JP2004200989A - Imaging apparatus and supervisory system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging apparatus capable of realizing the improvement of security when being used for a supervisory system while suppressing increase in an amount of dynamic image data. <P>SOLUTION: In the imaging apparatus 12 for imaging a supervisory object part, a motion detection / compensation section 56 of a dynamic image compression section 30 detects a motion vector, and a TG control section 34 comparatively extends a period of a synchronizing signal supplied from a timing generator 24 to an imaging section 20 so as to decrease an imaging frame rate by the imaging section 20 in a low image quality mode when the motion vector is detected for a period less than a prescribed period, and comparatively decreases the period of the synchronizing signal to increase the imaging frame rate in a high image quality mode when the motion vector is detected for a period being the prescribed period or over. Encoded dynamic image data compressed via the dynamic image compression section 30 are transmitted to a management center 14 via a communication channel 16 and a display apparatus 64 displays the data as a dynamic image. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a photographing apparatus and a monitoring system, and more particularly to a photographing apparatus suitable for automatic photographing of moving images and a monitoring system including the photographing apparatus.
[0002]
[Prior art]
Conventionally, a monitoring camera is installed at a location to be monitored for the purpose of crime prevention, etc., and a moving image obtained by photographing with the monitoring camera is transmitted via a communication line, and is installed at a location away from the location to be monitored. There is known a monitoring system that enables remote monitoring of a portion to be monitored by displaying on a monitor or the like. Further, as techniques applicable to this type of monitoring system, for example, techniques listed below have been proposed.
[0003]
That is, for example, in Patent Document 1, the movement of an image within a set attention area is detected from input images, and when the detected amount of motion does not exceed a set value, only the attention area is processed and the set value is exceeded. In such a case, there has been proposed an image signal generation device that processes the entire screen to suppress the data amount of the moving image to be transmitted and prevent the disturbance of the moving image.
[0004]
Also, for example, in Patent Document 2, a moving image for a predetermined time in a monitoring area is circulated and stored, and a line is connected when the amount of motion (sum of absolute values of motion vectors) in the monitoring area is larger than a predetermined value. There is also a monitoring device that connects and records high-definition still images, and enables the management center to reproduce moving images and still images when the amount of motion is greater than a predetermined value, and moving images for a predetermined time just before that. Proposed.
[0005]
Further, for example, in Patent Document 3, a MOS-type image pickup device is used to detect a motion of an object from the captured image, and only image data in a recording area determined based on the result of the motion detection is recorded on the recording medium. A surveillance camera that realizes a reduction in the capacity of a recording medium by recording on the recording medium has been proposed.
[0006]
Furthermore, for example, in Patent Document 4, it is determined whether or not a person has entered and exited the monitoring area based on a motion vector obtained from a photographed image. There has also been proposed a technique for recording video during a period from when the user leaves the room until a predetermined time elapses.
[0007]
[Patent Document 1]
JP-A-8-46909
[Patent Document 2]
JP-A-10-42275
[Patent Document 3]
JP-A-11-27654
[Patent Document 4]
Japanese Patent Laid-Open No. 11-45379
[0008]
[Problems to be solved by the invention]
Each of the above-described technologies controls the range to be processed, connection of lines (transmission of images), the area to be recorded on the recording medium, and start / stop of recording based on the detection result by the motion detection process. However, the motion detection process is a process of comparing the feature amount (for example, a motion vector) corresponding to the motion amount of the moving object on the image with a threshold to determine the presence or absence of motion, whereas the value of the feature amount is large. The length varies depending on the distance between the moving object and the image sensor within the shooting range (the size of the moving object on the image), lighting conditions, and so on. Despite being within the range, there is a possibility that the feature amount corresponding to the motion amount is less than the threshold value, so that it may be erroneously determined that there is no motion. There may be a possibility that an image is not recorded or only partially recorded. For this reason, it is necessary to take new measures for improving the security of the monitoring system.
[0009]
The present invention has been made in consideration of the above-described facts, and it is possible to obtain an imaging device capable of realizing an improvement in security when used in a monitoring system while suppressing an increase in the amount of moving image data. This is the first purpose.
[0010]
The second object of the present invention is to obtain a monitoring system that can improve security.
[0011]
[Means for Solving the Problems]
In order to achieve the first object, the imaging apparatus according to the first aspect of the present invention is based on imaging means for continuously imaging a subject, and based on moving image data obtained by imaging by the imaging means. Detecting means for detecting the movement of the subject imaged by the means, and at least one of the frame rate and the resolution of the moving image data to be output while the movement of the subject is not detected by the detecting means. And a control unit that changes a frame rate in imaging by the imaging unit or processes and outputs moving image data obtained by imaging by the imaging unit.
[0012]
The invention described in claim 1 is provided with an imaging unit that continuously images the subject, and the detection unit is configured to detect the subject imaged by the imaging unit based on the moving image data obtained by the imaging by the imaging unit. Detect motion. Note that the detection unit specifically calculates, for example, a feature amount (for example, a motion vector) representing the motion of the subject based on the difference between the images of adjacent frames among the moving images obtained by the imaging unit. By comparing the calculated feature amount with a threshold value, it can be configured to detect the presence or absence of movement of the subject.
[0013]
Further, the control means according to the first aspect of the present invention provides the frame rate of the moving image data (moving image data output from the photographing apparatus according to the present invention) to be output while the movement of the subject is not detected by the detecting means. The frame rate in imaging by the imaging unit is changed or the moving image data obtained by imaging by the imaging unit is processed and output so that at least one of the resolution (number of pixels or number of gradations) decreases.
[0014]
Note that changing the frame rate in imaging by the imaging unit so that the frame rate of the moving image data to be output is reduced, for example, as described in claim 2, so that the frame rate in imaging by the imaging unit is reduced. This can be realized by changing the period of the synchronization signal supplied to the imaging means. Further, the processing of the moving image data so that the frame rate of the moving image data to be output is reduced is, for example, as described in claim 3, out of each frame of the moving image data obtained by imaging by the imaging unit. This can be realized by periodically decimating some frames. Further, the processing of the moving image data so that the resolution of the moving image data to be output is reduced is, for example, as described in claim 4, a part of each frame of the moving image data obtained by imaging by the imaging unit. This can be realized by regularly thinning out the pixels.
[0015]
While the movement of the subject is detected by the detection means, the importance of the moving image is higher than when the movement of the subject is not detected (for example, in the monitoring system, there is an object to be monitored). However, during this period, as described above, at least one of the frame rate and resolution of the moving image data is increased, so that the image quality is improved. On the other hand, while the movement of the subject is not detected by the detection means, at least one of the frame rate and resolution of the moving image data output from the imaging device is reduced, so that the data amount of the moving image data is reduced and the moving image data is reduced. An increase in the amount of data as the entire image data can be suppressed.
[0016]
In addition, considering that there is a case where sufficient accuracy may not be obtained in the detection by the detection unit as described above, a scene having high importance in the moving image while the movement of the subject is not detected by the detection unit May be mixed. On the other hand, in the first aspect of the invention, the data amount can be reduced by reducing at least one of the frame rate and the resolution of the moving image data during this period. There is no need to discard the moving image data without outputting it, or to output only moving image data corresponding to a part of the imaging range. Therefore, even when a highly important scene is mixed in the moving image while the movement of the subject is not detected by the detection means, the image quality of the moving image is reduced by reducing at least one of the frame rate and the resolution. Although it is relatively low, a moving image corresponding to the scene is also output.
[0017]
As described above, the imaging apparatus according to the first aspect of the invention outputs the moving image data while the movement of the subject is not detected by the detecting unit while suppressing the increase in the data amount of the moving image data to be output. Therefore, it is suitable for a monitoring system and can improve security when used in the monitoring system.
[0018]
According to a fifth aspect of the present invention, there is provided a monitoring system that receives the imaging apparatus according to any one of the first to fourth aspects and moving image data output from the imaging apparatus via a communication line, Display / recording control means for displaying the moving image data as a moving image on the display means or recording it on a recording medium.
[0019]
Since the invention described in claim 5 includes the imaging device according to any one of claims 1 to 4, the imaging is performed even when the movement of the subject is not detected by the detection means of the imaging device. Moving image data is output from the apparatus. The display / recording control unit receives the moving image data output from the photographing apparatus via the communication line, and displays the received moving image data as a moving image on the display unit or records it on a recording medium. Can be improved. In addition, since an increase in the amount of moving image data output from the photographing apparatus is suppressed, a low-speed and low-cost communication line can be used as a communication line for transmitting and receiving moving image data, and the cost of the monitoring system is reduced. (At least one of initial cost and running cost) can be suppressed.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a monitoring system 10 according to the present embodiment. The monitoring system 10 is configured by connecting a plurality of imaging devices 12 installed at a location to be monitored and a management center 14 via a communication line 16. The monitoring system 10 corresponds to the monitoring system described in claim 5.
[0021]
Since the plurality of imaging devices 12 have the same configuration, the configuration will be described below using the single imaging device 12 as an example. The imaging device 12 corresponds to the imaging device according to the present invention, and incorporates an imaging unit 20 including an area CCD as an imaging element. A lens 22 for forming an image of the subject on the light receiving surface of the imaging device is disposed on the light incident side of the imaging device of the imaging unit 20. As the lens 22, for example, a lens provided with a mechanism (autofocus (AF) mechanism) capable of changing a focal position by a driving force of a driving source such as a stepping motor can be used.
[0022]
A timing generator 24 that generates a timing signal is connected to the imaging device of the imaging unit 20, and the imaging device is driven in a cycle synchronized with the timing signal generated by the timing generator 24. As a result, a moving image signal (image signal (single signal indicating the total amount of received light within a predetermined charge accumulation period in each of a large number of photoelectric conversion cells arranged in a matrix on the light receiving surface of the image sensor) is output from the image sensor. An image signal corresponding to one frame image) is sequentially output at the same cycle (frame rate) as that of the timing signal. The imaging unit 20 includes a signal processing unit. The signal processing unit amplifies or whites an analog moving image signal output from the imaging device in units of image signals corresponding to individual frame images. Correct the balance.
[0023]
An A / D converter 26, a signal processing unit 28, and a moving image compression unit 30 are connected in order to the signal output terminal of the imaging unit 20. The analog moving image signal output from the imaging unit 20 is converted into digital moving image data by the A / D converter 26 and input to the signal processing unit 28. The signal processing unit 28 performs various processes such as color correction and γ correction on the input moving image data in units of data corresponding to the sequentially input frame images. The moving image data that has been subjected to various processes by the signal processing unit 28 is sequentially input to the moving image compression unit 30.
[0024]
The photographing apparatus 12 also includes a CPU 32. Although not shown, the CPU 54 includes peripheral circuits such as a ROM, a RAM, and an input / output port. 1 are connected to the CPU 32 via a bus (not shown), and the operation of each processing block is performed by the CPU 32. Each is controlled.
[0025]
On the other hand, the moving image compression unit 30 compresses (encodes) the input moving image data. Various known methods can be adopted as the moving image compression method in the moving image compression unit 30, but the configuration will be described below by taking as an example the case of compressing a moving image using the MPEG2 (Moving Picture Experts Group phase 2) method. To do. The moving image compressing unit 30 includes a subtractor 40 and a motion detection / compensation unit 56. The moving image data input to the moving image compressing unit 30 includes the subtracter 40 and the data corresponding to individual frame images. Each is input to the motion detection / compensation unit 56.
[0026]
A memory 54 is connected to the motion detection / compensation unit 56, and data (described later) of prediction reference images is stored in the memory 54. The motion detection / compensation unit 56 detects a motion vector by comparing the current frame image represented by the data input from the signal processing unit 28 with the prediction reference image represented by the data stored in the memory 54.
[0027]
More specifically, the motion vector detection is performed by dividing the input current frame image into a plurality of blocks and searching for each block set on the prediction reference image as shown in FIG. By repeating the error calculation while appropriately moving the block to be searched within the range, the block most similar to the block to be searched (the block with the smallest error) is searched from the search range, and the block and the block to be searched are The shift amount and the shift direction are set as motion vectors for the searched block. A motion vector that minimizes the prediction difference in predictive coding can be obtained by combining the motion vector obtained for each block in consideration of the error for each block.
[0028]
In addition, the motion detection / compensation unit 56 generates prediction image data by performing motion compensation on the prediction reference image based on the detected motion vector, and outputs the prediction image data to the subtractor 40. The subtracter 40 subtracts the prediction image represented by the data input from the motion detection / compensation unit 56 from the current frame image represented by the data input from the signal processing unit 28, thereby obtaining difference data representing the prediction difference. Generate.
[0029]
A DCT (discrete cosine transform) unit 42, a quantization unit 44, and an encoding unit 46 are sequentially connected to the subtracter 40. The DCT unit 42 orthogonally transforms the difference data input from the subtractor 40 for each arbitrary block and outputs the result. The quantization unit 44 converts the difference data input from the DCT unit 42 into the predetermined quantum data. The data is quantized at the encoding step and output to the encoding unit 46. In addition, a motion detection / compensation unit 56 is connected to the encoding unit 46, and motion vector data is also input from the motion detection / compensation unit 56. The encoding unit 46 encodes the difference data that has undergone orthogonal transform / quantization using a two-dimensional Huffman code, encodes input motion vector data using a Huffman code, multiplexes both, and encodes moving image data. Output as.
[0030]
On the other hand, an inverse quantization unit 48, an inverse DCT unit 50, and an adder 52 are sequentially connected to the quantization unit 44. The difference data that has undergone orthogonal transformation / quantization is output from the quantization unit 44 to the inverse quantization unit 48, and after inverse quantization is performed by the inverse quantization unit 48, inverse orthogonal transformation is performed by the inverse DCT unit 50. Thus, it is reproduced (restored) as difference data and input to the adder 52. In addition, a motion detection / compensation unit 56 and a memory 54 are also connected to the adder 52, and predicted image data is input from the motion detection / compensation unit 56. The adder 52 generates the reference image data for prediction by adding the reproduced difference data and the predicted image data, and stores it in the memory 54. The prediction reference image data stored in the memory 54 is used for predictive coding for the next frame image.
[0031]
The motion detection / compensation unit 56 is connected to the timing generator 24 via the timing generator (TG) control unit 34, and motion vector data is input from the motion detection / compensation unit 56 to the TG control unit 34. The The TG control unit 34 is connected to the timing generator 24, and the cycle of the timing signal generated by the timing generator 24 is determined by the TG control unit 34 based on the motion vector data input from the motion detection / compensation unit 56. Be controlled.
[0032]
A communication control unit 36 is connected to the image data output terminal of the encoding unit 46. The communication control unit 36 is connected to the communication line 16, and the encoded moving image data input from the encoding unit 46 is transmitted to the management center 14 via the communication line 16.
[0033]
Further, the management center 14 includes a communication control unit 60 connected to the communication line 16, and the encoded moving image data transmitted from the imaging device 12 is received by the communication control unit 60 via the communication line 16. An image display control unit 62 and an image recording control unit 66 are connected to the communication control unit 60. A display 64 is connected to the image display control unit 62, and the image display control unit 62 decodes the encoded moving image data received by the communication control unit 60 and displays it on the display 64 as a moving image. The image recording control unit 66 is connected to a storage device 68 such as a hard disk drive (HDD), and the encoded moving image data received by the communication control unit 60 is stored in the storage device 68. The image display control unit 62 and the image recording control unit 66 correspond to the display / recording control means described in claim 5.
[0034]
Next, the operation of this embodiment will be described. The photographing apparatus 12 according to the present embodiment is provided with a low image quality mode and a high image quality mode as image quality modes, and the TG control unit 34 has a timing signal cycle (frame rate) generated by the timing generator 24. As the setting value, a setting value corresponding to the low image quality mode and a setting value corresponding to the high image quality mode are stored in advance. Note that the setting value corresponding to the low image quality mode is determined so that the cycle of the timing signal is longer (the frame rate is lower) than in the high image quality mode.
[0035]
When the photographing apparatus 12 is turned on, the TG control unit 34 reads a setting value corresponding to the low image quality mode from the two setting values, and a timing signal having a period corresponding to the read setting value is output to the timing generator 24. The timing generator 24 is controlled so that As a result, the moving image signal output from the imaging unit 20 is a signal in which image signals corresponding to each frame image are sequentially output in a relatively long cycle, as shown as “low frame rate” in FIG. It becomes.
[0036]
The moving image signal output from the imaging unit 20 is input to the moving image compression unit 30 as digital moving image data via the A / D converter 26 and the signal processing unit 28, and motion detection / motion of the moving image compression unit 30 is detected. In the compensation unit 56, motion vector detection / prediction image data generation is performed for each frame image data sequentially input as described above. The motion vector detected by the motion detection / compensation unit 56 is used. Is sequentially input to the TG control unit 34 (and the encoding unit 46).
[0037]
The TG control unit 34 compares the motion vector represented by the data input from the motion detection / compensation unit 56 with a predetermined value, and determines whether the subject (within the imaging range by the imaging unit 20) is based on whether the motion vector is greater than or equal to the predetermined value. It is determined whether or not there is any movement in the object existing in As a motion vector to be compared with a predetermined value, for example, an absolute value of a motion vector can be used. Alternatively, a motion vector for each block used for detecting a motion vector may be used. When the motion vector is less than the predetermined value, the timing generator 24 is controlled so that the cycle of the timing signal generated by the timing generator 24 continues with the cycle corresponding to the low image quality mode.
[0038]
Therefore, while the movement of the subject is not detected, the period of the timing signal supplied to the imaging unit 20 is lengthened and the frame rate in imaging by the imaging unit 20 is reduced as compared with the high image quality mode described later. Thus, the data amount of the moving image data (encoded moving image data) output from the signal processing unit 28 and output from the imaging device 12 via the moving image compression unit 30 is suppressed.
[0039]
Further, in the TG control unit 34, when the motion vector represented by the data input from the motion detection / compensation unit 56 exceeds a predetermined value, it can be determined that the subject has moved, so the TG control unit 34 The timing generator 24 is controlled so that a setting value corresponding to the high image quality mode is read and a timing signal having a period corresponding to the read setting value is generated by the timing generator 24. As a result, the moving image signal output from the imaging unit 20 is a signal in which image signals corresponding to each frame image are sequentially output in a relatively short cycle, as indicated by “high frame rate” in FIG. It becomes.
[0040]
Since the TG control unit 34 controls the timing generator 24 so that the period of the timing signal generated by the timing generator 24 continues with the period corresponding to the high image quality mode while the motion vector is equal to or greater than a predetermined value. While the movement of the subject is detected, the period of the timing signal supplied to the imaging unit 20 is shortened and the frame rate in imaging by the imaging unit 20 is increased as compared with the low image quality mode described above. Thus, although the amount of moving image data (encoded moving image data) output from the signal processing unit 28 and output from the imaging device 12 via the moving image compression unit 30 increases, the image quality is improved. .
[0041]
The encoded moving image data transmitted from the imaging device 12 is displayed as a moving image on the display 64 of the management center 14 and the monitored portion is monitored by being visually recognized by a monitor, but the motion vector is a predetermined value or more. The period (period in which the movement of the subject is detected) is a period in which there is a high possibility that an object to be monitored exists in the monitoring target location, and the moving image corresponding to this period is the monitoring of the monitoring target location. It is estimated that the degree of importance is high (for example, for a monitoring system). In the monitoring system 10 according to the present embodiment, high-quality moving images can be provided during the above-described period, so that the monitoring accuracy can be improved.
[0042]
In addition, since the magnitude of the motion vector depends on the distance between the moving object and the photographing apparatus 12 and the illumination condition of the object, it is important for a moving image captured during a period when the motion vector is less than a predetermined value. There is a possibility that scenes with high degrees are mixed. In contrast, the imaging device 12 according to the present embodiment suppresses an increase in the amount of moving image data by setting the image quality mode to the low image quality mode even during a period in which the motion vector is less than the predetermined value. Since imaging / moving image output is continued, even when a highly important scene is mixed in a moving image captured during a period when the motion vector is less than a predetermined value, the scene is viewed as a moving image. Therefore, the security of the monitoring system 10 is improved.
[0043]
In the monitoring system 10 described above, the process of comparing the motion vector with a predetermined value in the process performed by the TG control unit 34 and determining the presence or absence of the motion of the subject is performed together with the motion detection / compensation unit 56 that detects the motion vector. Corresponding to the detection means of the invention, the processing for controlling the cycle of the timing signal among the processing performed by the TG control unit 34 corresponds to the control means of the present invention (specifically, the control means according to claim 2). Yes.
[0044]
In the above description, the example in which the switching of the image quality mode is realized by switching the cycle of the timing signal supplied to the imaging unit 20, but the present invention is not limited to this. As an example, FIG. 4 shows another configuration of the monitoring system. In the monitoring system 10 (FIG. 1) described above, data representing a motion vector is input from the motion detection / compensation unit 56 to the TG control unit 34. However, in the monitoring system 70 shown in FIG. Instead, the motion detection / compensation unit 56 and the signal processing unit 28 are connected, and data representing a motion vector is input to the signal processing unit 28.
[0045]
In the monitoring system 70, the signal processing unit 28 compares the motion vector represented by the data input from the motion detection / compensation unit 56 with a predetermined value, and corresponds to the low image quality mode when the motion vector is less than the predetermined value. As processing, by periodically thinning out data of some pixels from the data of each frame image input from the A / D converter 26, “low resolution” is shown as an example in FIG. 5. As described above, the resolution of each frame image is reduced. Thereby, during the period when the motion vector is less than the predetermined value, the data amount of the encoded moving image data output from the signal processing unit 28 and output from the imaging device 12 via the moving image compression unit 30 is suppressed. become.
[0046]
In addition, during a period in which the motion vector is equal to or greater than a predetermined value, the signal processing unit 28 is input from the A / D converter 26 in order to improve the image quality of the moving image represented by the moving image data corresponding to the high image quality mode. The process of thinning out some pixel data from each frame image data is stopped. As a result, the number of pixels of each frame image is increased as compared with the period of the low image quality mode, and the moving image represented by the moving image data is improved in image quality, as shown as “high resolution” in FIG. 5 as an example. Is done. Also in the monitoring system 70 configured as described above, it is possible to improve the monitoring accuracy during a period in which the motion vector is equal to or greater than a predetermined value (period of the high image quality mode), and to improve the security of the monitoring system 70. In the above-described monitoring system 70, among the various processes performed by the signal processing unit 28, the process of thinning out the data of some pixels corresponds to the control means of the present invention (specifically, the control means described in claim 4). doing.
[0047]
In the above description, an example in which the resolution is reduced by regularly thinning out some pixel data from the data of each frame image has been described. However, the present invention is not limited to this. Decrease the number of gradations of each pixel (for example, if the original data is data representing the density and color of each pixel in 8 bits each of R, G, B, the density and color of each pixel is R, G, It is also possible to reduce the resolution (lower image quality) of a moving image by converting the data into data represented by 7 bits or less (for example, 4 bits) for each B. The resolution reduction processing in this aspect also corresponds to the control means of the present invention (specifically, the control means described in claim 4).
[0048]
In the monitoring system 10 (FIG. 1), the case where the frame rate of the moving image is switched by switching the cycle of the timing signal supplied to the imaging unit 20 has been described. However, the present invention is not limited to this. As in the monitoring system 70 shown in FIG. 4, data representing a motion vector is input from the motion detection / compensation unit 56 to the signal processing unit 28. In the signal processing unit 28, the motion vector is less than a predetermined value. In this case, the frame rate of the moving image may be lowered by periodically thinning out data of some of the frame images input from the A / D converter 26. The processing for reducing the frame rate in this aspect also corresponds to the control means of the present invention (specifically, the control means described in claim 3).
[0049]
Furthermore, in the above description, the mode in which only one of the reduction of the frame rate of the moving image and the reduction of the resolution of the moving image is described in the low image quality mode is not limited to this. May be. Further, the degree to which the frame rate of the moving image is reduced and the degree to which the resolution of the moving image is reduced may be switched stepwise or continuously according to the magnitude of the motion vector.
[0050]
In the above, when the motion vector changes from less than a predetermined value to more than a predetermined value, or when the motion vector changes from more than a predetermined value to less than a predetermined value, the image quality mode is immediately switched. However, the present invention is limited to this. Instead, as shown in FIG. 6 as an example, when the motion vector is equal to or higher than the first predetermined value, the mode is switched to the high image quality mode, and the motion vector is less than the second predetermined value (<first predetermined value). In this case, by switching to the low image quality mode, a dead zone (the range of the first predetermined value to the second predetermined value in the example of FIG. 6) in which the image quality mode is not switched may be provided.
[0051]
【The invention's effect】
As described above, the imaging apparatus according to the present invention detects the movement of the subject based on the moving image data obtained by continuous imaging of the subject by the imaging unit, and outputs while the movement of the subject is not detected. Since the frame rate is changed in the imaging or the moving image data is processed so that at least one of the frame rate and the resolution of the moving image data is reduced, the increase in the data amount of the moving image data is suppressed, and the monitoring system is It has an excellent effect that security can be improved when used.
[0052]
The monitoring system according to the present invention includes the imaging device according to the present invention, receives moving image data output from the imaging device via a communication line, and displays the moving image data as a moving image on a display unit or on a recording medium. Since it is recorded, it has the outstanding effect that security can be improved.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a schematic configuration of a monitoring system according to an embodiment.
FIG. 2 is a conceptual diagram for explaining a process of detecting a motion vector.
FIG. 3 is a conceptual diagram for explaining a mode in which the frame rate is switched between a case where motion is detected and a case where motion is not detected.
FIG. 4 is a block diagram illustrating another example of a schematic configuration of a monitoring system.
FIG. 5 is a conceptual diagram for explaining a mode of switching resolution between a case where motion is detected and a case where motion is not detected.
FIG. 6 is a diagram showing another example of the switching timing between the high image quality mode and the low image quality mode.
[Explanation of symbols]
10 Monitoring system
12 Imaging device
14 Management Center
16 Communication line
20 Imaging unit
24 Timing generator
28 Signal processor
30 Video compression unit
34 TG control unit
56 Detector / Compensator
62 Image display controller
64 display
66 Image recording controller
68 Storage device
70 Monitoring system

Claims (5)

Imaging means for continuously imaging a subject;
Detection means for detecting movement of a subject imaged by the imaging means based on moving image data obtained by imaging by the imaging means;
While the movement of the subject is not detected by the detection unit, the frame rate in the imaging by the imaging unit is changed or the imaging is performed so that at least one of the frame rate and the resolution of the moving image data to be output is reduced. Control means for processing and outputting moving image data obtained by imaging by means;
An imaging device including: The control means reduces the frame rate of the moving image data to be output by changing a period of a synchronization signal supplied to the imaging means so that a frame rate in imaging by the imaging means is reduced. The photographing apparatus according to claim 1. The control means, as the processing of the moving image data, periodically thins out some of the frames of the moving image data obtained by the imaging by the imaging means, thereby outputting the moving image frames The photographing apparatus according to claim 1, wherein the rate is lowered. The control means reduces the resolution of the output moving image by regularly thinning out some pixels in each frame of the moving image data obtained by imaging by the imaging means as the processing of the moving image data. The photographing apparatus according to claim 1, wherein: An imaging device according to any one of claims 1 to 4,
Display / recording control means for receiving the moving image data output from the photographing apparatus via a communication line and displaying the received moving image data as a moving image on a display means or recording it on a recording medium;
Including monitoring system.

Images