KR20100084247A - Display apparatus and control method thereof - Google Patents

Abstract

PURPOSE: A display device and a control method thereof are provided to automatically change a preset picture quality related value according to a state of an inputted test pattern inputted from an external image device. CONSTITUTION: A storage unit(204) stores a reference level value about each area of a test pattern signal. A level value detecting unit(203) detects a level value about each preset area by processing a test pattern signal inputted through a signal input unit(202). A control unit(205) sets an image quality related adjustment value according to a signal characteristic of a connected external image device(100).

Description

Display apparatus and control method thereof

The present invention relates to a display device, and more particularly, to a display device and a method of controlling the same, capable of automatically changing a predetermined picture quality value according to a signal characteristic of a currently connected external video device.

In general, a projection display device is configured to display an image signal supplied from an external image device. The external imaging device supplies image signals to the projection display device in a variety of forms.

That is, an external image device that supplies an image signal to the projection display device may include a PC, a DVD player, a VCR, and a game machine. Accordingly, as the type of the external image device varies, the characteristics of the image signal provided to the projection display device also vary. As a result, the image quality of the displayed image signal depends on the type of the external image device that supplies the image signal. Many differences will occur.

In the conventional projection display device, since image quality values cannot be set according to characteristics of all external image apparatuses, image quality values are set in accordance with standard signals, and image signals to which the set image quality values are applied are provided to the user.

In addition, in order to compensate for the difference in the image quality of the external image apparatus as described above, it is necessary to change various image quality related setting values so that the input image signal is displayed at the desired image quality. That is, the user may adjust the image quality of the input image signal by setting contrast, brightness, color, color density, and sharpness to a desired state so as to improve the image quality of the input image signal.

As described above, the image quality value set according to the signal characteristics of the currently connected external image apparatus is stored in the storage device, and an image to which the user applies the image quality value desired by the user may be displayed at any time.

However, in the related art, the user can directly set the image quality value according to the signal characteristics of the currently connected external video device, so that the input video signal can be displayed in an optimal screen state desired by the user. When the device is changed, it is inconvenient to change the preset image quality value according to the changed characteristics of the external video device.

According to an embodiment of the present invention, image quality-related values such as contrast, brightness, color, and color density may be automatically set to match the signal characteristics of the currently connected external video device.

In addition, according to an embodiment of the present invention, an image quality value corresponding to a signal characteristic of a currently connected external image device is automatically set, so that an image having an optimum image quality can be provided to a user.

The technical problems to be achieved in the proposed embodiment are not limited to the technical problems mentioned above, and other technical problems not mentioned above are clear to those skilled in the art to which the proposed embodiments belong from the following description. Can be understood.

According to an exemplary embodiment of the present invention, a display apparatus includes: a storage unit which stores a reference level value for each region of a test pattern signal; A signal input unit for receiving a test pattern signal from a connected external video device; A level value detector configured to signal-process a test pattern signal input through the signal input unit and detect a level value for each preset area; And a controller configured to set an image quality related adjustment value according to signal characteristics of the connected external video apparatus according to a difference between a level value for each region detected by the level value detector and a reference level value stored in the storage unit. It is composed.

In addition, the control method of the display apparatus according to an embodiment of the present invention includes the steps of outputting a reference test pattern signal to the connected external image device when the connection of the external image device is detected; Re-input of the output reference test pattern signal from the connected external video apparatus; Acquiring a level value for each preset area based on a reference test pattern signal input from the external image device; And setting at least one image quality related adjustment value based on at least a signal characteristic of the connected external video apparatus based on the obtained level value for each region.

According to an exemplary embodiment of the present invention, a display apparatus and a control method thereof automatically change a preset image quality-related value according to a state of a test pattern input from a currently connected external video device, thereby requiring a user to directly set a preset image quality-related value. In addition to solving the inconvenience, there is an effect that can provide an image of the optimum image quality suitable for the signal characteristics of the connected external video device.

The proposed embodiment will be described.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. However, the spirit of the present invention is not limited to the embodiments presented, and other inventions which are deteriorated by the addition, modification, deletion, etc. of other components, or other embodiments included within the scope of the present invention are easily made. I can suggest.

The term used in the present invention was selected as a general term widely used as possible, but in some cases, the term is arbitrarily selected by the applicant, in which case the meaning is described in detail in the description of the invention, the name of a simple term It should be clear that the present invention is to be understood as a meaning of terms.

In other words, in the following description, the word 'comprising' does not exclude the presence of other elements or steps than those listed.

1 is a diagram illustrating a configuration of a display apparatus according to an exemplary embodiment of the present invention.

As shown in FIG. 1, a display apparatus according to an exemplary embodiment of the present invention includes an external imaging apparatus 100 and a display apparatus.

Here, the external image device 100 and the display device 200 are connected through a separate cable. In this case, the external video device 100 and the display device 200 may be connected through a high definition multimedia interface (HDMI) cable. In addition to this, the external video device 100 and the display device may be DVI cables, S-Viedo cables. It will be apparent to those skilled in the art to which the present invention pertains.

In addition, the external imaging apparatus 100 and the display apparatus 200 may be connected through a wireless communication module. That is, the request data may be transmitted / received between the external video apparatus 100 and the display apparatus 200 through a Bluetooth communication means.

The external video device 100 transmits a video signal and an audio signal to the display device 300. The external video device 100 includes a digital versatile disc (DVD) player, a set top box, a VTR, and a game machine. And the like.

Accordingly, the external video device 100 includes a decoder, a data transmitter, a data receiver, and a controller, and includes a tuner or an optical pickup device according to a unique function of the external video device 100. And additional configurations.

The configuration of the external imaging apparatus 100 has been described above, and the configuration of the display apparatus 200 will be described below.

The display apparatus 200 corresponds to a digital television (DTV) or a monitor, and processes and outputs an image signal and an audio signal transmitted from the external video apparatus 100.

As illustrated in FIG. 1, the display apparatus 200 may test a signal output unit 201 for outputting a pre-stored reference test pattern signal to a connected external image apparatus 100 and a test from the connected external image apparatus 100. A signal input unit 202 for receiving a pattern signal, a level value detector 203 for detecting a level value for each region by signal processing a test pattern signal input through the signal input unit 202, and a test pattern The storage unit 204 stores the reference level value for each area of the signal, and the level value for each area detected through the level value detector 203 for each area stored in the storage unit 204. And a controller 205 for changing a preset quality-related adjustment value to match the reference level value.

The signal output unit 201 provides a test pattern signal previously stored in the storage unit 204 to an external video device currently connected.

Here, in order to check signal characteristics of an external video device, a test pattern signal may be input from an external video device to be connected, but when the test pattern signal is input from the connected external video device, the reference of the test pattern signal is used. Since the level value cannot be confirmed, the prestored test pattern signal is output to the external video device connected through the signal output unit 201.

The signal input unit 202 detects a connection of an external video device, and receives the output test pattern signal from the external video device in which the connection is detected.

That is, the signal input unit 202 receives a test pattern signal transmitted from an external video apparatus under the control of the controller 205 and outputs the test pattern signal to the level value detector 203.

The level value detector 203 obtains a level value for each preset area from the test pattern signal received through the signal input unit 202. Here, the level value detector 203 may be configured by a signal converter (not shown) for converting the received test pattern signal into a Y, Cb, or Cr signal, and the signal converter (not shown). And a signal processor (not shown) for signal-processing each converted signal and detecting a level value for each preset region.

In conclusion, the level value detector 203 converts the R, G, and B image signals input from the outside into Y, Cb, and Cr (YUV) signals by applying a color space conversion (CSC) algorithm.

Equation 1 is used to convert an R, G, B type video signal into a YUV type video signal in a 3 * 3 matrix.

That is, when converting the R, G, B type video signals into YUV type video signals, the color space conversion algorithm described in Equation 1 is applied, and the YUV type video signals are converted into R, G, B type signals. When converting to a video signal, a color space conversion algorithm is applied based on (A- ¹ ) instead of (A) described in Equation ( ¹ ).

In addition, the color space conversion algorithm of the 3 * 3 matrix as described above is already known in the technical field to which the present invention is detailed description thereof will be omitted.

In conclusion, the Color Space Algorithm (CSC) is a function that sets the coordinates of colors differently by converting an RGB signal into a YUV signal or inversely converting the converted YUV signal into an RGB signal.

The YUV was developed for analog video in PAL but is also commercially available for CCIR601, the European video standard in digital video. YUV is a color system in which the eye is most sensitive to light intensity. In this case, Y represents luminance and luminance, and U and V represent chromaticity. The RGB color coordinates have the following relationship.

Y = 0.299R + 0.587G + 0.114B

U = B-Y

V = R-Y

The level value detector 203 detects and transmits the level values of the designated regions from the converted Y, Cb, and Cr signals to the controller 205.

That is, as shown in Fig. 2, the test pattern signal is a color bar signal (color bar), which is a seven-color signal designed for testing a transceiver for color television, and this signal is a black and white image of seven steps. This is also called gray scale.

In general, the receiver can easily distinguish various important characteristics by the test pattern signal, thereby obtaining highly valid determination information including color purity, color gain, and white balance. The test pattern signal includes a color order color bar and a color order color bar commonly used in Europe.

 In addition, the level value detector 203 obtains level values for four areas in order to adjust brightness, contrast, and color, respectively. Here, the level value detector 203 acquires the level value of the Y signal, the level value of the Cb signal, and the level value of the Cr signal for the four areas, and controls the level value for each of the acquired areas. 205).

The storage unit 204 stores programs related to the operation of the display apparatus, various data generated during the operation of the display apparatus, and reference level value information for each region of the test pattern signal.

Here, the storage unit 204 is implemented as an EEPROM (Electrically Erasable Programmable Read-Only Memory), and is preferably connected to the control unit 205 according to the I2C scheme.

That is, the storage unit 204 has a reference level value of the Y signal for the first region 301 of the test pattern signal 300, a reference level value of the Y signal for the second region 302, and a second value. The reference level value of the Cb signal for the region 302, the reference level value of the Cb signal for the third region 303, the reference level value of the Cr signal for the second region 302, and the fourth region ( Reference level value information of the Cr signal for 304 is stored.

The controller 205 compares the level value of each region detected by the level value detector 203 with the reference level value pre-stored in the storage unit 204, and preset image quality according to the comparison result of the level values. Change the relevant adjustment value.

Here, the image quality-related adjustment values include Y offset, Y gain, Cb offset, Cb gain, Cr offset, and Cr gain values.

In this case, the difference between the offset and the gain is as follows.

y = a x + b

For example, when the relationship between the digital signal and the analog signal is equal to Equation 3, y is a digital conversion signal, x is an input analog signal, a means gain and b means offset.

The controller 205 uses the detected level value and the reference level value to adjust the Y offset value for brightness adjustment, the Y gain, Cb offset and Cr offset values for contrast adjustment, and the Cr gain for color adjustment. Change the Cb gain value.

That is, the controller 205 first measures the Y signal level value for the first region 301 which is the full black region of the test pattern signal 300, and the reference level of the Y signal for the first region to adjust the brightness. Compare the values, and if the two level values are different, selectively increase / decrease the preset Y offset value.

In other words, if the detected Y signal level value for the first region is less than the reference level value, the preset Y offset value is increased, and conversely, if the Y signal level value for the first region is greater than the reference level value, , Decrease the preset Y offset value.

In addition, the controller 205 adjusts the Y signal level value for the second region 302 which is the full white region of the test pattern signal 300, and the reference level of the Y signal for the second region to adjust the contrast. Compare the values and increase / decrease preset Y gain values so that the two level values match.

Similarly, the level values of the Cb and Cr signals of the second region 302 which is the full white region of the test pattern signal 300 and the reference level values of the Cb and Cr signals of the second region are compared. The Cb offset value and the Cr offset value are increased / decreased to match the two level values.

In addition, the controller 205 may adjust the Cb signal level value of the third region 303, which is a blue color region of the test pattern signal 300, and the Cb signal of the previously stored third region, to adjust the blue color. Compare the reference level values of and increase / decrease the preset Cb gain value to match the two level values.

In addition, similarly, the controller 205 may adjust the level of the Cr signal with respect to the fourth region 304, which is a red color region of the test pattern signal 300, and the previously stored fourth color to adjust the red color. The reference level value of the Cr signal for the region is compared, and the predetermined Cr gain value is increased / decreased to match the two level values.

The controller 205 may adjust the Y offset, Y gain, Cb offset, Cb gain, Cr offset, and Cr gain values according to the signal characteristics of the connected external image device as described above. The adjustment values are stored in the storage unit 204 corresponding to the product information of the device.

Accordingly, when the external video device having a previously connected history is reconnected, the controller 205 immediately applies the stored adjustment value without checking the quality related adjustment value.

As described above, the display apparatus according to an exemplary embodiment of the present invention automatically changes a preset image quality-related value according to a state of a test pattern input from a currently connected external video device, thereby making it difficult for a user to directly set a preset image quality-related value. In addition to solving this problem, it can provide an image with an optimum image quality suitable for the signal characteristics of the connected external video device.

In the control method of the display apparatus according to the exemplary embodiment of the present invention configured as described above, as shown in FIG. 3, first, it is determined whether a connection of an external video device is detected (S101). The determination of whether the external video device is connected may be performed by checking whether a predetermined voltage transmitted by the external video device is detected from a specific terminal of the external video device connection cable.

Subsequently, when the detection of the connection of the external video device is detected (S101), the prestored test pattern signal is output to the connected external video device (S102).

Then, the output test pattern signal is input again from the external video device (S103).

Subsequently, a level value for each region is obtained from the test pattern signal input from the external video apparatus (S104).

In operation S105, the level value obtained from the input test pattern signal is compared with a reference level value for each region. That is, it is determined whether the level value obtained from the input test pattern signal matches the reference level value input under normal conditions.

Subsequently, when the level value for each of the acquired regions and the reference level value for the respective regions are different from each other according to the comparison, the quality-related value is set such that the level value for each of the acquired regions coincides with the reference level value. It adjusts (S106).

Then, the adjusted image quality related value is stored corresponding to the product information of the connected external video device (S107).

Hereinafter, an operation of adjusting the quality related value will be described in more detail.

4 is a flowchart illustrating a method of adjusting brightness of a display apparatus in more detail.

As shown in FIG. 4, in the brightness adjusting method of the display apparatus, first, a test pattern signal input from the external video apparatus is converted into a digital signal having a Y, Cb, or Cr form (S201). That is, the input color space conversion algorithm is applied to convert the input analog video signal into a digital video signal.

Subsequently, a level value for the first region is obtained from the converted Y signal (S202). That is, the Y level value of the region where the full black image is located among the image regions existing in the test pattern signal is obtained.

In operation S203, it is determined whether the obtained Y level value for the first region is identical to a previously stored level value for the corresponding region.

Subsequently, if the obtained Y level value for the first region does not match a previously stored level value for the first region, the determination result (S203) determines whether the level value for the first region is greater than the reference level value. It is determined (S204).

If the obtained level value of the first region is greater than the reference level value, the determined Y offset value is decreased to match the two level values (S205).

In addition, if the obtained level value of the first region is greater than the reference level value (S204), the preset Y offset value is increased to match the two level values (S206).

Meanwhile, if the obtained Y level value for the first region coincides with a previously stored level value for the first region, the brightness adjustment process is terminated.

5 is a flowchart illustrating a method of adjusting contrast of a display apparatus in more detail.

As shown in FIG. 5, in the contrast adjusting method of the display apparatus, first, a test pattern signal input from the external video apparatus is converted into a digital image signal having Y, Cb, and Cr formats (S301).

Subsequently, a level value for the second region is obtained from the converted Y signal (S302). That is, the Y level value of the region where the full white image is located among the image regions existing in the test pattern signal is obtained.

In operation S303, it is determined whether the obtained Y level value for the second region is greater than a reference level value for the corresponding region.

Subsequently, when the Y level value for the second region is greater than the reference level value for the region, the determination result S303 decreases the Y gain such that the two values coincide with each other (S304).

In addition, if the Y level value for the second region is less than the reference level value for the region, the determination result (S303) increases the Y gain value so that the two values coincide (S305).

Subsequently, a level value for the second region is obtained from the converted Cb and Cr signals. That is, the Cb and Cr level values of the region where the full white image is located among the image regions existing in the test pattern signal are obtained (S306).

In operation S307, it is determined whether the obtained Cb and Cr level values of the second region are greater than the reference level values of the corresponding region.

Subsequently, when the obtained Cb and Cr level values for the second region are larger than the reference level values for the corresponding region, the Cb and Cr offset values are decreased to match the two level values (S308).

In addition, when the obtained Cb and Cr level values for the second region are smaller than the reference level values for the corresponding region, the Cb and Cr offset values are increased to match the two level values (S309).

6 is a flowchart illustrating a method of adjusting a color of a display apparatus in more detail.

As shown in FIG. 6, in the color adjusting method of the display apparatus, first, a test pattern signal input from the external video apparatus is converted into a digital image signal having Y, Cb, and Cr formats (S401).

Subsequently, a level value for the third region is obtained from the converted Cb signal (S402). That is, the Cb level value of the region where the blue image is located among the image regions existing in the test pattern signal is obtained.

In operation S403, it is determined whether the obtained Cb level value for the third region is greater than a reference level value for the corresponding region.

Subsequently, if the Cb level value for the acquired third region is greater than the reference level value for the corresponding region, the determination result (S403) decreases the Cb gain value to match the two level values (S404).

In addition, when the obtained Cb level value for the third region is smaller than the reference level value for the corresponding region, the determination result (S403) increases the Cb gain value to match the two level values (S405).

Subsequently, a level value for the fourth region is obtained from the converted Cr signal (S406). That is, the Cr level value of the region where the red image is located among the image regions existing in the test pattern signal is obtained.

In operation S407, it is determined whether the obtained Cr level value for the fourth region is greater than a reference level value for the corresponding region.

Subsequently, when the result of the determination (S407) is greater than the obtained Cr level value for the fourth region, the Cr gain value is reduced to match the two level values (S408).

In addition, if the obtained Cr level value for the fourth region is less than the reference level value for the corresponding region, the determination result (S407) increases the Cr gain value to match the two level values (S409).

The control method of the display apparatus according to an exemplary embodiment of the present invention automatically changes a preset image quality-related value according to a state of a test pattern input from a currently connected external video device, so that a user needs to set a preset image quality-related value. In addition to solving this problem, it can provide an image with an optimum image quality suitable for the signal characteristics of the connected external video device.

1 is a view showing the configuration of a display device according to an embodiment of the present invention.

2 illustrates a test pattern signal according to an exemplary embodiment of the present invention.

3 is a flowchart illustrating a step-by-step control method of a display apparatus according to an exemplary embodiment of the present invention.

4 is a flowchart illustrating a brightness adjustment method of a display apparatus according to an exemplary embodiment of the present invention in more detail.

5 is a flowchart illustrating a contrast adjusting method of a display apparatus according to an exemplary embodiment of the present invention in more detail.

6 is a flow chart for explaining in detail the color adjustment method of the display device according to an embodiment of the present invention.

Claims (9)

A storage unit which stores a reference level value for each area of the test pattern signal; A signal input unit for receiving a test pattern signal from a connected external video device; A level value detector configured to signal-process a test pattern signal input through the signal input unit and detect a level value for each preset area; And, And a controller configured to set an image quality related adjustment value according to a signal characteristic of the connected external video apparatus according to a difference between a level value of each region detected by the level value detector and a reference level value stored in the storage unit. Display device characterized in that. The method of claim 1, It further comprises a signal output unit for outputting the pre-stored reference test pattern signal to the connected external video device, And a test pattern signal input from the connected external video device is a reference test pattern signal output through the signal output unit. The method of claim 1, The display device may include at least one of Y offset, Y gain, Cb offset, Cb gain, Cr offset, and Cr gain. The method of claim 1, And the control unit stores the set quality related adjustment value in the storage unit in response to product information of the connected external video device. Outputting a reference test pattern signal to the connected external video device as a connection of an external video device is detected; Re-input of the output reference test pattern signal from the connected external video apparatus; Acquiring a level value for each preset area based on a reference test pattern signal input from the external image device; And, And setting at least one image quality related adjustment value according to at least one signal characteristic of the connected external video apparatus based on the obtained level value of each region. The method of claim 5, Acquiring a level value for each region of the reference test pattern signal Separating the reference test pattern signal input from the external video device into a Y signal, a Cb signal, and a Cr signal; Obtaining a level value for a first region and a second region from the separated Y signal; Obtaining level values for a second region and a third region from the separated Cb signal; And obtaining a level value for the second area and the fourth area from the separated Cr signal. The method of claim 6, The setting of the at least one image quality related value may include Comparing the obtained level value for each region with a reference level value for each previously stored region; And setting a quality-related value such that the level value of each of the acquired areas and the reference level value of each of the previously stored areas coincide with each other. The method of claim 7, wherein The setting of the image quality related value Setting a Y offset value such that the obtained Y signal level value for the first region coincides with a previously stored reference level value; Setting a Y gain value such that the obtained Y signal level value for the second region coincides with a previously stored reference level value; Setting a Cb offset value such that the obtained Cb signal level value for the second region coincides with a previously stored reference level value; Setting a Cb gain value such that the obtained Cb signal level value for the third region matches a previously stored reference level value; Setting a Cr offset value such that the obtained Cr signal level value for the second region coincides with a previously stored reference level value; And setting a Cr gain value such that the obtained Cr signal level value for the fourth region coincides with a pre-stored reference level value. The method of claim 8, And storing the set Y offset, Y gain, Cb offset, Cb gain, Cr offset, and Cr gain values corresponding to product information of the connected external video device.

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