JP2000244892A - Color video transmission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the circuit of an image pickup and to make the device small-sized by providing a modulating circuit which makes amplitude modulation on the composite signal from a synchronous superposing circuit and outputs it by using as a carrier the dot clock multiplied signal generated by a multiplier by using the dot clock from a timing generator. SOLUTION: When video is picked up by a CCD camera 1 provided at an image pickup part RQ1, a video signal S1 is outputted from the CCD camera 1 to the synchronous superposing circuit 2 in the timing prescribed by the timing generator 4 together with a horizontal synchronizing signal SY1 and a vertical synchronizing signal SY2. The synchronous superposing circuit 2 puts those signals together in one composite signal S2 and sends it out to a modulating circuit 3. The modulating circuit 3 amplitude modulates the composite signal S2 by using as a carrier the dot clock multiplied signal S4 generated by multiplying the dot clock S3 outputted from the timing generator 4 by the multiplier and sends the resulting signal to a demodulating circuit 11 of a video display part SQ1 through a transmission line L1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color video transmission device, and more particularly to a color video transmission device for transmitting a video signal using a charge-coupled device camera and displaying the video signal on a liquid crystal display device at a remote place.

[0002]

2. Description of the Related Art Conventionally, there has been an apparatus as shown in FIG. 2 as this type of color image transmission apparatus. In FIG.
The imaging unit RQ50 includes a video signal S50 and a horizontal synchronization signal SY50.
, A charge coupled device camera (CCD camera) 51 that outputs a vertical synchronization signal SY51, a process amplifier 52 that outputs a color difference signal S51 and a luminance signal S52, an NTSC encoder 56 that outputs a composite signal S53, and a modulation that outputs an amplitude modulation wave. The circuit 53 includes a circuit 53, a timing generator 54 that outputs timings and clocks necessary for the CCD camera 51, and an oscillation circuit 55 that oscillates and outputs the original clock.

An image display section SQ60 is provided with a composite signal S6.
1 and a demodulation circuit 61 that outputs 1
It is output from a TSC-compatible liquid crystal display (LCD) or a television. The output of the oscillation circuit 55 is connected to the input of the CCD camera 51 via the timing generator 54, and the output of the CCD camera 51 is connected to the modulation circuit 53 via the process amplifier 52 and the NTSC encoder 56. Another output of the oscillation circuit 55 is connected to the modulation circuit 53. An output of the modulation circuit 53 is connected to a demodulation circuit 61 via a transmission line L50. The output of the demodulation circuit 61 is NTSC
Connected to a compatible LCD or TV.

In such a color video transmission device,
When an image is captured by the CCD camera 51 provided in the imaging unit RQ50, the image signal S50, the horizontal synchronization signal SY50, and the vertical synchronization signal SY5 are sent from the CCD camera 51 to the process amplifier 52.
1 is output. The process amplifier 52 performs a process for converting these signals into a video signal such as a color difference signal and a luminance signal of an internal sample and hold circuit and a matrix circuit. The color difference signal S51 output from the process amplifier 52
The luminance signal S52 is converted into a composite signal S53 in the NTSC format by signal processing by the NTSC encoder 56. The amplitude of the composite signal S53 is modulated by the modulation circuit 53 using the oscillation circuit 55, and the transmission signal L5
The signal is transmitted to the demodulation circuit 61 via 0. The demodulation circuit 61 demodulates the signal to generate a composite signal S61, and the composite signal S61 is connected to an NTSC composite input of an NTSC-compatible LCD or a video input of a television to output an image.

[0005]

Since the conventional color video transmission apparatus is configured as described above, the video signal output from the CCD camera is converted into the NTSC format to achieve compatibility and established technology. Although there is a merit in terms of this point, it is necessary to convert the signal into the signal of the NTSC system, and there is a problem that the circuit in the imaging unit becomes large.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and a circuit from an image pickup section is reduced by directly modulating a signal from a CCD camera and outputting the signal. It is an object of the present invention to provide a color video transmission device that is smaller than a conventional one in a camera device that requires miniaturization.

[0007]

In order to achieve this object, a color video transmission apparatus according to the present invention comprises an imaging section and a video display section connected via a transmission path. The imaging unit outputs a video signal obtained by capturing an image together with a horizontal synchronization signal and a vertical synchronization signal, and outputs a composite signal by superimposing the horizontal synchronization signal and the vertical synchronization signal on the video signal. A synchronous superimposing circuit, and a modulation circuit for amplitude-modulating and outputting a composite signal from the synchronous superimposing circuit as a carrier using a dot clock multiplied signal generated by the multiplier using a dot clock from a timing generator.

The video display unit includes a demodulation circuit for demodulating a modulated video signal output from the imaging unit to generate a composite signal and a clock, and a synchronization separation circuit for separating a horizontal synchronization signal and a vertical synchronization signal from the composite signal. An analog-to-digital converter that converts the demodulated composite signal to a horizontal synchronization signal using a sampling clock by a clock and digital video data using a vertical synchronization signal, and accumulates the video data for one line memory as an addressed storage signal, Determine the calling order based on the line memory recalled as the calling signal and the clock, horizontal synchronizing signal, and vertical synchronizing signal, recall the line memory as the recalling signal, and then recall the R, G, and B signals. A field that is generated from a signal and output together with the clock, horizontal sync signal, and vertical sync signal. It has a programmable gate array, and a liquid crystal display unit for projecting a color image by the RGB signal.

In this color video transmission apparatus, the configuration of the signal to be transmitted is configured as described above, so that the circuit in the imaging section is reduced and the video signal output from the CCD camera is hardly modified. Since transmission is possible, straightforward color information on a pixel-by-pixel basis can be reproduced on the LCD, so that a video with higher resolution than an NTSC signal can be provided.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a color video transmission apparatus according to the present invention will be described below in detail with reference to the drawings. In FIG. 1, a color video transmission device is an imaging unit.
RQ1 and the video display unit SQ1 are connected via a transmission line L1.

The imaging unit RQ1 is a charge-coupled device camera (CCD camera) 1 that outputs a video signal S1 obtained by capturing an image together with a horizontal synchronization signal SY1 and a vertical synchronization signal SY2, a horizontal synchronization signal SY1, and a vertical synchronization signal SY1. Synchronous superimposing circuit 2 for superimposing signal SY2 on video signal S1 and outputting composite signal S2, composite signal S from synchronous superimposing circuit 2
2 is the dot clock S from the timing generator 4
3, a modulation circuit 3 for amplitude-modulating the dot clock multiplied signal S4 generated by the frequency multiplier 6 as a carrier and outputting an amplitude-modulated wave.

The image pickup unit RQ1 includes an oscillation circuit 5 that oscillates and outputs a clock that is a source of the timing generator 4.
have. The output side of the oscillation circuit 5 is connected to the input of the CCD camera 1 via the timing generator 4, and the output side of the CCD camera 1 is connected to the modulation circuit 3 via the synchronous superimposing circuit 2. Another output side of the timing generator 4 is connected to the modulation circuit 3 via the multiplier 6.

The video display unit SQ1 demodulates the modulated video signal output from the imaging unit RQ1 and outputs a composite signal S1.
1 and a clock S12, a synchronizing separation circuit 12 for separating the horizontal synchronizing signal SY11 and the vertical synchronizing signal SY12 from the composite signal S11, and a horizontal synchronizing signal using the demodulated composite signal S11 as a clock S12 as a sampling clock. SY11, vertical synchronization signal SY1
An analog-to-digital converter (ADC) 13 that converts digital video data S13 into digital video data S13, and video data S13.
Is stored for one line memory as a storage signal S20 addressed, and a line memory 15 recalled as a recall signal S21, a clock S12, a horizontal synchronization signal SY11,
After the calling sequence is determined by the vertical synchronizing signal SY12 and recalled from the line memory 15 as the recall signal S21, the R signal S17, the G signal S18, and the B signal S19 are generated from the recall signal S21, and the clock S14 and the horizontal synchronization are generated. A field programmable gate array (FPGA) 14 that outputs the signal SY15 and the vertical synchronizing signal SY16, and RGB signals S17 and S1.
8. A liquid crystal display (LC
D) 16.

The output side of the modulation circuit 3 of the imaging section RQ1 is connected to the demodulation circuit 11 of the video display section SQ1 via the transmission line L1. The output side of the demodulation circuit 11 is an ADC 13 and an FPGA 14,
There are three systems connected to the FPGA 14 via the sync separation circuit 12 and to the FPGA 14 via the ADC 13. The output side of the FPGA 14 is connected to the LCD 16, and the input / output is connected to the line memory 15. The output side of the sync separation circuit 12
It is also connected to ADC13.

In the color video transmission apparatus thus configured, when an image is captured by the CCD camera 1 provided in the imaging section RQ1, the CCD camera 1 transmits the video signal to the synchronous superimposing circuit at the timing specified by the timing generator 4. The video signal S1 is the horizontal synchronization signal SY1 and the vertical synchronization signal SY
2 is output. The synchronous superimposing circuit 2 converts these signals into one and converts them into a composite signal S2, which is sent to the modulation circuit 3, where the composite signal S2 is converted to a dot clock output from the timing generator 4.
The dot clock multiplied signal S4 obtained by multiplying S3 by the multiplier 6 is amplitude-modulated using a carrier as a carrier wave, and transmitted through the transmission line L1 to the demodulation circuit 11 of the video display unit SQ1. Here, the dot clock multiplied signal S4 is a positive integer multiple including 1 of the dot clock S3.

The amplitude-modulated composite signal S2 is demodulated in the demodulation circuit 11 to generate a clock S12 having the same frequency as the dot clock by dividing the frequency of the composite signal S11 and the carrier wave. Sync signal SY11, vertical sync signal
SY12 is separated and generated. ADC1 composite signal S11
In step 3, the clock S12 is used as a sampling clock, and is converted into a parallel digital signal S13 using the horizontal synchronizing signal SY11 and the vertical synchronizing signal SY12.
Enter 4 In the FPGA 14, once the line memory 1
5 as the stored signal S20 addressed to the digital signal S
13 from the line memory 15 in the FPGA 14, the clock S12, the horizontal synchronizing signal SY11 and the vertical synchronizing signal SY1.
2 is used to determine the calling sequence, and is recalled from the line memory 15 as the recall signal S21, and then the R signal S17 and the G signal
The S18 and the B signal S19 are generated from the recall signal S21, and the R signal S17, the G signal S18, the B signal S19 and the clock S12, the horizontal synchronizing signal SY11 and the vertical synchronizing signal SY12 are clocked to the LCD 16 respectively so as to be adapted to the LCD 16. S14, horizontal synchronizing signal SY15 and vertical synchronizing signal SY16
At D16, a color image is projected by the RGB signals S17, S18, S19.

As described above, the video signal output from the CCD camera is converted into a composite signal on which a synchronizing signal is superimposed, and amplitude modulation is performed using a dot clock as a carrier wave, so that the circuit in the imaging section can be reduced.

[0018]

As is apparent from the above description, according to the color video transmission apparatus of the present invention, the configuration of the signal to be transmitted is configured as described above, so that not only the circuit in the imaging section is reduced, but also the CCD camera is used. Since the output video signal can be transmitted with little modification, it is possible to reproduce straightforward color information on a pixel-by-pixel basis on the LCD.
An image with higher resolution than a signal can be provided.

[Brief description of the drawings]

FIG. 1 is an overall block diagram showing an embodiment of a color video transmission device according to the present invention.

FIG. 2 is an overall block diagram showing a conventional color video transmission device.

[Description of Signs] RQ1 ... Imaging unit SQ1 ... Video display unit L1 ... Transmission path 1 ... Charge-coupled device camera (CCD camera) 2 ... Synchronous superimposition circuit 3 ... Modulation circuit 4 Timing generator 6 Multiplier 11 Demodulation circuit 12 Synchronization separation circuit 13 Analog-to-digital converter (ADC) 14 Field programmable gate array (FPG)
A) 15: Line memory 16: Liquid crystal display (LCD) S1: Video signal SY1: Horizontal synchronization signal SY2: Vertical synchronization signal S3: Dot clock S4: Dot clock Multiplied signal S11: Composite signal S12: Clock SY11: Horizontal synchronization signal SY12: Vertical synchronization signal S13: Video data S20: Storage signal S21: Recall signal S17: R signal S18: G signal S19: B signal S14: Clock SY15: Horizontal synchronization signal SY16: Vertical synchronization signal

Claims (1)

[Claims] 1. A color video transmission device in which an imaging unit (RQ1) and an image display unit (SQ1) are connected via a transmission line (L1), wherein the imaging unit is obtained by imaging an image. Video signal (S
A charge-coupled device camera (1) that outputs 1) together with a horizontal synchronization signal (SY1) and a vertical synchronization signal (SY2), and outputs a composite signal by superimposing the horizontal synchronization signal and the vertical synchronization signal on the video signal. A synchronous superimposing circuit (2), which converts a composite signal from the synchronous superimposing circuit into a carrier wave using a dot clock multiplied signal (S4) generated by a multiplier (6) using a dot clock (S3) from a timing generator (4). The video display unit demodulates the modulated video signal output from the imaging unit to generate a composite signal (S11) and a clock (S12). A circuit (11) and a synchronization separation circuit (12) for separating a horizontal synchronization signal (SY11) and a vertical synchronization signal (SY12) from the composite signal.
And an analog-to-digital converter (13) for converting the demodulated composite signal into digital video data (S13) using the horizontal synchronizing signal and the vertical synchronizing signal using a sampling clock based on the clock, and storing the video data addressed. The signal (S20) is stored for one line memory, and the line memory (15) recalled as the recall signal (S21) and the clock, the horizontal synchronizing signal, and the vertical synchronizing signal determine a calling order, and After recalling from the line memory as the recall signal, an R signal (S17), a G signal (S18), and a B signal (S19)
Is generated from the recall signal, and is output together with a clock (S14), a horizontal synchronizing signal (SY15), and a vertical synchronizing signal (SY16).
4) and a liquid crystal display unit (16) for displaying a color image by the RGB signal.