Patent Publication Number: US-2022215792-A1

Title: Display device

Description:
TECHNICAL FIELD 
     The present disclosure relates to a display device, and more particularly, to a display device for displaying an image with an optimal picture quality according to a genre. 
     BACKGROUND ART 
     The resolution of a display device indicates how many pixels each frame constituting a screen is composed of. 
     With the advancement of technology, the resolution is continuously increasing, and the higher the resolution, the clearer the image can be expressed. However, as the number of pixels increases, the pixels are also composed of larger amount of data, so that more storage space and higher data processing speed are required. 
     Accordingly, the display device provides various image modes such that the screen is appropriately implemented according to the genre of images. For example, the display device provides a clear image mode for expressing a screen more clearly, a sports mode for vividly expressing fast movements, an eco mode for reducing power consumption, and the like. The display device may provide an appropriate picture quality to images by differently adjusting grayscale, color balance, color reproducibility, contrast, and the like according to an image mode. 
     On the other hand, there is a problem in that a user cannot switch image modes because he or she does not know the existence of the image modes, or the usability of the image modes is deteriorated due to the inconvenience of individually switching the image modes according to images. 
     DISCLOSURE 
     [Technical Problem] 
     An object of the present disclosure is to provide a display device capable of displaying images with an appropriate picture quality according to a genre of images that a user is watching. 
     Another object of the present disclosure is to provide a display device capable of minimizing a case where a user recognizes a change in picture quality when the picture quality is automatically changed according to images. 
     Still another object of the present disclosure is to provide a display device capable of minimizing an unnecessary change in picture quality. 
     Still another object of the present disclosure is to provide a display device capable of more accurately distinguishing genres of images. 
     [Technical Solution] 
     A display device according to an embodiment of the present disclosure may comprise a storage unit configured to store picture qualities for genres of images, a display unit configured to display an image corresponding to an input image signal, and a controller configured to acquire a genre of the image and change a picture quality of the image to a picture quality corresponding to the genre. 
     The controller of the display device according to an embodiment of the present disclosure may set the picture quality corresponding to the genre as a target picture quality, and control the display unit to change the picture quality of the image from a current picture quality to the target picture quality. 
     The controller of the display device according to an embodiment of the present disclosure may control the display unit such that the picture quality of the image is gradually changed for a set time. 
     The controller of the display device according to an embodiment of the present disclosure may fix the genre of the image during the set time. 
     The controller of the display device according to an embodiment of the present disclosure may increase the picture quality of the image when the target picture quality is higher than the current picture quality, and decrease the picture quality of the image when the target picture quality is lower than the current picture quality. 
     The controller of the display device according to an embodiment of the present disclosure may set a picture quality adjustment direction variable to a positive value when the target picture quality is higher than the current picture quality, and the picture quality adjustment direction variable to a negative value when the target picture quality is lower than the current picture quality. 
     The controller of the display device according to an embodiment of the present disclosure may acquire a picture quality adjustment step based on a set period of time for which the picture quality of the image is changed to the target picture quality. 
     The controller of the display device according to an embodiment of the present disclosure may control the display unit to change the picture quality of the image through a product of the picture quality adjustment step and the picture quality adjustment variable. 
     The controller of the display device according to an embodiment of the present disclosure may acquire the genre of the image at set periods. 
     The picture quality according to an embodiment of the present disclosure may include at least one of contrast, brightness, sharpness, color depth, and color temperature. 
     The controller of the display device according to an embodiment of the present disclosure acquire an EPG, an audio signal, and a video signal from the image signal, and acquire the genre of the image based on at least one of the EPG, the audio signal, and the video signal. 
     The controller of the display device according to an embodiment of the present disclosure may acquire the genre of the image based on the EPG when the genre of the image is detectable from the EPG, and acquire the genre of the image based on at least one of the audio signal and the video signal when the genre of the image is undetectable from the EPG. 
     The controller of the display device according to an embodiment of the present disclosure may calculate probabilities that the image corresponds to a plurality of genres, and recognize a genre corresponding to a maximum probability among the probabilities as the genre of the image. 
     The controller of the display device according to an embodiment of the present disclosure may maintain the genre of the image as current genre when the maximum probability is less than or equal to a reference probability. 
     The display device according to an embodiment of the present disclosure may further comprise a user input interface configured to receive an image mode selection command, wherein the controller is configured to control the display unit to change the picture quality of the image according to the genre of the image when the image mode is set to an auto mode according to the image mode selection command. 
     [Advantageous Effects] 
     According to the embodiments of the present disclosure, the picture quality is automatically changed according to genres of images, thereby providing the optimal picture quality for images the user is currently watching, and minimizing the inconvenience of the user having to manually change the picture quality according to the images. 
     In addition, when the picture quality is changed, the picture quality is gradually changed for a set time, thus minimizing interference with the user&#39;s image viewing due to the change in the picture quality. 
     In addition, it is possible to minimize unnecessary change in picture quality by minimizing the change in picture quality when a user continuously switches channels or when an advertisement is displayed in the middle of broadcasting. 
     In addition, it is possible to provide a picture quality suitable for the genre of images by more accurately discriminating the genres of images by using an EPG, an audio signal, and a video signal, thus improving the reliability of the product. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG. 1  is a block diagram illustrating a configuration of a display device according to an embodiment of the present invention. 
         FIG. 2  is a block diagram illustrating a remote control device according to an embodiment of the present invention. 
         FIG. 3  is a view illustrating an actual configuration of a remote control device according to an embodiment of the present invention. 
         FIG. 4  is a view of utilizing a remote control device according to an embodiment of the present invention. 
         FIG. 5  is an exemplary diagram of a method for setting an image mode in a display device according to an embodiment of the present disclosure. 
         FIG. 6  is a flowchart illustrating a method for automatically changing a picture quality according to images in a display display according to an embodiment of the present disclosure. 
         FIG. 7  is a flowchart illustrating a method for acquiring a genre of an image in a display device according to an embodiment of the present disclosure. 
         FIG. 8  is an exemplary diagram illustrating a method for analyzing a type of an image based on a video signal in a display device according to an embodiment of the present disclosure. 
         FIG. 9  is a graph illustrating a change in picture quality when a display device according to an embodiment of the present disclosure changes a picture quality. 
     
    
    
     MODE FOR INVENTION 
     Hereinafter, embodiments relating to the present invention will be described in detail with reference to the accompanying drawings. The suffixes “unit” for components used in the description below are assigned or mixed in consideration of easiness in writing the specification and do not have distinctive meanings or roles by themselves. 
     Terms including ordinal numbers such as first and second may be used to describe various elements, but the elements are not limited by the terms. The terms are only used for the purpose of distinguishing one component from another component. 
       FIG. 1  is a block diagram illustrating a configuration of a display device according to an embodiment of the present invention. 
     Referring to  FIG. 1 , a display device  100  can include a broadcast reception unit  130 , an external device interface unit  135 , a storage unit  140 , a user input interface unit  150 , a controller  170 , a wireless communication unit  173 , a display unit  180 , an audio output unit  185 , and a power supply unit  190 . 
     The broadcast reception unit  130  can include a tuner  131 , a demodulation unit  132 , and a network interface unit  133 . 
     The tuner  131  can select a specific broadcast channel according to a channel selection command. The tuner  131  can receive broadcast signals for the selected specific broadcast channel. 
     The demodulation unit  132  can divide the received broadcast signals into video signals, audio signals, and broadcast program related data signals and restore the divided video signals, audio signals, and data signals to an output available form. 
     The network interface unit  133  can provide an interface for connecting the display device  100  to a wired/wireless network including internet network. The network interface unit  133  can transmit or receive data to or from another user or another electronic device through an accessed network or another network linked to the accessed network. 
     The network interface unit  133  can access a predetermined webpage through an accessed network or another network linked to the accessed network. That is, it can transmit or receive data to or from a corresponding server by accessing a predetermined webpage through network. 
     Then, the network interface unit  133  can receive contents or data provided from a content provider or a network operator. That is, the network interface unit  133  can receive contents such as movies, advertisements, games, VODs, and broadcast signals, which are provided from a content provider or a network provider, through network and information relating thereto. 
     Additionally, the network interface unit  133  can receive firmware update information and update files provided from a network operator and transmit data to an internet or content provider or a network operator. 
     The network interface unit  133  can select and receive a desired application among applications open to the air, through network. 
     The external device interface unit  135  can receive an application or an application list in an adjacent external device and deliver it to the controller  170  or the storage unit  140 . 
     The external device interface  135  can provide a connection path between the display device  100  and an external device. The external device interface  135  can receive at least one of image and audio outputted from an external device that is wirelessly or wiredly connected to the display device  100  and deliver it to the control unit. The external device interface unit  135  can include a plurality of external input terminals. The plurality of external input terminals can include an RGB terminal, at least one High Definition Multimedia Interface (HDMI) terminal, and a component terminal. 
     An image signal of an external device inputted through the external device interface unit  135  can be outputted through the display unit  180 . A sound signal of an external device inputted through the external device interface unit  135  can be outputted through the audio output unit  185 . 
     An external device connectable to the external device interface unit  130  can be one of a set-top box, a Blu-ray player, a DVD player, a game console, a sound bar, a smartphone, a PC, a USB Memory, and a home theater system but this is just exemplary. 
     Additionally, some content data stored in the display device  100  can be transmitted to a user or an electronic device, which is selected from other users or other electronic devices pre-registered in the display device  100 . 
     The storage unit  140  can store signal-processed image, voice, or data signals stored by a program in order for each signal processing and control in the controller  170 . 
     Additionally, the storage unit  140  can perform a function for temporarily store image, voice, or data signals outputted from the external device interface unit  135  or the network interface unit  133  and can store information on a predetermined image through a channel memory function. 
     The storage unit  140  can store an application or an application list inputted from the external device interface unit  135  or the network interface unit  133 . 
     The display device  100  can play content files (for example, video files, still image files, music files, document files, application files, and so on) stored in the storage unit  140  and provide them to a user. 
     The user input interface unit  150  can deliver signals inputted from a user to the controller  170  or deliver signals from the controller  170  to a user. For example, the user input interface unit  150  can receive or process control signals such as power on/off, channel selection, and screen setting from the remote control device  200  or transmit control signals from the controller  170  to the remote control device  200  according to various communication methods such as Bluetooth, Ultra Wideband (WB), ZigBee, Radio Frequency (RF), and IR. 
     Additionally, the user input interface unit  150  can deliver, to the controller  170 , control signals inputted from local keys (not shown) such as a power key, a channel key, a volume key, and a setting key. 
     Image signals that are image-processed in the controller  170  can be inputted to the display unit  180  and displayed as an image corresponding to corresponding image signals. Additionally, image signals that are image-processed in the controller  170  can be inputted to an external output device through the external device interface unit  135 . 
     Voice signals processed in the controller  170  can be outputted to the audio output unit  185 . Additionally, voice signals processed in the controller  170  can be inputted to an external output device through the external device interface unit  135 . 
     Besides that, the control module  170  can control overall operations in the display device  100 . 
     Additionally, the controller  170  can control the display device  100  by a user command or internal program inputted through the user input interface unit  150  and download a desired application or application list into the display device  100  in access to network. 
     The controller  170  can output channel information selected by a user together with processed image or voice signals through the display unit  180  or the audio output unit  185 . 
     Additionally, according to an external device image playback command received through the user input interface unit  150 , the controller  170  can output image signals or voice signals of an external device such as a camera or a camcorder, which are inputted through the external device interface unit  135 , through the display unit  180  or the audio output unit  185 . 
     Moreover, the controller  170  can control the display unit  180  to display images and control broadcast images inputted through the tuner  131 , external input images inputted through the external device interface unit  135 , images inputted through the network interface unit, or images stored in the storage unit  140  to be displayed on the display unit  180 . In this case, an image displayed on the display unit  180  can be a still image or video and also can be a 2D image or a 3D image. 
     Additionally, the controller  170  can play content stored in the display device  100 , received broadcast content, and external input content inputted from the outside, and the content can be in various formats such as broadcast images, external input images, audio files, still images, accessed web screens, and document files. 
     Moreover, the wireless communication unit  173  can perform a wired or wireless communication with an external electronic device. The wireless communication unit  173  can perform short-range communication with an external device. For this, the wireless communication unit  173  can support short-range communication by using at least one of Bluetooth™, 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  173  can support wireless communication between the display device  100  and a wireless communication system, between the display device  100  and another display device  100 , or between networks including the display device  100  and another display device  100  (or an external server) through wireless area networks. The wireless area networks can be wireless personal area networks. 
     Herein, the other display device  100  can be a mobile terminal such as a wearable device (for example, a smart watch, a smart glass, and a head mounted display (HMD)) or a smartphone, which is capable of exchanging data (or inter-working) with the display device  100 . The wireless communication unit  173  can detect (or recognize) a communicable wearable device around the display device  100 . Furthermore, if the detected wearable device is a device authenticated to communicate with the display device  100 , the controller  170  can transmit at least part of data processed in the display device  100  to the wearable device through the wireless communication unit  173 . Accordingly, a user of the wearable device can use the data processed in the display device  100  through the wearable device. 
     The display unit  180  can convert image signals, data signals, or OSD signals, which are processed in the controller  170 , or images signals or data signals, which are received in the external device interface unit  135 , into R, G, and B signals to generate driving signals. 
     Furthermore, the display device  100  shown in  FIG. 1  is just one embodiment of the present invention and thus, some of the components shown can be integrated, added, or omitted according to the specification of the actually implemented display device  100 . 
     That is, if necessary, two or more components can be integrated into one component or one component can be divided into two or more components and configured. Additionally, a function performed by each block is to describe an embodiment of the present invention and its specific operation or device does not limit the scope of the present invention. 
     According to another embodiment of the present invention, unlike  FIG. 1 , the display device  100  can receive images through the network interface unit  133  or the external device interface unit  135  and play them without including the tuner  131  and the demodulation unit  132 . 
     For example, the display device  100  can be divided into an image processing device such as a set-top box for receiving broadcast signals or contents according to various network services and a content playback device for playing contents inputted from the image processing device. 
     In this case, an operating method of a display device according to an embodiment of the present invention described below can be performed by one of the display device described with reference to  FIG. 1 , an image processing device such as the separated set-top box, and a content playback device including the display unit  180  and the audio output unit  185 . 
     Then, referring to  FIGS. 2 and 3 , a remote control device is described according to an embodiment of the present invention. 
       FIG. 2  is a block diagram illustrating a remote control device according to an embodiment of the present invention and  FIG. 3  is a view illustrating an actual configuration of a remote control device according to an embodiment of the present invention. 
     First, referring to  FIG. 2 , a remote control device  200  can 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 . 
     Referring to  FIG. 2 , the wireless communication unit  225  transmits/receives signals to/from an arbitrary any one of display devices according to the above-mentioned embodiments of the present invention. 
     The remote control device  200  can include an RF module  221  for transmitting/receiving signals to/from the display device  100  according to the RF communication standards and an IR module  223  for transmitting/receiving signals to/from the display device  100  according to the 
     IR communication standards. Additionally, the remote control device  200  can include a Bluetooth module  225  for transmitting/receiving signals to/from the display device  100  according to the Bluetooth communication standards. Additionally, the remote control device  200  can include an NFC module  227  for transmitting/receiving signals to/from the display device  100  according to the Near Field Communication (NFC) communication standards and a WLAN module  229  for transmitting/receiving signals to/from the display device  100  according to the Wireless LAN (WLAN) communication standards. 
     Additionally, the remote control device  200  can transmit signals containing information on a movement of the remote control device  200  to the display device  100  through the wireless communication unit  220 . 
     Moreover, the remote control device  200  can receive signals transmitted from the display device  100  through the RF module  221  and if necessary, can transmit a command on power on/off, channel change, and volume change to the display device  100  through the IR module  223 . 
     The user input unit  230  can be configured with a keypad button, a touch pad, or a touch screen. A user can manipulate the user input unit  230  to input a command relating to the display device  100  to the remote control device  200 . If the user input unit  230  includes a hard key button, a user can input a command relating to the display device  100  to the remote control device  200  through the push operation of the hard key button. This will be described with reference to  FIG. 3 . 
     Referring to  FIG. 3 , the remote control device  200  can include a plurality of buttons. The plurality of buttons can include a fingerprint recognition button  212 , a power button  231 , a home button  232 , a live button  233 , an external input button  234 , a voice adjustment button  235 , a voice recognition button  236 , a channel change button  237 , a check button  238 , and a back button  239 . 
     The fingerprint recognition button  212  can be a button for recognizing a user&#39;s fingerprint. According to an embodiment of the present invention, the fingerprint recognition button  212  can perform a push operation and receive a push operation and a fingerprint recognition operation. The power button  231  can be button for turning on/off the power of the display device  100 . The power button  232  can be button for moving to the home screen of the display device  100 . The live button  233  can be a button for displaying live broadcast programs. The external input button  234  can be button for receiving an external input connected to the display device  100 . The voice adjustment button  235  can be button for adjusting the size of a volume outputted from the display device  100 . The voice recognition button  236  can be a button for receiving user&#39;s voice and recognizing the received voice. The channel change button  237  can be a button for receiving broadcast signals of a specific broadcast channel. The check button  238  can be a button for selecting a specific function and the back button  239  can be a button for returning to a previous screen. 
     Again,  FIG. 2  is described. 
     If the user input unit  230  includes a touch screen, a user can touch a soft key of the touch screen to input a command relating to the display device  100  to the remote control device  200 . Additionally, the user input unit  230  can include various kinds of input means manipulated by a user, for example, a scroll key and a jog key, and this embodiment does not limit the scope of the present invention. 
     The sensor unit  240  can include a gyro sensor  241  or an acceleration sensor  243  and the gyro sensor  241  can sense information on a movement of the remote control device  200 . 
     For example, the gyro sensor  241  can sense information on an operation of the remote control device  200  on the basis of x, y, and z axes and the acceleration sensor  243  can sense information on a movement speed of the remote control device  200 . Moreover, the remote control device  200  can further include a distance measurement sensor and sense a distance with respect to the display unit  180  of the display device  100 . 
     The output unit  250  can output image or voice signals corresponding to a manipulation of the user input unit  235  or corresponding to signals transmitted from the display device  100 . A user can recognize whether the user input unit  235  is manipulated or the display device  100  is controlled through the output unit  250 . 
     For example, the output unit  250  can include an LED module  251  for flashing, a vibration module  253  for generating vibration, a sound output module  255  for outputting sound, or a display module  257  for outputting an image, if the user input unit  235  is manipulated or signals are transmitted/received to/from the display device  100  through the wireless communication unit  225 . 
     Additionally, the power supply unit  260  supplies power to the remote control device  200  and if the remote control device  200  does not move for a predetermined time, stops the power supply, so that power waste can be reduced. The power supply unit  260  can resume the power supply if a predetermined key provided at the remote control device  200  is manipulated. 
     The storage unit  270  can store various kinds of programs and application data necessary for a control or operation of the remote control device  200 . If the remote control device  200  transmits/receives signals wirelessly through the display device  100  and the RF module  221 , the remote control device  200  and the display device  100  transmits/receives signals through a predetermined frequency band. 
     The control unit  280  of the remote control device  200  can store, in the storage unit  270 , information on a frequency band for transmitting/receiving signals to/from the display device  100  paired with the remote control device  200  and refer to it. 
     The control unit  280  controls general matters relating to a control of the remote control device  200 . The control unit  280  can transmit a signal corresponding to a predetermined key manipulation of the user input unit  235  or a signal corresponding to a movement of the remote control device  200  sensed by the sensor unit  240  to the display device  100  through the wireless communication unit  225 . 
     Additionally, the voice acquisition unit  290  of the remote control device  200  can obtain voice. 
     The voice acquisition unit  290  can include at least one microphone  291  and obtain voice through the microphone  291 . 
     Then,  FIG. 4  is described. 
       FIG. 4  is a view of utilizing a remote control device according to an embodiment of the present invention. 
       FIG. 4A  illustrates that a pointer  205  corresponding to the remote control device  200  is displayed on the display unit  180 . 
     A user can move or rotate the remote control device  200  vertically or horizontally. The pointer  205  displayed on the display unit  180  of the display device  100  corresponds to a movement of the remote control device  200 . Since the corresponding pointer  205  is moved and displayed according to a movement on a  3 D space as show in the drawing, the remote control device  200  can be referred to as a spatial remote controller. 
       FIG. 4B  illustrates that if a user moves the remote control device  200 , the pointer  205  displayed on the display unit  180  of the display device  100  is moved to the left in correspondence thereto. 
     Information on a movement of the remote control device  200  detected through a 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 on the movement of the remote control device  200 . The display device  100  can display the pointer  205  to match the calculated coordinates. 
       FIG. 4C  illustrates that while a specific button in the remote control device  200  is pressed, a user moves the remote control device  200  away from the display unit  180 . Thus, a selection area in the display unit  180  corresponding to the pointer  205  can be zoomed in and displayed largely. 
     On the other hand, if a user moves the remote control device  200  close to the display unit  180 , a selection area in the display unit  180  corresponding to the pointer  205  can be zoomed out and displayed reduced. 
     On the other hand, if the remote control device  200  is away from the display unit  180 , a selection area can be zoomed out and if the remote control device  200  is close to the display unit  180 , a selection area can be zoomed in. 
     Additionally, if a specific button in the remote control device  200  is pressed, the recognition of a vertical or horizontal movement can be excluded. That is, if the remote control device  200  is moved away from or close to the display unit  180 , the up, down, left, or right movement can not be recognized and only the back and fourth movement can be recognized. While a specific button in the remote control device  200  is not pressed, only the pointer  205  is moved according to the up, down, left or right movement of the remote control device  200 . 
     Moreover, the moving speed or moving direction of the pointer  205  can correspond to the moving speed or moving direction of the remote control device  200 . 
     Furthermore, a pointer in this specification means an object displayed on the display unit  180  in correspondence to an operation of the remote control device  200 . Accordingly, besides an arrow form displayed as the pointer  205  in the drawing, various forms of objects are possible. For example, the above concept includes a point, a cursor, a prompt, and a thick outline. Then, the pointer  205  can be displayed in correspondence to one point of a horizontal axis and a vertical axis on the display unit  180  and also can be displayed in correspondence to a plurality of points such as a line and a surface. 
       FIG. 5  is an exemplary diagram of a method for setting an image mode in a display device according to an embodiment of the present disclosure. 
     The controller  170  may control the display unit  180  such that the display unit  180  displays an image mode setting screen. 
     The image mode setting screen may be a screen for setting a picture quality of images being displayed by the display unit  180 . 
     The image mode setting screen may include a plurality of image mode items. For example, as shown in  FIG. 5 , the video mode setting may include at least one of a ‘clear image’ mode, a ‘standard image’ mode, an ‘eco’ mode, a ‘movie’ mode, a ‘sport’ mode, a ‘game’ mode and an ‘auto’ mode. 
     The ‘clear Image’ mode is a mode for displaying a screen clearly by increasing the contrast, brightness, and sharpness of the screen, the ‘standard Image’ mode is a mode for displaying a screen with general contrast, brightness, and sharpness, the ‘eco’ code is a mode for adjusting a brightness of the screen to reduce power consumption, the ‘movie’ mode is a mode for displaying a screen optimized for a movie, the ‘sport’ mode is a mode for displaying a screen optimized for sports, in which a clear screen is implemented even in fast movement such as such as the case of kicking or throwing a ball, the ‘game’ mode is a mode for displaying on a screen optimized for the game, and the ‘auto’ mode is a mode in which picture quality is automatically changed according to an image. 
     Meanwhile, the image mode items shown in  FIG. 5  are given as examples for convenience of description, and the number, types, and names of the image mode items may be different from those shown in  FIG. 5 . 
     A user may select an image mode to display a screen with a desired picture quality through the image mode setting screen. 
     The controller  170  may receive an image mode selection command through the user input interface unit  150 . 
     The controller  170  may set an image mode by receiving a command to select any one of a plurality of image mode items. 
     In particular, when the image mode is set to the ‘auto’ mode through the image mode setting screen, the controller  170  may control the display unit  180  to automatically change a picture quality according to the genre of images. 
     That is, according to an embodiment, when the image mode is set to the ‘auto’ mode, the controller  170  may automatically change the picture quality according to the genre of images. 
     According to another embodiment, the controller  170  may automatically change the picture quality according to the genre of images without providing a separate image mode setting screen. 
       FIG. 6  is a flowchart illustrating a method for automatically changing a picture quality according to images in a display display according to an embodiment of the present disclosure. 
     The controller  170  may acquire the genre of images at preset periods (S 11 ). 
     The controller  170  may receive an image signal through the broadcast reception unit  130 , the external device interface unit  135 , the wireless communication unit  173 , and the like, and control the display unit  180  to display an image corresponding to the input image signal. 
     The controller  170  may acquire the genre of an image being displayed by the display unit  180  at preset periods. 
     The genre of the image may mean the type of the image. For example, the type of image may include movies, sports, games, animation, photo, drama, entertainment, documentary, and the like. In this case, the controller  170  may acquire the genre of the image as any one of movies, sports, games, animation, photo, drama, entertainment, documentary, and the like. 
     The controller  170  may acquire an EPG, an audio signal, and a video signal from the input image signal, and acquire a genre of the image based on at least one of the EPG, the audio signal, and the video signal. 
       FIG. 7  is a flowchart illustrating a method for acquiring a genre of an image in a display device according to an embodiment of the present disclosure. 
     The controller  170  may separate metadata, the audio signal, and the video signal from an image signal (S 101 ). 
     The image signal may include at least one of metadata, an audio signal, and a video signal. 
     Here, the meta data may refer to attribute information of an image signal, and may include an Electronic Program Guide (EPG). The EPG may include information such as a time, a title, a channel, and a genre of a broadcast program. 
     The audio signal is a signal in an audio range, and may be obtained by converting voice and all natural sounds in an audible frequency range into an electrical waveform signal. 
     The video signal is a signal for reporting the color, brightness, position, and the like of each pixel on the screen, and may be an electrical image signal obtained by converting a moving image taken by a camera or the like into an electrical waveform signal. 
     The controller  170  may separate the input image signal into the metadata, the audio signal, and the video signal using a decoder (not shown). 
     The controller  170  may determine whether the genre of the image is detectable from the metadata (S 103 ). 
     When the EPG includes the genre of the image, the controller  170  may determine that the genre of the image is detectable from the metadata. 
     On the other hand, when the EPG does not include the genre of the image, the controller  170  may determine that the genre of the image is undetectable from the metadata. 
     When the genre of the image is detectable from the metadata, the controller  170  may acquire the genre of the image based on the metadata (S 105 ). 
     Meanwhile, when the genre of the image undetectable from the metadata, the controller  170  may acquire the genre of the image based on at least one of the audio signal and the video signal. 
     Specifically, the controller  170  may analyze the audio signal to classify the type of image (S 107 ), and analyze the video signal to classify the type of the image (S 109 ). 
     Although it is illustrated that step S 109  is performed after step S 107  has been performed in  FIG. 7 , the order of steps S 107  and S 109  may be changed or steps S 107  and S 109  may be performed simultaneously. 
     The controller  170  may acquire the type of image based on the audio signal. For example, the controller  170  may classify the type of image into news, movie, music, standard, or the like based on the audio signal. Specifically, the controller  170  may classify the type of the image as news when a human voice of the audio signal is recognized as having a magnitude within a predetermined range for a certain period of time or longer, classify the type of the image as movies when a human voice, sound effect, and the like are mixed in the audio signal, classify the type of the image as music when the audio signal includes a melody, and classify the type of the image as standard when the audio signal does not belong to any one of news, movie, and music. 
     The controller  170  may analyze the type of the image based on the video signal. For example, the controller  170  may classify types of images into cartoons, movies, dramas, sports, and the like based on the video signal. Specifically, the controller  170  may classify the type of the image as a cartoon when the video signal contains more than the set standard of secondary color, classify the type of the image as a movie or a drama according to the resolution of the image when a human being is detected from the video signal, and classify the type of image as sports when movement of people in a certain place is detected from the video signal. 
       FIG. 8  is an exemplary diagram illustrating a method for analyzing a type of an image based on a video signal in a display device according to an embodiment of the present disclosure. 
     The minimum information for the controller  170  to classify the genre of an image based on the video signal may be brightness and hue information of the image. 
     Specifically, the controller  170  may acquire one frame for every n frames of the video signal. For example, the controller  170  may acquire an n-th frame image  801 , a 2n-th frame image  802 , a 3n-th frame image  803 , a 4n-th frame image  804 , and the like from the video signal. 
     The controller  170  may acquire first to fourth clipping images  801   a,    802   a,    803   a,  and  804   a  by cutting out only a partial region from a plurality of frame images  801  to  804 , respectively. In this case, the first clipping image  801   a  may be an image converted into the YCbCr color space, and each of the second to fourth clipping images  802   a,    803   a,  and  804   a  may be an image expressed only by “Y” (brightness component). After extracting only color difference information (Cb, Cr) from the first clipping image  801   a,  the controller  170  may acquire an image  801   b  expressed with hues and an image  801   c  expressed with saturation, and an image  801   d  expressed only with a brightness component Y. In addition, the type of the image may be analyzed based on the hue image  801   b,  the saturation image  801   c,  and the brightness image  801   d  extracted from the first frame image  801 , and the brightness images  802   a,    803   a,  and  804   a  respectively extracted from the second to fourth frame images  802  to  804 . 
     That is, after acquiring specific frame images from the image, the controller  170  may analyze the type of image based on changes in hue, saturation, and brightness of the frame images. 
     Meanwhile, the method of analyzing the type of image shown in  FIG. 8  is merely exemplary, and the controller  170  may analyze the type of the image through various methods. 
     For example, the controller  170  may analyze the type of image in consideration of high-frequency components, motion components, a frequency of scene change, text information, and the like, in addition to the brightness and hue information of images. 
     Again, description will be given with reference to  FIG. 7 . 
     The controller  170  may calculate a probability for each genre based on the result of classifying the types of images (S 111 ). 
     The controller  170  may calculate a probability that an image corresponds to each of a plurality of genres. For example, the controller  170  may classify the type of image as a movie as a result of analyzing the audio signal, and calculate the probability that the genre of the image is a movie as 18% and the probability that the genre of the image is sports as 20% when the type of image is classified as the movie and sports as the result of the analysis for the video signal. 
     According to an embodiment, the controller  170  may give a weight to any one of the audio signal and the video signal, and in this case, the probabilities for genres may be calculated differently. 
     That is, since the method of calculating a probability for each genre is merely exemplary, the method may be various. 
     The controller  170  may determine whether the maximum probability exceeds a reference probability (S 113 ). 
     The maximum probability may mean a probability having the largest value among the calculated probabilities for genres. 
     The reference probability may be a predetermined probability to increase reliability of genre acquisition. For example, the reference probability may be 70%. 
     When the maximum probability is greater than the reference probability, the controller  170  may recognize the genre of the image as the genre having the maximum probability (S 115 ), and when the maximum probability is less than or equal to the reference probability, maintain the genre of the image as a current genre (S 117 ). 
     For example, when the probability that the image is a movie is 80% and the probability that the image is sports is 80% as the result of calculation of the probabilities for genres, the maximum probability of 80% is greater than the reference probability of 70%, and thus the controller 170 may recognize, as a genre, a movie corresponding to the maximum probability of 80%. 
     On the other hand, as another example, when the probability that the image is a movie is 50%, the probability that the image is drama is 25%, and the probability that the image is news is 25%, as the result of calculation of the probabilities for genres, the maximum probability of 50% is less than or equal to the reference probability of 70%, and thus the controller  170  may maintain, as a genre of the image, the current genre. That is, when the maximum probability is less than or equal to the reference probability, the controller  170  may continue to maintain the current genre of the image without changing the genre of the image. For example, when the current genre of the current is sports, the genre of the image may be maintained as sports. 
     As described with reference to  FIG. 7 , when the genre of the image is able to be detected through the EPG, the controller  170  may recognize a genre included in the EPG as the genre of the image. Since the EPG is provided by a broadcasting station, when a genre is included in the EPG, the genre recognition accuracy according to the EPG is higher than the genre recognition accuracy according to the audio signal or the video signal. Meanwhile, when the genre cannot be obtained from the EPG, the controller  170  may recognize the genre by extracting features from at least one of the audio signal and the video signal. 
     Meanwhile, according to an embodiment, the controller  170  may transmit at least one of the audio signal and the video signal to an external server (not shown), and in this case, the external server (not shown) may be a server capable of learning a method of classifying a genre according to an audio signal and a video signal based on a database. In this case, the controller  170  may receive the genre of an image from the external server (not shown). 
     As described above, the controller  170  may acquire the genre of the image in various methods. 
     Again, details will be described with reference to  FIG. 6 . 
     After acquiring the genre of the image, the controller  170  may set a target picture quality according to the acquired genre (S 13 ). 
     The controller  170  may change the picture quality to a picture quality corresponding to the genre of the image. 
     Specifically, the storage unit  140  may store a picture quality for each of genres of images, and the picture quality may include at least one of contrast, brightness, sharpness, color depth, and color temperature. For example, the storage unit  140  may store picture quality information including a contrast of 95, a brightness of 50, a sharpness of 25, a color depth of 55, and a color temperature of 20 when the genre of the image is ‘movie’, picture quality information including a contrast of 100, a brightness of 50, a sharpness of 30, a color depth of 70, and a color temperature of 50 when the genre of the image is ‘sports’, picture quality information including a contrast of 80, a brightness of 70, a sharpness of 15, a color depth of 60, and a color temperature of 40 when the genre of the image is ‘news’, but the present disclosure is not limited thereto as they are merely examples. 
     The controller  170  may set the picture quality according to the acquired genre as a target picture quality. For example, when ‘movie’ is acquired as the genre of the image, the controller  170  may set the target picture quality to a contrast of 95, a brightness of 50, a sharpness of 25, a color depth of 55, and a color temperature of 20. 
     After setting the target picture quality, the controller  170  may control the display unit  180  to change the picture quality from the current picture quality to the target picture quality. The current picture quality may mean the picture quality of an image currently being displayed by the display unit  180 . The controller  170  may increase the picture quality when the target picture quality is higher than the current picture quality, and may decrease the picture quality when the target picture quality is lower than the current picture quality. 
     Meanwhile, there may be various methods for the controller  170  to change the picture quality to the target picture quality. 
     According to an embodiment, the controller  170  may control the display unit  180  to immediately change the picture quality from the current picture quality to the target picture quality. 
     According to another embodiment, the controller  170  may control the display unit  180  such that the picture quality is gradually changed during a set time. Hereinafter, a method of gradually changing a picture quality of an image will be described. 
     The controller  170  may determine whether a target picture quality is greater than a current picture quality (S 15 ). 
     The controller  170  may compare the target picture quality with the current picture quality to determine whether the target picture quality is higher than the current picture quality. 
     When the target picture quality is lower than the current picture quality, the controller  170  may set a picture quality adjustment variable to −1 (decrement) (S 17 ), and when the target picture quality is higher than the current picture quality, set the picture quality adjustment variable to +1 (increment) (S 19 ). 
     The picture quality adjustment variable may mean a picture quality adjustment direction. When the target picture quality is higher than the current picture quality, the controller  170  may set a picture quality adjustment direction variable to a positive value, and when the target picture quality is lower than the current picture quality, the picture quality adjustment direction variable to a negative value. 
     In the example of  FIG. 6 , it is assumed that the picture quality adjustment variable is set to +1 or −1, but this is only an example for convenience of description, and thus is not limited thereto. The controller  170  may increase a picture quality change rate of images by increasing the absolute value of the picture quality adjustment variable, and decrease the picture quality change rate of images by decreasing the absolute value of the picture quality adjustment variable. The controller  170  may receive the picture quality change rate of images through the user input interface unit  150 , and in this case, may change the absolute value of the picture quality adjustment variable according to the picture quality change rate. 
     When the picture quality adjustment variable is a negative number, the picture quality may be changed to be lower, and when the picture quality adjustment variable is a positive number, the picture quality may be changed to be higher. 
     The controller  170  may set a picture quality adjustment variable for each of elements constituting the picture quality. For example, when a target picture quality includes a contrast of 95, a brightness of 50, a sharpness of 25, a color depth of 55, and a color temperature of 20, and the current picture quality includes a contrast of 80, a brightness of 70, a sharpness of 25, a color depth of 55, and a color temperature of 40, the controller 170 may set the quality adjustment variable of the contrast to +1, the quality adjustment variable of the brightness to −1, and the quality adjustment variable of the color temperature to −1. 
     The controller  170  may change picture quality settings according to the picture quality adjustment variable (S 21 ). 
     The controller  170  may set a picture quality adjustment time, and may control the display unit  180  to change the picture quality in a stepwise manner from the current picture quality to the target picture quality during the picture quality adjustment time. 
     The picture quality adjustment time may be a time set to minimize the user&#39;s discomfort in viewing images due to a sudden change in picture quality. For example, the picture quality adjustment time may be 3 minutes, but is only an example and is not limited thereto. 
     The controller  170  may acquire a picture quality adjustment step by dividing a difference value between the target picture quality and the current picture quality by the picture quality adjustment time. For example, when the contrast corresponding to the target picture quality is 95 and the contrast corresponding to the current picture quality is 80, the controller 170 may perform an operation of dividing 15, which is the difference between the target picture quality and the current picture quality, by 3 minutes, which is the picture quality adjustment time, to obtain a picture quality adjustment step of 0.08. Although only the contrast is given as an example, the controller  170  may obtain the picture quality adjustment step for each of the elements constituting the picture quality. The picture quality adjustment step may be different depending on the elements constituting the picture quality. 
     The controller  170  may control the display unit  180  to change the picture quality through the product of the picture quality adjustment step and the picture quality adjustment variable. That is, the controller  170  may control the display unit  180  to change the picture quality by a value obtained by multiplying the picture quality adjustment step of 0.08 by the picture quality adjustment variable +1 or −1 at a time. The display unit  180  may display an image of which the picture quality setting has been changed by a value obtained by multiplying the picture quality adjustment step of 0.08 by the picture quality adjustment variable +1 or −1 from the current picture quality. 
     The controller  170  may determine whether the current picture quality is identical to the target picture quality (S 23 ). 
     When the current picture quality is not identical to the target picture quality, the controller  170  may change the picture quality settings according to the picture quality adjustment variable. That is, the controller  170  may change the picture quality settings of the display unit  180  until the current picture quality is identical to the target picture quality. 
     Meanwhile, when the current picture quality is identical to the target picture quality, the controller  170  may maintain the current picture quality (S 25 ). 
     That is, when the current picture quality is identical to the target picture quality, the controller  170  may stop changing the picture quality. 
       FIG. 9  is a graph illustrating a change in picture quality when a display device according to an embodiment of the present disclosure changes a picture quality. 
     Referring to  FIG. 9 , the controller  170  may set a target picture quality at time point t 1  and set a picture quality adjustment time to a time (t 2 −t 1 ). The controller  170  may calculate a picture quality adjustment step based on the difference between the target picture quality and the current picture quality and the time (t 2 −t 1 ). 
     The controller  170  may gradually change the picture quality during a period of time from time point t 1  to time point t 2 . The controller  170  may set the picture quality such that the picture quality is changed every second by the amount corresponding to the picture quality adjustment step. Accordingly, the picture quality being displayed by the display unit  180  may be gradually changed. Accordingly, it is possible to minimize a case in which the user recognizes the change in picture quality, so that the picture quality can be changed more naturally. 
     Meanwhile, the controller  170  may fix the genre of the image during the picture quality adjustment time. That is, the controller  170  may not change the genre of the image during the picture quality adjustment time. 
     This may be to minimize an unnecessary change in picture quality. As a specific example, when the display unit  180  displays a specific program, there is a case in which a commercial is temporarily displayed in the middle of the program. In this case, the controller  170  may recognize that the genre of images has been changed while the commercial is being displayed. In this case, when the picture quality is changed based on a genre changed according to the commercial, after the commercial ends, the picture quality is changed according to the genre according to the program, thus causing a problem of continuously changing the picture quality for a short period of time. Accordingly, the controller  170  may minimize unnecessary changes in picture quality by fixing the genre of the image during the picture quality adjustment time. 
     Further, according to an embodiment, after acquiring the genre of images in step S 11 , the controller  170  may immediately set a target picture quality and change the picture quality to the target picture quality. 
     However, according to another embodiment, after acquiring the genre of images in step S 11 , the controller  170  may set the target picture quality according to the genre of images only when the acquired genre of images is maintained for a predetermined time, and change the picture quality to the target picture quality. That is, when it is recognized that the genre of images is changed from a current genre to another genre after the genre of the image is acquired, the controller  170  may control the display unit  180  to change the picture quality only when the changed genre is maintained for a predetermined time. The reason for this is to change the picture quality only when it is recognized that the user continues to watch a specific channel, since continuously changing the picture quality even when the user simply switches channels corresponds to an unnecessary change in picture quality. 
     The display device  100  according to an embodiment of the present disclosure may automatically change a picture quality such as contrast, brightness, color temperature, or the like based on a change in EPG, audio signal, or video signal. 
     As described above, according to an embodiment of the present disclosure, the controller  170  may switch an audio mode to any one of a surround mode, a TV speaker mode, a Bluetooth speaker mode, and a speaker extension mode based on the genre or channel number of images to output a suitable sound source, thereby improving the user&#39;s satisfaction. 
     The above description is merely illustrative of the technical idea of the present disclosure, and various modifications and changes may be made thereto by those skilled in the art without departing from the essential characteristics of the present disclosure. 
     Therefore, the embodiments of the present disclosure are not intended to limit the technical spirit of the present disclosure but to illustrate the technical idea of the present disclosure, and the technical spirit of the present disclosure is not limited by these embodiments. 
     The scope of protection of the present disclosure should be interpreted by the appending claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present disclosure.