving a broadcast signal of a specific broadcast channel. The OK button <NUM> may be a button for selecting a specific function, and the back button <NUM> may be a button for returning to a previous screen.

When the user input unit <NUM> includes a touch screen, the user may input a command related to the display device <NUM> to the remote controller <NUM> by touching a soft key of the touch screen. In addition, the user input unit <NUM> may include various types of input units that a user may operate, such as a scroll key or a jog key, and the present embodiment does not limit the scope of the present disclosure.

The sensor unit <NUM> may include a gyro sensor <NUM> or an acceleration sensor <NUM>, and the gyro sensor <NUM> may sense information on a movement of the remote controller <NUM>.

For example, the gyro sensor <NUM> may sense information on an operation of the remote controller <NUM> based on x, y, and z axes, and the acceleration sensor <NUM> may sense information on a moving speed of the remote controller <NUM>. Meanwhile, the remote controller <NUM> may further include a distance measuring sensor to sense a distance to the display unit <NUM> of the display device <NUM>.

The output unit <NUM> may output an image or audio signal corresponding to an operation of the user input unit <NUM> or a signal transmitted from the display device <NUM>. Through the output unit <NUM>, the user may recognize whether the user input unit <NUM> is operated or whether the display device <NUM> is controlled.

For example, the output unit <NUM> may include an LED module <NUM> turned on when the user input unit <NUM> is operated or a signal is transmitted to or received from the display device <NUM> through the wireless communication unit <NUM>, a vibration module <NUM> generating vibration, an audio output module <NUM> for outputting sound, or a display module <NUM> for outputting an image.

In addition, the power supply unit <NUM> may supply power to the remote controller <NUM>, and if the remote controller <NUM> does not move for a predetermined time, the power supply unit <NUM> may stop power supply to reduce power waste. The power supply unit <NUM> may resume power supply when a predetermined key provided in the remote controller <NUM> is operated.

The storage unit <NUM> may store various types of programs and application data necessary for controlling or operating the remote controller <NUM>. If the remote controller <NUM> wirelessly transmits and receives signals to and from the display device <NUM> through the RF module <NUM>, the remote controller <NUM> and the display device <NUM> transmit and receive signals through a predetermined frequency band.

The controller <NUM> of the remote controller <NUM> may store information on a frequency band through which signals may be wirelessly transmitted and received to and from the display device <NUM> paired with the remote controller <NUM> in the storage unit <NUM> and refer to the same.

The controller <NUM> controls all matters related to the control of the remote controller <NUM>. The controller <NUM> may transmit a signal corresponding to an operation of a predetermined key of the user input unit <NUM> or a signal corresponding to a movement of the remote controller <NUM> sensed by the sensor unit <NUM> to the display device <NUM> through the wireless communication unit <NUM>.

In addition, the voice acquiring unit <NUM> of the remote controller <NUM> may acquire a voice.

The voice acquiring unit <NUM> may include at least one microphone <NUM> and may acquire a voice through the microphone <NUM>.

<FIG> shows an example of using a remote controller according to an embodiment of the present disclosure.

Conversely, when the user moves the remote controller <NUM> toward the display unit <NUM>, a selection region in the display unit <NUM> corresponding to the pointer <NUM> may be zoomed out and displayed in a reduced size.

Meanwhile, when the remote controller <NUM> is away from the display unit <NUM>, the selection region is zoomed out, and when the remote controller <NUM> is close to the display unit <NUM>, the selection region may be zoomed in.

In addition, when a specific button in the remote controller <NUM> is pressed, recognition of vertical and horizontal movement may be excluded. That is, when the remote controller <NUM> moves away from or approaches the display unit <NUM>, vertical and horizontal movements are not recognized but only forward and backward movements may be recognized. When a specific button in the remote controller <NUM> is not pressed, only the pointer <NUM> moves according to the vertical and horizontal movements of the remote controller <NUM>.

Meanwhile, a moving speed or moving direction of the pointer <NUM> may correspond to a moving speed or moving direction of the remote controller <NUM>.

Meanwhile, in the present disclosure, a pointer refers to an object displayed on the display unit <NUM> in response to an operation of the remote controller <NUM>. Accordingly, the pointer <NUM> may be used to make objects in various shapes other than the arrow shape shown in the drawing. For example, the pointer <NUM> may have a concept including a point, a cursor, a prompt, and a thick outline. In addition, the pointer <NUM> may be displayed to correspond to any one of a horizontal axis and a vertical axis on the display unit <NUM>, as well as a plurality of points such as a line and a surface.

Meanwhile, referring to <FIG>, the display device <NUM> of the present disclosure may further include a brightness converting unit <NUM> generating a brightness corrected image by correcting brightness of an image to be output, an object detecting unit <NUM> detecting a specific object included in an image, a color correcting unit <NUM> generating a color corrected image by correcting a color of the image using a gain value when a specific object is detected in the image, and a color coordinate converting unit <NUM> mapping pixel parameters to color coordinates.

Here, the controller <NUM> may control an overall operation of the display device <NUM>, control the brightness converting unit <NUM>, the object detecting unit <NUM>, the color correcting unit <NUM>, and the color coordinate converting unit <NUM>, and according to an embodiment, the controller <NUM> may perform operations of the brightness converting unit <NUM>, the object detecting unit <NUM>, the color correcting unit <NUM>, and the color coordinate converting unit <NUM>.

In addition, in describing an embodiment of the present disclosure, a brightness corrected image is acquired by adjusting brightness values (<NUM> to <NUM>) of a pixel and a color corrected image is acquired by adjusting a color value, but this is only an example and the embodiment of the present disclosure is not limited to a color model divided into a brightness value and a color value.

In other words, in correcting brightness or a color value according to an embodiment of the present disclosure, it may be sufficient to correct brightness or color by adjusting a parameter of a color model, and a color model in which brightness and the color are associated could also be used.

For example, the present disclosure may be applied to all display devices using a color model capable of correcting brightness and color, such as a gray model, an RGB model, an HSV model, and a YCbCr model.

Meanwhile, in an embodiment of the present disclosure, it is preferable to use a color model including a brightness value Y and a color CbCr value as separate parameters, such as YCbCr among the color models.

<FIG> shows a flowchart according to an embodiment of the present disclosure.

Referring to <FIG>, the controller <NUM> of the display device <NUM> may acquire an image (S510). Specifically, the image may include image data received from any one of the tuner <NUM>, the network interface unit <NUM>, and the external device interface unit <NUM>.

The brightness converting unit <NUM> may generate a brightness corrected image by adjusting brightness of the acquired image (S520). Specifically, the brightness converting unit <NUM> may acquire a brightness value corresponding to each unit pixel included in the image.

The brightness converting unit <NUM> may acquire a corrected brightness value according to a mapping value corresponding to the acquired brightness value. Here, the mapping value may be a predetermined value.

Specifically, a mapping value for converting the brightness value to the corrected brightness value may be determined through a look-up table including a linear or nonlinear section.

Here, the look-up table may refer to a graph corresponding to a brightness value and the corrected brightness value, and the shape or shape of the graph may be changed based on an image output from the display device.

The brightness converting unit <NUM> may acquire a brightness corrected image acquired by correcting the brightness value of each of the unit pixels based on the corrected brightness value.

More specifically, the brightness converting unit <NUM> may acquire a corrected brightness value corresponding to the brightness value of each unit pixel and acquire the brightness corrected image by applying the corrected brightness value to all pixels included in the image.

Meanwhile, the mapping value or mapping table may be predetermined during the process of releasing of the display device, and the mapping value or mapping table may be stored in the storage unit <NUM> of the display device.

Hereinafter, an example of generating a brightness corrected image will be described with reference to <FIG>.

<FIG> is a view illustrating a process of generating a brightness corrected image according to an embodiment of the present disclosure.

Referring to <FIG>, the brightness converting unit <NUM> may acquire a brightness value corresponding to each unit pixel included in an image <NUM>. For example, when the brightness value ranges from <NUM> to <NUM>, a brightness value <NUM> of a first pixel among a plurality of unit pixels included in the image <NUM> is '<NUM>', a brightness value <NUM> of a second pixel is '<NUM>', and a brightness value <NUM> of a third pixel is '<NUM>', then the brightness converting unit <NUM> may acquire corrected brightness values <NUM>, <NUM>, and <NUM> corresponding to the brightness value <NUM> of the first pixel, the brightness value <NUM> of the second pixel, and the brightness value <NUM> of the third pixel in the image <NUM>.

Specifically, the look-up table <NUM> may include a linear or nonlinear section and include at least one of a first section in which a brightness value is output as is when the brightness value is input, a second section in which a brightness value lower than the input brightness value is output when the brightness value is input, and a third section in which a brightness value higher than the input brightness value when the brightness value is input.

According to an embodiment of the present disclosure, referring to the look-up table <NUM> of <FIG>, the look-up table <NUM> including a combination of at least one first section and at least one third section is disclosed.

The brightness converting unit <NUM> may acquire a first corrected brightness value <NUM> corresponding to the brightness value <NUM> of the first pixel using the look-up table <NUM>. Similarly, the brightness converting unit <NUM> may acquire a second corrected brightness value <NUM> corresponding to the brightness value <NUM> of the second pixel and acquire a third corrected brightness value corresponding to the brightness value <NUM> of the third pixel <NUM>.

For example, the first corrected brightness value <NUM> may be mapped to '<NUM>' equal to the brightness value <NUM> of the first pixel, the second corrected brightness value <NUM> may be mapped to '<NUM>' greater than the brightness value <NUM> of the second pixel, and the third corrected brightness value <NUM> may be mapped to have the same '<NUM>' as the brightness value <NUM> of the third pixel.

The brightness converting unit <NUM> may acquire a corrected brightness value for each of the plurality of unit pixels included in the image using the look-up table <NUM> and acquire a final brightness corrected image <NUM>.

Here, the first pixel <NUM> of the brightness corrected image <NUM> may have a first corrected brightness value <NUM> and may have the same brightness value as the first pixel <NUM> of the image <NUM>.

In addition, the second pixel <NUM> of the brightness corrected image <NUM> may have a second corrected brightness value <NUM> and may have a higher brightness value than the second pixel <NUM> of the image <NUM>.

In addition, the third pixel <NUM> of the brightness corrected image <NUM> may have a third corrected brightness value <NUM> and may have the same brightness value as the third pixel <NUM> of the image <NUM>.

Referring to <FIG>, the object detecting unit <NUM> may detect an object included in an image (S530). Specifically, the object detecting unit <NUM> may detect a person included in the image using an artificial intelligence model. Here, the person may include face information.

According to an embodiment of the present disclosure, the artificial intelligence model may include various algorithms capable of detecting an object such as an object detection algorithm, and detect a person included in the image using at least one classifier among a neural network, Adaboost, and a support vector machine.

Meanwhile, the controller <NUM> may perform the role of the artificial intelligence model.

The artificial intelligence model may be stored in the storage unit <NUM> of the display device and may be received from an external server or an external device using the wireless communication unit <NUM>.

The controller <NUM> acquires a color corrected image by applying a gain value to a color of the brightness corrected image according to whether the person is detected.

According to an embodiment of the present disclosure, if the object detecting unit <NUM> does not detect a person because a person is not included in the image (S530-NO), the controller <NUM> outputs the brightness corrected image acquired in step S520 through the display unit <NUM> (S541).

If a face is not detected in the image, the controller <NUM> outputs an image whose brightness and color are enhanced compared to the existing image by outputting a brightness corrected image whose brightness is corrected. In the case of S541, since a face is not detected in the image, color distortion of a person detected region due to brightness correction may not occur.

According to an embodiment of the present disclosure, when the object detecting unit <NUM> detects a person in the image including a person (S530-YES), the controller <NUM> may extract a person detected region.

Specifically, the object detecting unit <NUM> may detect a person through the object detection algorithm or the classifier of the artificial intelligence model described above.

The controller <NUM> may classify the person among objects detected by the object detecting unit <NUM> and localize a region classified as a person. Here, the localized region may be a person detected region.

For example, the controller <NUM> may generate a bounding box in the region classified as a person and extract the region in which a person is detected. Here, the bounding box may have a width (w) and a height (h) based on a center point (x,y).

The controller <NUM> acquires a gain value corresponding to a size of the region in which a person is detected. Here, the size of the region in which the person is detected may be calculated as a product of the width (w) and the height (h) of the generated bounding box.

According to an embodiment of the present disclosure, the gain value may have the same value or a different value according to the size of the region in which a person is detected, and has a value of <NUM> or greater and <NUM> or less.

A relation between the size of the region in which a person is detected and the gain value may be displayed in a gain table, and the gain table may be stored in the storage unit <NUM> of the display device.

The process of acquiring the gain value will be described in detail later in <FIG> and <FIG>.

After the gain value is acquired, the controller <NUM> acquires the color corrected image by multiplying the color of the brightness corrected image by the gain value (S540).

Here, as described above, since the gain value has a value of <NUM> or less, the color corrected image may be darker than the brightness corrected image, or a color-related parameter may be set to be lighter.

As described above, by generating a color corrected image in which the color is further adjusted (down) by multiplying the brightness corrected image by the gain value, color distortion in a skin color of a person may be minimized by the brightness correction.

Thereafter, the controller <NUM> outputs a color corrected image through the display unit <NUM> (S550).

Hereinafter, an output result of the brightness corrected image to which the gain value is not applied in <FIG> will be described, and an output result of the color corrected image acquired by applying the gain value in <FIG> will be described.

<FIG> is a diagram for comparing an image output when color correction is performed on the image in which a person is detected and the output result of the image in which color correction is performed in <FIG>.

Referring to <FIG>, the object detecting unit <NUM> may detect a person <NUM> from an acquired image <NUM>.

The controller <NUM> may generate a bounding box <NUM> in a region classified as a person by localizing a face part of the region of the person <NUM> detected by the object detecting unit <NUM>.

For example, the controller <NUM> may generate a bounding box in the region classified as a person and extract the region <NUM> in which a person is detected. Here, the bounding box may have a width (w) and a height (h) based on a center point (x,y).

As described with reference to <FIG>, the brightness converting unit <NUM> may acquire a corrected brightness value of each unit pixel included in the image <NUM> by using the look-up table <NUM>.

For example, the brightness converting unit <NUM> may acquire a corrected brightness value <NUM> corresponding to the brightness value <NUM> of the first pixel of the image <NUM>. When the corrected brightness value of each unit pixel included in the image <NUM> is acquired, the brightness converting unit <NUM> may acquire the brightness corrected image <NUM>.

In the brightness corrected image <NUM>, a parameter related to a brightness value may be set high in at least one pixel included in the image <NUM>, and as the parameter related to the brightness value is set high, color distortion may occur in the region of the person 731of the brightness corrected image <NUM>.

In order to solve the problem occurring in the brightness corrected image <NUM> as shown in <FIG>, a process of acquiring a color corrected image according to a gain value of the present disclosure will be described in <FIG> below.

For example, the controller <NUM> may generate the bounding box <NUM> in the region classified as a person to extract a region in which a person is detected.

The brightness converting unit <NUM> may acquire a corrected brightness value of each unit pixel included in the image <NUM> by using the look-up table <NUM> as described with reference to <FIG>.

For example, a corrected brightness value <NUM> corresponding to the brightness value <NUM> of the first pixel of the image <NUM> may be acquired. When the corrected brightness value of each unit pixel included in the image <NUM> is acquired, the brightness converting unit <NUM> may acquire a brightness corrected image.

The controller <NUM> may acquire a gain value <NUM> corresponding to a size <NUM> of the region <NUM> in which the person <NUM> is detected. Here, the size <NUM> of the region in which a person is detected may be calculated as a product of a width and a height of the generated bounding box.

Here, the size <NUM> of the region in which a person is detected may include a size of the region in which the face of the person is detected, and a corresponding relation between the size of the region in which the face is detected and the gain value <NUM> may appear as a gain table <NUM>.

Here, the gain table <NUM> may be variously designed according to a type of an image, and a corresponding embodiment will be described with reference to <FIG>.

The controller <NUM> may acquire a color corrected image <NUM> by multiplying a color of the brightness corrected image by the acquired gain value <NUM>.

Specifically, the controller <NUM> may acquire the color corrected image <NUM> by multiplying a color parameter of each unit pixel included in the brightness corrected image by the acquired gain value <NUM> and combining the color parameters of the respective unit pixels to which the gain value <NUM> is assigned.

Here, since the gain value <NUM> has a value between <NUM> and <NUM>, a parameter value related to brightness or color of the color corrected image <NUM> is reduced compared to the brightness corrected image, thereby minimizing the occurrence of color distortion of a person detected region <NUM>.

Meanwhile, in the embodiment of the present disclosure, when a plurality of persons are detected in an image, the controller <NUM> may extract a plurality of person detected regions, acquire a gain value corresponding to the sum of sizes of the plurality of person detected regions, and acquire the color corrected image by multiplying the color of the brightness corrected image by the gain value.

For example, when a plurality of persons are detected, the controller <NUM> may extract each of faces of the plurality of people and acquire the sum of widths of bounding boxes of the extracted faces as a size <NUM> of the region in which a person is detected.

The controller <NUM> may acquire a gain value <NUM> corresponding to a size <NUM> of the region in which a person is detected, and acquire a color corrected image by multiplying the color of the brightness corrected image by the gain value <NUM>.

Thereafter, when the color corrected image is acquired, the controller <NUM> of the present disclosure may output the color corrected image through the display unit <NUM> (S550).

Meanwhile, in <FIG>, after the brightness corrected image according to the look-up table is generated (S520), person detection is performed (S530), but this is only an example and, after a person detection is first performed in the image, the brightness corrected image may be generated according to the look-up table.

Further, the object detecting unit <NUM> may perform object detection from an image or may perform object detection from a brightness corrected image.

<FIG> is a view illustrating a gain table according to an embodiment of the present disclosure.

Referring to <FIG>, a first gain table (a), a second gain table (b), and a third gain table (c) among examples of various gain tables are shown.

Referring to the first gain table (a), a gain value corresponding to a size of a person detected region may include a first gain value <NUM> if a size of the person detected region is equal to or smaller than a preset first value <NUM>, and may include a second gain value <NUM> smaller than the first gain value <NUM> if the size of the person detected region is a second value <NUM> exceeding the preset first value <NUM>.

Specifically, if the size of the person detected region exceeds a preset value using the first gain table (a) (not part of the invention), the controller <NUM> may acquire a color corrected image by decreasing the gain value.

The first gain table (a) may be used to generate a color corrected image based on experimental data in which color distortion rarely occurs when a size of a person detected region included in an image is smaller than a preset first value.

Referring to the second gain table (b), a gain value corresponding to the size of the person detected region has a first gain value <NUM> if the size of the person detected region is a preset first value <NUM>, has a second gain value <NUM> if the size of the person detected region is a preset second value <NUM>, and has a third gain value <NUM> if the size of the person detected region is a preset third value <NUM>.

Here, the first value <NUM> is smaller than the second value <NUM>, and the second value <NUM> is smaller than the third value <NUM>. Further, the first gain value <NUM> is greater than the second gain value <NUM>, and the second gain value <NUM> is greater than the third gain value <NUM>.

In addition, in the relation among the first gain value <NUM>, the second gain value <NUM>, and the third gain value <NUM>, a slope from the first gain value <NUM> to the second gain value <NUM> is greater than a slope from the second gain value <NUM> to the third gain value <NUM>.

In other words, the slope from the first value <NUM> to the second value <NUM> in the second gain table (b) may be steeper than the slope from the second value <NUM> to the third value <NUM>.

Specifically, the controller <NUM> may acquire a color corrected image by decreasing a gain value as the size of the person detected region increases using the second gain table (b).

In addition, as the size of the person detected region increases, the controller <NUM> decreases the gain value, and here, a reduction ratio may be set to be different for each specific section to acquire a color corrected image.

The second gain table (b) may be used to generate a color corrected image based on experimental data indicating that an increment of color distortion decreases if experimental data indicating that the influence of color distortion is large according to the presence or absence of a person detected region included in an image and a size of the person detected region equal to or greater than a preset value exist.

Meanwhile, the third gain table (c) shows an example of a case where, if a fourth value <NUM> greater than the third value <NUM> exists in the second gain table (b), a slope from the third gain value <NUM> to the fourth gain value <NUM> corresponding to the fourth value <NUM> increases compared with a slope from the second gain value <NUM> to the third gain value <NUM>.

As such, the gain table (a, b, c) may be designed in various ways according to the user setting and should not be interpreted to be limited to the form of the gain table shown in <FIG> of the present disclosure.

Hereinafter, in <FIG>, an experimental example in which a color related parameter is changed in a color corrected image as a result of applying a gain value according to a size of a person detected region according to the present disclosure will be described.

<FIG> is a diagram illustrating a color coordinate system according to an embodiment of the present disclosure.

The display device according to an embodiment of the present disclosure may further include a color coordinate converting unit <NUM> converting a color into color coordinates.

The color coordinate converting unit may convert a color value of a pixel acquired from an image into a color space and display the same in a coordinate system.

Referring to <FIG>, the color corrected images of the present disclosure are sequentially arranged from an image having a small size of a person detected region to an image having a large size of a person detected region as (a), (b), and (c) and color coordinates of the same pixel position are converted in color coordinates.

Specifically, the color coordinate converting unit <NUM> may map a color of the brightness corrected image (a) to a first color coordinate value <NUM>, map the brightness corrected image (b) to a second color coordinate value <NUM>, and the brightness corrected image c to a third color coordinate value <NUM>.

Here, it may be observed that a direction from the first color coordinate value <NUM> toward the second color coordinate value <NUM> follows a direction in which the color becomes lighter.

In addition, it may be observed that the direction from the second color coordinate value <NUM> toward the third color coordinate value <NUM> follows the direction in which the color becomes lighter.

Based on the experiment result, the display device <NUM> of the present disclosure may acquire a gain value according to whether a person is detected and acquire a color corrected image using the gain value, thereby preventing the occurrence of color distortion.

Meanwhile, a method of operating a display device according to an embodiment of the present disclosure may include acquiring a brightness corrected image by correcting brightness of an image, detecting a person included in the image, acquiring a color corrected image by correcting a color of the brightness corrected image according to whether a person is detected, and outputting the color corrected image.

In addition, the acquiring of the brightness corrected image may include acquiring a brightness value corresponding to each unit pixel included in the image, acquiring a corrected brightness value corresponding to the brightness value using a look-up table, and acquiring a brightness corrected image based on the corrected brightness value.

In addition, the acquiring of the color corrected image may include extracting a person detected region when a person is detected in the image, acquiring the gain value corresponding to a size of the person detected region, and acquiring the color corrected image by multiplying a color of the correction image by the gain value.

The present disclosure may generate a color corrected image based on a color gain and output the color corrected image, thereby providing an image without color distortion which is a side effect of image enhancement to the user.

The present disclosure may provide image enhancement optimized for an output image by using different color gains according to whether a person is detected.

According to the present disclosure, when a person is detected, an image enhancement optimized for an output image may be provided by setting a different color gain value corresponding to a size of a region where the person is detected.

The present disclosure may be implemented as a computer-readable code on a program recording medium. A computer-readable recording medium may be any recording medium that stores data that may be read by a computer system. Examples of the computer-readable medium include hard disk drive (HDD), solid state disk (SSD), silicon disk drive (SDD), read-only memory (ROM), random access memory (RAM), CD-ROM, magnetic tape, floppy disk, and optical data storage device. In addition, the computer may include the controller <NUM> of the display device <NUM>.

The above description is to simply illustrate the technical scope of the present disclosure and various modifications and substitutions can be made by those skilled in the art without departing from the scope of the present disclosure.

Accordingly, the embodiment disclosed in the present disclosure and the accompanying drawings are not intended to limit but describe the present disclosure, and the scope of the present disclosure is not limited by the embodiment and the accompanying drawings.

Claim 1:
A display device (<NUM>) comprising:
a display (<NUM>) configured to output an image having a plurality of unit pixels;
a brightness converter configured to acquire image data and to determine a brightness corrected image by correcting a brightness value corresponding to each unit pixel; and
a controller (<NUM>) configured to:
detect whether a face is included in the image;
determine a color corrected image based on whether the face is detected; and
output the color corrected image or the brightness corrected image through the display (<NUM>) based on whether the face is detected,
wherein:
when it is detected that a face is included in the image, multiply a color parameter of each unit pixel included in the brightness corrected image by a gain value so as to obtain the color corrected image and output the color corrected image through the display (<NUM>),
when it is not detected that a face is included in the image, output the brightness corrected image through the display (<NUM>),
characterized in that the controller (<NUM>) is further configured to:
extract a face detected region when the face is detected in the image;
acquire the gain value corresponding to a size of the face detected region, wherein the gain value has a value between <NUM> and <NUM>;
wherein the gain value corresponding to the size of the face detected region is equal to a first gain value when the size of the face detected region is equal to a preset first value, is equal to a second gain value when the size of the face detected region is equal to a preset second value, and is equal to a third gain value when the size of the face detected region is equal to a preset third value,
wherein the preset first value is smaller than the preset second value, the preset second value is smaller than the preset third value, the first gain value is greater than the second gain value, and the second gain value is greater than the third gain value, and
wherein a slope from the first gain value to the second gain value is greater than a slope from the second gain value to the third gain value.