JP2003070018A - Video signal processing circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the image quality of composite video materials by discriminating between an SDTV (standard TV) signal and an HDTV (high-definition TV) signal on a receiver side, converting a component type signal into a composite type signal when the inputted signal is an SDTV signal, and using a high- performance YC separator. SOLUTION: In a television receiver in which a receiver of digital BS (broadcasting satellite) or digital terrestrial broadcasting is connected, the digital broadcast receiver has a composite signal output 102 and a component signal output 103, and also has a switching circuit 110 for switching an output between a first component signal from the output 103 and a second component signal obtained, by applying three-dimensional YC separation and chroma-decoding to the output 102. Further, the receiver has a frequency discrimination circuit 105 for judging the first component signal to be an SDTV signal or an HDTV signal. If the circuit 105 discriminates as the SDTV signal, the circuit 110 selects a second component signal and switches, thereby improving the image quality of the composite video materials.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a television receiver for connecting a digital broadcasting receiver for BS, terrestrial waves, etc. (hereinafter referred to as a digital tuner) or a television receiver having a digital broadcasting receiving circuit incorporated therein, and a digital broadcasting receiver. In particular, the present invention relates to a technique for improving image quality of composite video material.

[0002]

2. Description of the Related Art With respect to the conventional technology of digital broadcasting, FIGS. 8 and 9 show a transmission method and a reception method for video materials (component materials and composite materials) on the broadcasting station side and the television receiver side. In the current digital broadcasting, as shown in FIG. 8, on the broadcasting station side, a composite signal 201 (a format in which the video material is combined with luminance and color) and a component signal (a format in which the video material is separated into luminance and color) 206 Of 2
There are different types of video material. The component signal 206 is
The data is encoded by the MPEG2 encoder 205 via the switching circuit 204, modulated by the mod 210 and transmitted.

On the other hand, the composite signal 201 is Y / C
The signal is converted into a component signal through the separation 202 and the chroma decoder 203, and the MPEG2 is converted through the switching circuit 204.
It is encoded by the encoder 205, modulated by the mod 210, and transmitted.

The transmitted signal is decoded into a component signal 103 by the digital tuner 101 and connected to the input circuit 104 of the television receiver as shown in FIG. Image is processed by processor BEP111 and CRT output 1
The image is displayed at 12.

Further, as a technique close to the above-mentioned conventional technique, Japanese Patent Laid-Open No. 63-84331, "Remote loopback of digital multiplex converter", Japanese Patent Laid-Open No. 3-24036.
No. 9, "Image communication technology", Japanese Patent Laid-Open No. 6-284392, "Video signal transmitting / receiving device", and the like are mentioned.

[0006]

In BS digital broadcasting, a standard television signal (SDT) having 525 scanning lines is used.
V) and a high-definition television signal (HDTV) with 720 or 1125 scanning lines. HD
On TV, all signals are in component format, and SDT
In V, there are two video materials, a component signal and a composite signal.

In the case of SDTV, according to the conventional technique, it is displayed as a component signal on a television receiver regardless of the type of video material (component material or composite material). Video materials handled by the broadcasting station are being replaced with component signals by the start of BS digital broadcasting, but at present, composite signals are often used for convenience.

In the case of a composite video material on the broadcasting station side as well, the YC separation circuit is improved and converted into a component signal before being MPEG encoded and transmitted. However, the component video received through a digital receiver is received. However, due to insufficient performance of the YC separation circuit and the like, there are many cross colors, dot interference, and the like.

According to the present invention, whether the receiver side is SDTV or H
It is to determine whether it is a DTV, convert the component format signal to a composite format signal in the case of SDTV, and use high-performance YC separation to improve the image quality of the composite video material.

[0010]

To solve the above problems, the present invention mainly adopts the following configurations. BS
Alternatively, in a television receiver to which a terrestrial digital broadcast receiver is connected, the digital broadcast receiver has a composite signal output in a format in which the video material is combined with luminance and color and the video material is separated into luminance and color. A component signal output in the form of a first component signal from the component signal output, and a second component signal obtained by subjecting the composite signal output to three-dimensional YC separation and chroma decoding to output the component signal. And a frequency discriminating circuit for discriminating whether the first component signal is a standard television signal or a high-definition television signal, and the frequency discriminating circuit discriminates a standard television signal. The switching circuit selects and switches the second component signal to select a high-definition television. Said first component signal to the switching circuit and tio tone signal and determines to switch selection, the video signal processing circuit for improving the image quality of the composite video material.

Further, in the video signal processing circuit, the digital broadcast receiver has a D terminal control signal output, and in the case of a standard television signal of video material shot by a high-definition camera, the aspect of the D terminal control signal A video signal processing circuit for switching and selecting the first component signal based on information.

The video signal processing circuit further includes a signal presence / absence determining circuit for determining the presence / absence of a video signal in the composite signal output of the digital broadcast receiver. A video signal processing circuit for switching and selecting one component signal and always outputting a video regardless of the type of the digital broadcast receiver.

In the video signal processing circuit, a noise reduction circuit and a coring circuit are provided on the output side of the switching circuit, and the noise reduction circuit and the coring circuit are provided on the basis of the discrimination between the standard television signal and the high-definition television signal. A video signal processing circuit that further improves the image quality of composite video material by changing the setting data of the coring circuit.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION A BS according to an embodiment of the present invention,
1 to 7 for a video signal processing circuit of a television receiver for connecting a digital broadcasting receiver for terrestrial waves (hereinafter referred to as a digital tuner) or a television receiver incorporating a digital broadcasting receiving circuit. However, it will be described below.

First, the background and gist of the present invention will be outlined. In digital BS broadcasting, SDTV (standard television signal: 525 scanning lines) and HDTV (high-definition television signal: 1125 scanning lines or 72)
Two types of broadcast (0) are transmitted. This digital BS
In broadcasting, particularly in the case of SDTV, two types, that is, a component format in which video material is separated into luminance and color and a composite format in which video material is composed of luminance and color, are used differently for each program. Then, the signals of these two formats are unified and broadcast in the component format.

On the other hand, on the receiver side, conventionally, the received signal in the component format is input to the display device and displayed on the screen. In such a conventional technique, when a broadcast signal is broadcast using a composite format signal in which luminance is combined with color, cross color and dot interference are seen on the display device on the receiver side, resulting in a dirty image ( In some cases (due to insufficient performance of the YC separation circuit and the like in the case of unified broadcasting to the component format on the broadcasting station side). Here, in the case of HDTV, the above-mentioned dirty image does not occur because all video materials are in the component format in which luminance and color are separated.

Therefore, in the present invention, basically, the receiver side discriminates between SDTV and HDTV, and in the case of SDTV, the video signal is always received in the component format in which the video signal is separated into luminance and color. The material is converted into a composite format in which the luminance and the color are combined, and then the luminance and the color are separated from the composite signal with good performance so as to be displayed on the display device. An image can be displayed neatly by performing such processing.

Here, even in the case of SDTV, since the image material shot by a high-definition camera has the component format, in this case, the conversion processing to the composite format as the SDTV signal is not performed, and the display device remains in the component format. Will be sent to. The method for determining such a state is based on aspect information (screen aspect ratio information, which is two types of 4: 3 and 16: 9 in the case of SDTV) sent together with video information. : 9, the component format is sent as it is to the display device.

Next, a specific configuration according to the embodiment of the present invention will be illustrated and described. FIG. 1 is a configuration block diagram of a video signal processing circuit according to a first embodiment of the present invention. The video signal processing circuit of this embodiment includes a BS, a terrestrial digital tuner 101, a tuner composite video signal 102, a tuner component video signal 103, a component video signal input circuit 104, a frequency discrimination circuit 105, a microcomputer 106, and a composite video signal input circuit. 107, 3
Dimensional YC separation circuit 108, chroma decorator 109, component A and component B signal switching circuit 11
0, BEP (back end processor) video processing circuit 1
11, a CRT output circuit 112.

Next, the operation of the first embodiment shown in FIG. 1 will be described in detail. A component signal 103 output from the digital tuner 101 passes through an input circuit 104 and a frequency discrimination circuit 105 and a component switching circuit 1
Sent to 10. On the other hand, the composite signal 102 output from the digital tuner 101 is input to the input circuit 107.
Through the three-dimensional YC separation circuit 108 and is demodulated by the chroma decoder 109 into a component signal. This component signal is sent to the component switching circuit 110.
Send to. Here, the composite signal 102 is the component signal sent from the broadcasting station encoded in NTSC by the digital tuner 101,
It is also possible to obtain a composite signal from the component signal 103.

The detailed structure of the frequency discriminating circuit 105 is composed of a sync separation circuit, a horizontal frequency counter, a vertical frequency counter, and a data conversion circuit (not shown), and the component signal 103 from the input circuit 104 is separated into the sync separation circuit. Then, the horizontal sync signal is sent to the horizontal frequency counter to measure the horizontal frequency, the vertical sync signal is sent to the vertical frequency counter to measure the vertical frequency, and the data is sent to the microcomputer 106 after data conversion.

The microcomputer 106 that controls the component signal switching circuit 110 outputs the component signal 103 to the frequency discriminating circuit 105 and the microcomputer 106 by 525.
When it is determined to be the I signal (15 KHZ), that is, the received unified component signal is 5 in the frequency determination circuit.
When it is determined that there are 25 interleaved signals, the type of received broadcast is SDTV instead of HDTV,
In the case of SDTV, regardless of whether the video material is in the composite format or the component format, it is converted into a composite signal and a system on the component B side is formed via a three-dimensional YC separation circuit and a chroma decoder, and this component B side is selected. The switching circuit 110 is controlled as described above.
Incidentally, regardless of the format of the video material on the SDTV, the received unified component signal is not only the output of the composite signal 102 described above but also the component signal 103.
Is output from the digital tuner 101. In the system on the component A side, the received signal is SDT
In the case of V, it is not adopted in the control of the frequency discriminating circuit and the microcomputer.

On the broadcast station side, as shown in the conventional example of FIG. 8, the composite signal and the component signal are switched and encoded with the component signal. The high-definition signal is sent from the D5VTR component signal 206 and encoded and sent. On the other hand, the 525I signal is D3V
It is transmitted from the TR composite signal 201, subjected to YC separation processing 202, converted into a component signal, and then encoded and transmitted. If the performance of the YC processing portion or the like at this time is not sufficient, a component signal with cross color dot interference or the like will be obtained.

When the state of the broadcasting station side as described above is judged, 5
When it is determined to be a 25I signal (15 KHZ), it is determined to be an SDTV that may include a composite material, and the signal obtained by converting the component signal into the composite signal 102 is processed by the three-dimensional YC separation circuit 108, thereby causing cross color dot interference on the broadcasting station side. Etc. are removed to improve the image quality of SDTV composite material, and after the switching circuit 110, BEP
It is displayed on the CRT output 112 via the (video processing circuit) 111. In this embodiment, the component-format video material in SDTV is also converted into a composite signal.
The signal processed by the system on the component B side is adopted.

Next, FIG. 2 is a configuration block diagram of a video signal processing circuit according to a second embodiment of the present invention. The video signal processing circuit of the present embodiment is obtained by adding a D terminal control signal 120 and a D terminal control determination circuit 121 to the circuit configuration of the first embodiment described above (in FIG. 2, the control signal determination circuit 121 is Although it is provided in the microcomputer 106,
The discrimination circuit 121 may be provided outside the microcomputer).

The operation of the second embodiment shown in FIG. 2 will be described below. The operation of the circuit configuration common to the first embodiment is the same as the operation of the first embodiment, and thus is incorporated herein. Explaining the added circuit configuration, the D terminal control signal 120 of the digital tuner 101 will be described.
From the microcomputer 10 having the control signal discrimination circuit 121 built-in
In 6, it is possible to add a determination condition for determining the image material, further improve the determination accuracy of whether the image material is the composite material, and perform the system switching of the component signal switching circuit 110.

The microcomputer 106 receives the D terminal control signal 120 generated by the digital tuner 101, determines the control voltage, and determines the format such as the number of scanning lines, scanning method, and aspect ratio. The D terminal has a squeeze signal and a letter BOX identification signal, but such a signal is sent as a 525I signal, which means that the broadcasting station side is a down-converted signal from the HDTV camera and the original material is a component signal. Can be determined.
In the letter box signal, it can be determined that the recording source material is a component signal in a DVD material or the like.

As described above, even the SDTV has the component format in the case of the video material photographed by the high-definition camera, and therefore the SD as described in the first embodiment.
The processing as the TV signal is not performed and the component format is sent to the display device as it is (the component A side is switched and selected). If the screen aspect ratio is 16: 9 in the aspect information of the D terminal control signal, the component A side is switched and selected. Therefore, the image quality of the composite material can be improved by improving the accuracy of determining whether or not the video material is the composite material. The control signal determination circuit may be provided as a separate circuit outside the microcomputer. Since the letter box signal may be sent as a composite material due to the convenience of the broadcasting station, only the squeeze signal may be determined as a component material.

Next, FIG. 3 is a configuration block diagram of a video signal processing circuit according to a third embodiment of the present invention. The video signal processing circuit of the present embodiment has the input signal discrimination circuit 122 added to the circuit configuration of the second embodiment described above.

The operation of the third embodiment shown in FIG. 3 will be described below. The operation of the circuit configuration common to the second embodiment is the same as the operation of the second embodiment, and thus is incorporated herein. Explaining the added circuit configuration, the composite signal is extracted from the input circuit 107 in the preceding stage of the three-dimensional YC separation circuit 108, and the input signal determination circuit 122 determines the presence or absence of a video signal based on the extracted signal. When the composite signal 102 of 101 is not output depending on the type of the digital tuner 101, the switching circuit 11 is set by the microcomputer 106.
By switching 0 to the component A side, it is possible to output an image and to respond without being affected by the type of digital tuner (image output is possible).

Here, the input signal discrimination circuit 122 is composed of a sync separation circuit and a low-pass filter (LPF) (not shown), and synchronously separates the composite signal and DC-converts it with the LPF to create a control voltage. The H level is sent to the microcomputer 106 when the sync signal is present, and the L level is sent to the microcomputer 106 when the sync signal is not present.

In the circuit configuration of FIG. 3 showing the third embodiment, the input signal discriminating circuit is added to the second embodiment, but not limited to this, the input signal discriminating circuit is added to the first embodiment. You may add.

Next, FIG. 4 is a configuration block diagram of a video signal processing circuit according to a fourth embodiment of the present invention. The video signal processing circuit according to the present embodiment has a digital video processing circuit (three-dimensional YNR (Y noise reduction), three-dimensional CNR (C noise reduction), and two-dimensional YNR coring in addition to the circuit configuration of the third embodiment described above. Circuit) 123 and / or a BEP image quality adjusting function.

The operation of the fourth embodiment shown in FIG. 4 will be described below. The operation of the circuit configuration common to the third embodiment is the same as the operation of the third embodiment, and thus the operation is incorporated. Explaining the added circuit configuration, when the video material is determined to be a composite material,
The digital video processing circuit (three-dimensional Y) added in this embodiment
NR, 3D CNR, 2D YNR coring circuit) 1
By changing the setting of the data of No. 23 and controlling the image quality adjustment of the BEP 111, the image quality of the composite material can be further improved.

Next, FIG. 5 is a configuration block diagram of a video signal processing circuit according to a fifth embodiment of the present invention. The video signal processing circuit of this embodiment includes a material discrimination ID signal 130 and a material discrimination ID signal discrimination circuit 131 instead of the D terminal control signal 120 and the control signal discrimination circuit 121 in the circuit configuration of the fourth embodiment described above. It is provided. Further, corresponding to the fifth embodiment shown in FIG. 5, the material discrimination ID encoding circuit 207 is provided on the broadcast station side as shown in FIG.
Then, as shown in FIG.
And a D decode output circuit (address decoder) 217.

The operation of the fifth embodiment shown in FIG. 5 will be described below. The operation of the circuit configuration common to the fourth embodiment is the same as the operation of the fourth embodiment, and thus the description thereof will be incorporated. The added circuit configuration will be described below. In the above-described first and second embodiments of the present invention, in determining whether the image material is a composite signal or a component signal, it is determined that the image material is a composite signal based on information based on the input signal. Fifth
In this embodiment, in order to fundamentally deal with whether it is a composite signal or a component signal, the material discrimination ID encoding circuit 207 is provided on the broadcast station side shown in FIG.
That is, the broadcasting station side of FIG.
As one of the EG information, an ID is sent as additional data to the video data by the encoder 205 according to the video material.

On the digital tuner side shown in FIG. 7, the transport stream data is recombined into various data by the TS decoder 212, the MPEG data is decoded by the MPEG2 decoder 213, and the format of the video signal (D terminal control signal) and the broadcast. Material identification ID signal 2 on the station side
07 is controlled by the address decoder 217 according to decoding and video data, and a control voltage is output to the D terminal control output 120 according to the currently standardized format.
Material identification ID sent to the material identification ID output 130
The signal is decoded and the control voltage is output.

Then, the microcomputer 106 determines the L / H level of the material identification ID signal 130 from the digital tuner to determine whether it is a composite material or a component material. For example, when composite material, output L level,
Switching circuit 1 outputs H level for component material
10, digital video processing circuit 122, and BEP.

By adding a circuit configuration for judging by the material discrimination ID signal discrimination circuit 131 and the microcomputer 106 based on the material discrimination signal 130 shown in FIG. 5 (in FIG. 5, the material discrimination ID signal discrimination circuit 131 is in the microcomputer 106). Although the determination circuit 131 may be provided outside the microcomputer), the switching circuit 110 selects the component A side to process the digital image even for the composite material image transmitted by the high-definition signal. Circuit (3D YN
R, 3D CNR, 2D YNR coring circuit) 12
2. By controlling the BEP 111, noise can be reduced and the image quality can be improved by appropriately controlling the image quality.

As described above, by adopting the circuit configurations of the various embodiments of the present invention, the image quality of the composite material in digital broadcasting can be improved. Examples of application include SD broadcasting with composite materials of current BS digital broadcasting and HD broadcasting with composite materials.

In this embodiment, the digital tuner (digital broadcast receiver) has been described as an external type of the television receiver, but a television receiver having a built-in digital broadcast receiving circuit naturally has the same configuration. , The effect is obtained.

As a modified example of the present embodiment, the same effect can be obtained by providing a circuit configuration as shown in FIGS. 1 to 5 in the digital tuner and outputting as a switched component signal. Can be played.

[0043]

According to the present invention, the following effects can be obtained. That is, the composite material is component-converted on the broadcast station side, treated like a component signal of a video image taken by a high-definition camera or the like, and transmitted. According to the present invention, the frequency of the transmitted component signal is discriminated, and whether the SDTV including the composite material or the HDTV is discriminated based on the frequency discrimination result. By switching from the signal to the signal side that performs processing through 3D YC separation, cross color dot interference,
It is possible to obtain a component signal with improved S / N and the like, and it is possible to improve the image quality of the composite material.

Further, by adding the D terminal control signal to the discriminating means, the discriminating accuracy of the composite material can be improved, and the image quality of the composite material can be improved by operating it more reliably.

Further, by adding a control signal for detecting the presence or absence of an input signal to the composite input circuit to the discriminating means, if the composite signal output is not output when the component output is selected depending on the type of the digital tuner, it is necessary to set it on the component side. By outputting the image, it is possible to avoid the state where the image is not output.

Further, by adding a three-dimensional YNR circuit, a three-dimensional CNR circuit, a two-dimensional NR coring circuit, and an image quality adjusting circuit, an SD including a composite material can be obtained.
The image quality of the composite material can be improved by setting the data of these circuits according to the TV determination.

Also, the material identification ID of the video is sent from the broadcasting station side, and the composite material identification means I
By adding a D discriminating circuit, the discriminating material of the composite material is surely operated, and even in the case of the composite material with the high-definition signal, the circuit of each block is appropriately controlled to detect the high-definition signal and the SD signal. It is possible to improve the image quality of composite materials.

[Brief description of drawings]

FIG. 1 is a configuration block diagram of a video signal processing circuit according to a first embodiment of the present invention.

FIG. 2 is a configuration block diagram of a video signal processing circuit according to a second embodiment of the present invention.

FIG. 3 is a configuration block diagram of a video signal processing circuit according to a third embodiment of the present invention.

FIG. 4 is a configuration block diagram of a video signal processing circuit according to a fourth embodiment of the present invention.

FIG. 5 is a configuration block diagram of a video signal processing circuit according to a fifth embodiment of the present invention.

FIG. 6 is a diagram illustrating a circuit configuration example on the broadcast station side corresponding to the fifth embodiment.

FIG. 7 is a diagram showing a circuit configuration example on a digital tuner side corresponding to a fifth embodiment.

FIG. 8 is a configuration block diagram of a video signal processing circuit on the broadcast station side in the related art.

FIG. 9 is a block diagram showing the configuration of a video signal processing circuit on the digital tuner side in the related art.

[Explanation of symbols]

101 Digital Tuner 102 Composite signal 103 Component signal 104,107 input circuit 105 Frequency discrimination circuit 106 Microcomputer 108 three-dimensional YC separation circuit 109 Chroma decoder 110 signal switching circuit 111 BEP (back-end processor) 112 CRT output circuit 120 D terminal control signal 121 Control signal discrimination circuit 122 Input signal discrimination circuit 123 Digital video processing circuit 130 Material identification ID signal 131 Material discrimination ID signal discrimination circuit 207 Material identification ID encoding circuit

Claims (6)

[Claims] 1. A television receiver to which a BS or terrestrial digital broadcasting receiver is connected, wherein the digital broadcasting receiver outputs a composite signal output in a format in which video material is combined with brightness and color, and a video material with brightness. And a second component obtained by subjecting the first component signal from the component signal output and the composite signal output to three-dimensional YC separation and chroma decoding. A switching circuit for switching and outputting a signal, and a frequency discriminating circuit for discriminating whether the first component signal is a standard television signal or a high-definition television signal. If it is determined that the signal is a television signal, the switching circuit switches and selects the second component signal. HDTV said switching circuit and television signals and determines by switching selecting the first component signal, a video signal processing circuit, characterized in that to improve the quality of the composite video material. 2. The video signal processing circuit according to claim 1, wherein the digital broadcast receiver has a D terminal control signal output, and in the case of a standard television signal of video material shot by a high-definition camera, the D signal is output. A video signal processing circuit, wherein the first component signal is switched and selected based on aspect information of a terminal control signal. 3. The video signal processing circuit according to claim 1, further comprising a signal presence / absence determining circuit for determining the presence / absence of a video signal in a composite signal output of the digital broadcast receiver, the signal presence / absence determining circuit If there is no signal, the first
A video signal processing circuit, wherein the component signal is switched and selected so that video is always output regardless of the type of the digital broadcast receiver. 4. The video signal processing circuit according to claim 3, wherein a noise reduction circuit and a coring circuit are provided on the output side of the switching circuit, and the noise reduction circuit and the coring circuit are provided to determine whether the signal is a standard television signal or a high-definition television signal. A video signal processing circuit, which further improves the image quality of a composite video material by changing the setting data of the noise reduction circuit and the coring circuit. 5. The video signal processing circuit according to claim 1, 3 or 4, wherein the digital broadcast receiver directly determines whether the video material used on the broadcast station side is a component signal or a composite signal. A video material discrimination ID signal output for discriminating, and when the video material discrimination ID signal is a component signal, the switching circuit is switched and selected to the first component signal, and when it is a composite signal, the switching circuit To the second component signal and / or change setting data of the noise reduction circuit and the coring circuit. 6. The video signal processing circuit according to claim 1, wherein the television has a digital broadcast receiving circuit built-in instead of the television receiver to which the digital broadcast receiver is connected. A video signal processing circuit as a John receiver and a digital broadcast receiving circuit in place of the digital broadcast receiver.