JPH02100799A - Image pickup device - Google Patents

Abstract

PURPOSE:To decrease the number of signal lines by using an idle signal band among the standard video signal lines to transmit the specific information like the alarm information, etc., after multiplexing these information. CONSTITUTION:A standard video signal has a sound band which is higher than a frequency fVmax and has a narrow center frequency fs. Then a microphone is attached to a camera 1 for transmission of the sound information around the camera 1. In such a case, the sound information is transmitted along a sound band. The frequency band of the relevant sound information becomes idle in the case the sound information is not transmitted like an ordinary monitor device. The coincidence is secured between the frequency of the idle sound band and the oscillation frequency (fs) of an oscillator 3. Then the frequency of the idle sound band is mixed with the video signal via a mixing circuit 4, and the presence or absence of the sound signal of the sound band is checked at the side of a center equipment (reception side). Thus it is possible to easily confirm the presence or absence of an alarm signal and a new writing is not required for the alarm information.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a 1Y imaging device that outputs a standard video signal, and mainly relates to an imaging device used for monitoring purposes such as security systems for crime prevention.

[Prior Art] In recent years, as the performance of solid-state imaging devices such as C:CD (charge-coupled device) image sensors has improved, development of imaging devices using these solid-state imaging devices as surveillance cameras has been actively conducted. ing. On the other hand, when monitoring objects in a remote location with a surveillance camera, it is better to be able to monitor not only the image but also the status of alarms such as fire alarms and the measurement output of various detectors. Favorable for work efficiency.

[Problems to be Solved by the Invention] However, with this conventional imaging device, if you want to monitor the status of the alarm, you need to connect the signal cable for the alarm separately from the signal cable for the surveillance camera. The drawback was that it required installing multiple signal cables, resulting in high costs. In particular, if the distance from the monitoring position to the location (center) where the observer is located is long, the cost required to install a new signal cable becomes enormous.

The purpose of the present invention is to eliminate the above-mentioned drawbacks17, provide a new transmission path, and improve the image quality of alarm signals, etc.1. ．． J provides an imaging device capable of transmitting both signals at the same time.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides an image processing apparatus that outputs a standard video signal having an audio band and a color signal band. The present invention is characterized by comprising a signal transmission means for multiplexing and transmitting specific information other than image information and audio information using a signal band that is not used for transmitting information and audio information.

[Function] With the above configuration, the present invention can multiplex specific information such as alarm information using a vacant signal band in a standard video signal.
Since the signal is transmitted over multiple channels, the number of signal lines can be reduced, and the cost required for wiring can be significantly reduced.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a circuit configuration of a first embodiment of the present invention.

In FIG. 1, numeral 1 is an imaging camera, and the object to be monitored (
The image of the subject) is converted into a standard video signal such as the NTSC system and output. 2 is an alarm such as a fire alarm, and to simplify the explanation here, when there is no alarm, the low level,
At the time of alarm, a high level (ri "r-" is output. 3 is an oscillator that outputs a signal in the audio band in response to No. 43 of the alarm 2. When the input terminal 3a is at a low level, It is assumed that no oscillation is output, and when the input terminal 3a is at a high level, a signal of a predetermined amplitude is output. 4 is a mixing circuit (mixer) that mixes the output signal from the camera 1 and the output signal from the oscillator 3. ), and the standard video signal multiplexed by the mixing circuit 4 is conveyed to a distant place through the transmission line 5.

FIG. 2 shows the spectrum of the output signal in the embodiment of FIG. The video signal output from camera 1 is A in Figure 2.
The video band of the standard video signal (fvM+n to fv
yMx).

Sign! In the case of the 11 video signal, as shown in B in Figure 2, it has a narrow audio band with a higher center frequency fs than fv□, and a microphone is attached to camera 1 to collect audio information around the camera. If the system also transmits audio information, this audio information is transmitted in the audio band, but if audio information is not transmitted as in a normal monitoring device, this audio frequency band becomes vacant.

In this embodiment, the frequency of the audio band in the empty state () is matched with the oscillation frequency (fs) of the oscillator 3, and the mixing circuit 4 mixes the signal with the video signal, so that the signal is transmitted to the transmission path 5. The spectrum of the signal is as shown in FIG. Therefore, by detecting the presence or absence of a sound signal in the audio band on the center device side (receiving side), it is possible to easily confirm whether or not an alarm signal is generated, and the presence or absence of an alarm signal can be easily confirmed by using a buzzer, lamp, etc. can be operated. In this way, in this embodiment, the alarm information from the alarm device is multiplexed with the video signal of the camera and transmitted.
No new wiring for alarm information is required. Further, since these alarm information contain less information than the camera video signal, multiplexing is relatively easy.

FIG. 3 shows a signal spectrum when the oscillation frequency of the oscillator 3 mentioned above is fA and a general commercially available video/audio mixing circuit is used as the mixing circuit 4. In this example, transmission line 5
The signals in the bands shown in A and B in FIG. 3 are output.

That is, the mixing circuit 4 modulates the signal of the frequency fA of the alarm information to the frequency fs and transmits the signal.

FIG. 4 shows a circuit configuration of a second embodiment of the present invention. Fourth
In the figure, IO is a monochrome imaging camera (monochrome camera)
, 20 is an alarm device that generates a high-level output signal at the time of an alarm; 30 is an oscillator that outputs a signal of the oscillation frequency fsc of the color subcarrier when the output level of the alarm device 20 is high level;
40 is a mixing circuit that mixes the output signal of the monochrome camera IO and the output signal of the oscillator 30 and outputs the mixed signal from the output terminal 40C to the transmission line 50.

FIG. 5 shows the spectrum of the output signal in the embodiment of FIG. In a standard video signal, the frequency distribution of the luminance signal and color signal is as shown in A and D in Figure 5.
The chrominance signal is a narrow band signal compared to the luminance signal,
It is modulated and transmitted using a carrier wave (color subcarrier) of frequency fsc.

On the other hand, as a practical surveillance camera, a monochrome camera is generally used because a color camera requires an expensive image sensor and a complicated signal processing circuit. In the case of a monochrome camera IO, only the signal A exists in FIG. 5, and the band of the color subcarrier D is vacant.

In this embodiment, when a monochrome camera IO is used as the camera, alarm information is transmitted to this vacant color subcarrier band. Therefore, in this embodiment, if the center device monitors the video using a color TV receiver, it will be in a non-alarm state when it is a black and white image with no color, and it will be in a non-alarm state when the screen has a predetermined color. can be immediately determined to be in an alarm state.

FIG. 6 shows a circuit configuration of a third embodiment of the present invention. 6th
In the figure, 100 is an imaging camera, 200 is a microphone, 300 is an alarm, and 400 is an alarm 30.
An oscillator 500 outputs a signal of an oscillation frequency f2 in the audio band according to the output level of the camera 100.
, a mixing circuit that mixes the output signals of the microphone 200 and the oscillator 400; 600 is a transmission line that transmits the output signal of the mixing circuit 500;

FIG. 7 shows the spectrum of the output signal in the embodiment of FIG. In the frequency allocation of standard video signals, as shown in Fig. 7, video signal A and stereo audio 2 channels B1
．． B2 exists. If you want to enjoy high quality sound,
The entire Bl and 82 bands will be used, but in cases such as monitoring equipment, where information about what is currently happening and what state it is in is sufficient, One channel's worth of information is sufficient as audio information, and the other channel can carry alarm information.

Therefore, in this embodiment, the first channel of B1 is applied to the microphone 200, and the second channel of B2 is applied to the alarm information of the oscillator 400.
These B1 and B2 channels and the video signal A from the camera 100 are mixed by a mixing circuit 500 and transmitted through a transmission line 600, so that they can be monitored by a TV receiver with stereo audio on the center equipment side. If you did,
All information including alarm information can be monitored.

In addition to outputting the alarm information transmitted through the above-mentioned transmission path from the monitor screen or monitor speaker, the alarm information can be frequency-separated and extracted using a filter circuit, and output to other sound generators, display devices, etc. Of course, it is also possible to do so.

In addition, although the above-mentioned embodiment shows an example in which a single alarm device is used, the present invention is not limited to this, and it is also possible to connect multiple alarm devices and transmit using a time division method, a coding method, etc. can.

[Effects of the Invention] As explained above, according to the present invention, specific information such as alarm information is multiplexed and transmitted using an empty signal band in a standard video signal. This has the effect of significantly reducing the cost required for wiring.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the circuit configuration of the first embodiment of the present invention, Fig. 2 is a spectral diagram showing the spectral distribution of the output signal of the embodiment of Fig. 1, and Fig. 3 is a modification thereof. 4 is a plotter diagram showing the circuit configuration of the second embodiment of the present invention, FIG. 5 is a spectral diagram showing the spectral distribution of the output signal of the embodiment of FIG. 4, and FIG. 6 is a spectrum diagram showing the spectral distribution of the output signal of the embodiment of FIG. FIG. 7 is a block diagram showing the circuit configuration of the third embodiment of the present invention. FIG. 7 is a spectral diagram showing the spectral distribution of the output signal of the embodiment of FIG. 1.100...camera, 2.20,300...alarm device, 3.30,400...1 alarm, 4.40,500...mixing circuit, 5.50,600...・Transmission line, 20...monochrome camera. Figure 7 Figure 7

Claims (1)

[Scope of Claims] 1) In an imaging device that outputs a standard video signal having an audio band and a color signal band, the audio band and the color signal band are used for transmitting image information and audio information. 1. An imaging apparatus comprising a signal transmission means for multiplexing and transmitting specific information other than the image information and the audio information using a signal band that is not available.