JP2009044400A - Image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that it is necessary for a user to change setting on the receiver side in order to obtain an optimal angle and an optimal image quality depending on types of external connection devices when a signal transmitted by HDMI standards is received. <P>SOLUTION: An image display device includes: an HDMI connector to which a digital transmission bus based on the HDMI standards is connected; an HDMI signal processing part which performs decoding processing of a video signal from a digital signal received via the HDMI connector, restores a first video signal, and when connected device information is included in the received digital signal, extracts and outputs the connected device information; a control part which automatically sets scanning size to a display according to the connected device information; an image quality processing part which automatically sets image quality setting to the display to the optimal image quality according to the connected device information when a selector selects the first video signal and the connected device information is extracted, wherein the scanning size of a displayed image is automatically set and the optimal image quality setting is automatically performed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image display device capable of selectively displaying a video signal obtained by receiving a broadcast signal and a video signal from a signal input terminal by a digital interface, and in particular, an image scan size and image quality setting. The present invention relates to an image display apparatus that can automatically display the image automatically and optimally.

  As is well known, the DVI (Digital Visual Interface) standard is widely used as a standard for transmitting digital video signals. In recent years, the High Definition Multimedia Interface (HDMI) standard has come to be adopted as a digital signal transmission standard that further improves the DVI standard.

  In the HDMI standard, for example, it is possible to multiplex a digital audio signal during a blanking period of a digital video signal and perform audio transmission. In addition to the R, G, and B formats, the digital signal can have a color difference (Y, Various specifications not included in the DVI standard are included, such as being able to transmit in the Cb, Cr) format and being able to connect with a USB (Universal Serial Bus) -like small HDMI connector. .

  Therefore, recently, some television signal receivers are provided with an HDMI input terminal, and a digital signal compliant with the HDMI standard can be supplied to the input terminal from an external device. Examples of such external devices include a DVD (Digital Versatile Disk) player, a DVD recorder, an STB (Set Top Box, Set top Box), a high-definition movie, a PC (Personal Computer, Personal Computer), and the like. An external device and a television signal receiver are connected via an HDMI connector.

  When a user of a television signal receiver connected to an external device via these HDMI connectors selects a plurality of externally connected devices connected to the television signal receiver, the scan size and image quality are The settings are changed manually. As a result, the television signal receiver appropriately displays image information. For example, the user manually sets the scan size and image quality of the television receiver device by using an interface such as a GUI (graphical user interface).

Patent Document 1 discloses a configuration in which the display mode on the receiving side is automatically set according to display-related information such as aspect information extracted from a digital signal received via an HDMI connector. It is not considered to automatically determine the type of connected device, or to automatically set the scan size and image quality settings.
JP 2006-108750 A

  Most television signal receivers that receive video signals transmitted according to the HDMI standard and display images as described above are connected devices such as DVD players, DVD recorders, and STBs. Therefore, since the main consideration is to display moving images, the image quality setting emphasizes overscan settings, contrast, and sharpness. When displaying text or geometric figures such as PC on the television signal receiver, the display area is missing due to overscan settings, or gradations and thin lines are crushed. The scan size and image quality are not optimal.

  In view of the foregoing, it is an object of the present invention to provide an image display apparatus that can determine an externally connected device and optimally set a scan size and image quality for the externally connected device.

  The present invention is an image display device for solving such problems, and includes an HDMI connector to which a digital transmission bus compliant with the HDMI standard is connected, and a digital signal received via the HDMI connector. An HDMI signal processing unit that decodes the video signal to restore the first video signal, and extracts and outputs the connected device information when the received digital signal includes the broadcast signal; A second video signal including the video signal received and processed, a selector for selecting and outputting any one of the first video signals, and an image based on the video signal selected and output by the selector. A display for displaying, and when the selector selects the first video signal and the connected device information is extracted, the connected device A control unit that automatically sets a scan size for the display in response to the information, and the selector selects the first video signal, and when the connected device information is extracted, And an image quality processing unit that automatically sets an image quality setting for the display to an optimum image quality.

  Further, the present invention is an image display device for solving the above-described problems, in which a video signal is decoded from a digital signal received via a digital signal bus compliant with the HDMI standard, A step of restoring the first video signal and extracting the connected device information when the CEC control line of the received digital signal is included, and a second signal including the video signal obtained by receiving the broadcast signal And a step of selectively outputting any one of the video signals, and a response to the extracted connected device information when the first video signal is selectively output. And automatically setting the scan size on the display, and when the first video signal is selected and output, the display is responsive to the extracted connected device information. Characterized in that it comprises a step of automatically setting the optimum image quality settings.

  According to the present invention, it is possible to automatically set a scan size of a display image and automatically perform optimum image quality setting in response to externally connected device information extracted from a digital signal received via an HDMI connector. A possible image display device can be realized.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

(Embodiment 1)
FIG. 1 shows a block diagram of an image display apparatus according to Embodiment 1 of the present invention. The image display device 11 has a function of receiving a television broadcast signal, a function of receiving an analog video, and a function of receiving a digital video signal compliant with the HDMI standard.

  That is, the television broadcast signal is received by the antenna 12 and supplied to the television signal processing unit 14 via the input terminal 13. The television signal processing unit 14 extracts a signal of a predetermined channel from the input television broadcast signal by the tuner unit 14 a, restores the video signal by the signal processing unit 14 b, and outputs it to the selector 15.

  The analog video signal is received by an AV (Audio Video) input terminal 16, converted into a digital signal by the AD conversion unit 28, and then input to the selector 15.

  Further, the digital video signal supplied from the external connection device A17 via the digital transmission bus 18 compliant with the HDMI standard is received by the HDMI connector 19 and from the external connection device B22 via the digital transmission bus 29 compliant with the HDMI standard. The digital video signal supplied is received by the HDMI connector 30 and supplied to the HDMI signal processing unit 20. As will be described in detail later, the HDMI signal processing unit 20 restores the video signal from the input digital signal conforming to the HDMI standard, and outputs it to the selector 15. Further, the HDMI signal processing unit 20 acquires CEC information from the CEC control lines of the digital transmission bus 18 and the digital transmission bus 29, extracts connected device information from the CEC information, and notifies the control unit 23.

  The selector 15 selectively switches between the video signal output from the television signal processing unit 14, the video signal output from the AV conversion unit 28, and the video signal output from the HDMI signal processing unit 20. The video signal is supplied to the video signal processing circuit 21. The video signal from the video signal processing circuit 21 is supplied to the display 40, and the video is reproduced and displayed.

  Here, in the image display device 11, most of the operations including the various reception operations described above are controlled by the control unit 23. The control unit 23 is composed of a microprocessor incorporating a CPU (Central Processing Unit) or the like, receives operation information from the operation unit 24, or receives operation information sent from the remote controller 25 via the reception unit 26. Receiving and controlling each part so that the operation content is reflected.

  At this time, the control unit 23 uses the memory unit 27. That is, the memory unit 27 stores a read-only memory that mainly stores a control program executed by the CPU of the control unit 23, a read / write memory that provides a work area for the CPU, and various setting information and control information. Non-volatile memory.

  The video signal processing circuit 21 scales the signal selected by the selector 15 in accordance with the number of pixels of the display 40, and performs overscan processing, underscan processing, or just scan processing of the display image. Thereafter, image quality correction such as contrast and enhancer is performed, and video is output to the display 40.

  Next, a schematic configuration of the HDMI signal processing unit 20 will be described. FIG. 2 is a block diagram showing a configuration of the HDMI signal processing unit used in the image display apparatus according to Embodiment 1 of the present invention. As shown in FIG. 2, the HDMI signal processing unit 20 includes an HDMI receiving circuit 201, an EDID memory A202, an EDID memory B203, an HDCP memory 205, a video signal output circuit 204, and a sub control unit 206. The HDMI connector 19 and the HDMI receiving circuit 201 and the HDMI connector 30 and the HDMI receiving circuit 201 are connected by a high-speed digital transmission path for transmitting a video signal and a communication control bus for transmitting control information. ing.

  The HDMI receiving circuit 201 has a function of selecting a digital signal input from the HDMI connector 19 and the HDMI connector 30 via the high-speed digital transmission path and the communication control bus, and the control unit 23 switches the input signal.

  The EDID memory A202 and the EDID memory B203 store control information related to the display 40, for example. EDID is an abbreviation for Extended Display Identification Data, and information on the display side (corresponding signal format, resolution, number of pixels, etc.) from the display side (image display device 11) to the host side (external connection device 17, external connection device 22). ). The HDCP memory 205 stores key data for controlling copy protection of digital input signals input via the HDMI connector A19 and the HDMI connector B30. HDCP is an abbreviation for High Band Digital Content Protection.

  The sub-control unit 206 detects the signal input state from the HDMI connector A19 and the HDMI connector B30. That is, the sub-control unit 206 detects whether or not there is a signal input from the HDMI connector A19 and the HDMI connector B30, extracts connected device information from a CEC (Consumer Electronics Control) control line, or the like, or HDMI connector A19. And input switching of the HDMI connector B30. The sub-control unit 206 communicates with the main control unit 23, controls the selector 15 based on detection of a signal input state and a signal selection instruction from the main control unit 23, and is supplied from the HDMI connector A19 or the HDMI connector B30. Select the input signal.

  The connected device information input from the CEC control line includes a manufacturer ID and a device type ID, and information on the connected device is obtained by extracting the two IDs. As the device type ID, DVD, STB, movie, and the like are determined by the standard, and other items can be operated by making arrangements between manufacturers. The PC of the external connection device B22 and the image display device 11 of the present invention used in this embodiment use a device type ID having a PC ID command.

  Next, as an example, a case where a DVD recorder is connected to the external connection device A17 and a PC is connected to the external connection device B22 will be described with reference to the flowchart of FIG. 3 and the image processing image diagrams of FIGS. FIG. 3 is a flowchart showing processing differences due to differences in externally connected devices in the first embodiment of the present invention. FIG. 4 is an image diagram of angle-of-view processing in which video is processed in Embodiment 1 of the present invention, and FIG. 5 is an image diagram of image quality processing in which video is processed in Embodiment 1 of the present invention.

  When the image display device 11 selects the DVD recorder of the external connection device A17 as the selection of the external connection device, the HDMI signal processing unit 20 extracts the connection device information from the CEC control line, and the external connection device A17 is a DVD. And notifies the control unit 23 of the information (step S310). In response, the control unit 23 determines that the externally connected device A17 is not a PC (NO in step S320), sets the scan size of the video signal processing circuit 21 to be overscanned (step S343), and sets the image quality. The moving image quality processing setting is performed so that the moving image is optimally reproduced (step S344). FIG. 4A shows a display area for a video signal in the case of overscan. In addition, the setting of image quality shows the output drive level displayed on the display 40 with respect to the input signal level by taking contrast as an example in FIG.

  In general, in the case of a video received by a DVD or broadcast, most image display apparatuses are assumed to be a moving image source. It is assumed that the source of video sent by DVD or broadcast is displayed on the receiving device side with overscan, and there is no video up to the end of the display area. There are many cases where garbage etc. is added when processing. For this reason, on the receiving device side such as the image display device 11, an overscan is performed so that the end of the video is outside the display area of the display 40 and is not displayed on the screen.

  As can be seen from FIG. 4A, in the case of the overscan processing, the peripheral portion of the video is not displayed hidden behind the screen.

  In addition, with regard to image quality, for example, instead of linearly reproducing gradations so that the appearance during video playback can be seen clearly, a high brightness part such as white is reproduced by raising the gradations and reproducing it. Emphasis is made so that a low-luminance portion such as black is rendered to the black side by black expansion or the like to produce a contrast feeling. With respect to the boundary portion of a picture or a character, the boundary portion is emphasized, an edge is set up, and a thin line or the like is emphasized thickly so that the image is sharpened. FIG. 5A shows a contrast image as an example. As can be seen from FIG. 5A, the portion where the input signal level is low, that is, the portion close to black is dropped to the black side by dropping the output drive from the level of the input signal. The brightness is increased by increasing the output drive in the area close to. By performing such an operation, the sharpness of the image becomes stronger and the contrast is emphasized.

  However, when the PC signal of the external connection device B22 is input in the moving image display setting, the OS (Operating System) having an operation part such as an operation icon at the edge of the screen or a picture, figure or text for presentation is mainly used in the PC signal. If the same processing as the display setting for a movie such as a DVD is performed, the operating portion of the OS at the edge of the screen is hidden by the overscan processing, and the picture and graphics for the presentation are processed by the image quality processing. This causes problems such as that it looks different from what is intended, or that text characters are crushed and cannot be read. In order to solve this problem, the user has to adjust the image quality by adjusting the scan size of the image display device so that the optimum scan size is obtained every time the external device is switched.

  Therefore, in the present embodiment, the case where the image display device 11 is connected to the external connection device B22 as the input device selection will be described with reference to FIGS.

  Here, when the PC of the external connection device B22 recognizes the device information of the image display device 11 of the present invention by the CEC control line of the digital transmission bus 29, it is the same as the number of pixels of the display 40 of the image display device 11 of the present invention. A signal in the format of the number of pixels can be output. When the number of pixels of the display and the number of pixels of the video signal are combined, the video signal is not scaled, so that deterioration of the image quality due to scaling can be avoided and the image quality can be improved.

  In FIG. 3, when the externally connected device B22 is a PC, the HDMI signal processing unit 20 extracts the connected device information through the CEC control line, and the externally connected device B22 is a manufacturer ID and PC that are processed as a PC signal. And notifies the control unit 23 of the information (step S310). In response, the control unit 23 determines that the externally connected device A17 is a PC (YES in step S320), determines whether the received signal is a PC control target format, and the number of pixels of the received signal is the image display. It is determined whether or not the number of pixels of the display 40 of the device 11 matches (step S330). If they match, it is determined that the format is subject to PC control, and the control unit 23 automatically sets the scan size of the video signal processing circuit 21 to just scan without overscan as shown in FIG. Then, a just scan process (step S341) for displaying all the input images on the display is performed. Then, the image quality processing performs image quality processing for a personal computer that displays the input video without emphasizing processing (step S342). As a result, it is possible to optimally display text and graphics, and to automatically reproduce images according to the creator's intention, such as presentation materials and image data created on a PC.

  FIG. 5B shows a contrast image as an example. As can be seen from the example of FIG. 5B, the output drive level is not linearly corrected with respect to the input signal level, and is displayed linearly, such as presentation materials and image data created on a PC, according to the intention of the creator. Can be played. In this embodiment, only the gradation portion is described as the image quality, but it is also necessary to change the settings for parameters such as color density, hue, and edge enhancement for video such as DVD and PC.

  As described above, according to the embodiment of the present invention, the optimum setting can be realized without the user being particularly conscious by automatically setting the scan size and the image quality according to the video characteristics of the externally connected device. Is possible.

  The image display apparatus according to the present invention automatically sets the scan size of the display image in response to the external connection device information extracted from the digital signal received via the HDMI connector, and automatically sets the optimum image quality setting. Since it is possible to realize an image display device that can perform, an image that can selectively display an image by a video signal obtained by receiving a broadcast signal and an image signal from a signal input terminal by a digital interface The present invention relates to a display device, and is particularly useful as an image display device that can automatically and optimally display an image scan size and image quality setting.

1 is a block diagram of an image display device according to Embodiment 1 of the present invention. The block diagram which shows the structure of the HDMI signal processing part used with the image display apparatus in Embodiment 1 of this invention. The flowchart showing the difference of the process by the difference of the external connection apparatus in Embodiment 1 of this invention Image diagram of angle-of-view processing for processing video in Embodiment 1 of the present invention The image figure of the image quality process which processed the image | video in Embodiment 1 of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Image display apparatus 12 Antenna 13 Input terminal 14 Television signal processing part 14a Tuner part 14b Signal processing part 15 Selector 16 AV input terminal 17 External connection apparatus A
18 Digital transmission bus 19 HDMI connector A
20 HDMI signal processing unit 21 Video signal processing circuit 22 Externally connected device B
23 Control Unit 24 Operation Unit 25 Remote Controller 26 Receiver 27 Memory Unit 28 AD Converter 29 Digital Transmission Bus 30 HDMI Connector B
40 display 201 HDMI receiving circuit 202 EDID memory A
203 EDID memory B
204 Video signal output circuit 205 HDCP memory 206 Sub-control unit

Claims (3)

An HDMI connector to which a digital transmission bus compliant with the HDMI standard is connected, and a video signal is decoded from a digital signal received via the HDMI connector to restore a first video signal, and the received An HDMI signal processing unit that extracts and outputs connected device information transmitted using a CEC control line of a digital signal, a second video signal including a video signal obtained by receiving a broadcast signal, and the first signal A selector for selecting any one of the input video signals; a display for displaying an image based on the video signal selected and output by the selector; and the selector selects the first video signal; A control unit that automatically sets a scan size for the display according to the connected device information when information is extracted; When the selector selects the first video signal and the connected device information is extracted, an image quality processing unit that automatically sets an image quality setting to the display to an optimal image quality according to the connected device information; An image display device comprising: The connected device information notified by the CEC control line included in the received digital signal includes device type information, and the control unit responds to the device type information extracted by the HDMI signal processing unit. The image display device according to claim 1, wherein overscan of an image displayed on the display is set. The connected device information notified by the CEC control line included in the received digital signal includes device type information, and the control unit responds to the device type information extracted by the HDMI signal processing unit. The image display apparatus according to claim 1, wherein an optimum image quality of an image displayed on the display is set.

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