JP2022030809A - Imaging system, method for controlling imaging system, and program - Google Patents

Abstract

To provide a technique to adjust a driving speed according to a vibration environment so as to prevent step out of a motor in the vibration environment.SOLUTION: An imaging system comprises: an imaging unit that picks up an image of a subject; a driving unit that drives the components of the imaging unit; prediction means that predicts vibration of the imaging unit; determination means that, based on the predicted vibration, determines a drive condition for driving the driving unit; and drive control means that drives the driving unit in accordance with the determined drive condition.SELECTED DRAWING: Figure 1

Description

The present invention relates to an imaging system, a control method of the imaging system, and a program.

Some network cameras for shooting dark areas have a function of shooting a moving image, for example, by removing an infrared cut filter to receive light other than visible light. At that time, it is required to quickly switch the insertion / removal of the infrared cut filter so as not to affect the sound of the moving image. Generally, the insertion / removal of the infrared cut filter is performed by driving a stepping motor. However, it is known that when a stepping motor is mounted on various vehicles such as automobiles and trains having a vibrating environment, the stepping motor and related gears cause step-out. As a result, the period during which the driving sound of the stepping motor is generated becomes long, and the quality of the delivered voice of the network camera deteriorates.

As a method of suppressing the driving noise of the stepping motor, a method of driving the stepping motor by avoiding the resonance point of the stepping motor has been proposed (Patent Document 1). Further, a method has been proposed in which vibration and driving noise are reduced by suppressing a sudden change in the exciting current flowing through the exciting coil of each phase of the stepping motor (Patent Document 2).

Japanese Unexamined Patent Publication No. 2008-11341 Japanese Unexamined Patent Publication No. 2005-204364

However, a technique capable of adjusting the drive speed according to the vibration environment has not been provided so far so as not to cause the motor to step out in the vibration environment.

Therefore, the present invention provides a technique for adjusting the drive speed according to the vibration environment so as not to cause the motor to step out in the vibration environment.

The invention that solves the above problems is an imaging system.
An image pickup unit that captures an image of the subject,
A drive unit that drives the components of the image pickup unit,
A predictive means for predicting vibration of the image pickup unit and
A determining means for determining the driving conditions for driving the driving unit based on the predicted vibration, and
It is provided with a drive control means for driving the drive unit according to the determined drive conditions.

According to the present invention, it is possible to provide a technique for adjusting the drive speed according to the vibration environment so as not to cause the motor to step out in the vibration environment.

The schematic diagram which shows the structural example of the image pickup system corresponding to an embodiment. The flowchart which shows an example of the processing performed by the image pickup system corresponding to an embodiment. The figure which shows an example of the moving state of the image pickup system corresponding to an embodiment. The figure which shows an example of the characteristic of the stepping motor corresponding to the moving state of the image pickup system corresponding to an embodiment, and the figure which shows another example of the characteristic of a stepping motor corresponding to the moving state of an image pickup system. The flowchart which shows the other example of the process which the image pickup system corresponding to an embodiment performs. The figure which shows an example of the frequency characteristic at the time of resonance of the image pickup system corresponding to an embodiment.

Hereinafter, exemplary embodiments will be described with reference to the drawings. The embodiments described below do not limit the inventions described in the claims. Although a plurality of features are described in the embodiment, not all of the plurality of features are essential for the invention, and the plurality of features may be arbitrarily combined. Further, in the attached drawings, the same or similar configurations are given the same reference numbers, and duplicate explanations are omitted.

In the embodiment described below, a network camera is exemplified as the image pickup system, but the present invention is not limited to this, and does not exclude the use of other image pickup devices (for example, a video camera, a still camera, a mobile phone, a mobile information terminal, etc.). do not have. Further, in the embodiment described below, an infrared cut filter is exemplified as a drive target by the stepping motor, but the use is not limited to this, and other drive targets (for example, a zoom lens, a focus lens, an aperture, a pan head, etc.) are used. Does not exclude.

Hereinafter, an example of the embodiment is shown in FIGS. 1 to 6, and the imaging system will be described with reference to the drawings.

[Embodiment 1]
Hereinafter, the first embodiment will be described. In this embodiment, a technique for driving a stepping motor at a driving speed according to the vibration environment will be described so as not to cause the stepping motor to step out in the vibration environment.

FIG. 1 shows an example of the configuration of an imaging system. The image pickup system 10 is configured to include an image processing device 20 and an image pickup device 30, and is connected to a network 40. The image processing device 20 can also be called, for example, an information processing device or a control device. The image pickup system 10 may be, for example, a network camera, a video camera, a still camera, a mobile phone, a mobile information terminal, or the like. The network 40 may be, for example, a wired LAN, a wireless LAN, the Internet, an intranet, or the like.

The image processing device 20 includes a central processing unit (CPU) 100, an input unit 106, a display unit 107, a RAM 108, a ROM 109, a storage unit 110, an interface (I / F) 111, an image analysis unit 112, a compression / expansion unit 113, and a bus 114. , An image processing unit 115, an A / D conversion unit 116, an actuator 117, and an A / D conversion unit 118. Hereinafter, the components of the image processing apparatus 20 will be described in detail.

The CPU 100 controls the overall operation of the image processing device 20. Further, the CPU 100 is configured to function as each functional block of the detection unit 101, the prediction unit 102, the determination unit 103, the drive control unit 104, and the voice processing unit 105. The detection unit 101 can physically and mathematically calculate the speed of the image pickup system 10 based on the acceleration acquired by the sensor 220. The acceleration may be calculated by combining any one or more of, for example, angular velocity, direction, position, and the like. The prediction unit 102 can predict the vibration of the image pickup system 10 by referring to a table such as the vibration of the image pickup system 10 in the RAM 108 or the storage unit 110. However, the prediction of vibration of the imaging system 10 is not limited to the method of referring to a table such as vibration, and for example, the vibration is calculated by applying mathematical approximation calculation such as a spline function or interpolation processing to the registered value of the table. It may be calculated, or vibration may be predicted based on the measured value (acceleration) acquired by the acceleration sensor of the sensor 220.

The determination unit 103 can determine the drive conditions (drive speed and exciting power) for driving the stepping motor based on a table such as vibration in the RAM 108 or the storage unit 110. The drive control unit 104 can control the drive of the drive unit 210 and the actuator 117. The voice processing unit 105 performs predetermined voice processing, such as filtering the voice data acquired by the microphone 240, converted into a digital voice signal by the A / D conversion unit 118, and stored in the RAM 108, to produce voice. Process. Specific voice processing includes, for example, processing such as cutting a signal in a specific band or lowering the level. Further, the voice can be encoded and stored in the storage unit 110 for recording, or the encoded voice data can be decoded and output to a speaker or network 40 (not shown).

The input unit 106 is used for the user to operate the image pickup system 10, and includes, for example, a release switch, an operation key including a power switch, a cross key, a joystick, a touch panel, a keyboard, and a pointing device (for example, a mouse). The display unit 107 displays various inputs or outputs, and is composed of, for example, an LCD display. RAM 108 is a volatile memory such as SRAM and DRAM. ROM 109 is a non-volatile memory such as EEPROM and flash memory. The storage unit 110 is composed of an HDD (hard disk drive), SSD (solid state drive), eMMC (embedded multimedia card), and the like.

The program for realizing the function of the present embodiment and the data for executing the program are stored in the ROM 109 or the storage unit 110. These programs and data are taken into the RAM 108 via the bus 114 and executed by the CPU 100 under the control of the CPU 100.

The interface (I / F) 111 is various interfaces corresponding to inputs or outputs of various signals. The I / F 111 connects to the input unit 106 and receives the user's operation input information via the input unit 106. The I / F 111 transmits the user's operation input information to the CPU 100 via the bus 114. Further, the I / F 111 is connected to a display unit 107 composed of an LCD display or the like, and an image temporarily recorded in the RAM 108 or operation menu information is transmitted to the display unit 107. The I / F 111 connects to the network 40 via a LAN. Based on the image information acquired by the image pickup apparatus 30, the image analysis unit 112 can perform image analysis such as face detection, person detection, motion detection, passage detection, congestion detection, trajectory detection, and abandonment or take-away detection. The image analysis result is notified to the CPU 100 via the bus 114.

The compression / decompression unit 113 performs compression processing on the digital image stored in the RAM 108 based on the control instruction of the CPU 100 via the bus 114 to generate compressed data of the digital image and stores it in the storage unit 110 or the network 40. Can be output to. Further, the compression / decompression unit 113 may perform decompression processing in a predetermined format on the compressed data stored in the storage unit 110 to generate uncompressed data of a digital image, and output the uncompressed data to the display unit 107 via the I / F 111. can. For the compression or decompression processing of a predetermined format, for example, a method compliant with the JPEG standard is used for still images, and for moving images, for example, MOTION-JPEG, MPEG2, AVC / H. 264 and AVC / H. A method conforming to a standard such as 265 is used.

The bus 114 is a data bus or a control bus for connecting each block in the image processing device 20, but is not limited to these, and may be, for example, an address bus, an expansion bus, or the like. The A / D conversion unit 116 can convert the analog image signal acquired by the image pickup device 205 into a digital image signal. The A / D conversion unit 116 transmits a digital image signal to the image processing unit 115. The image processing unit 115 performs various digital image processing on the digital image signal transmitted from the A / D conversion unit 116 based on, for example, AGC (automatic gain control) gain or ISO (international standardization mechanism) sensitivity. The digital image signal can be stored in the RAM 108 via the bus 114. Various digital image processing includes optical black processing, pixel defect correction processing, aberration correction, peripheral illumination correction, gain processing, white balance processing, RGB interpolation processing, dynamic range expansion processing, color difference signal conversion, offset processing, gamma correction processing, etc. Includes noise reduction processing, contour correction processing, color tone correction processing, light source type determination processing, scaling processing, and the like.

The actuator 117 is a drive device for driving the pan head 230 in the horizontal direction or the vertical direction. The actuator 117 is controlled by the drive control unit 104 via the bus 114. The A / D conversion unit 118 is a device for converting an analog audio signal around the image pickup device 30 acquired by the microphone 240 into a digital audio signal, and the digital audio signal is stored in the RAM 108.

Next, the components of the image pickup apparatus 30 will be described. The image pickup apparatus 30 is configured to include an image pickup unit 200, a drive unit 210, a sensor 220, a pan head 230, and a microphone 240. Further, the image pickup unit 200 is configured to include a zoom lens 201, a focus lens 202, an aperture 203, an infrared cut filter 204, and an image pickup element 205.

The zoom lens 201 can adjust the focal length of the lens in order to adjust the size of the subject, and is moved along the optical axis by the drive unit 210. The focus lens 202 can adjust the focus on the subject and is moved along the optical axis by the drive unit 210. The aperture 203 can adjust the amount of light passing through the lens and is operated by the drive unit 210. The infrared cut filter 204 is a filter (for example, optical glass) that blocks the transmission of incident infrared light, and is operated by the driving unit 210.

The drive unit 210 is a device for driving each component of the image pickup unit 200, and has, for example, a stepping motor or the like. The exciting power for driving the stepping motor is controlled by the drive control unit 104.

For example, when sufficient illuminance can be obtained from the subject in the daytime, the infrared cut filter 204 is inserted closer to the subject than the image pickup device 205. When the infrared cut filter 204 is inserted into the image pickup unit 200, the image pickup device 205 composed of an image sensor or the like receives light that does not contain infrared light. Further, for example, when sufficient illuminance cannot be obtained from the subject at night, the infrared cut filter 204 is removed from the image pickup unit 200. As a result, the image sensor 205 can receive light including infrared light. While the infrared cut filter 204 is removed, the illuminance of the subject may be ensured by irradiating the subject with infrared illumination in order to ensure the visibility of the dark portion of the subject.

The image pickup device 205 is an element that receives reflected light from the subject and generates a subject image, and for example, a CMOS image sensor is used. The image pickup element 205 photoelectrically converts the light incident through the zoom lens 201, the focus lens 202, the aperture 203, and the infrared cut filter 204 to generate an analog image signal. The analog image signal is amplified by sampling processing such as correlated double sampling and transmitted to the A / D conversion unit 116. The measured value of the amplification process is determined by the CPU 100.

The sensor 220 is a measurement unit that measures three-dimensional spatial information, time information, and environmental information of the image pickup apparatus 30, and is composed of, for example, an acceleration sensor, an angular velocity sensor, a geomagnetic sensor, a GPS sensor, an illuminance sensor, and the like. The sensor 220 acquires measured values such as acceleration, angular velocity, orientation, position, and illuminance of the imaging system 10 at a predetermined sampling rate, and transmits various measured values to the CPU 100 via the bus 114.

The pan head 230 is configured to include a pan drive unit and a tilt drive unit so that the image pickup unit 200 can be fixed at an arbitrary position of the user. The pan drive is configured to include a bottom case and a turntable. By rotating the turntable horizontally, the image pickup unit 200 can be panned horizontally in the range of -175 ° to + 175 °. The tilt drive unit is configured to include a support column arranged on the turntable and an image pickup unit 200. The tilt drive unit can tilt the image pickup unit 200 in the vertical direction in the range of 0 ° to 90 °. As a result, the user can shoot in a desired shooting direction by rotating the image pickup unit 200 in the horizontal or vertical direction via the actuator 117. At that time, the drive range of the actuator 117 is controlled by the drive control unit 104.

The microphone 240 is a sound acquisition unit that acquires sound around the image pickup unit 200 and outputs an analog audio signal to the A / D conversion unit 118. The A / D conversion unit 118 converts the analog audio signal into a digital audio signal, and stores the digital audio signal in the RAM 108. The digital voice signal stored in the RAM 108 is subjected to compression processing or voice processing in the voice processing unit 105. The voice processing includes a processing for removing a specific frequency component in the acquired voice and a processing for lowering the volume level.

In the image pickup system 10 of FIG. 1, the case where the image processing device 20 and the image pickup device 30 are integrally configured is shown, but the image processing device 20 and the image pickup device 30 may be configured separately. In that case, the image pickup device 30 is configured to be connected to the image processing device 20 via a network or a cable. When the image pickup system 10 is configured as a separate body, a part of the configuration of the image processing device 20, for example, the A / D conversion unit 116, the A / D conversion unit 118, the image processing unit 115, the actuator 117, and the like are included in the image pickup device 30. It may be provided inside.

The imaging system 10 is mounted at various positions of the vehicle, such as inside or outside the vehicle, in front of, sideways, or behind the vehicle. Examples of vehicles on which the image pickup system 10 is mounted include passenger cars, buses, trucks, trains, and the like. Since the vibration environment of the image pickup system 10 changes depending on the type of vehicle and the position where it is mounted, the drive speed is set according to the type of vehicle and the mounting position, and the stepping motor is driven so as not to step out. do. The speed of the image pickup system 10 is the speed detected by the sensor 220, which corresponds to the speed of the vehicle on which the image pickup system 10 is mounted. The vibration generated in the image pickup system 10 appropriately changes depending on, for example, the mounting position of the image pickup system 10 with respect to the vehicle, the type of the mounted vehicle, the road surface condition, and the like.

Next, with reference to FIG. 2, a process executed by the image pickup system 10 corresponding to the present embodiment will be described. FIG. 2 shows an example of a flowchart of the process executed by the image pickup system 10. In this embodiment, an example of controlling the drive speed of the stepping motor included in the drive unit 210 will be described. The process corresponding to FIG. 2 is realized by the CPU 100 executing a program stored in the ROM 109 or the storage unit 110 and functioning as the detection unit 101, the prediction unit 102, the determination unit 103, and the drive control unit 104. It is assumed that the image is captured by the image pickup apparatus 30 while the process of FIG. 2 is being performed.

In S201, the detection unit 101 controls the sensor 220 to acquire the displacement of the acceleration of the imaging system 10 mounted at a predetermined position in a predetermined vehicle at a predetermined sampling rate. The detection unit 101 acquires the acceleration of the image pickup system 10 acquired by the sensor 220. When the pan head 230 is in operation, the detection unit 101 acquires the acceleration of only the imaging system 10 by excluding the influence of the acceleration generated by the movement of the pan head 230. Further, in the above, the case where the acceleration of the imaging system 10 is acquired by the acceleration sensor has been described, but the acquisition method of the acceleration is not limited to this, and the measured value acquired by the angular velocity sensor, the magnetic sensor, GPS, or the like. You may calculate by combining any one or more of.

In the following S202, the detection unit 101 calculates the speed of the imaging system 10 based on the acceleration acquired in S201. Based on any one or more of the acquired or calculated accelerations, the detection unit 101 can physically and mathematically calculate the speed of the imaging system. Further, the detection unit 101 determines the moving state of the imaging system 10 based on the calculated speed.

Here, with reference to FIG. 3, a method of determining the moving state of the imaging system 10 in the present embodiment will be described. FIG. 3 shows an example of a moving state of the imaging system 10. In FIG. 3, the acceleration 301 of the image pickup system 10 is shown by a solid line, and the speed 302 of the image pickup system 10 is shown by a broken line. In the graph of FIG. 3, the vertical axis shows velocity and acceleration, and the horizontal axis shows time. In FIG. 3, Th1 to Th3 indicate a speed threshold value for determining the moving state of the imaging system 10. Sections 303 to 306 indicate a time division in which the image pickup system 10 is in a moving state. For example, in section 303, the image pickup system 10 is in a stopped state. Further, the section 304 indicates a low-speed traveling state, the section 305 indicates a medium-speed traveling state, and the section 306 indicates a high-speed traveling state.

Hereinafter, the relationship between the speed threshold value of the image pickup system 10 (or the vehicle on which the image pickup system 10 is mounted) and the classification of the moving state will be described.

When the speed 302 is less than the threshold value Th1, the detection unit 101 determines that the image pickup system 10 is in the stopped state 303. Next, the detection unit 101 determines that the image pickup system 10 is in the low-speed traveling state 304 when the speed 302 is equal to or higher than the threshold value Th1 and lower than the threshold value Th2. When the speed 302 is equal to or higher than the threshold value Th2 and less than the threshold value Th3, the detection unit 101 determines that the image pickup system 10 is in the medium speed running state 305. Finally, the detection unit 101 determines that the image pickup system 10 is in the high-speed running state 306 when the speed 302 is the threshold value Th3 or more.

In this way, the detection unit 101 can determine the moving state based on which threshold range the calculated speed of the imaging system 10 belongs to. In the present embodiment, the number of moving state divisions of the imaging system 10 or the speed threshold value for specifying the moving state classification is not limited.

Returning to the description of FIG. 2, in S203, the prediction unit 102 estimates the vibration of the image pickup system 10, and the determination unit 103 determines the driving speed of the stepping motor based on the vibration.

Here, with reference to FIGS. 4 (A) and 4 (B), a table showing the relationship between the vibration of the image pickup system 10 corresponding to the moving state of the image pickup system 10 and the maximum drive speed of the stepping motor will be described. In the present embodiment, the tables of FIGS. 4 (A) and 4 (B) will be described with respect to the case where the image pickup system 10 is mounted in front of or near the rear of a bus (for example, a route bus or a high-speed bus).

The vehicle equipped with the image pickup system 10 is not limited to the bus, and other vehicles such as passenger cars, trucks and trains are not excluded. In this embodiment, a table of vibrations of other vehicles such as passenger cars, trucks and trains is not shown, but a table in which vibrations and the like corresponding to various vehicle types are registered is stored in the ROM 109 or the storage unit 110 in advance. By doing so, it becomes possible to make the drive speed of the stepping motor compatible with various vibration environments.

In the table 400 shown in FIG. 4A and the table 410 shown in FIG. 4B, each value of the vehicle 401, the position 402, the speed 403, the state 404, the predicted maximum vibration value 405, and the maximum drive speed 406 is displayed. It is registered. FIG. 4A shows a table 400 for vibration and the like when the imaging system 10 is mounted in front of the bus, and FIG. 4B shows vibration and the like when the imaging system 10 is mounted in the rear of the bus. Table 410 is shown.

The vehicle 401 indicates the type of vehicle on which the image pickup system 10 is mounted. Although the bus is described in this figure, it may be a vehicle type other than this. The position where the image pickup system 10 is mounted is registered in the position 402, and the speed range of the image pickup system 10 (or the vehicle in which the image pickup system 10 is mounted) is registered in the speed 403. In the state 404, the above-mentioned classification of the moving state corresponding to the speed of the image pickup system 10 is registered. Further, the maximum vibration value generated in the image pickup system 10 in the moving state of the image pickup system 10 is registered in the predicted maximum vibration value 405, and the stepping motor is driven without stepping out at the predicted maximum vibration value at the maximum drive speed 406. The speed that can be registered is registered.

The process in which the determination unit 103 determines the maximum drive speed of the stepping motor will be described with reference to the table 400 of FIG. 4 (A). When the prediction unit 102 determines that the speed of the image pickup system 10 is less than 1 km / h and the state of the image pickup system 10 is stopped, the determination unit 103 determines that the maximum drive speed of the stepping motor corresponding to the stoppage is 1200 PPS. When the speed of the image pickup system 10 is 1 km / h or more and less than 30 km / h and the predictor 102 determines that the state of the image pickup system 10 is in low speed running, the determination unit 103 drives the maximum stepping motor corresponding to the low speed running. The speed is determined to be 1000 PPS. When the speed of the image pickup system 10 is 30 km / h or more and less than 60 km / h and the prediction unit 102 determines that the state of the image pickup system 10 is in medium speed running, the determination unit 103 is a stepping motor corresponding to medium speed running. The maximum drive speed is determined to be 800PPS. When the prediction unit 102 determines that the speed of the image pickup system 10 is 60 km / h or more and the state of the image pickup system 10 is in high-speed running, the determination unit 103 determines that the maximum drive speed of the stepping motor corresponding to high-speed running is 600 PPS. do. Next, a process in which the determination unit 103 determines the maximum drive speed of the stepping motor will be described with reference to the table 410 in FIG. 4 (B). Since the items in the table 410 in FIG. 4B are the same as those in FIG. 4A, the same reference numbers are given and the description of each item is omitted.

When the prediction unit 102 determines that the speed of the image pickup system 10 is less than 1 km / h and the state of the image pickup system 10 is stopped, the determination unit 103 determines that the maximum drive speed of the stepping motor corresponding to the stoppage is 1100PPS. When the speed of the image pickup system 10 is 1 km / h or more and less than 30 km / h and the predictor 102 determines that the state of the image pickup system 10 is in low speed running, the determination unit 103 drives the maximum stepping motor corresponding to the low speed running. The speed is determined to be 900PPS. Since the maximum drive speed of the stepping motor corresponding to the medium-speed running and high-speed running states in FIG. 4B is the same as the data in FIG. 4A, the description thereof will be omitted.

Here, the predicted maximum vibration value in the stopped and low-speed running state of FIG. 4 (B) is higher than the predicted maximum vibration value in the stopped and low-speed running state of FIG. 4 (A). Generally, the engine of the bus is mounted at the rear of the bus to prevent the exhaust heat of the engine from entering the vehicle. Therefore, since the engine vibration of the bus is transmitted to the image pickup system 10, the predicted maximum vibration value of the image pickup system 10 in the stopped and low-speed running state of FIG. 4 (B) is larger than the predicted maximum vibration value of FIG. 4 (A). It is rising.

However, the prediction of the vibration of the imaging system 10 in the present embodiment is not determined only by referring to the table of vibration and the like, but may be performed by mathematical approximation calculation such as a spline function or interpolation processing. .. For example, when considering the type of vehicle on which the image pickup system 10 is mounted, the mounting position of the image pickup system 10 on the vehicle, and the condition of the road surface (for example, rough terrain with poor pavement), the acceleration, angular velocity, and orientation acquired by the sensor 220 are taken into consideration. The prediction unit 102 can calculate the predicted maximum vibration value of the imaging system 10 based on the measured values such as the position and the position.

Further, the determination unit 103 compares the predicted maximum vibration value of FIG. 4A or FIG. 4B with the calculated predicted maximum vibration value, corrects the maximum driving speed of the stepping motor, and drives the driving speed. Can be determined. When the calculated predicted maximum vibration value is smaller than the predicted maximum vibration value shown in FIG. 4 (A) or FIG. 4 (B), the determination unit 103 corrects so that the drive speed becomes high within the range where the stepping motor does not step out. can do. On the other hand, when the calculated predicted maximum vibration value is larger than the predicted maximum vibration value shown in FIG. 4 (A) or FIG. Can be modified to.

For example, when the image pickup system 10 as shown in FIG. 4A is mounted in front of the bus and the moving state of the image pickup system 10 is low speed traveling, the prediction unit 102 is based on various measured values acquired by the sensor 220. Calculates the predicted maximum vibration value of the imaging system 10. When the calculated predicted maximum vibration value is, for example, 30 G, the determination unit 103 can correct the maximum drive speed of the stepping motor in low-speed running from 1000 PPS to 1200 PPS. The correction of the maximum drive speed of the stepping motor may be interpolated by a linear approximation or a non-linear approximation. The above shows, as an example, the case where the calculated maximum predicted vibration value is smaller than the predicted maximum vibration value shown in FIG. 4 (A). On the other hand, when the calculated predicted maximum vibration value is larger than the predicted maximum vibration value shown in FIG. 4A, the determination unit 103 corrects the driving speed of the stepping motor to be slower.

The correction of the maximum drive speed of the stepping motor when the image pickup system 10 as shown in FIG. 4B is mounted behind the bus is the same as the correction when the image pickup system 10 is mounted in front of the bus. It is done by the method of.

Further, the determination of the drive speed of the stepping motor in the present embodiment is not limited to the value of the maximum drive speed 406 of the table shown in FIGS. 4 (A) and 4 (B), and the speed 403 and the predicted maximum vibration are not limited. Based on the actual value of the value 405, the drive speed of the stepping motor may be calculated as a value smaller than the maximum drive speed 406 by the interpolation process. For example, the interpolation process may be performed by interpolation processing based on a linear approximation or a non-linear approximation between the maximum drive speeds shown in the table of FIG. 4A or FIG. 4B. This process makes it possible for the determination unit 103 to select a drive speed that does not cause stepping-out of the stepping motor.

Returning to the description of FIG. 2, in S204, the determination unit 103 determines the exciting power for driving the stepping motor based on the drive speed of the stepping motor determined in S203.

In S205, for example, based on the illuminance of the subject measured by the sensor 220 and the environmental information, the detection unit 101 determines whether the illuminance or the like is lower than a predetermined level and whether the infrared cut filter 204 is inserted. The drive control unit 104 determines whether or not to drive the stepping motor of the infrared cut filter 204 according to the determination result. Alternatively, the detection unit 101 may measure the illuminance of the subject based on the luminance value of the specific pixel in the captured image, and determine whether or not to drive the subject based on the measurement result. For example, when a subject that is always included in the captured image is present, the illuminance may be measured based on the luminance value of the pixel corresponding to the position of the subject. Further, when measuring the illuminance, a threshold value according to the measurement method is used. (I) For example, when the illuminance detected at night is less than the threshold value and the infrared cut filter 204 is in the inserted state (YES in S205), the process shifts to S206 and the infrared cut filter 204 is removed. Further, (ii) for example, even when the illuminance detected in the daytime is equal to or higher than the threshold value and the infrared cut filter 204 is not inserted (YES in S205), the processing shifts to S206 and the infrared cut filter 204 To insert. If the above (i) or (ii) does not apply (NO in S205), the process shifts to S207, and the infrared cut filter 204 is not inserted or removed. Since the threshold value of the subject illuminance changes according to the performance of the image sensor 205 and the like, the number and numerical values of the threshold value of the subject illuminance in the present embodiment are not limited.

In the above, the driving of the stepping motor in the case of driving the infrared cut filter 204 among the constituent elements of the image pickup apparatus 30 has been described. On the other hand, the stepping motor is also used when driving other components of the image pickup device 30 of the zoom lens 201, the focus lens 202, the aperture 203, and the pan head 230, and the drive of these stepping motors is the surroundings. It does not depend on the illuminance environment of. Rather, the drive of these stepping motors is executed based on the user's operation input via the input unit 106 (for example, an input of whether or not to drive a drive target such as a zoom operation), and therefore the user. The drive control unit 104 can determine whether or not the stepping motor is driven based on whether or not a predetermined input operation is received from the above. If there is a predetermined operation input from the user, the process proceeds to S206 (YES in S205). If there is no user setting information, the process returns to S201 (NO in S205).

In S206, the drive control unit 104 gives an input pulse related to the drive speed to the drive unit 210 via the bus 114 in order to drive the stepping motor based on the exciting power determined in S204. Based on the input pulse related to the drive speed, the drive unit 210 drives the stepping motor, and then the process returns to S201.

However, the drive target in the present embodiment is not limited to the infrared cut filter 204, but all controlled by using the stepping motor. For example, control targets include a zoom lens 201, a focus lens 202, a diaphragm 203, a pan head 230, and the like, and when driving these, the exciting power of the stepping motor is determined and driven in the same manner.

In this embodiment, for the image pickup system 10 (or the vehicle on which the image pickup system 10 is mounted), the drive speed of the stepping motor can be determined according to the moving speed and the estimated magnitude of vibration. The drive speed may be the value registered in the table as it is, or the drive calculated by interpolation according to the maximum drive speed of the stepping motor registered in the table and the moving speed or the estimated vibration value. Velocity may be used. As a result, the stepping motor can be controlled at an appropriate drive speed in a vibration environment, so that the stepping motor can be prevented from stepping out.

[Embodiment 2]
Next, the second embodiment will be described. In this embodiment, a method of suppressing or removing the driving sound of the stepping motor that affects the recorded sound at the time of shooting will be described. The system configuration corresponding to this embodiment is as shown in FIG. Further, the method of determining the moving state of the imaging system 10 is according to FIG. 3, and the relationship between the moving state of the imaging system 10 and the maximum drive speed of the stepping motor is also as shown in FIG. Omit.

The process executed by the image pickup system 10 corresponding to the present embodiment will be described with reference to FIG. FIG. 5 shows a flowchart of an example of the processing of the present embodiment executed by the imaging system 10. The process corresponding to the flowchart is realized by the CPU 100 executing a program stored in the ROM 109 or the storage unit 110. However, in FIG. 5, the processes from S201 to S205 are the same as the processes described in FIG. 2 of the first embodiment, and thus the description thereof will be omitted here. Further, it is assumed that the image pickup device 30 is performing image capture and voice recording while the process of FIG. 5 is being performed.

In S205, it is determined whether or not the stepping motor is driven, and if it is determined that the stepping motor is driven, the process proceeds to S506. The voice acquisition function is controlled in S506.

The control of the voice acquisition function is a process of limiting voice acquisition during the driving period of the stepping motor, and may include, for example, "input stop", "band limitation", "recording level adjustment", and the like. Hereinafter, specific examples of each process will be described.

First, "stop input" will be described. To stop the voice input, there is a process of stopping the operation of the microphone 240 to stop the voice acquisition operation, or a process of continuing the voice acquisition by the microphone 240 but not recording the voice. When voice recording is not performed, for example, there is a method of muting the voice output in the A / D conversion unit 118. Alternatively, the voice processing unit 105 may mute the voice during the stop period (reduce the sound pressure level to 0). The period for stopping the voice input (stop period) is set to include a section from the start of driving of the actuator to the end of driving. The stop period may be determined according to the drive speed of the actuator determined in S203 of the previous stage. In that case, the information on the stop period may be registered in the table 400 or the table 410 in association with the maximum drive speed 406. Further, the length of the stop period may be modified by interpolation according to the magnitude of the drive speed. Further, the user may preset it.

In S506, the drive control unit 104 transmits a voice input stop command to the microphone 240, stops the operation of the microphone, sets a timer based on the above stop period, and starts measuring the elapsed time. After that, the process proceeds to S206, and the drive control unit 104 drives the stepping motor based on the drive speed determined in S203. When the driving of the stepping motor in S206 is completed, the process proceeds to S508. In S508, when the elapsed time reaches the above stop period and the timer expires, the drive control unit 104 transmits a voice input restart command to the microphone 240 in S508, and restarts the operation of the microphone. After that, the process shifts to S201.

Next, "bandwidth limitation" will be described. In the present embodiment, when the natural frequency of the image pickup system 10 and the natural frequency generated when the stepping motor is driven match, resonance occurs in the image pickup system 10. The sound generated at the time of resonance is recorded as noise in the recorded voice of the image pickup system 10 at the time of shooting as it is. Therefore, the audio processing unit 105 performs band limiting processing for limiting the audio signal in a predetermined band corresponding to the resonance frequency at the time of resonance of the imaging system 10 from the input audio signal of the microphone 240, and noise is included in the recorded audio. Avoid it.

Here, the frequency characteristics at the time of resonance of the image pickup system 10 will be described with reference to FIGS. 6 (A) to 6 (C). In FIG. 6A, the solid line shows the frequency characteristics when the drive speed of the stepping motor is 400 PPS, and the broken line shows the frequency characteristics when the drive speed of the stepping motor is 600 PPS. Further, the vertical axis of FIG. 6A shows the sound pressure level, the horizontal axis shows the frequency, and 600 to 605 show the resonance position. When the drive speed of the stepping motor is 600PPS or more, the frequency characteristics are the same as those in the case of 600PPS, so the description thereof will be omitted. The resonance position (600 to 605), which is the position of the peak of the waveform drawn by the solid line or the broken line in FIG. 6A, corresponds to the resonance frequency, and since the sound pressure level is high, it is a human noise. Perceived by the ear. In the table 610 shown in FIG. 6B and the table 620 shown in FIG. 6C, the drive speeds 611 and 621 of the stepping motor and the resonance positions 612 and 622 corresponding to 600 to 605 in FIG. 6A are shown. , Resonance frequencies 613 and 623 at the resonance position are shown.

In FIG. 6B, there are three resonance positions 612, and the resonance frequencies 613 are 1.31 kHz, 1.75 kHz, and 2.37 kHz, respectively. In FIG. 6C, there are four resonance positions 622, and the resonance frequencies 623 are 1.31 kHz, 1.75 kHz, 2.36 kHz, and 2.53 kHz, respectively.

The frequency characteristics shown in FIGS. 6 (A) to 6 (C) are merely examples, and the resonance frequency varies depending on factors such as the natural frequency of the image pickup system 10 and the natural frequency of the stepping motor. Therefore, the number of resonance frequencies and resonance frequencies that cause noise in this embodiment are not limited to the above examples.

The voice processing unit 105 can set an attenuation band that covers the entire band (for example, a range of 1 kHz to 3 kHz) in which the resonance frequency shown in FIG. 6A appears. This is an example of the attenuation band setting, and the attenuation band is not limited to this, and the attenuation band is set to a part of the entire resonance frequency band, for example, around 1.3 kHz, which has a particularly high sound pressure level, and 2.4. It may be set in the vicinity of 2.5 kHz. Further, the attenuation band may be set in a range where the sound pressure level is higher than the sound pressure threshold value.

The voice processing unit 105 can realize the band limitation by setting the band limitation filter corresponding to the attenuation band and applying it to the input voice of the microphone 240. The setting of the band limitation of the voice input to the microphone 240 is carried out by one or more methods of automatic setting by the voice processing unit 105, manual setting by the user or another user, or remote setting. An example of the band-limited filter in the present embodiment is a band-pass filter, but the present invention is not limited to the band-pass filter, and any one or more of the low-pass filter, the high-pass filter, and the band elimination filter, or a combination thereof. May be good.

In S506, when the voice processing unit 105 applies the band limiting filter to the voice input via the A / D conversion unit 118 to reduce the noise, the drive control unit 104 sets a timer based on the stop period. Set and measure the elapsed time. After that, the process proceeds to S206, and the drive control unit 104 drives the stepping motor based on the drive speed determined in S203. When the driving of the stepping motor in S206 is completed, the process proceeds to S508. In S508, when the elapsed time reaches the above-mentioned stop period, the voice processing unit 105 cancels the band limiting filter for the voice input via the A / D conversion unit 118. After that, the process shifts to S201.

Next, "adjustment of the recording level" will be described. The recording level can be adjusted by the A / D conversion unit 118 or the voice processing unit 105. In the case of the recording level, the control is performed so as to lower the level uniformly for all bands, instead of adjusting the level only to a specific band. If the recording level is lowered to 0 level, the recording will be stopped and the same as the above input stop. Therefore, here, the recording level is higher than 0 level but lower than the normal recording level. It shall be lowered. The predetermined recording level can be set arbitrarily, but it may be any level as long as it can be determined that the influence of noise is suppressed in the recorded voice.

In S506, when the volume level of the input voice by the A / D conversion unit 118 or the voice processing unit 105 is lowered from the normal recording level to a predetermined level, the drive control unit 104 uses the timer based on the above stop period. And measure the elapsed time. After that, the process proceeds to S206, and the drive control unit 104 drives the stepping motor based on the drive speed determined in S203. When the driving of the stepping motor in S206 is completed, the process proceeds to S508. In S508, the A / D conversion unit 118 or the voice processing unit 105 returns the level of the input voice to the original level according to the elapsed time reaching the above-mentioned stop period. After that, the process shifts to S201.

In the above, in S508, the restriction of the voice acquisition function is released according to the elapsed time reaching the stop period, but the restriction may be forcibly released based on an instruction from the user or the like.

In the present embodiment, the driving sound of the stepping motor that affects the sound of the imaging system can be suppressed or eliminated by controlling the sound acquisition function. As a result, the present embodiment can maintain the quality of the delivered audio at the time of shooting in a good state.

As another embodiment, the present invention supplies a program that realizes one or more functions of the above-described embodiment to a system or device via a network or storage medium, and the system or device is one or more in a computer. It can also be realized by the process of reading and executing the program by the processor. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

The invention is not limited to the above embodiment, and various modifications and modifications can be made without departing from the spirit and scope of the invention. Therefore, a claim is attached to publicize the scope of the invention.

10: Image pickup system, 20: Image processing device, 30: Image pickup device

Claims (16)

An image pickup unit that captures an image of the subject,
A drive unit that drives the components of the image pickup unit,
A predictive means for predicting vibration of the image pickup unit and
A determining means for determining the driving conditions for driving the driving unit based on the predicted vibration, and
An imaging system including a drive control means for driving the drive unit according to the determined drive conditions. The imaging system according to claim 1, wherein the drive unit includes a stepping motor, and the drive condition is a drive speed for driving the stepping motor. Further, a storage unit for storing a table for registering the vibration of the imaging unit and the driving condition in association with each other is provided.
The imaging system according to claim 1 or 2, wherein the determining means determines the driving conditions with reference to the table based on the predicted vibration. The imaging system according to claim 3, wherein the determination means determines the drive condition by interpolation based on the predicted vibration and the drive condition registered in the table. Further provided with a detection means for detecting the moving speed of the image pickup unit,
In the table, the moving speed of the image pickup unit is further registered in association with the vibration of the image pickup unit.
The imaging system according to claim 3, wherein the predicting means predicts the vibration with reference to the table based on the moving speed detected by the detecting means. The storage unit stores a table for each type of vehicle on which the imaging system is mounted, and stores the table.
The vibration associated with the moving speed differs from table to table.
The imaging system according to claim 5, wherein the determining means and the predicting means refer to a table according to the type of vehicle on which the imaging system is mounted. The storage unit further stores the table for each mounting position of the imaging system in the type of vehicle on which the imaging system is mounted.
The imaging system according to claim 6, wherein the determination means and the prediction means further refer to a table according to the mounting position. The image pickup unit further includes an acceleration sensor.
The imaging system according to any one of claims 1 to 4, wherein the predicting means predicts the vibration of the imaging unit based on the measured value of the acceleration sensor. The components include an infrared cut filter.
A measuring means for measuring the illuminance of a subject imaged by the imaging unit,
A determination means for determining whether or not to perform the imaging by inserting or removing the infrared cut filter according to the illuminance of the subject.
Equipped with
The drive control means according to any one of claims 1 to 7, wherein the drive control means drives the drive unit so as to insert or remove the infrared cut filter according to the determination result of the determination means. Imaging system. The components include at least one of a zoom lens, a focus lens, an aperture, and a pan head.
Further provided with an input means for receiving an operation input instructing the drive of at least one of the zoom lens, the focus lens, the diaphragm, and the pan head.
The imaging system according to any one of claims 1 to 7, wherein when the operation input is received by the input means, the driving unit is driven so as to drive the component that has received the operation input. The image pickup unit further includes audio acquisition means.
The imaging system according to any one of claims 1 to 10, wherein the voice acquisition means stops operating while the driving unit is being driven. The image pickup unit is further provided with audio acquisition means, and the image pickup unit is further provided with audio acquisition means.
Further provided with a processing means for processing the voice acquired by the voice acquisition means,
While the drive unit is being driven, the processing means processes the audio signal output from the audio acquisition means to reduce the level of noise generated from the drive unit included in the audio signal. The imaging system according to any one of claims 1 to 10. The imaging system according to claim 12, wherein the processing means reduces the level of a predetermined band corresponding to the noise in the audio signal. The imaging system according to claim 12, wherein the processing means reduces the level of the entire band in the audio signal. It is a control method of an image pickup system including an image pickup unit that captures an image of a subject and a drive unit that drives a component of the image pickup unit.
The prediction means is a prediction process for predicting the vibration of the image pickup unit, and
A determination step in which the determination means determines the drive conditions for driving the drive unit based on the predicted vibration.
A control method for an imaging system, comprising a drive control step in which the drive control means drives the drive unit according to the determined drive conditions. A program for making a computer function as each means of the imaging system according to any one of claims 1 to 14.

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