KR100233110B1 - Adaptive type camera recorder - Google Patents

Abstract

1. TECHNICAL FIELD OF THE INVENTION

Relates to a camera recorder.

2. The technical problem to be solved by the invention

An adaptive camera recorder capable of adaptively recording a subject image signal according to a change amount of a subject image signal is implemented.

3. Summary of Solution to Invention

An adaptive camera recorder according to the present invention includes an image pickup unit for picking up an object and generating an optical signal and a video signal of the picked-up subject, a signal processing unit for encoding the video signal and converting the video signal into a television signal, A delay unit for delaying one frame data, a subtractor for obtaining a difference between one frame data delayed by the delay unit and current frame data of the television signal and outputting the difference signal as a detection signal representing a change amount of the television signal; A voltage controlled oscillator for oscillating a signal having a frequency corresponding to the amount of change of the detection signal, a counter for sequentially counting a signal having the oscillated frequency, and a voltage value of the counted signal equal to a predetermined reference voltage value Control the recording period of the television signal when the counted signal And a comparator generated as a recording period control signal for recording, and a recording section for recording the television signal converted by the signal conversion section in accordance with the recording period control signal on a recording medium.

4. Important uses of the invention

Surveillance camera recorder

Description

Adaptive camera recorder

1 is a block diagram of a general surveillance camera recorder.

2 is a block diagram of an adaptive surveillance camera recorder according to the present invention.

FIG. 3 is a detailed configuration diagram of an image signal variation detector and an adaptive control signal generator in FIG.

4 is an operation timing diagram of signals processed by an image signal variation detector and an adaptive control signal generator in FIG.

* Explanation of symbols for main parts of the drawings

2: imaging unit 4: signal processing unit

6: recording unit 8: recording medium

10: control unit 20: video signal change detection unit

22: frame memory 24: subtractor

26: low pass filter 30: adaptive control signal generator

32: voltage controlled oscillator 34: counter

36: comparator

The present invention relates to a camera recorder, and more particularly, to a camera recorder for adaptively recording a subject video signal according to a change amount of a subject video signal.

In general, a camera recorder configured as shown in FIG. 1 converts an optical image of a subject formed through a lens into an electrical signal, and records the converted electrical signal on a recording medium. That is, the imaging unit 2 causes the optical image of the subject to be combined using a lens, and the signal processing unit 4 converts the combined optical image into an electrical signal. The recording section 6 then converts the electrical signal from the signal processing section 4 into a signal that can be optimally recorded on the recording medium 8 such as magnetic tape so that the converted signal is recorded on the recording medium 8. At this time, the control unit 10 receives a control signal for the imaging unit 2, the signal processing unit 4 and the recording unit 6 to perform the above-described series of operations. 6) Provide to each.

On the other hand, when the camera recorder having the configuration as shown in FIG. 1 is used for monitoring, the recording medium 8 has a capacity limitation. Therefore, the control unit 10 samples the electric signal of the subject at regular time intervals to record the interval. To be At this time, the same amount of information is recorded on the recording medium 8 regardless of whether the current situation does not need to be monitored or the situation needs to be monitored in great detail. Such a recording method has a problem of acting as a wasteful element in terms of a recording medium having a limited capacity.

Accordingly, an object of the present invention is to provide an adaptive camera recorder for adaptively recording a subject image signal according to a change amount of a subject.

Another object of the present invention is to provide an adaptive camera recorder having a cycle for recording a subject image signal according to a change amount of a subject.

It is still another object of the present invention to provide an adaptive camera recorder which efficiently uses a recording medium.

According to the above objects, the present invention can detect the amount of change in the image signal of the subject to be imaged, and set the sampling frequency for determining the interval of the interval recording according to the amount of change so that the recording can be adapted to the change in the image signal. Towards an adaptive camera recorder.

An adaptive camera recorder according to the present invention includes an image pickup unit for picking up an object and generating an optical signal and a video signal of the picked-up subject, a signal processing unit for encoding the video signal and converting the video signal into a television signal, A delay unit for delaying one frame data, a subtractor for obtaining a difference between one frame data delayed by the delay unit and current frame data of the television signal and outputting the difference signal as a detection signal representing a change amount of the television signal; A voltage controlled oscillator for oscillating a signal having a frequency corresponding to the amount of change of the detection signal, a counter for sequentially counting a signal having the oscillated frequency, and a voltage value of the counted signal equal to a predetermined reference voltage value Control the recording period of the television signal when the counted signal Is composed of a comparator for generating a recording period signal for control group, a recording section for recording on a recording medium said television signal converted by the signal converting unit in accordance with the write control signal period.

DETAILED DESCRIPTION A detailed description of preferred embodiments of the present invention will now be described with reference to the accompanying drawings.

FIG. 2 is a block diagram of the adaptive surveillance camera recorder according to the present invention, and the detailed configuration of the video signal change detection unit 20 and the adaptive control signal generator 30 is shown in FIG. Is shown.

2 and 3, the imaging unit 2 captures an image of a subject to generate an optical signal, and converts the generated optical signal as an electric image signal. The signal processing section 4 encodes the video signal produced by the imaging section 2 into the luminance signal Y, the color signal C, the composite video signal Y + C, or the like, so that the television signal a is output.

The signal change detection unit 20 is for detecting the change amount of the television signal a, and is composed of a frame memory 22, a subtractor 24 and a low pass filter 26 as shown in FIG. The input frame a (Yn) is compared with the data b (Yn + 1) before the input frame, and the difference component is separated and low pass filtered to detect the change d.

The adaptive control signal generator 30 generates a signal h for controlling an interval of recording time corresponding to the signal d detected by the signal change amount detector 20. That is, when the amount of change in the subject is large, the output voltage value of the signal d detected by the signal change amount detecting unit 20 becomes large, and the signal is applied to the voltage controlled oscillator 32 to generate a signal e having a high frequency. . The counter 34 then counts the signal e output from the voltage controlled oscillator 32 so that the counted signal is applied as one input signal f of the comparator 36.

On the other hand, the comparator 36 receives the reference voltage Vref having a predetermined reference voltage value as the other input signal g, and the voltage level of the input signal f is equal to the voltage level of the input signal g. If the signal (h) is output. At this time, the signal h is not only applied to the control unit 10 as a recording start signal but also as a reset signal RST of the counter 34 so that the counter 34 overlaps counting from the moment when the recording start signal is output. The recording interval is adaptively performed.

The recording section 6 converts various television signals output from the signal processing section 4 as optimal signals that can be recorded on the recording medium 8. The recording medium 8 is a medium capable of storing information, for example, a magnetic tape, an optical disk, a semiconductor memory, or the like.

The system controller 10 captures a subject and converts it into a video signal, and generates a series of all control signals necessary for converting the converted video signal into a television signal suitable for recording on the recording medium 8 to capture the image. ), The signal processing section 4 and the recording section 6, respectively. In this case, an interval period determination signal i may be applied to the recording unit 6 to control when interval recording is required. Then, the recording interval changes according to the signal h output from the adaptive control signal generator 30.

The operation timing diagrams of the signals processed by the signal change amount detecting unit 20 and the adaptive control signal generating unit 30 of the adaptive camera recorder performing the above-described series of operations are shown in FIGS. 4A and 4B. Is also shown in the figure.

Referring to FIGS. 2 to 4 (a), the signal b (Yn + 1) output from the frame memory 22 of the signal change amount detecting unit 20 is the signal a (Yn) applied from the signal processing unit 4. Is a signal delayed by one frame, and the signal c output from the subtractor 24 is a signal determined as shown in FIG. 4 (a) as the difference and absolute value of these two data are taken. At this time, signal c is lowpass filtered and then output as signal d. The voltage controlled oscillator 32 oscillates a signal e having a frequency proportional to the signal d which is the output of the signal change amount detecting unit 20. In FIG. 4 (a), the section “TA” represents a case where the oscillation frequency of the voltage controlled oscillator 32 is low due to the small amount of change of the subject, and the section “TB” represents a medium change of the subject. "TC" represents a case where the oscillation frequency is very high as the amount of change of the subject is very large.

Referring to FIGS. 2, 3 and 4 (b), the counter 34 clocks the signal e from the voltage controlled oscillator 32 and the output signal h of the comparator 36. The reset signal RST always counts periodically from 0 to the reference value X. The comparator 36 receives the reference voltage Vref having the reference value X as one input signal g, and compares the two signals by comparing the signal f from the counter 34 with the other input signal. Whenever this value becomes the same, the same signal as h is output. This output signal h is used as the reset signal RST of the counter 34, whereby the counter 34 counts up to the reference value X of the comparator 36. In addition, the signal h output from the comparator 36 is also applied to the control unit 10 which generates a signal i for allowing interval recording.

Then, the controller 10 generates an i signal proportional to the output signal h of the adaptive control signal generator 30 and uses it as a control signal for interval recording. At this time, the interval recording period is “Ta”, “Tb” and “Tc” as shown in FIG. 4 (b). In the section where the subject has little change, “Ta” and in the section where the recording interval is long and the change has a large amount The recording interval is shortened as in “Tc”. That is, the recording unit 6 receives the signal i for controlling the interval recording and records a lot of information when the amount of change in the subject is large, and records little information when the amount of change in the subject is small. In FIG. 4 (b), the reference numeral “T1” denotes a section to be recorded by the signal i for controlling interval recording, and “T2”, “T3” and “T4” denote a section to which no recording is made. .

As described above, it is possible to check a situation that requires detailed recording by detecting the change amount of the subject so that the recording interval is changed, and in the case where detailed recording is not required, it is possible to efficiently use the recording medium by adjusting the recording interval. have.

Claims (3)

A camera recorder for converting and recording an optical signal of a subject into a television signal, comprising: an imaging unit for photographing a subject to generate an optical signal and a video signal of the photographed projectile; and a signal processing unit for encoding the video signal and converting the video signal into a television signal. A delay unit for delaying one frame data of the television signal, a difference between one frame data delayed by the delay unit and current frame data of the television signal, and detecting the difference signal representing an amount of change of the television signal. A subtractor for outputting a signal, a voltage controlled oscillator for oscillating a signal having a frequency corresponding to the change amount of the detection signal, a counter for sequentially counting the signal having the oscillated frequency, and a voltage value of the counted signal is predetermined If the reference voltage value is equal to the counted signal And a comparator generated as a recording period control signal for controlling the recording period of the television signal, and a recording unit for recording the television signal converted by the signal conversion section in accordance with the recording period control signal on a recording medium. Adaptive camera recorder. 2. The adaptive camera recorder of claim 1, further comprising a low pass filter for low pass filtering the difference signal from the subtractor to output a low pass filtered signal to the voltage controlled oscillator. The adaptive camera recorder of claim 1, wherein the delay unit is a frame memory that stores one frame data of the television signal.