JP2014239554A - Detection system, signal processing method thereof, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a detection system capable of performing accurate and high-precision detection by making an accurate determination in accordance with peculiar condition setting adaptive to an environment or a place within a detection range, a signal processing method thereof and a program.SOLUTION: The detection system comprises: a state storage section 18 for storing information each having various attribute information in a state of a detection range and including a state change of the attribute; a determination section 16 for performing detection determination processing with an attribute value suitable for an attribute at a position within the detection range by acquiring and referencing the attribute information stored in the state storage section 18; and an object position determination section 17 which searches for a position and a size of an object in all images from detection information obtained by the determination section 16, determines the position of the object including the detection range and is capable of storing detection information including the detection range relating to the object in a position storage section 144. The determination section 16 acquires a response speed value positioned within a predetermined range for a number of a light source and an image included in the attribute information, determines a detection time from the detection response speed value at the acquired position and performs the detection determination processing at a response speed suitable for the position.

Description

  The present invention relates to a detection system that detects the state of a subject using an imaging device or the like, a signal processing method thereof, and a program, for example.

For example, an imaging apparatus used in a nighttime crime prevention system shown in Patent Document 1 has been proposed.
This imaging apparatus has a signal processing unit, and the light source has a frequency higher than 100 Hz or 120 Hz (when a commercial power source of 50 Hz or 60 Hz is used as the power source, the brightness of the light source fluctuates at 100 Hz or 120 Hz that is twice that). Modulate with high frequency. Further, the signal processing unit has a detection unit for detecting the high frequency modulation signal.
However, this imaging apparatus needs to have a frame rate higher than its modulation frequency.

By the way, a standard called NTSC (National Television Standards Committee) system or PAL (Phase Alternating Line) system is adopted for imaging apparatuses which are widely spread in general.
Since an image pickup apparatus adopting such a standard has a low frame rate, for example, it cannot be used as an image pickup apparatus for a crime prevention system as shown in Patent Document 1.

Therefore, a detection system that can detect a light source or the state of a subject irradiated with the light source and can be applied to a crime prevention system adopting a standard such as NTSC has been proposed (see Patent Document 2).
This detection system detects the state of the subject of the frequency component of the light source.

Japanese Patent No. 3019309 JP 2008-141251 A

However, the detection system described above is a detection system that acquires and browses the detection state using a common parameter in the state of each moving object detection range of a plurality of light sources, and is unique to each environment and location of each moving object detection range. It was difficult to accurately determine the conditions.
For example, when the point A is used for vehicle detection in an outdoor environment and the point B is used for human detection in an indoor environment, there are differences in the subject sensitivity and response speed detection parameters in the moving object detection range. May be difficult.
Further, in one moving object detection range, it may be difficult to specify moving objects, and determination including unnecessary objects may be made.

  In addition to being able to detect the state of the light source or the subject irradiated with the light source, the present invention enables accurate determination with unique condition settings adapted to the environment and location of the moving object detection range, and enables accurate and highly accurate detection. And a signal processing method and program thereof.

  A detection system according to a first aspect of the present invention performs at least one light source, at least one imaging device that images the light source or a subject irradiated with the light source, and an analysis process on a signal acquired from the imaging device. An analysis processing unit; a determination unit that detects and determines the state of the light source or the subject based on an analysis result of the analysis processing unit; and a position storage unit that can store information about positions including detection ranges in images of a plurality of subjects. A state storage unit that stores various types of attribute information at least in the state of the detection range, stores information including a change in the state of the attribute, and the position of the subject in all images from the detection information obtained by the determination unit. Search the size to determine the position of the subject including the detection range, acquire detection information including the detection range related to the subject, and detect the detection information. A subject position determination unit that can be stored in the position storage unit as information relating to the position, and the analysis processing unit acquires the signal from the imaging device every predetermined scanning plane period, and a plurality of different scanning planes The time average of the signal level difference is obtained from the signal level difference between the signals, and an analysis process is performed to perform a predetermined calculation based on the value of the time average, and the calculation result of the analysis process is sent to the determination unit. And when the detection information is stored in the position storage unit, the analysis processing is selectively performed on the image in the detection position range specified in the detection information. The attribute information stored in the storage unit is acquired and referenced, and detection determination processing is performed with an attribute value suitable for the attribute at the position of the detection range.

  A signal processing method of a detection system according to a second aspect of the present invention includes an imaging step of imaging at least one light source or an object irradiated by the light source with at least one imaging device, and every predetermined scanning plane period from the imaging device. An analysis process for acquiring a signal, calculating a time average of the signal level difference from the signal level difference of the signal between a plurality of different scanning planes, and further performing an analysis process for performing a predetermined calculation based on the value of the time average A step, a determination step of detecting and determining the state of the light source or subject based on the analysis result of the analysis processing step, and information including various attribute information at least in the state of the detection range and including a change in the state of the attribute From the state storage step stored in the state storage unit and the detection information obtained in the determination step, the position of the subject in all images A subject position determining step of searching for a size to determine a position of a subject including a detection range, obtaining detection information including a detection range regarding the subject, and storing the detection information in the position storage unit as information about the position; In the analysis processing step, when the detection information is stored in the position storage unit, the analysis processing is selectively performed on an image in the detection position range specified in the detection information. Including a step, wherein the determination step includes a step of obtaining and referring to the attribute information stored in the state storage unit and performing detection determination processing with an attribute value suitable for the attribute at the position of the detection range.

  According to a third aspect of the present invention, there is provided an imaging process in which at least one light source or a subject irradiated with the light source is imaged by at least one imaging device, a signal is acquired from the imaging device every predetermined scanning plane period, and a plurality of An analysis process for obtaining a time average of the signal level difference from the signal level difference of the signal between different scanning planes, further performing an analysis process for performing a predetermined calculation based on the value of the time average, and an analysis of the analysis process A determination process for detecting and determining the state of the light source or subject according to the result, and a state storage process for storing various attribute information at least in the state of the detection range and storing information including a state change of the attribute in the state storage unit Then, from the detection information obtained in the determination process, the position and size of the subject in all the images are searched to determine the position of the subject including the detection range, and the subject A subject position determination process for acquiring detection information including a detection range relating to the position and storing the detection information in the position storage unit as information on the position. In the analysis process, the detection information is stored in the position storage unit. Is stored in the state storage unit in the determination process, including a process of selectively performing the analysis process on the image in the detection position range specified in the detection information. This is a program that causes a computer to execute signal processing of a detection system including processing for acquiring and referring to attribute information and performing detection determination processing with an attribute value suitable for the attribute in the position of the detection range.

  According to the present invention, not only can the state of the light source or the subject irradiated with the light source be detected, but also accurate determination can be made by setting specific conditions adapted to the environment and location of the moving object detection range, and the accurate and high accuracy Detection can be realized.

It is a figure which shows the structural example of the detection system which concerns on embodiment of this invention. It is a figure which shows an example of the information table preserve | saved in the position memory | storage part which concerns on this embodiment. It is a figure which shows notionally the state before the position determination of the to-be-photographed object in the to-be-photographed object position determination part which concerns on this embodiment, and the state after position determination. It is a figure which shows an example of the (x, y) width table information of the detection range referred in order to perform position determination in the to-be-photographed object position determination part which concerns on this embodiment. It is a figure which shows an example of the detection information stored in the position search information storage part which concerns on this embodiment. It is a figure which shows an example of the attribute descriptor stored in the to-be-photographed object state memory | storage part which concerns on this embodiment. It is a figure which shows an example of the group descriptor stored in the to-be-photographed object state memory | storage part which concerns on this embodiment. It is a figure which shows an example of the group connection descriptor stored in the to-be-photographed object state memory | storage part which concerns on this embodiment. The detection range after position determination when detected by one imaging device (camera) is shown. The detection range after position determination when a four-screen dividing device is used with four imaging devices (cameras) is shown. It is a figure which shows the example of a group setting in the case of dividing into two groups each containing a some detection range, and performing a re-determination in a group unit. It is a figure which shows the example of a group setting in the case of dividing into three groups each including 1 or a plurality of detection ranges, and performing redetermination in a group unit. It is a flowchart for demonstrating concretely the basic detection position determination process in the subject position determination unit according to the present embodiment, and is a diagram illustrating a process when the position determination process is performed. It is a flowchart for demonstrating specifically the detection position determination process in the to-be-photographed object position determination part which concerns on this embodiment, Comprising: It is a figure which shows a process when not performing a position determination process. It is a figure for demonstrating the search method of the object of one light source or reflected light. It is a figure for demonstrating the fine adjustment process of a detection range. It is a flowchart for demonstrating the operation | movement outline | summary of the detection system which concerns on this embodiment centering on a to-be-photographed object position determination process. It is a flowchart for demonstrating the operation | movement outline | summary of the detection system which concerns on this embodiment centering on a to-be-photographed object position determination process. It is a flowchart which shows the process which acquires the detection sensitivity value of FIG. 17, and determines a detection sensitivity. It is a flowchart which shows the process which acquires the response speed value of FIG. 17, and sets a response speed value to a threshold value. It is a flowchart which shows the process which acquires the failure state of FIG. 17, and determines a failure state. It is a flowchart which shows the process which acquires the other status of FIG. 17, and determines another status state. It is a flowchart which shows the process which acquires the group number information of FIG. 17, and determines the state according to group. It is a flowchart which shows the process which acquires the connection object of the group of FIG. 17, and detects with the connection state of a group. It is a figure which shows an example for demonstrating the structure of CCD which concerns on this embodiment. It is a figure for demonstrating the time series of CCD of FIG. It is a figure which shows the example of an arrangement | sequence of the pixel of a single plate complementary color filter type CCD. It is a figure which shows an example of the combination of the color signal in odd field OFD and even field EFD. It is a timing chart for demonstrating the signal processing method of the luminance signal of the light source analysis process part which concerns on this embodiment. It is a figure which shows the waveform W6 about the frequency component contained in the light source. It is a figure which shows an example of the relationship between duty ratio D and square sum SACBD.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[First Embodiment]
FIG. 1 is a diagram illustrating a configuration example of a detection system according to an embodiment of the present invention.

The detection system 10 includes a light source 11 (−1 to −n), an imaging device 12 (−1 to −n), a luminance signal extraction unit 13, a light source analysis processing unit 14, a filter processing unit 15, a determination unit 16, and a subject position. A determination unit 17, a subject state storage unit 18, a group association determination unit 19, and a multi-screen input division device 20 are included. Note that n is 4 in the example of FIG.
The light source analysis processing unit 14 includes a first calculation unit (A) 141, a second calculation unit (B) 142, a calculation processing unit (time average square sum calculation processing unit) 143, and a position storage unit 144.
The subject position determination unit 17 includes a position search processing unit 171 and a position search information storage unit 172.
The subject state storage unit 18 includes an attribute descriptor Patt [pt], a group-specific descriptor Grp [pt], and a group connection descriptor GrpCON [g no] is stored as a table, for example.

The detection system 10 is a system that can detect the state of a light source or a subject irradiated with the light source.
The detection system 10 removes unnecessary moving objects from the signal components of the light source, detects the positions and sizes of a plurality of subjects with high accuracy, and sets each range of the subject positions to the same imaging device (camera) or a plurality of subjects. It is possible to detect a moving object in each range by monitoring with an imaging device (camera).
Furthermore, this detection system 10 has various attribute information in the state of each moving object detection range, and has a storage unit (memory) that stores the state change of the attribute, and acquires and references the state change state ( Browsing).
In the various attribute information, response speed, subject sensitivity, light source failure state, other status, determination result, and the like can be stored in the subject state storage unit.
In addition, each detection range can be associated as an arbitrary group, the grouped state can be stored in the subject state storage unit, parameters for specifying a result determination condition in units of the group are stored, state determination in units of groups, Changes can be acquired and referenced (viewed).
In addition, it is possible to obtain and output the operation determination result by logical operation by logical sum, logical product, or comparison operation as =,>, <, ≠, or independently as a parameter for grouping and determining the result. .
Further, the detection system 10 has a function of displaying the status of each grouping information and attribute information.

  The light sources 11-1 to 11-4 illuminate the subject with a predetermined luminance. The luminance of the light source 11 is variable, and the luminance within the charge accumulation time of the imaging element included in the imaging device 12 changes at a period 4n times the field period of the imaging devices 12-1 to 12-4. Here, n = 1, 2, 3,.

The imaging devices 12-1 to 12-4 used in the detection system 10 according to the present embodiment employ imaging devices having the following specifications.
As an example of the image pickup elements constituting the image pickup apparatuses 12-1 to 12-4, a single plate complementary color filter and a field accumulation type interline transfer CCD (Charge Coupled Device) image sensor (hereinafter simply referred to as a CCD) are used.
As an example, the television system of the imaging devices 12-1 to 12-4 employs the NTSC system, the scanning system employs interlace, the scanning frequency is 15.734 KHz, and the vertical frequency is 59.94 Hz.
The imaging devices 12-1 to 12-4 having such a configuration images the subject illuminated by the light sources 11-1 to 11-4 and outputs a signal obtained by the imaging to the luminance signal extraction unit 13.
Although a CCD image sensor is illustrated here, a CMOS image sensor can also be applied.

Images from the light source 11-1 are acquired by the imaging devices 12-1 to 12-4, and a luminance signal is extracted by the luminance signal extraction unit 13.
When there are a plurality of imaging devices 12-1 to 12-4, the multi-screen input division device 20 converts the image signals into one video signal, and the luminance signal extraction unit 13 extracts the luminance signal.

The luminance signal extraction unit 13 extracts a luminance signal from the input signal and outputs the luminance signal to the first calculation unit 141 and the second calculation unit 142 of the light source analysis processing unit 14.
The luminance signal extracted by the luminance signal extraction unit 13 is adjusted to a signal level optimized for calculation.
The signal level needs to be a signal level that does not overflow in the output values of the first calculation unit 141, the second calculation unit 142, and the calculation processing unit 143. Therefore, the luminance signal extraction unit 13 includes a circuit that adjusts the luminance signal level.
The adjustment value of the luminance signal level may have a table capable of mode switching when there are several modes. The mode may be a video signal standard such as NTSC or PAL, or a frequency mode of the imaging apparatus.

In the light source analysis processing unit 14, the first calculation unit 141 obtains the time average of the level difference of the luminance signal in the m-th and (m + 2) -th fields in the same area of the imaging device.
The output result A of the first calculation unit 141 is output to the calculation processing unit 143.
The second calculation unit 142 obtains a time average of the level difference of the luminance signal in the (m + 1) th and (m + 3) th fields in the same region of the input luminance signal.
The output result B of the second calculation unit 142 is output to the calculation processing unit 143.
The details of the operations of the first calculation unit 141 and the second calculation unit 142 will be described later.
The first calculation unit 141 and the second calculation unit 142 perform calculation processing in accordance with calculation range designation information for analyzing the image stored in the position storage unit 144.

The output result A output from the first calculation unit 141 and the output result B output from the second calculation unit 142 are input to the calculation processing unit 143.
The arithmetic processing unit 143 obtains a square sum value (A ² + B ² ) of the output result and outputs it to the filter processing unit 15.
The arithmetic processing unit 143 performs arithmetic processing according to the calculation range designation information for analyzing the image stored in the position storage unit 144.

The position storage unit 144 stores, for example, detection information on the positions and sizes of a plurality of subjects detected with high accuracy by removing unnecessary moving objects from the signal component of the light source, which is determined by the subject position determination unit 17.
As described above, the light source analysis processing unit 14 includes the position storage unit 144 that can specify a calculation range for image analysis of the first calculation unit 141 and the second calculation unit 142.
The position storage unit 144 can store a plurality (n) pieces of position information.
Therefore, the detection processing of the light source analysis processing unit 14 is performed in the detection of the light source or the subject irradiated with the light source, n in the range of the image specified by the position storage unit 144 (for example, the range Mn = [x1, y1-x2, y2]). One piece of analysis processing is performed within one frame.
Alternatively, if n analysis processes cannot be performed within the time of one frame, the analysis process in one frame is performed in one n range, and after the completion, the analysis in the second range from the next frame is performed. A method of performing processing in order may also be used.
An image in the n designated ranges obtained by the analysis process can be acquired as a detected image if there is a light source or a subject irradiated with the light source.
Since the detection range is not specified in the initial state in which position information or the like is not stored in the position storage unit 144, the light source analysis processing unit 14 performs light source analysis processing on the entire image instead of selective detection processing.

Further, when the position storage unit 144 is a nonvolatile memory or a setting file, the detection position can be restored without being affected by a power failure. In addition, it has a flag for selecting whether or not to determine the subject position.
A part of the position storage unit 144 has a volatile memory and can be used for temporary storage.
The position storage unit 144 has a function of saving information such as the position coordinates and size of the subject, the frequency detection sensitivity (signal level) of the subject, the subject individual number, and the like.

  FIG. 2 is a diagram illustrating an example of an information table stored in the position storage unit 144 according to the present embodiment.

In FIG. 2, “No” indicates the individual number of the subject. “X, y” indicates the start position coordinates of the subject, and “xe, ye” indicates the end position coordinates of the subject. “N” indicates a number corresponding to the number of subjects. “Level” indicates a signal level (signal intensity) which is frequency sensitivity of the subject.
In this example of the table TBL1, the subject of “No. 1” is the first subject with the start position coordinates “10, 10” and the end position coordinates “20, 20”, and the signal level is relatively high. “40”.
The subject of “No. 2” is the second subject whose start position coordinates are “30, 30” and end position coordinates are “50, 60”, and its signal level is relatively “43”.
The “No. 3” subject is the third subject whose start position coordinates are “100, 100” and end position coordinates are “120, 120”, and its signal level is relatively “50”.
The subject of “No. 4” is the fourth subject having a start position coordinate of “300, 300” and an end position coordinate of “325, 315”, and its signal level is relatively “60”.

As described above, the light source analysis processing unit 14 of the present embodiment includes the position storage unit 144 that is a memory that can store information on the positions of a plurality of subjects, and the position storage unit 144 has coordinates of an image area that indicates the subject position. It has subject detection information such as value and subject number.
The light source analysis processing unit 14 has a function of analyzing (detecting) an image in the detection position range specified by the coordinates when the detection position coordinates stored in the position storage unit 144 exist.
The subject position determination unit 17 stores the detection information in the position storage unit 144.

The light source analysis processing unit 14 is, for example, two modes that are designated by a control system (not shown) or automatically switched according to the presence or absence of detection information in the position storage unit 144, specifically, an all-pixel detection mode and a subject position detection mode. It is possible to operate with.
In the all-pixel detection mode, the light source analysis processing unit 14 does not specify a detection range in the initial state where position information or the like is not stored in the position storage unit 144. Perform analysis processing.
Based on the detection result in the all-pixel detection mode, the subject position determination unit 17 described later detects information regarding the positions of a plurality of subjects, and the detection information is stored in the position storage unit 144.
For example, when this detection information is stored in the position storage unit 144, the light source analysis processing unit 14 switches from the all-pixel detection mode to the subject position detection mode.
In the subject position detection mode, the light source analysis processing unit 14 analyzes (detects) an image in the detection position range specified by the coordinates based on the detection position coordinates and the like stored in the position storage unit 144.
Since the light source analysis processing unit 14 is provided, the detection system 10 can detect only the position of the light source or the subject irradiated with the light source, and does not detect the position excluded as the subject. Is also effective and can be detected with high accuracy.

In the initial state described above, the filter processing unit 15 performs noise reduction on the entire image by filter processing and outputs the noise to the determination unit 16.
The filter processing unit 15 performs noise reduction on the n detected images in the light source analysis processing unit 14 or eliminates a portion that has not been detected by the filter processing, and outputs the result to the determination unit 16.
The filter processing unit 15 is suitable for the subject sensitivity value at the position from the subject sensitivity value (located in the image range Mn specified by the position storage unit) included in the attribute descriptor Patt [pt] of the subject state storage unit 18. Subject threshold determination processing is performed. This threshold corresponds to a noise removal threshold.

In the above-described initial state, the determination unit 16 is output from the arithmetic processing unit 143 and based on the square sum value (A ² + B ² ) of the entire image that has been reduced in noise by the filter processing unit 15. For example, it is determined whether the subject imaged in (1) is stationary or moving (determining the detection state). Details of the operation of the determination unit 16 will be described later.
Based on the square sum value (A ² + B ² ) of the detected image that is output from the arithmetic processing unit 143 and from which the filter processing unit 15 has eliminated noise and has not been detected, the determination unit 16 For example, it is determined whether the subject imaged at 12 is stationary or moving (detection state is determined). Details of the operation of the determination unit 16 will be described later.
The determination unit 16 is suitable for the detected response speed value of the position from the response speed value (located in the image range Mn specified by the position storage unit) included in the attribute descriptor Patt [pt] of the subject state storage unit 18. The detection judgment process is performed at the response speed.
The determination unit 16 includes group information (group-specific descriptor Grp [pt], group connection descriptor GrpCON [g] stored in the subject state storage unit 18. no]) and can be re-determined in units of groups according to the group information.

  The subject position determination unit 17 stores the position search processing unit 171 that searches for the position of the subject from all the images from the detection state obtained by the determination unit 16 and the position search result of the position search processing unit 171. A search information storage unit 172 is included.

FIGS. 3A and 3B are diagrams conceptually showing states before and after the position of a subject in the subject position determination unit according to the present embodiment.
As shown in FIG. 3A, the subjects OBJ1 and OBJ2 before position determination are searched, and as shown in FIG. 3B, the subjects OBJ1 and OBJ2 are within the range shown by the rectangular frames DTRG1 and DTRG2 as shown in FIG. The position is determined, and the range becomes the analysis target of the light source analysis processing unit 14 and the detection target of the determination unit 16.
The detection information [pt] such as the range after the position determination is stored in the position storage unit 144 of the light source analysis processing unit 14. In the present embodiment, as described above, there are a subject position detection mode in which only the detection of the range is possible and an all image detection mode for all images.
For example, in an application where it is necessary to detect only a subject at a specific position, the operation is performed in the subject position detection mode in the range stored in the position storage unit 144.
In that case, as described above, in order to set a specific position, the subject position determination unit 17 first searches the subject target position and stores it in the position storage unit 144, and thereafter only the detection of the stored position is performed. Applicable to use.

The subject position determination unit 17 determines the detection range from the size of the subject.
In the subject position determination unit 17, the detection range is determined using the first mode when the (x, y) width of the detection range DTRG is fixed to one and the (x, y) width according to the size of the subject. Second, a table value detection range DTRG having a size exceeding (or below) the current (x, y) width is selected from a plurality of tables prepared in advance with a (x, y) width. There are two modes:
The (x, y) width table of the detection range DTRG is stored in the position search information storage unit 172, for example.
The subject position determination unit 17 can select either the first mode or the second mode, and has a configuration having these functions.
This detection range is determined from a table in which the size of the subject is prepared in advance and the detection range is determined, so that the size and position of the subject can be detected at high speed.

  FIG. 4 is a diagram illustrating an example of (x, y) width table information of the detection range referred to for position determination in the subject position determination unit 17 according to the present embodiment.

In FIG. 4, “No” indicates the number of (x, y) width information of the subject detection range. “X, y” indicates the size information of the object detection range DTRG, and sBlk indicates the number of search blocks (number of pixels).
In the example of the (x, y) width table TBL2, the detection range DTRG of “No. 1” is “10 × 10” and the number of blocks is “2”.
The detection range DTRG of “No. 2” is “30 × 30” and the number of blocks is “4”.
The detection range DTRG of “No. 3” is “100 × 100” and the number of blocks is “8”.
The detection range DTRG of “No. 4” is “300 × 300” and the number of blocks is “12”.
The position search processing unit 171 of the subject position determination unit 17 refers to the (x, y) width table TBL2, and searches, for example, in ascending order from the smaller “No” or in descending order from the larger “No”. The detection range most suitable for the target subject is determined.

The subject position determination unit 17 is configured to be able to finely adjust the detection range DTRG from the size of the subject.
For fine adjustment of the detection range, from the state where the detection range DTRG (x, y) is determined, the fine adjustment value table prepared in advance or the fine adjustment formula [x1 = x * sP1, y1 = y * sP2] x, y) The configuration has a function of finely adjusting the width.
Here, “sP1” and “sP2” are adjustment parameters and take values of, for example, 1 <sP1, sP2 <2.
With this function, even if a small shake or movement occurs in a subject that can be detected within the normal detection range, it can be detected without departing from the subject range.
This is particularly effective when the subject is a light source.

  As described above, the subject position determination unit 17 searches for the position of the subject from all the images based on the detection state obtained by the determination unit 16 in the position search processing unit 171, and the position search result is stored in the position search information storage unit. Stored in 172. Thereby, the position of the subject is determined.

  The subject position determination unit 17 has a plurality of pieces of detection information pt of the light source or the subject position irradiated on the light source in the position search information storage unit 172 as M [pt].

FIG. 5 is a diagram illustrating an example of detection information stored in the position search information storage unit according to the present embodiment.
In the position search information storage unit 172, as the detection information M [pt], position information [(x1, y1) − (x2, y2)] regarding the detection range is stored in order from No. 0.

The detection system 10 of the present embodiment has various attributes in the state of each detection range, and has a subject state storage unit 18 that stores the state change of the attribute, and the state change state is indicated by the filter processing unit 15. And the determination part 16 can acquire and refer (browse).
As the various attributes, response speed, subject sensitivity, light source failure status, other statuses, determination results, and the like can be stored in the subject status storage unit 18.
Further, in the detection system 10 of the present embodiment, each detection range is associated as an arbitrary group, the grouped state can be stored in the subject state storage unit 18, and a parameter for specifying a result determination condition for each group is set. It is possible to memorize and acquire and refer to (view) state determination and change in units of groups.
In addition, it is possible to obtain and output the operation determination result by logical operation by logical sum, logical product, or comparison operation as =,>, <, ≠, or independently as a parameter for grouping and determining the result. .
Further, the detection system 10 has a function of displaying the status of each grouping information and attribute information on a display system (not shown).

  The subject position determination unit 17 associates the detection information M [pt] stored in the position search information storage unit 172 with the attribute descriptor Patt specific to the detection information pt in the subject state storage unit 18 with respect to the detection information pt. [Pt] is set (stored).

FIG. 6 is a diagram illustrating an example of the attribute descriptor stored in the subject state storage unit according to the present embodiment.
As shown in FIG. 6, the attribute descriptor Patt [pt] includes a response speed (RV), a detection sensitivity (DS), a failure state (TS), and other statuses (status STS for storing the current status and notifying the status) ), A determination result (determination result DRST for notifying the detection result).

The attribute descriptor Patt [pt] stored in the subject state storage unit 18 is referred to in the determination process of the filter processing unit 15 and the detection state determination process of the determination unit 16.
As described above, in the first process of the present embodiment, the detection information that is one detection range in the position detection of the light source or the subject irradiated with the light source has unique detection information. As a result, detection conditions can be set and notification of detection states can be set by individual detection parameters in a plurality of detection ranges. For this reason, since the detection determination result can be obtained by setting the optimum conditions for the installation environment and the detection target of the detection range, there is an effect of providing an accurate and highly accurate detection result according to the purpose.

  The subject position determination unit 17 sets (stores) a group-specific descriptor Grp [pt] unique to the detection information pt in the subject state storage unit 18 for one detection information pt of the light source or the subject position irradiated on the light source. .

FIG. 7 is a diagram showing an example of the group-specific descriptor stored in the subject state storage unit according to the present embodiment.
As shown in FIG. 7, the group-specific descriptor Grp [pt] includes a group number (group GRPN to which pt belongs), operation information (operation expression OPR of a member belonging to the group), and determination result (group member attribute descriptor). A determination result ORST) based on a calculation result for the determination result.

The group-specific descriptor Grp [pt] stored in the subject state storage unit 18 is referred to in the detection state determination process in the determination unit 16.
As described above, in the second process of the present embodiment, the detection results of the plurality of light source positions obtained in the first process are obtained in the detection information that is one detection range in the position detection of the light source or the subject irradiated to the light source. Group and judge. Thereby, conditions can be set by a plurality of detection ranges, and an optimum detection determination result can be obtained for the installation environment and the detection target. Therefore, there is an effect of providing an accurate and highly accurate detection result according to the purpose.

The subject position determination unit 17 connects the group-specific descriptor Grp [pt] unique to the detection information pt to the subject state storage unit 18 for one detection information pt of the light source or the subject position irradiated to the light source. Descriptor GrpCON [g no] is set (stored).
The group association determination process is performed in the group association determination unit 19.

FIG. 8 is a diagram illustrating an example of the group connection descriptor stored in the subject state storage unit according to the present embodiment.
Group connection descriptor GrpCON [g no], as shown in FIG. 8, for each group number (group GRPN to which pt belongs), operation information (operation expression OPR of a member belonging to the group), determination result (operation for the determination result of the attribute descriptor of the group member) The result includes a determination result ORST), the number of connections (CTN), and a connection group number (CGRPN).

Group connection descriptor GrpCON [g stored in the subject state storage unit 18 no] is referred to in the detection state determination process in the determination unit 16.

  Here, the range after position determination in the subject position determination unit 17 will be described.

The detection range after the position determination by the subject position determination unit 17 is, for example, the range shown in FIGS. 9 and 10.
FIG. 9 shows a detection range after position determination when detection is performed by one imaging device (camera).
FIG. 10 shows a detection range after position determination when a four-screen dividing device is used with four imaging devices (cameras).

  In the detection system of the present embodiment, as a characteristic first process, in the acquired detection range after position determination as shown in FIG. 9 or FIG. 10, attribute parameters (response speed, Subject sensitivity, light source failure status, various statuses, determination results, etc.). Thereby, this embodiment can provide the highly accurate detection system which can adjust and detect the detection position with respect to a light source separately.

For example, FIG. 9 is a conceptual diagram assuming a normal detection range, and the positions and areas of the detection ranges of the light sources 11-1 to 11-4 can be individually set. The response speed is the same, and the sensitivity of the subject is also the same.
Therefore, highly accurate detection determination is possible in the conceptual diagram of FIG.
According to the present embodiment, as in the example of FIG. 10, the distance to the light source and the brightness around the light source are different. For example, the light source 11-1 is dedicated to nighttime, the light source 11-2 is outdoors, the light source 11-3 is indoors, and the light source 11-4 is dark room.
In such cases and detection response speeds, for example, the light source 11-1 is the person detection, the light source 11-2 is the stop vehicle detection, the light source 11-3 is the luggage detection, and the light source 11-4 is the person detection optimum detection response speed. Therefore, an unnecessary detection determination is not included, and an optimal target determination result can be expected.

In this embodiment, as a characteristic second process, as shown in FIG. 11 and FIG. 12, in the acquired detection range after position determination, detection determination for each light source after position determination is performed, and then the group A detection system that can be re-determined in units is realized.
FIG. 11 shows a group setting example in which redetermination is performed on a group basis by dividing into two groups each including a plurality of detection ranges.
FIG. 12 shows a group setting example in which redetermination is performed in units of groups divided into three groups each including one or a plurality of detection ranges.

For example, in the group-unit detection determination, the two light sources 11-1 and 11-3 shown in FIG. Judgment can be made by specifying the shape and size of overlapping objects.
Further, in group B, determination can be made by blocking one of the light sources by a logical sum operation (OR), so that it is possible to set conditions for an intruder in the group.
That is, the number of light sources belonging to the group can be arbitrarily specified, and detection conditions can be set according to the location and environment to be detected, and detection of the target can be determined with high accuracy.

  A basic detection position determination process in the subject position determination unit 17 according to the present embodiment, and specific first and second processes for applying an attribute parameter specific to detection determination after position determination will be described.

First, basic detection position determination processing in the subject position determination unit 17 according to the present embodiment will be specifically described with reference to FIGS.
FIGS. 13 and 14 are flowcharts for specifically explaining the basic detection position determination process in the subject position determination unit 17 according to the present embodiment, and FIG. 13 is a flowchart for performing the position determination process. FIG. 14 is a flowchart when the position determination process is not performed.
FIG. 15 is a diagram for explaining a method of searching for a subject of one light source or reflected light.
FIG. 16 is a diagram for explaining the detection range fine adjustment processing.
The following processing is performed mainly by the position search processing unit 171. Here, the processing will be described as processing by the subject position determination unit 17.

The subject position determination unit 17 determines whether or not to perform position determination processing (ST1).
When the subject position determination unit 17 determines that the position determination process is to be performed in step ST1, the subject position determination unit 17 performs detection (search) with reference to the (x, y) width table TBL2 stored in the position search information storage unit 172. The (x, y) width of the range DTRG is determined (ST2).
Then, the subject position determination unit 17 clears a storage area of information regarding the detection position in the position storage unit 144 as a detection position memory of the light source analysis processing unit 14, for example (ST3).
Next, the subject position determination unit 17 investigates the number of blocks of the target frequency with the (x, y) width of the detection range DTRG (ST4).

The process in step ST4 will be described with reference to FIGS.
The subject position determination unit 17 searches for a subject of one light source or reflected light by referring to the (x, y) width table TBL2 by a method as shown in FIGS.
First, as shown in FIG. 15A, the minimum unit of search is set to one block BLK.
FIG. 15A shows a 2 × 2 case as an example of a vertical × horizontal search pixel spix.
The detection intensity of one block is a value obtained by dividing the sum of all pixels by 2 × 2.
Here, the search is started.

As shown in FIG. 15B, one horizontal line LLN search process is performed.
In this case, the search block sBlk = 2, and the 2 × 2 block is searched in the horizontal line (x direction) LLN.
When the search block sBlk is 2, since it is vertical (y) 2 and horizontal (x) 2, the number of detected blocks is counted.
If the block BLK is detected by the blocks indicated by reference numerals 2, 3, and 4, the count value is 3.
In the case of a table in which the number of search blocks sBlk is large, the subject position determination unit 17 repeats the process with reference to the next number sBlk in the detection range table until the count value becomes 1.
Information on the detected horizontal line LLN is stored in the position search information storage unit 172.
The subject position determination unit 17 searches the entire process for every 2 × 2 blocks in the above process.
Next, one vertical line search process is performed.

As shown in FIG. 15C, one vertical line VLN search process is performed.
The subject position determination unit 17 searches the detection line of the horizontal line LLN stored in the position search information storage unit 172 with a block width indicated by the number of search blocks sBlk in the vertical direction.
The search method is the same as the search of the horizontal line LLN. In the case of a table in which the number of search blocks sBlk is large, the process is repeated with reference to the next number sBlk in the detection range table until the count value becomes 1.
The detected vertical line VLN is stored in the position search information storage unit 172. The subject position determination unit 17 searches the entire process for every 2 × 2 blocks in the above process.
Next, a search process for the detection range DTRG is performed.

As shown in FIG. 15D, the detection process of the detection range DTRG is performed.
A continuous vertical and horizontal block detected by the horizontal line LLN and the vertical line VLN from the above processing is defined as one range.
The total average value of the detection intensities of the blocks in the range is obtained.
Next, the detection range DTRG is determined.
Also in this case, continuous vertical and horizontal blocks that can be detected by the horizontal line LLN and the vertical line VLN from the above processing are set as one range.
The total average value of the detection intensities of the blocks in the range is obtained.
Then, the subject position determination unit 17 determines the detection range [(x, y) − (xe, ye)] DTRG.
Then, fine adjustment is performed within the determination range with the magnification of the fine adjustment parameters sP1 and sP2.
The above processing can be performed simultaneously with a plurality of light sources.

The subject position determination unit 17 performs fine adjustment processing of the detection range DTRG by a method as shown in FIGS.
The subject position determination unit 17 finely adjusts the detection intensity in each determination range, investigates the detection intensity in four directions or eight directions for each detection range, and finally determines the detection intensity in a place with the highest detection intensity.
In this example, the detection intensity on one block is investigated in FIG. 16 (B), the detection intensity on one block right is examined in FIG. 16 (C), and the detection intensity below one block is examined in FIG. 16 (D). Then, the detected intensity on the left of one block is investigated in FIG.
Then, in FIG. 16F, a final detection range DTRG is determined at a place with the highest detection intensity.
In other words, the place where the subject OBJ is located at substantially the center of the detection range DTRG is determined as the final detection range DTRG.

After examining the number of blocks of the target frequency in step ST4, the subject position determination unit 17 determines whether or not the number of blocks of the target frequency is greater than 0 (ST5).
If it is determined in step ST5 that the number of blocks of the target frequency is greater than 0, the subject position determination unit 17 stores the detected position information obtained by searching the position storage unit 144 of the light source analysis processing unit 14 (ST6).
Then, the number “No” in the table TBL1 of the position storage unit 144 is incremented by 1 (ST7).
The subject position determination unit 17 designates the next detection range DTRG (x, y) (ST8).
If the subject position determination unit 17 determines in step ST5 that the number of blocks of the target frequency is 0, the process proceeds to step ST8 without performing steps ST6 and ST7.
The subject position determination unit 17 repeats the processes of steps ST4 to ST8 until the detection of the target image is completed (ST9).
In step ST8, when the detection of the target image is completed, areas with numbers consecutive in the (x, y) direction are integrated from the detected position information in the position storage unit 144 (ST10), and the number of detected positions is acquired (ST11). .

If the subject position determination unit 17 determines not to perform the position determination process in step ST1, the subject position determination unit 17 proceeds to the process from step ST12 in FIG.
The subject position determination unit 17 acquires the designated number from the position storage unit 144 (ST12).
Here, the subject position determination unit 17 determines whether or not there is a designated number (ST13).
If it is determined in step ST13 that there is a designated number, the subject position determining unit 17 acquires (x, y) width information of the detection range DTRG in the position storage unit 144 from the designated number (ST14), and the subject in the detection range DTRG is obtained. A state is detected (searched) (ST15).
Then, the number “No” in the table TBL1 of the position storage unit 114 is incremented by 1 (ST16).
The subject position determination unit 17 repeats the processes of steps ST14 to ST16 until the detection of the target image is completed (ST17).
If the subject position determination unit 17 determines that there is no designated number in step ST13, the subject position determination unit 17 detects (searches) the subject states of all pixels without performing the processing of steps ST14 to ST17 (ST18).

Next, a series of operations of the detection system according to the present embodiment will be described with reference to FIGS.
First, the subject position determination process in the detection system will be mainly described.
Thereafter, the attribute descriptor Patt [pt] specific to the detection information pt set in the subject state storage unit 18, the group-specific descriptor Grp [pt], and the group connection descriptor GrpCON [g no] will be described focusing on the filter processing of the filter processing unit 15 and the detection state determination processing of the determination unit 16.

  FIG. 17 is a flowchart for explaining an outline of the operation of the detection system according to the present embodiment, focusing on subject position determination processing.

First, the luminance of the light source 11 within the charge accumulation time of the imaging device 12 is changed by 4n times the field period of the imaging device 12 (ST21).
Next, a luminance signal is acquired by the luminance signal extraction unit 13 every n fields in the field unit from the imaging device 12 (ST22), and this luminance signal is output to the first calculation unit 141 and the second calculation unit 142.
The first arithmetic unit 141 obtains the time average SAC of the level difference AC of the luminance signal level in the projection area REG of the mth and (m + 2) th fields. Further, the second arithmetic unit 142 obtains the time average SBD of the level difference BD of the luminance signal level in the projection area REG of the (m + 1) th and (m + 3) th fields (ST23).
These time averages SAC and SBD are output to the arithmetic processing unit 143.
Subsequently, the arithmetic processing unit 143 obtains the square sum SACBD of the time average SAC and SBD (ST24), and outputs it to the determination unit 16 via the filter processing unit 15.
The determination unit 16 determines the state of the subject according to the value of the square sum SACBD (ST25). The determination result is supplied to the subject position determination unit 17.
The subject position determination unit 17 determines whether or not to determine the subject position (ST26).
Here, when the subject position is determined, the subject position determination unit 17 detects the state of the subject and acquires information regarding the detection position (ST27), and the detected position information is stored in the position storage unit 144 of the light source analysis processing unit 14. Remembered.
When the subject position is not determined, the subject position determination unit 17 acquires the specified position (specified number) from the position information stored in the position storage unit 144 (ST28), and detects the state of the subject at the specified position. (ST29).
Then, when performing steps ST23 and ST24 in the light source analysis processing unit 14, based on the detection position coordinates stored in the position storage unit 144, one or more images of the detection position range specified by the coordinates are obtained. Analysis (detection) is performed.
By this processing of the light source analysis processing unit 14, the present detection system 10 can detect only the position of the light source or the subject irradiated with the light source, and does not detect the position excluded as the subject. It is effective and can be detected with high accuracy.

Further, the subject position determination unit 17 associates the detection information pt with the detection information pt in the subject state storage unit 18 in association with the detection information M [pt] stored in the position search information storage unit 172. Descriptor Patt [pt] is set.
In the subject position determination unit 17, a group-specific descriptor Grp [pt] unique to the detection information pt is set in the subject state storage unit 18 for one detection information pt of the light source or the subject position irradiated to the light source. .
In addition, in the subject position determination unit 17, a group-specific descriptor Grp [pt] specific to the detection information pt is connected to the subject state storage unit 18 for one detection information pt of the light source or the subject position irradiated to the light source. Group connection descriptor GrpCON [g no] is set.

In the arithmetic processing unit 143 according to the present embodiment, the square sum SACBD of the time average SAC and SBD is obtained, and the sum of the time average SAC and SBD (S _AC + S _BD ) is determined by the determination unit 16. It can also be used.

Next, the attribute descriptor Patt [pt] specific to the detection information pt set in the subject state storage unit 18, the group descriptor Grp [pt], and the group connection descriptor GrpCON [g No] will be described with reference to FIGS. 18 to 24, focusing on the filtering process of the filter processing unit 15 and the determination process of the detection state of the determination unit 16.
In the following, it is assumed that detection position determination is performed and detection information regarding the positions of a plurality of subjects is stored in the position storage unit 144 serving as a detection position memory, as in the process of FIG.

FIG. 18 is a flowchart for explaining an outline of the operation of the detection system according to the present embodiment, focusing on subject position determination processing.
FIG. 19 is a flowchart showing a process for acquiring the detection sensitivity value of FIG. 17 and determining the detection sensitivity.
FIG. 20 is a flowchart showing a process of acquiring the response speed value of FIG. 17 and setting the response speed value as a threshold value.
FIG. 21 is a flowchart showing processing for acquiring the failure state of FIG. 17 and determining the failure state.
FIG. 22 is a flowchart showing processing for acquiring the other status of FIG. 17 and determining the other status state.
FIG. 23 is a flowchart showing a process for acquiring the group number information of FIG. 17 and determining the state by group.
FIG. 24 is a flowchart illustrating a process of acquiring the group connection target of FIG. 17 and detecting and determining the group connection state.

First, the luminance of the light source 11 within the charge accumulation time of the imaging device 12 is changed by 4n times the field period of the imaging device 12 (ST31).
Next, a luminance signal is acquired by the luminance signal extraction unit 13 every n fields in the field unit from the imaging device 12 (ST32), and the luminance signal is output to the first calculation unit 141 and the second calculation unit 142.
In the light source analysis processing unit 14, the detected position information is stored in the position storage unit 144 of the light source analysis processing unit 14. Then, when performing steps ST23 and ST24 in the light source analysis processing unit 14, based on the detection position coordinates stored in the position storage unit 144, one or more images of the detection position range specified by the coordinates are obtained. Analysis (detection) is performed (ST33).
Specifically, in the detection position range, as described above, the first arithmetic unit 141 obtains the time average SAC of the level difference AC of the luminance signal level in the projection area REG of the mth and (m + 2) th fields. . Further, the second arithmetic unit 142 obtains the time average SBD of the level difference BD of the luminance signal level in the projection area REG of the (m + 1) th and (m + 3) th fields (ST34).
These time averages SAC and SBD are output to the arithmetic processing unit 143.
Next, the arithmetic processing unit 143 obtains the square sum SACBD of the time average SAC and SBD (ST35) and outputs the result to the filter processing unit 15.

The filter processing unit 15 performs noise reduction on the n detected images in the light source analysis processing unit 14 or eliminates a portion that has not been detected, and outputs the detected image to the determination unit 16.
At this time, the filter processing unit 15 acquires the number pt of the light source (subject), and includes the subject sensitivity value (image range Mn specified by the position storage unit) included in the attribute descriptor Patt [pt] of the subject state storage unit 18. To get to). Then, the filter processing unit 15 performs subject threshold determination processing suitable for the subject sensitivity value at that position (ST36). Thereby, noise reduction is achieved.
In step ST36, as shown in FIG. 19, the filter processing unit 15 determines whether or not the detection sensitivity is greater than the threshold value (ST361). The result is set to 1 (ST362), and when it is not large, there is an obstruction (subject) and the threshold determination result is set to 0 (ST363).

In the determination unit 16, imaging is performed based on the value of the square sum (A ² + B ² ) of the detected image output from the arithmetic processing unit 143 and from which noise reduction or a portion that has not been detected by the filter processing unit 15 is deleted. It is determined whether the subject imaged by the device 12 is stationary or moving, for example (detection state is determined).
At this time, the determination unit 16 acquires the light source (subject) number pt and is included in the attribute descriptor Patt [pt] of the subject state storage unit 18 (the range of the image specified by the position storage unit). Is located). Then, the determination unit 16 determines a detection time from the acquired detection response speed value of the position, and performs detection determination processing at a response speed suitable for the position (ST37).
In step ST37, as shown in FIG. 20, the determination unit 16 acquires the value of the speed counter from the response speed value table (ST371), and determines whether or not the interruption occurrence count value is larger than the value of the speed counter. (ST372).
When the interruption occurrence count value is not larger than the value of the speed counter, it is assumed that there is no obstruction (subject), the interruption occurrence count value is maintained as it is (+0) (ST373), and 0 is set as the interruption determination result. (ST374).
When the interruption occurrence count value is larger than the value of the speed counter, the interruption position information is acquired assuming that there is an obstruction (subject) (ST375), the interruption occurrence count value is cleared (ST376), and 1 as the interruption determination result. It is set (ST377).

Next, the determination unit 16 obtains the number pt of the light source (subject), obtains the failure state included in the attribute descriptor Patt [pt] of the subject state storage unit 18, and breaks down based on the information. The state is determined (ST38).
In step ST38, as shown in FIG. 21, the determination unit 16 determines whether or not the failure is equal to that of the state value (ST381), and if equal, 1 is set as a failure (ST382). If they are not equal, 0 is set as normal (ST383).

Next, the determination unit 16 obtains the number pt of the light source (subject), obtains another status included in the attribute descriptor Patt [pt] of the subject state storage unit 18, and based on the information. Another status state is determined (ST39).
In step ST39, as shown in FIG. 22, the determination unit 16 compares the status and the state value (ST391). In the case of the state 1, the processing of the state 1 is performed (ST392). Processing in state 2 is performed (ST393).

And the determination part 16 acquires the determination result of a light source number (ST40).
The determination processing with reference to the attribute descriptor Patt [pt] in the subject state storage unit 18 has been described above.

Next, the determination unit 16 obtains the number pt of the light source (subject), obtains group number information included in the group-specific descriptor Grp [pt] in the subject state storage unit 18, and based on the information. A state by group is determined (ST41).
In step ST41, as shown in FIG. 23, the determination unit 16 sets the group number to 0 (ST411), and determines whether the group determination is completed (ST412).
If the determination is not completed, determination section 16 determines whether or not this group number exists (ST413).
When the group number exists, the determination unit 16 acquires the calculation information of the group number from the subject state storage unit 18 (ST414), and performs a logical operation on all the determination results of the light source numbers belonging to this group number (STEP 414). ST415).
Thereby, the determination unit 16 acquires the determination result of this group number (ST416), increments the group number by 1 (ST417), and returns to the process of step ST412.
If the currently set group number does not exist in step ST413, the process proceeds to step ST417, and the group number is incremented by 1, and the process starts from step ST412.

And the determination part 16 acquires the determination result according to group (ST42).
The determination processing with reference to the group-specific descriptor Grp [pt] in the subject state storage unit 18 has been described above.

Next, in the determination unit 16, the group connection descriptor GrpCON [g in the subject state storage unit 18. no] is acquired, and sample determination is performed based on the information in the group connection state (ST43).
In step ST43, as shown in FIG. 24, the determination unit 16 acquires the number of groups (ST431), and determines whether or not the number of groups is 0 (ST432).
If the number of groups is not 0, determination section 16 determines whether or not a connected group exists in this group number (ST433).
When there is a connection number in the group number, the determination unit 16 acquires operation information of the group number to be connected from the subject state storage unit 18 (ST434), and performs a logical operation on all the determination results of the connection group number. (ST435).
Thereby, in the determination part 16, the determination result of this group number is acquired (ST436), a count value is -1 (ST437), and it returns to the process of step ST432.
In step ST433, if there is no linked group in the currently set group number, the process proceeds to step ST437, the count value is decremented by 1, and the process starts from step ST432.

And the determination part 16 acquires the determination result of group connection (ST44).
The above is the group connection descriptor GrpCON [g in the subject state storage unit 18. no]].
The determination unit 16 outputs the determination result obtained as described above (ST45).

Next, other configurations and functions of the detection system according to the present embodiment will be described in detail.
First, the configuration of the CCD of the imaging device 12 according to the present embodiment will be described.

  FIG. 25 is a diagram showing an example for explaining the structure of the CCD according to the present embodiment.

25 is an interline transfer, and includes a photodiode PD31, a vertical transfer CCD32, a horizontal transfer CCD33, and an amplifier.
The photodiodes PD31 are arranged in a matrix. The photodiodes PD31 arranged in the vertical line direction are connected to a vertical transfer CCD 32 for transferring charges for each column. The end of each vertical transfer CCD 32 is connected to a horizontal transfer CCD 33 that transfers charges to the amplifier. An amplifier 34 is connected to the output side of the horizontal transfer CCD 33.

The video scanning method is interlaced, and one screen is interlaced scanning, and is composed of an odd field and an even field.
First, light enters the photodiode PD31, and charges are accumulated in the photodiode PD31 during the charge accumulation time. During this time, the photodiode PD31 and the vertical transfer CCD 32 are disconnected.
When the charge accumulation time ends, the photodiode PD31 and the vertical transfer CCD 32 are brought into conduction, and the accumulated charge is transferred to the vertical transfer CCD 32. Immediately after this, the photodiode PD31 and the vertical transfer CCD 32 are disconnected, and the next charge accumulation is started in the photodiode PD31. The charges transferred to the vertical transfer CCD 32 are transferred to the horizontal transfer CCD 33 for each horizontal line and input to the amplifier 34.
The frequency until the charge is transferred from the vertical transfer CCD 32 to the horizontal transfer CCD 33 for each horizontal line is the horizontal scanning frequency of 15.734 Hz of the CCD 30. When all the charges of the vertical transfer CCD 32 are transferred to the horizontal transfer CCD 33, the vertical transfer CCD 32 and the photodiode PD31 are conducted again, and the charge of the photodiode PD31 is transferred to the vertical transfer CCD 32. In the case of a field accumulation CCD, charges are accumulated in the photodiode PD31 by photoelectric conversion, and the transfer frequency until this charge is transferred from the photodiode PD31 to the vertical transfer CCD 32 is 59.94 Hz.

  FIG. 26 is a diagram for explaining the time series of the CCD 30 in FIG.

As shown in FIG. 26, it is assumed that a required time until charge is accumulated in the photodiode PD31 by photoelectric conversion is ΔT1, and a required time until the charge is transferred from the photodiode PD31 to the vertical transfer CCD 32 is ΔT2.
As can be seen from FIG. 26, the light energy incident on the CCD 30 is sampled at the charge accumulation period ΔT = ΔT1 + ΔT2 = (1 / 59.94) seconds while being integrated during the charge accumulation time ΔT1.

As shown in FIG. 1, a luminance signal is extracted by a luminance signal extraction unit 13 from a captured image signal captured by the imaging device 12, and the luminance signal is input to the light source analysis processing unit 14.
Here, a method of reading out pixels from the CCD 30 (see FIG. 25) according to the present embodiment will be described.

FIG. 27 is a diagram showing an arrangement example of pixels of a single-plate complementary color filter type CCD.
FIG. 28 is a diagram illustrating an example of a combination of color signals in the odd field OFD and the even field EFD.

The color filter of the pixel is composed of Ye (yellow), Cy (cyan), Mg (magenta), and G (green), and is arranged as shown in FIG. Pixels are read by adding the upper and lower pixels. The combination to be added is shifted by one column between the odd field OFD and the even field EFD. Specifically, in the n-th line of the odd field OFD, (C11 + C21), (C12 + C22), (C13 + C23), (C14 + C24), (C15 + C25),... In the n-line of the even field EFD, (C21 + C31), (C22 + C32), (C23 + C33), (C24 + C34), (C25 + C35),...
Therefore, color signals are output in the odd field OFD and the even field EFD as shown in FIG.
In any case, the same color pattern of a combination of Ye, Cy, Mg, and G is repeated in a two-pixel cycle.
In other words, the color signal appears superimposed on a frequency of two pixel periods or more. Therefore, if this color signal is passed through a low-pass filter having a cutoff frequency of two pixel periods, the color signal is lost and only a luminance signal is obtained.
Therefore, luminance information is sampled at a cycle of two pixels.

A projection area REG indicated by a circle in FIG. 27 shows a state in which an image of a subject by a light source is projected. It is assumed that the pixels C35, C36, C45, C46, C55, and C56 are completely in the projection region REG and are uniformly irradiated with light.
In the odd field OFD, the luminance information is read by a combination of C35, C36, C45, and C46 of the horizontal line (n + 1), and in the even field EFD, by a combination of C45, C46, C55, and C56 of the (n + 1) line of the horizontal line. Is done.

  As described above, the luminance signal among the signals from the imaging device 12 is output to the light source analysis processing unit 14. This luminance signal is input to the first calculation unit 141 and the second calculation unit 142 and subjected to predetermined processing.

  Next, a luminance signal processing method performed by the first calculation unit 141 and the second calculation unit 142 will be described with reference to FIG.

  FIG. 29 is a timing chart for explaining the signal processing method of the luminance signal of the light source analysis processing unit according to the present embodiment.

FIG. 29A is a diagram showing interline scanning of the imaging device 12, and shows a state of either the even field EFD or the odd field OFD. FIGS. 29B to 29E respectively show waveforms W1, W2, W3, and W4 that represent temporal changes in the luminance signal level processed by the light source analysis processing unit 14, and FIG. 29F changes at a constant cycle. It is a figure which shows the waveform W5 of the sine wave to do.
The odd field OFD and even field EFD scan one frame. That is, as shown in FIG. 29A, one frame is scanned by A and B and C and D.
In the following description, f represents frequency, t represents time, θ represents phase difference, and ω satisfies (ω = 2πf). Note that π is the circumference ratio.

Waveforms W1 and W2 illustrated in FIGS. 29B and 29C are waveforms for deriving functions of waveforms indicated by a waveform W3 and a waveform W4 described later.
A waveform W3 illustrated in FIG. 29D is a time development distribution of a function for obtaining the level difference AC when the luminance level difference between the luminance signal of the A field and the luminance signal of the C field is the level difference AC. Indicates.
A waveform W4 shown in FIG. 29E is a function time for obtaining the level difference BD when the difference in luminance level between the luminance signal of the B field and the luminance signal of the D field is defined as the level difference BD. The development distribution is shown.
Waveform W3 is derived from waveform W1 and waveform W2, and is obtained by adding waveform W1 and waveform W2 and dividing by two. Waveform W4 is derived from waveform W1 and waveform W2, and is obtained by subtracting waveform W1 from waveform W2 and dividing it by 2.

At this time, a time average SAC that is a first time average of the level difference AC is calculated by the first calculation unit 141 shown in FIG. In addition, a time average SBD that is a second time average of the level difference BD is calculated by the second calculation unit 142.
Specifically, the time average SAC is calculated from the luminance level difference AC between the A field and the C field by a combination of C35, C36, C45, and C46.
Similarly, the time average SBD is calculated from the level difference BD between the B field and the D field by a combination of C45, C46, C55, and C56.

The calculation method of the time average is described.
The time average SAC of the level difference AC between the A field and the C field is calculated by multiplying the waveform W1 by the waveform W3 shown in FIG.
Similarly, the time average SBD of the level difference BD between the B field and the D field is shown in FIG. 29 (E) in a waveform representing the time change of the light applied to the pixel by the combination of C45, C46, C55, and C56. The time average SBD is calculated by multiplying the waveform W4 shown.

First, a method for calculating the time average SAC will be specifically described.
The waveform W3 is expressed by a mathematical expression. First, the waveform W1 and the waveform W2 can be expressed by the following Fourier series.

  Here, it is assumed that the waveforms W1 and W2 have the same period f2. From equation (1) and equation (2), waveform W3 can be expressed as equation (4).

  Incidentally, the waveform W5 having the period f1 shown in FIG. 29F can be expressed by a sine wave as shown in the equation (5).

  When the waveform W3 represented by the equation (4) is multiplied by the sine wave W5 represented by the equation (5), the equation (7) is obtained.

Next, the time average of the equation (7) from time 0 to time T is taken. Of the terms shown on the right side of the equation (7), the term including time t is an AC signal, so the time average is zero.
Therefore, only when (ω ₁ − (2n−1) ω ₂ = 0), the constant cos θ ₁ and the constant sin θ ₁ remain, and the time average SAC is expressed by the equation (8).

  In this way, the time average SAC is obtained by the first calculation unit 141. Similarly, the time average SBD is obtained by the second calculation unit 142 and is expressed by equation (9).

Now, the sum of squares (S _AC ² + S _BD ² ) of the time average SAC and SBD expressed by the equations (8) and (9) is expressed by the equation (10).

From this equation (10), when the frequency component (f ₁ = (2n−1) f ₂ ) is included in the light incident on the CCD 30 (see FIG. 25), it is expressed by the equation (10). Waveform components are detected.

Next, frequency components included in the light source 11 will be considered.
FIG. 30 is a diagram showing a waveform W6 for frequency components included in the light source 11. As shown in FIG. The light source 11 emits light at the luminance level L1 at the frequency f3 for the time τ.

This waveform W6 is developed into a Fourier series. The waveform W6 is a periodic function of a period (T ₃ = 1 / f ₃ ). When (ω ₃ = 2πf ₃ ), the waveform W6 is represented by a general formula of Fourier series as shown in Expression (11).

The coefficients a ₀ , a _n , and b _{n in the} equation (11) are obtained from the waveform W6 as in the equations (12) to (14).

  Therefore, the Fourier series of the waveform W6 is expressed by equation (15).

Therefore, when the blinking period of the light source 11 is set to four times the field period, that is, when (f ₃ = f ₂ ), the frequency coincides with the odd term from the expressions (7) and (15), and the time average SAC And the sum of the squares of SBD is given by equation (16).

  When the duty ratio of lighting of the light source 11 is D, it is expressed by equation (17).

    Therefore, the square sum SACBD of the time average SAC and SBD expressed by the equation (16) is expressed by the equation (18) when the equation (17) is used.

  By the way, the term (19) on the right side of the following equation (18) converges.

  The term (19) on the right side of the equation (18) takes a value as shown in Table 1 with respect to the duty ratio D. Table 1 is shown below.

  Based on Table 1, when the duty ratio D is taken on the horizontal axis and the square sum SACBD of the time average SAC and SBD is taken on the vertical axis, the relationship between the duty ratio D and the square sum SACBD is as shown in FIG. become.

From FIG. 31, it can be seen that the square sum SACBD becomes maximum at the duty ratio D = 0.5.
Therefore, the sum of squares SACBD expressed by the equation (18) is expressed by the following equation.

[Equation 15]
S _AC ² + S _BD ² = 0.08333L ₁ ² (20)

  As shown in equation (20), the arithmetic processing unit 143 detects the luminance of the light source 11 (see FIG. 1), and outputs the detection result (square sum SACBD) to the determination unit 16 via the filter processing unit 15. To do. This detection result is used for determining the state of the subject by the determination unit 16.

The light source 11 according to the present embodiment does not depend on a specific light source. Therefore, it is considered whether the luminance can be detected for other light sources.
Incandescent light bulbs and fluorescent lamps that are widely used as light sources are 100 Hz in regions where the power supply frequency is 50 Hz and 120 Hz in regions where 60 Hz. The field frequency of an NTSC television is 59.94 Hz, and the field frequency of a monitor used for a personal computer is 60 Hz or more so as not to flicker.

  The field frequency of the NTSC television is 59.94 Hz, and if the light source is caused to emit light at a quarter period, the frequency f2 of the luminance level difference is as follows.

[Equation 16]
f ₂ = 59.94 / 4 = 14.985 Hz (21)

  From the equations (7) and (15), the signal component is detected when the odd multiple of the frequency f2 matches the integer multiple of the frequency f3 of the light source 11.

  Table 2 is a table of values indicating the relationship between the light emission frequency of different light sources and the frequency in the difference in luminance signal level.

F1 in Table 2 is the frequency of the sine wave of Formula (5), f2 is the frequency shown in Formula (21), and f3 is the frequency of the light source 11, the frequency of illumination in the 50 Hz region, and the illumination in the 60 Hz region, respectively. Frequency, NTSC television field frequency, and monitor field frequency used in personal computers.
According to Table 2, up to m = 30, f3 is 100, 120, 59.94 Hz, and there is nothing that satisfies (n × f ₃ = (2m−1) × f ₂ ).

For example, regarding a monitor of a personal computer, if the field frequency is 60 Hz or more, there is a monitor that is scanned at 74.925 Hz as a possibility that the largest output is detected in the signal processing output of the detection system 10. When
That is, when f ₃ = 74.925 Hz, as shown in Table 2, (5 × f ₂ ), (15 × f ₂ ), (25 × f ₂ ), and (1 × f ₃ ), ( 3 × f ₃ ), (5 × f ₃ ). The signal level detected at this time is expressed by the following equation.

したがって、（２２）式で示される信号レベルは光源１１の１／２５のレベルであり、図１に図示していない信号処理で別に除去できる。

Therefore, the signal level expressed by the equation (22) is 1/25 of that of the light source 11 and can be removed separately by signal processing not shown in FIG.

  As described above, the detection system 10 detects the state of the light source or the subject irradiated on the light source without depending on the light emission frequency of the light source.

  As described above, according to the present embodiment, the background noise of the captured image can be removed, and the state of the subject irradiated with the light source or the light source can be detected.

According to the detection system according to the present embodiment, in the detection of the light source or the state of the subject irradiated to the light source, detection when there are a plurality of subjects can be performed for each subject, and tracking and capturing of the subject can be performed. By doing so, there is no need to detect the position of an unnecessary object that is not a subject, and the effect of detecting the state of the subject at high speed and with high accuracy can be obtained.
Moreover, since it does not depend on the light source, it does not depend on the specifications of the imaging device, and for example, a generally available camera can be used as the imaging device of the present detection system.
Furthermore, according to the present embodiment, in the detection of the state of the light source or the subject irradiated with the light source, when the detection when there are a plurality of subjects is also performed for each subject, the detection determination conditions can be individually set, This makes it possible to set appropriate conditions in accordance with the environment and location of the subject, so that there is an advantage that a target determination result that does not include an unnecessary determination result can be obtained with high accuracy.

Furthermore, this detection system uses a plurality of light sources and can transmit signals to the signal processing unit in parallel.
Alternatively, it is possible to provide a plurality of light source colors and perform wavelength multiplexing transmission of signals.
It is also possible to process the signal by appropriately blinking the light source.

[Second Embodiment]
Next, a second embodiment according to the present invention will be described.

In the second embodiment, the field accumulation / interlace imaging device 12 according to the first embodiment is replaced with a frame accumulation / interlace imaging device. At the same time, the luminance change period of the light source 11 according to the first embodiment is changed from 4n times the field period to 4n times the frame period. Accompanying this change in the change period, the luminance signal acquisition period is changed from every n fields to every 2n fields.
As described above, by changing the luminance change cycle of the light source 11 and the luminance signal acquisition cycle, the same effects as those of the first embodiment can be obtained.
Therefore, according to the present embodiment, the background noise of the captured image can be removed, the state of the light source or the subject irradiated with the light source can be detected, and even when there are a plurality of subjects, detection can be performed for each subject.

[Third Embodiment]
Next, a third embodiment according to the present invention will be described.

In the third embodiment, the field accumulation / interlace scanning imaging device 12 according to the first embodiment is replaced with a frame accumulation / non-interlace scanning imaging device.
As described above, even when a non-interlaced scanning imaging apparatus is used, the same effect as that of the first embodiment can be obtained.
Therefore, according to the present embodiment, the background noise of the captured image can be removed, the state of the light source or the subject irradiated with the light source can be detected, and even when there are a plurality of subjects, detection can be performed for each subject.

Note that the method described above in detail can be formed as a program according to the above-described procedure and executed by a computer such as a CPU.
Further, such a program can be configured to be accessed by a recording medium such as a semiconductor memory, a magnetic disk, an optical disk, a floppy (registered trademark) disk, or the like, and to execute the program by a computer in which the recording medium is set.

DESCRIPTION OF SYMBOLS 10 ... Detection system, 11 ... Light source, 12 ... Imaging device, 13 ... Luminance signal extraction part, 14 ... Light source analysis process part, 141 ... 1st calculating part (A) , 142... Second calculation unit (B), 143... Calculation processing unit, 144... Position storage unit, 15... Filter processing unit, 16. Part 171 ... position search processing part 172 ... position search information storage part 18 ... subject state storage part Patt [pt] ... attribute descriptor Grp [pt] ... group description Child, GrpCON [g no] ... group connection descriptor.

Claims (11)

At least one light source;
At least one imaging device for imaging the light source or a subject illuminated by the light source;
An analysis processing unit that performs analysis processing on a signal acquired from the imaging device;
A determination unit that performs a detection determination process that detects and determines the state of the light source or subject based on the analysis result of the analysis processing unit;
A position storage unit capable of storing detection information regarding a position including a detection range in at least an image of a plurality of subjects;
A state storage unit that stores various types of attribute information at least in the state of the detection range, and stores information including state changes of the attributes;
From the detection information obtained by the determination unit, the position and size of the subject in all images are searched to determine the position of the subject including the detection range, and the detection information including the detection range related to the subject is acquired, A subject position determination unit capable of storing detection information as information about the position in the position storage unit,
The analysis processing unit
The signal is acquired from the imaging device every predetermined scanning plane period, a time average of the signal level difference is obtained from a signal level difference of the signal between a plurality of different scanning planes, and further, based on the time average value Perform an analysis process to perform a predetermined calculation, and output the calculation result of the analysis process to the determination unit,
When the detection information is stored in the position storage unit, the analysis processing is selectively performed on the image in the detection position range specified in the detection information,
The determination unit is
A response speed value located in a predetermined range of the image specified by the position storage unit included in the information specifying the light source or the subject and the attribute information is acquired, and the detection time is determined from the detected response speed value of the acquired position. A detection system that performs detection / judgment processing at a response speed suitable for the position. The determination unit is
Obtain the value of the speed counter from the response speed value table, determine whether the interruption occurrence count value is greater than the value of the speed counter,
If the blocking occurrence count value is not larger than the value of the speed counter, it is assumed that there is no subject that is a blocking object, the blocking occurrence count value is kept as it is, and the blocking determination result information is set,
When the interruption occurrence count value is larger than the value of the speed counter, the interruption position information is acquired, the interruption occurrence count value is cleared, and the interruption determination result information is set, assuming that there is a subject that is an obstruction. Item 2. The detection system according to Item 1. A filter processing unit that performs at least noise reduction processing from a signal including the analysis result of the analysis processing unit and inputs the signal to the determination unit,
The filter processing unit
Of the attribute information stored in the state storage unit, a subject sensitivity value located within a predetermined range of the image specified by the position storage unit is obtained, and subject threshold determination processing suitable for the subject sensitivity value at the position is performed. The detection system according to claim 1 or 2. The filter processing unit
It is determined whether or not the subject sensitivity value acquired from the state storage unit is greater than a threshold value for noise removal. If the subject sensitivity value is greater than the threshold value, it is determined that there is no subject that is an obstruction. The determination result information is set, and when the subject sensitivity value is not larger than the threshold value, the threshold determination result information is set assuming that there is a subject that is an obstruction, and is supplied to the determination unit. Detection system. The state storage unit
A plurality of detection ranges are associated as an arbitrary group, the grouped state can be stored, and a parameter for specifying a result determination condition in the group unit is stored,
The determination unit is
The group information stored in the state storage unit can be acquired and re-determined in units of groups.
The subject position determination unit
A first process of adding specific attribute information including the response speed to the detection determination after position determination in the acquired detection range after position determination;
In the detection range after the position determination of the plurality of light sources or the subject irradiated with the light sources acquired in the first process, the determination results of the plurality of light sources or the subject positions are grouped and grouped based on parameters for which conditions are specified The detection system according to any one of claims 1 to 4, wherein the second process can be re-determined in units. The state storage unit
In addition to the attribute information, the group number to which the detection information belongs, the calculation information of the members belonging to the group, the group-specific information including the determination result by the calculation result for the determination result of the attribute information of the group member,
The determination unit is
Obtain information identifying the light source or subject, obtain group number information included in the group information, determine the group status based on the information,
When determining the status of each group,
It is determined whether or not this group number exists, and if the group number exists, the calculation information of the group number is acquired from the state storage unit, and the logic for all the determination results of the light source or subject belonging to this group number is obtained. The detection system according to claim 5, wherein a detection result of the group number is obtained by performing an operation. The state storage unit
In addition to the attribute information, for each group number to which the detection information belongs, group connection including calculation information of members belonging to the group, determination result based on the determination result of the attribute information of the group member, the number of connections, and the connected group number Remember information,
The determination unit is
Acquire group connection information included in the group connection information, and make a determination in the group connection state based on the information,
When judging in the connected state of the above group,
It is determined whether or not there is a linked group in this group number, and if there is a linked number in the group number, the operation information of the group number to be linked is acquired from the state storage unit, and all the linked group number determination results are obtained. The detection system according to claim 5, wherein a logical operation is performed on the group to obtain a determination result of the group number.

The subject position determination unit
A first mode in which the width of the detection range is fixed at only one;
In the determination of the detection range, the size of the subject is measured, and a table whose size exceeds the current coordinate (x, y) width or below the coordinate (x, y) width is prepared beforehand. A second mode for selecting a detection range of values,
Either the first mode or the second mode can be selected,
In the second mode,
After searching all the lines in the x and y directions for every predetermined number of search blocks, the detection range search process is performed, and the continuous vertical and horizontal blocks detected by the line search are regarded as one range. The detection system according to any one of claims 1 to 7, wherein a detection range is determined by obtaining a total average value of detection intensities of blocks. The subject position determination unit
The detection system according to claim 8, wherein in each determination range, the fine adjustment of the detection intensity is performed by investigating the detection intensity in four directions or eight directions for each detection range, and finally determining the detection intensity in a place with the highest detection intensity. An imaging step of imaging at least one light source or an object irradiated by the light source with at least one imaging device;
A signal is acquired from the imaging device every predetermined scanning plane period, a time average of the signal level difference is obtained from a signal level difference of the signal between a plurality of different scanning planes, and a predetermined average is obtained based on the time average value. An analysis process step for performing an analysis process for performing an operation;
A determination step for performing a detection determination process by detecting and determining the state of the light source or subject based on the analysis result of the analysis processing step;
A state storage step of storing various attribute information at least in the state of the detection range, and storing information including a state change of the attribute in the state storage unit;
From the detection information obtained in the determination step, the position and size of the subject in all images are searched to determine the position of the subject including the detection range, and the detection information including the detection range related to the subject is acquired, Subject position determination step for storing detection information in the position storage unit as information on the position,
In the analysis processing step,
When the detection information is stored in the position storage unit, including the step of selectively performing the analysis processing on the image of the detection position range specified in the detection information;
In the above determination step,
A response speed value located in a predetermined range of the image specified by the position storage unit included in the information specifying the light source or the subject and the attribute information is acquired, and the detection time is determined from the detected response speed value of the acquired position. And a signal processing method for the detection system, including a step of performing detection determination processing at a response speed suitable for the position. Imaging processing for imaging at least one light source or an object irradiated by the light source with at least one imaging device;
A signal is acquired from the imaging device every predetermined scanning plane period, a time average of the signal level difference is obtained from a signal level difference of the signal between a plurality of different scanning planes, and a predetermined average is obtained based on the time average value. Analysis processing for performing calculation processing, and
A determination process for performing a detection determination process by detecting and determining the state of the light source or the subject based on the analysis result of the analysis process;
At least in the state of the detection range each has various attribute information, state storage processing to store the information including the state change of the attribute in the state storage unit,
From the detection information obtained in the determination process, the position and size of the subject in all the images are searched to determine the position of the subject including the detection range, and the detection information including the detection range related to the subject is acquired. Subject position determination processing for storing detection information in the position storage unit as information on the position,
In the above analysis process,
When the detection information is stored in the position storage unit, including a process of selectively performing the analysis process on the image of the detection position range specified in the detection information,
In the above determination process,
A response speed value located in a predetermined range of the image specified by the position storage unit included in the information specifying the light source or the subject and the attribute information is acquired, and the detection time is determined from the detected response speed value of the acquired position. A program for causing a computer to execute signal processing of a detection system, including processing for performing detection determination processing at a response speed suitable for the position.

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