KR101712447B1 - How to set up a video camera module with optical signal analysis funtion using the image sensor - Google Patents

Abstract

The present invention suggests a method for improving sensing efficiency of a camera for improving sensing efficiency of a transmission light source, capable of precisely analyzing a change situation of an image shape and a floodlight image level of transmission light by matching a frame period of the camera with a transmission period of the transmission light of an infrared rays picked up in an image sensor without using a separate additional device like a synchronization circuit (synchronization module) or a communication cable when photographing the transmission light of a light transmitter by the image sensor of the camera, and an apparatus thereof.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method for improving a detection efficiency of a camera for improving a detection efficiency of a transmission light source,

The present invention relates to a moving picture camera in which reliability of security is improved by determining the presence or absence of transmission light of an optical transmitter (infrared detector) in a video signal (information) photographed by an image sensor of a camera, , When the transmission light of the optical transmitter is photographed by the image sensor of the moving picture camera, the transmission period of the transmission light picked up by the image sensor without using a separate additional device such as a communication cable or a synchronization circuit (synchronization module) It is possible to precisely analyze the change in the level of the projected light of the transmission light and the change of the image form by synchronizing the periods of the transmission light and to transmit data between the optical transmitter and the camera as well as the crossing of the abnormal object, To improve the detection efficiency of the transmission light source in order to grasp the actual situation such as the change of the environment And more particularly, to a method and an apparatus for improving the detection efficiency of a camera.

In general, a moving picture camera can be divided into a surveillance camera, a portable camera, and a broadcasting camera. Since they belong to a multimedia device for their use, they have to comply with the world standard. The monochrome camera is an EIA RS- Shall comply with the EIA RS-170A standard.

 These video cameras are used for various purposes such as process monitoring, intrusion monitoring, road monitoring, vehicle traffic investigation, bridge monitoring, water field monitoring, smoke monitoring, torture monitoring, and visible light communication.

Among the moving picture cameras described above, the present invention relates to a camera for processing and discriminating the above-mentioned transmission light using an image.

The conventional moving picture camera related to the present invention is a moving picture camera according to the present invention, which is disclosed in Patent Publication No. 1014892150000 (a combined infrared ray detection sensor using images, an operation method thereof, and an integrated management system for security facilities using the same), an infrared ray sensor using the image, Security facility integrated management system).

However, the above-mentioned known patent has a technical feature that the reliability of the security system is greatly improved by detecting image information and transmission light at the same time through the image sensor of the camera and judging presence or absence of transmission light in the image information. However, Since the transmission light transmission period of the infrared sensor has different characteristics from each manufacturer, when the transmission light is photographed through the image sensor, the transmission period of the transmission light and the frame period of the camera do not coincide with each other, there is a problem.

As a result, there is a problem that it is necessary to overcome the problem that the transmission period of the transmission light must be matched with the frame period of the camera in advance in implementing the above-mentioned patent due to the above problems.

The present invention has been devised to solve the above-described problems, and has been accomplished remarkably, and it is proposed through the present invention.

The present invention relates to a moving picture camera having an optical signal analyzing function using an image sensor, in which when a transmission light of an optical transmitter is photographed by an image sensor of a camera, And to provide a method and apparatus for improving the detection efficiency of a camera for improving the detection efficiency of a transmission light source capable of precisely analyzing a change situation of a level and an image type.

According to an aspect of the present invention, there is provided a camera apparatus for improving a detection efficiency of a transmission light source,

A pulse generator for generating a pulse of the light source; a driving unit for driving the light source generated by the light source generator; an optical transmitter for filtering the light source transmitted by the driving unit and transmitting a light source for transmitting the filtering light source; An optical transmitter including a driving unit and a power unit for supplying power to the optical transmitter unit,

And an image sensor for receiving the transmission light transmitted from the light transmission unit by the image sensor and discriminating information of the transmission light,

Wherein the optical transmitter further comprises a pulse controller for controlling a pulse of the light source and a transmission period generated in the pulse generator,

A light source image is received by the image sensor and emitted at a predetermined position for each frame, and the light source image is "101010" or " Quot; 111111 "form (see FIG. 4C). If it is aperiodic, the message " optical transmission failure " is transmitted to the central processing unit 107, 104) and outputting a current image frame to an image level extracting unit at the same time;

An image level extracting unit for reading the image level values of each pixel corresponding to the size of the predetermined light source existing in the frames transmitted from the frame analyzing unit and transmitting the image level values to the image level and average value calculating unit 104;

101010 "or" 111111 "type using the information of the frame type transmitted from the frame analyzing unit 102. In the case of the" 101010 "type, An image level and an average value calculation unit for arithmetically averaging the image level values, arithmetically averaging the image level values of two adjacent frames if the image level values are "111111 ", and outputting the data;

The data output from the image level and average value calculation unit 104 stores the time and image level values and the data determined as the final normal data by the central processing unit 107 in the memory, A data portion 105 for outputting data;

The image level and the image level values for each frame transmitted from the average value calculation unit 104 are arranged in a time axis and are compared with a normal data type or a data protocol table to convert data according to an internal protocol preliminarily agreed with the data protocol table, A data judging section (106) for transmitting the data to the processing section (107);

The final data of the data judging unit 106 is received and displayed as a character and is stored in the memory of the data storing unit 105 and simultaneously transmitted to the transmitting unit 108 and the data transmitted from the frame analyzing unit 102 The central processing unit 107 transmits a stop transmission command to the data determination unit 106 at the same time as the reception of the transmission error message and transmits the stop command to the data determination unit 106. When the " And;

If the communication state is bad and the data transmitted from the central processing unit 107 is transmitted to the control center, the controller or the server by wired / wireless, and receives various control signals, 107, and transmits the "optical transmission failure" message transmitted from the frame analyzing unit 102 to the transmission unit immediately upon reception, and at the same time transmits a stop instruction to the data judging unit 106, And a transmission unit 108 for transmitting an analysis procedure resume command if the message is not received.

A method of improving the detection efficiency of a camera for improving the efficiency of sensing optical signals transmitted according to the present invention is a method for improving a detection efficiency of a camera by controlling a transmission optical frequency of an optical transmitter through a pulse control unit of an optical transmitter, 15Hz, and the transmission light pulse is set to 63.99ms, which is 33.33ms (scanning time 30.66ms + vertical retrace time 2.67ms) of one frame time of the image frame, and the pulse width is " twice effective scan time + And the off time is set to 2.67 ms or less equal to the retrace time.

In the present invention, the transmission light output period is made to coincide with every twofold frame of the image, and the pulse is interrupted by "111, 110, 101, 100" or the like to recognize the transmission light as well as the address identification method And the period of the pulse is addressed by a digital code method).

The present invention is characterized in that the image sensing range setting range of the camera is limited to the size of the optical transmitter body manually or automatically so that the processing time of the processor can be quickly performed because the range of the image sensing area is set for the purpose of preventing backlight and metering and processing range.

According to the present invention, it is possible to process and process data of an optical signal received by an image sensor by matching the transmission light transmission period of the optical transmitter with the frame period of the camera, and precisely analyze the change of the light projection image level and image shape of the transmission light It is possible to reliably perform a motion picture camera having an optical signal analysis function using an image sensor.

In addition, since the transmission period of the infrared transmission light and the frame period of the camera coincide with each other without using a separate additional device such as a communication cable and a synchronization circuit or an apparatus, no additional cost is incurred.

In addition, according to the present invention, when the light emitting period of the near-infrared light source or the visible light source is matched with the image receiving period of the camera, the image brightness of the light source is kept constant. Therefore, regardless of visible light or non- It is possible to utilize the range of application of the moving picture camera variously according to the data processing or processing method as described above.

Also, since the brightness of each frame is constant for each frame, it is possible to detect and analyze the change of the image level with respect to time.

1 is a block diagram illustrating a configuration of a transmitter according to the present invention.
2 is a block diagram of a moving picture camera according to the present invention.
3 is a transmission time chart of a moving picture camera frame and a transmitter according to the present invention.
4 is a flow chart illustrating a light source signal analysis processing process through a moving picture camera of the present invention.

Hereinafter, a method and apparatus for improving the detection efficiency of a camera for improving the detection efficiency of a transmission light source according to the present invention will be described in detail with reference to the accompanying drawings.

As described above, since transmission periods of various transmission lights are not uniformly standardized, the transmission period of transmission light is manufactured and sold for each maker. Therefore, when the transmission light is photographed by the image sensor of the camera, the intermittently blinking Sometimes the phenomenon appears and sometimes the brightness changes.

This phenomenon is large in daytime and nighttime, and even when there are many changes in the surrounding environment.

Therefore, not only can a constant image level be maintained, but also data can not be processed, processed and analyzed. This is because the transmission period of the transmission light and the frame period of the camera do not coincide with each other, and the aperture value of the camera or the value of the electronic shutter varies depending on the daytime, nighttime and ambient illumination brightness.

 The world standard vertical synchronization frequency of a video camera is 60 Hz (color: 59.94 Hz) in the interlaced scan method, and the number of the screens is 60 fields per second.

Progressive digital video camera method is a progressive scanning method different from interlaced scanning method, so there is no field concept and 60 frames are applied.

Since the interlaced and progressive moving picture cameras of the present invention can be employed interchangeably through the conversion module, the interlaced moving picture camera will be described below.

1 and 2, the moving picture camera apparatus 100 according to the present invention includes an optical transmitter 10 for transmitting a light source, an image sensor (for example, a personal computer) 10 for picking up image information and picking up a light source of the optical transmitter 10 A frame analyzing unit 102, an image level extracting unit 103, an image level and an average value calculating unit 104, a data storing unit 105, a data determining unit 106, a central processing unit 107, (108).

The optical transmitter 13 is an optical transmitter such as an infrared sensor or an infrared sensor. The optical transmitter 13 of the optical transmitter 10 transmits a light source, . The present invention is described by specifying an optical transmitter as an infrared sensor.

The optical transmitter 13 includes a power unit 11, a pulse generator 15, a driver 12, an optical transmitter 13, and a pulse controller 14. As described above, the optical transmitter 13 of the infrared ray detector transmits the transmission optical pulse in a period of 1/15 seconds, which is twice the 1/30 second of the image frame period of the world standard standard of EIA RS-170, i.e., 15 frames per second Is set through the pulse control unit (14). The control of the pulse control section 14 is performed through an oscilloscope.

The transmission optical pulse ON time must be 65.39 ms or more through the pulse control unit 14, the transmission optical pulse OFF time is 1.27 ms or less, and the period is set to 33.3333 * 2 times = 66.6666? 66.667 ms or less. The reason for this will be described below.

The image sensor 101 is built in the moving picture camera 100 and has a function of picking up a transmission light source (hereinafter referred to as a "light source"). The minimum number of imaging elements (pixels) * 6 = 36 pixels.

In general, the number of image pixels that can be analyzed by the image analysis program (hereinafter referred to as an analysis module) is 4 * 4 = 16 pixels, but this may be due to uncertain factors.

The above-described image sensor 101 captures and receives the transmission light together with the image information as shown in FIG. 4 (see FIG. 4A), and transmits it to the frame analyzing unit 102 (see FIG. 4B).

The frame analyzing unit 102 is built in a moving picture camera. The frame analyzing unit 102 emits a light source image received by the image sensor 101 at a predetermined position for each frame, and the light source image is "101010 on-off-on-off "or" on-on-on-on " (101010 or 111111) of the frame is periodically transmitted to the image level and average value calculation unit 104. At the same time, the current image frame is transmitted to the central processing unit 107, (See D in Fig. 4) to the intra-image level extracting unit 103. [

The image level extracting unit 103 reads the image level values of the pixels corresponding to the size of the predetermined light source existing in the frames transmitted from the frame analyzing unit 102 and quantizes the image level values to obtain an image level and an average value calculating unit 104 ).

The image level and average value calculation unit 104 calculates an average value of image levels of frames of the type of "101010" or "111111" using the information of the frame type transmitted from the frame analyzing unit 102.

That is, in the case of the "101010" type, the image level values of two neighboring frames are calculated by arithmetic averaging. In the case of the "111111" type, the image level values of two adjacent frames are arithmetically averaged.

The data storage unit 105 stores the time and image level values of the data sent from the image level and average value calculation unit 104 and the data determined as the final normal data by the central processing unit 107 in the memory of the data unit 105 And outputs the requested data at the request of the central processing unit 107. [

As shown in FIG. 4E, the data determination unit 106 compares the image level values of each frame transmitted from the image level and the average value calculation unit 104 with the normal data type or data protocol table In case of data, the data is converted according to an internal protocol (refer to I in FIG. 4) agreed to in advance and transmitted to the central processing unit 107.

The central processing unit 107 receives the final data of the data determination unit 106 and displays it as a character and stores it in the memory of the data storage unit 105 (see H in FIG. 4) (See G in Fig. 4).

The central processing unit 107 is a processor equipped with a control algorithm and having an arithmetic function.

In addition, the " optical transmission failure " message transmitted from the frame analyzing unit 102 is transmitted to the transmitting unit immediately upon reception, and at the same time, transmits the stopping command to the data judging unit 106. [ If the " optical transmission failure " message is not received, an analysis procedure resume command is transmitted.

The transmission unit 108 transmits data transmitted from the central processing unit 107 to a control station, a control unit, or a server by wired / wireless, receives various control signals, and checks the communication status. If the communication status is poor, And transmits a storage command to the central processing unit 107. [

Hereinafter, an embodiment for matching the transmission light period and the frame period of the camera according to the present invention will be described with reference to FIGS. 3 and 4. FIG.

The transmission light period of the optical transmitter 10 (see FIG. 1) should be illuminated in accordance with the period of the vertical synchronization frequency of the moving picture camera so that the image level of the camera side can be extracted as well as the image level proportional to the transmission light output of the optical transmitter 10 have.

If the transmission light period is set to be the same as the field or frame period of the image frame, if the synchronization period is not correct, if the OFF period of the transmission light pulse is within the imaging position range of the transmission light within the image frame, Or only a part of the transmission light source is picked up.

Therefore, the present situation will continue unless a person artificially moves the position of the camera upward or downward.

Accordingly, the transmission light period is controlled by the pulse control unit 14 (see FIG. 1) to be two times (1/15 second), three times (1/10 second), 4 times (1 / 7.5sec), etc., so that it can be output selectively to the nose or the stomach, so that even if the transmission light starts from the time on the time axis and is projected, it can be output in one, two or three frames An image of transmission light can be picked up by the image sensor 101 (see Fig. 2) at a constant brightness and period.

In this case, when the transmission light period is doubled, that is, when the position of the transmission light is located at the uppermost position of the screen, since the image is picked up at the beginning of the image frame as shown in Fig. 1, Similarly, when the off period of the transmission light pulse of the optical transmitter is located at this position, only the image of the optical transmitter body is captured without the image of the transmission light in the image frame. That is, since there is no transmission optical image in the frame and the transmission optical image is displayed on the screen in the next frame, when the transmission optical pulse is twice the image frame, the transmission light source image appears in one image frame even in the worst case do.

Therefore, a transmission optical image appears in the form of "101010 " in a time period in which the transmission period of the transmission light is slightly delayed before the frame period (precisely, the scanning period from the start of frame to the position where the image is displayed) , The transmission period of the transmission light must be delayed in advance of the period of the frame or more than the period of the frame (exactly, the pulse-off time of the transmission light is the time range in which the transmission optical pick- out of the bc position).

In other words, it appears in the form of "1111111" in which the transmission optical image appears in every frame.

As a result, even if the video frame period and the transmission optical transmission pulse period are the same, if the synchronization does not match, an image appears repeatedly in the form of "101010-111111-101010"

Therefore, in the moving picture camera 100, the average value of the pair of frames appearing one frame is determined as the transmission light reception level, and in the case described later, the average value of the adjacent frame pairs is determined as the transmission light reception level. The same principle applies to the case of three-fold and four-fold cycles.

However, in reality, in the case of triple and quadruple periods, the transmission optical image has at least 20 frames or 22 frames, which is longer than 15 frames at the time of 2 ×, so that the discrimination power from disturbance light such as sunlight may be deteriorated Points should be considered.

For reference, a typical transmission light period of a conventional digital optical transmitter (infrared transmission / reception system) ranges from 5 to 15 ms.

The EIA RS-170 frame standard signal related time of the camera is as follows

[One line horizontal scanning time]

1/15750 sec = 63.492 占 퐏 = 1H (color 1/15734 = 63.556 占 퐏 = 1H)

[Total horizontal scanning time]

525H = 33.33ms (color 525H = 33.366ms) = time per frame

[Minimum vertical blanking time]

40H = 2.539 ms? 2.54 ms (color 40H = 2.542 ms? 2.54 ms)

Field blanking time 20H + Frame blanking time 20H = 40H

[Effective horizontal scanning time]

485H = 30.79ms (color 485H = 30.82ms)

Therefore, when the pulse period of the transmission light is set to be twice the frame period, the following calculation is made.

[Transmission pulse ON time]

33.33 + 32.06 = 65.39 ms

[Transmission pulse OFF time]

1.27 ms

Therefore, in order to improve the recognition rate of the image, the transmission light pulse ON time should be 65.39 ms or more and the transmission light pulse OFF time should be 1.27 ms or less so that the mutual cycle error can be reduced. The period should be 33.3333 * 2 times = 66.6666 ≒ 66.667ms or less.

The fluctuation cycle time of the shape of the imaging position in the frame of the transmission light due to the fine mutual cycle error will be as "one frame cycle time ÷ error time = frame cycle time".

In the progressive-mode video camera, since it is a 60-frame (60-field) method, a transmission optical pulse cycle is set at a 2-frame cycle through the pulse controller 14 (see FIG. 1).

The OFF portion of the infrared light pulse partially spans a time range (a range of bc in Fig. 3, e.g., 0.55 to 0.93 m / sec) in which the infrared light image is displayed on the frame from the initial start time (image edge position) If so, the image will appear blurred by the corresponding portion of the image that spans the normal value.

Therefore, in such a case, the brightness of the position frame is arithmetically averaged over two or more cycles, and the frame is discarded if the brightness is less than a predetermined value.

The present invention can be applied to any light source that can perform a blinking function in an image frame period, such as an LED, a tungsten lamp, or a halo lamp.

The specification of the infrared light emitter is not limited to that exemplified by the invention since the disclosed technology mainly uses an optical transmitter.

10: optical transmitter 11:
12: driving unit 13: optical transmission unit
14: Pulse control unit 100: Video camera
101: image sensor 102: frame analyzing unit
103: Video level extracting unit
104: image level and average value calculation unit 105: data storage unit
106: Data judging unit 107: Central processing unit
108:

Claims (5)

A method for improving a detection efficiency of a camera for improving a detection efficiency of a transmission light source in capturing a transmission optical image of an optical transmitter and converting it into an image level and analyzing the transmission optical image,
The period of the transmission light pulse through the pulse control unit of the optical transmitter is set to be equal to or greater than 1 times the frame period of the camera and the OFF time of the transmission light pulse is set to be equal to the frame vertical retrace time of the camera Setting,
The image level and average value calculation unit of the camera may display the transmission light source image captured by the camera in the form of "ON-ON-ON-ON" every frame if the transmission light period of the optical transmitter is one- Arithmetically averages transmission optical image level values of adjacent frame pairs or crosses one frame and arithmetic averages the transmission optical image level values of neighboring frame pairs when they appear in the form of "ON-OFF-ON-OFF" A method for improving the detection efficiency of a camera to improve the detection efficiency of a light source. The method according to claim 1,
The image level and the average value calculation unit may calculate the average and the average value of the transmission light source image in which the transmission light source image picked up by the moving picture camera in the odd number or the even number times larger than two times the frame period of the camera of the optical transmitter is less than one Wherein the average value of the transmission optical image levels of the adjacent pair of frames or the average value of the transmission optical image levels of the adjacent pair of frames is calculated by arithmetically averaging the transmission optical image level values of the adjacent pair of frames or crossing one frame, A method for improving the detection efficiency of a sensor. delete The method according to claim 1,
Wherein the image level and the average value calculation unit calculate the period of the transmission optical pulse of each optical transmitter by the address identification method. An optical transmitter including a pulse generator for generating a pulse of a light source, a driving unit for interrupting power in a pulse form and transmitting the pulse to the optical transmitter, and an optical transmitter as a light source; A camera device having an image sensor for capturing transmitted transmission light through an image sensor,
Wherein the optical transmitter further comprises a pulse controller for controlling a transmission period of a light source pulse generated in the pulse generator, wherein the optical transmitter comprises: an image sensor for capturing the transmission light and the image; 101010 "or" 111111 "in the two-times cycle of the image frame, and transmits a " light transmission failure " message to the central processing unit 107 if the light source periodically changes. A frame analyzer 102 for periodically transmitting the image format of the frame to the image level and average value calculator 104 and outputting the current image frame to the image level extractor 103 at the same time;
An image level extracting unit for reading the image level values of the pixels corresponding to the size of the predetermined light source existing in the frames transmitted from the frame analyzing unit 102 and digitizing the image level values and transmitting the image level values to the image level and average value calculating unit 104 103);
101010 "or" 111111 "type information using the information of the frame type transmitted from the frame analyzing unit 102. In the case of" 101010 ", two frames An image level and an average value calculation unit 104 for arithmetically averaging the image level values of two adjacent frames if the image level values are "111111"
The data output from the image level and average value calculation unit 104 stores the time and image level values and the data determined to be the final normal data by the central processing unit 107 in the memory, A data portion 105 for outputting the requested data;
The image level and the image level values for each frame transmitted from the average value calculation unit 104 are arranged in a time axis and are compared with a normal data type or a data protocol table to convert data according to a predetermined internal protocol A data judging unit 106 for transmitting the data to the central processing unit 107;
The final data of the data judging unit 106 is received and displayed as a character and stored in the memory of the data storing unit 105 and the data is transmitted to the transmitting unit 108 and the data transmitted from the frame analyzing unit 102, And transmits a stop command to the data judging unit 106 at the same time, and transmits an analysis procedure resume command if the " optical transmission error " message is not received, );
If the communication state is bad and the data transmitted from the central processing unit 107 is transmitted to the control center, the controller or the server by wired / wireless, and receives various control signals, 107, and transmits the "optical transmission failure" message transmitted from the frame analyzing unit 102 to the transmission unit immediately upon reception, and at the same time transmits a stop instruction to the data judging unit 106, And a transmission unit (108) for transmitting an analysis procedure resume command if the message is not received.

Images