KR20120067578A - Apparatus and method for deciding day and night using parameter of camera - Google Patents

Abstract

PURPOSE: A day/night time decision device using parameter of a camera and a method thereof are provided to day/night time information using the control parameter which is stored in register of the camera. CONSTITUTION: A method of a day/night time decision device using parameter of a camera comprises the following steps: a camera module(110) takes a photograph of image; an object recognition program is installed in a recognition unit(130); a day/night time decision unit(120) detects change information according to brightness of photographing object and change information according to presence of light from register of the camera module; and a day/night time decision unit decides one of daytime, night time, and sunset which is decided in advance according to analyzed result of the change information. The object recognition program includes daytime recognition algorism and night time recognition algorism for recognizing objects.

Description

Day and night judgment device and method using camera parameters {APPARATUS AND METHOD FOR DECIDING DAY AND NIGHT USING PARAMETER OF CAMERA}

The present invention relates to a day / night judgment using a parameter of a camera. More particularly, the present invention relates to at least one of a day recognition algorithm or a night recognition algorithm by judging day, night and night using control parameters extracted from a register of a camera installed in a vehicle. An apparatus and method for day / night judgment using a camera parameter to allow one to be selected.

The most important thing when driving a vehicle is the prevention of safety driving and traffic accidents. To this end, various auxiliary devices for controlling the vehicle's running properly and controlling the functions of the vehicle components, and safety devices such as seat belts and air bags are provided. It is mounted on the vehicle.

In particular, when changing lanes while driving, collision accidents are frequently issued due to lack of awareness of distance and relative speed of the vehicle approaching from the rear, and recent vehicles detect other vehicles approaching from the rear of the vehicle. There is a rear alarm system.

Such a rear alarm device detects a vehicle by photographing another vehicle driving or approaching a blind spot where the driver cannot observe through an outside mirror installed outside the vehicle, and analyzing the result using an image recognition algorithm (program). It is configured to inform the driver of the existence of another vehicle when changing lanes.

On the other hand, the image recognition algorithm is a program that analyzes and recognizes the shape of the vehicle from the image information captured by the camera, the algorithm for recognizing the vehicle during the day and the algorithm for recognizing the vehicle at night to improve the recognition rate do.

In addition, whether to apply a daytime recognition algorithm or a nighttime recognition algorithm is determined by determining whether it is a daytime or a nighttime situation, and mainly determines the daytime or nighttime by extracting the brightness and lighting parameters of the image from the captured image information. do.

However, the method of determining day / night using image information based on brightness and illumination of the image has the following problems.

First, there is a problem that the night recognition algorithm is applied when the image information is input in the state of daytime but the vehicle is located under the dark bridge and is determined at night.

Secondly, if the dark screen is input due to a bush or a tree at the top of the captured image screen, it is determined that it is night, and there is a problem in that a night recognition algorithm is applied according to wrong day / night time determination information.

Third, if the bright screen is input due to the bright light of the surrounding buildings, it is determined that it is daytime and there is a problem in that the daytime recognition algorithm is applied by the wrong daytime / nighttime judgment.

Fourth, when judging the image information of a vehicle that lights a lighting device including a headlight and a vehicle that is not lit due to a twilight situation, when the ambiguous image is input, the correct day / night judgment information cannot be provided. There is a problem that unrecognition or misunderstanding occurs due to the application of the wrong recognition algorithm.

Fifth, the day / night judgment based on the image information has a problem that the information loss of the image data due to the image preprocessing of the camera occurs, it does not work properly in the uncertainty of the image, such as tunnels, bridges, surrounding background.

In order to solve this problem, the present invention is a daytime using a camera parameter to determine at least one of the daytime recognition algorithm or nighttime recognition algorithm by judging daytime, nighttime, and night life through the control parameters extracted from the register of the camera installed in the vehicle It aims at providing the night judgment apparatus and method.

In order to achieve the above object, the present invention is a day / night determination device using the parameters of the camera,

The change information according to the presence or absence of light and the change information according to the brightness of the photographing target are detected and analyzed from the register of the camera module which captures the image, and any one of the preset daytime, nighttime, and nightfall (at sunset) is determined according to the analysis result. It is characterized in that it comprises a day / night determination unit to provide a judgment information for applying the day / night algorithm of the recognition program to recognize the object by classifying the state.

In addition, the day / night determination unit according to the present invention communicates with the camera module AGC detector for detecting an AGC (Auto Gain Control) value that changes depending on the presence of light from the register of the camera module; An AEC detection unit communicating with the camera module to detect an auto exposure control (AEC) value that changes according to the brightness of a photographing target from a register of the camera module; The AGC value and the AEC value detected by the AGC detection unit and the AEC detection unit are calculated, and the result values are compared with reference values for determining the preset day, night, and fatality, and the day, night, and fatality are determined according to the result. A parameter analyzer which accumulates and calculates a situation parameter value by a predetermined size to be accumulated; And detecting a maximum value among cumulative situation parameter values calculated from the parameter analyzer to determine one of daytime, nighttime, and twilight, and compare the determined state with the previous state according to the result of a daytime recognition algorithm or nighttime. And a state determination unit for outputting an operation control signal to operate the recognition algorithms or to operate both the day / night recognition algorithms.

In addition, the state determination unit according to the present invention outputs a control signal such that both the daytime recognition algorithm and the nighttime recognition algorithm are operated when the previous state is the daytime state and the state determined according to the maximum value of the cumulative situation parameter value is the night state or vice versa. Characterized in that.

In addition, the state determination unit according to the present invention is characterized in that to maintain more than a predetermined time when both the day and night recognition algorithms operate.

In addition, the present invention is a day / night determination method using a camera parameter,

a) when the image information is input from the camera module, the day / night determination unit communicating with the camera module to detect a control parameter from the register of the camera module; b) a criterion for the day / night determination unit analyzing the control parameter detected in the step a) to store a predetermined specific parameter, and calculating the specific parameter to determine the preset day, night and night Contrast with values; c) accumulating and calculating the day / night determination unit by increasing a value of any one of the daytime parameter, the nighttime parameter, and the fatality situation parameter by a predetermined size according to the comparison result of step b); d) determining, by the day / night judgment unit, any one of day, night and night conditions according to the situation parameter value having the maximum value among the day, night and night situation parameters calculated in step c); And e) controlling the daytime / nighttime recognition algorithm to operate the daytime recognition algorithm or the nighttime recognition algorithm, respectively, or to operate both the daytime / nighttime recognition algorithm according to the result in contrast with the state determined in step d) and the previous state. And outputting a signal.

In addition, the specific parameter of step b) according to the present invention is characterized in that the AGC (Auto Gain Control) that changes depending on the presence of light and AEC (Auto Exposure Control) that changes depending on the brightness of the shooting target.

In addition, the step of cumulatively increasing the situation parameter value of the step c) according to the present invention by a predetermined size may be such that the weekly situation parameter value is cumulatively increased if the calculation result value of the specific parameter is less than or equal to a preset first reference value for weekly determination. If the calculation result value of the specific parameter is greater than or equal to the second reference value for night determination, the night situation parameter value is cumulatively increased. The cumulative situation parameter value is characterized in that the cumulative increase.

In addition, the step e) according to the present invention is a state in which the previous state is a day state and the state determined according to the maximum value of the accumulated situation parameter value is a night state or the previous state is a night state and the state determined according to the maximum value of the accumulated situation parameter value In the daytime state, both the daytime recognition algorithm and the nighttime recognition algorithm are characterized in that the operation.

In addition, the step e) according to the present invention is characterized in that only the night recognition algorithm is operated when the previous state is a night state or a twilight state and the state determined according to the maximum value of the accumulated situation parameter value is a night state.

In addition, the step e) according to the present invention is characterized in that only the weekly recognition algorithm is operated when the previous state is the daytime or the fatal state and the state determined according to the maximum value of the accumulated situation parameter value is the daytime state.

According to the present invention, by providing day / night information using control parameters stored in a register of a camera, the day / night recognition algorithm has an advantage of preventing a determination error due to background and weather.

In addition, the present invention has the advantage that it is possible to exclude the information loss of the image data due to the image pre-processing of the camera because of the control parameters of the camera.

In addition, the present invention has the advantage that it is possible to exclude the influence of the uncertainty of the image, such as tunnels, bridges, surrounding background.

In addition, the present invention has the advantage that it is possible to improve the recognition rate of the object recognition algorithm by clearly determining the day, night, and twilight according to the change of time and providing the result to the object recognition algorithm.

1 is a block diagram schematically illustrating an object recognition system to which a day / night judgment device using a parameter of a camera according to the present invention is applied.
Figure 2 is a block diagram showing the configuration of the day / night determination unit of the day / night determination device using the parameters of the camera according to the present invention.
3 is a flowchart illustrating a day / night determination process using a parameter of a camera according to the present invention;
4 is a flowchart illustrating the operation of a recognition algorithm according to a previous state and a current state in day / night determination using the parameters of the camera according to FIG. 3.
FIG. 5 is a flowchart illustrating an operation of a recognition algorithm according to a previous state and a current state in day / night determination using a parameter of a camera according to FIG. 4.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the day and night determination apparatus and method using the parameters of the camera according to the present invention.

1 is a block diagram schematically illustrating an object recognition system to which a day / night determination device using a camera parameter according to the present invention is applied, and FIG. 2 is a day / night determination device of a day / night determination device using a camera parameter according to the present invention. It is a block diagram which shows the structure of a night judgment part.

1 and 2, the day / night determination unit 120 using the control parameter of the camera according to the present invention is a configuration that is applied to the object recognition system 100 installed in a vehicle, a camera for taking an image It is installed between the module 110 and the recognition unit 130 installed with an object recognition program including a day recognition algorithm and a night recognition algorithm to recognize the object, and analyzes the control parameter information stored in the register of the camera, and according to the result It provides to the recognition unit 130, any one of the state, night and twilight.

The camera module 110 receives an image sensor that receives light and converts it into an electrical signal, and a lens module that collects or emits light from an object and causes an optical image to form on the image sensor, and light other than visible light for correct color reproduction. The package includes an IR-filter for removing a shape, a package for providing an appearance, and a camera controller for controlling the overall operation of the camera module, wherein the electric signal converted from the image sensor, that is, the image information is a day / night determination unit 120. Through the recognition unit 130 to be provided.

In addition, the camera module 110 controls the sensitivity of the image sensor based on the AGC (Auto Gain Control) control parameter to adjust the sensitivity of the image sensor according to the presence or absence of light based on the dark part of the object to be photographed, and the image according to the brightness of the object to be photographed. Auto Exposure Control (AEC) control parameters that control how long the sensor receives light are stored in registers built into the camera module.

In addition, the image sensor may be either CMOS or CCD, and any sensor may be used for the day / night judgment apparatus according to the present invention.

The day / night determination unit 120 detects the AGC and AEC control parameters stored in the register of the camera module 110 to analyze the change information according to the presence or absence of light and the change information according to the brightness of the photographing target, and the analysis thereof. According to the result, it determines a state of the day, night and night, which is set in advance, and provides it as decision information for applying the day / night algorithm of the recognition program that recognizes the object from the image information input from the camera. 121), an AEC detector 122, a parameter analyzer 123, and a state determiner 124.

Here, Myeong Myung refers to a state where the sky is dimly lit before sunrise and after sunset.

The AGC detector 121 communicates with the camera module 110 and detects an AGC (Auto Gain Control) value for adjusting the sensitivity of the image sensor based on a dark part of the photographing object as a control parameter stored in the register of the camera module 110. do.

The AGC is applied to determine day, night and twilight because control parameters change depending on the presence or absence of light. In the case of a camera, the AGC of daytime situation has a value of 0 to 1.5, and the AGC of night situation is 5 (where ' 5 'is the maximum value of the user-specified gain), and AGC in the twilight situation varies between 0 and 5 because the presence of light is irregular.

The AEC detection unit 122 is a control parameter stored in the register of the camera module in communication with the camera module 110, and adjusts the AEC (Auto Exposure Control) value for adjusting the time that the image sensor receives light according to the brightness of the photographing target. Is detected.

The AEC is applied to determine daytime, nighttime, and twilight because the control parameter changes according to the brightness of the image. In the case of a camera, the AEC of the daytime situation has the minimum value, the AEC of the nighttime situation has the maximum value, and the AEC of the twilight situation has the maximum value. Since the image brightness is irregular, it has a value that varies between the minimum and maximum values.

The parameter analyzer 123 is a determination variable for determining day / night, and multiplies the AGC value and the AEC value detected by the AGC detector 121 and the AEC detector 122, respectively, and the result value (the judgment variable). ) Is compared with reference values for judging preset day, night and night.

The arithmetic size of the result of multiplying the AGC value and the AEC value is changed between 0 and 10, and the flow conditions of day, night, and twilight can be defined as parameter values to check the state change.

In addition, the parameter analysis unit 123 accumulates and calculates a situation parameter value for determining the change of the day, night and night life by a predetermined size according to the value of the determination variable for determining day, night and night life. to provide.

That is, if the result of the multiplication operation (hereinafter, referred to as the judgment variable) is less than or equal to the first reference value for judging the daytime state, the daytime situation parameter value is increased by a certain amount, and the nighttime and nightly situation parameter value is decreased by a certain amount. Calculate cumulatively.

In addition, if the determination variable is greater than or equal to the second reference value for determining the night state, the night situation parameter value is increased by a certain size, and the daytime and night situation parameter values are reduced by a certain amount and then cumulatively calculated.

In addition, if the determination variable is a range between the first reference value and the second reference value, the fatal situation parameter value is increased by a certain size, and the day and night situation parameter value is reduced by a certain amount and then cumulatively calculated.

The situation parameter value is described by way of example, and has a value between the initial value '0' and the maximum value according to the user's setting, and the one-time change range changes by +/- '1' according to the determination variable. The cumulative calculation of the situation parameter values is as follows.

When the determination variable is 0 to 1, the value of the daytime situation parameter increases by +1 and the value of the night / night situation parameter decreases by -1 because it is less than the first reference value.

When the determination variable is 1 to 8, since the value is between the first reference value and the second reference value, the fatality situation parameter value is increased by +1, and the day / night situation parameter value is decreased by -1.

When the determination variable is 8 to 10, the value of the night situation parameter increases by +1 and the day / night situation parameter value decreases by -1 since the value is equal to or greater than the second reference value.

The state determiner 124 detects a situation parameter value having a maximum value among the cumulative situation parameter values calculated from the parameter analyzer 123, and determines that the situation parameter having the maximum value is a weekly situation parameter and is a daytime situation. If it is a parameter, it is decided to be night, and if it is a fatal situation parameter, it is determined to be night.

In addition, the state determiner 124 outputs a control signal or operates the day / night recognition algorithm so that the day recognition algorithm or the night recognition algorithm is operated according to the result of comparing the determined current state with the previous state. Output control signal along with day / night judgment signal.

That is, the state determiner 124 determines the day or night, and outputs a signal so that the recognizer 130 performs a recognition operation using a day recognition algorithm or a recognition operation using a night recognition algorithm, and before or after sunset. If it is in the dim state, it outputs a signal so that both the day recognition algorithm and the night recognition algorithm are operated.

In addition, the state determination unit 124 determines the day, night and twilight based on the maximum value of the situation parameter values for day / night judgment, and in addition to the day, night and twilight conditions, the tunnel section, the bridge, the underpass, the shadow of the building In case of temporarily passing through a dark area such as an area, or when a light or other light source of a nearby building is introduced, a forced fatal state is added in consideration of the recognition rate of the headlights on / off.

In other words, the state of time changes from day to day-> night (after sunset)-> night, or night-> night (before sunrise)-> day, but from day to night-> night or night-> day If the direct state changes, it is not recognized as a night or day state, and it is forced to maintain the fatal state for a preset time (for example, 1 minute).

Therefore, when the previous state is the daytime state and the determined state is the night state, or vice versa, the previous state is the night state and the determined state is the daytime state, the control signal such that both the daytime recognition algorithm and the nighttime recognition algorithm are operated in the recognition unit 130. Outputs the recognition rate of the recognition program to be improved.

3 is a flowchart illustrating a day / night determination process using a parameter of a camera according to the present invention, and FIGS. 4 and 5 illustrate recognition according to a previous state and a current state in day / night determination using a parameter of a camera according to FIG. 3. A flowchart illustrating the operation of the algorithm.

1 to 5 will be described in more detail the day / night determination method using the parameters of the camera according to the present invention.

When image information is input from the camera module 110, the day / night determination unit 120 communicates with the camera module 110 to detect a control parameter from the register of the camera (S100).

The main parameters of the camera module 110 are AGC (Auto Gain Control), AEC (Auto Exposure Control), AWB (Auto White Balnce), HDR (High Dynamic Range) mode selection, RGB AEC, White or Black pixel count , Brightness average, and the like, and the control parameters detected in step S100 are AGC and AEC.

The day / night determination unit 120 analyzes the control parameter detected in the step S100 to store a predetermined specific parameter, for example, AGC and AEC (S200), and multiplies the AGC and AEC (S300). .

The AGC is applied to determine day, night and twilight because control parameters change depending on the presence or absence of light, and the AEC is applied to determine day, night and twilight because control parameters change according to image brightness.

The arithmetic size of the result of multiplying the AGC value and the AEC value is changed, for example, between 0 and 10, and the state change can be confirmed by defining the flow conditions of day, night, and thinning as parameter values.

The day / night determination unit 120 compares the determination variable calculated in step S300 with reference values for determining the preset day, night, and night life (S400).

In addition, the day / night determination unit 120 increases the value of the daytime situation parameter by a certain size if the determination variable is less than or equal to the first reference value for determining the daytime state, and decreases the value of the nighttime and nightly situation parameters by a certain amount. If the determination variable is greater than or equal to the second reference value for determining the night state, the night situation parameter value is increased by a certain amount, and the daytime and night situation parameter values are reduced by a certain amount, and then the cumulative calculation is performed (S510). If the determination variable is within the range between the first reference value and the second reference value, the fatal situation parameter value is increased by a predetermined size, and the day and night situation parameter value is reduced by a predetermined amount and then accumulated (S520).

After performing any one of the steps S500 to S520, the day / night determination unit 120 performs a maximum value among the day, night and night situation parameter values calculated after performing any one of the steps S500 to S520. Day, night and night life is determined by detecting the situation parameter value having a (S600).

In the step S600, if the situation parameter having the maximum value is a weekly situation parameter, the day / night determination unit 120 determines to be in a day state, and operates only the weekly recognition algorithm or the day / night algorithm is operated in comparison with the previous state. To be made (S700).

That is, the day / night determination unit 120 determines whether the previous state is daytime or nighttime when the state determined in the step S600 is daytime (S701), and determines that the light or other light sources of the surrounding buildings are caused by forced fatality at nighttime. Output the control signal to the recognition unit 130 so that both the day / night recognition algorithm is operated (S702), and only the weekly recognition algorithm is activated (S704) when the previous state is day or night (S703). do.

In addition, if the situation parameter having the maximum value in step S600 is a night situation parameter, the day / night determination unit 120 determines the night state, and operates only the night recognition algorithm in comparison with the previous state or the day / night algorithm is All are operated (S710).

That is, the day / night determination unit 120 determines whether the previous state is daytime or nighttime when the state determined in the step S600 is night (S711), and if it is daytime, it is determined that the passage passes through the tunnel section, the bridge, the underpass, etc. All the day / night recognition algorithm by the operation (S712), and if the previous state is night or night (S713) as a result of the determination in step S711 the control signal recognition unit 130 to operate only the night recognition algorithm (S714) Will output

In addition, if the situation parameter having the maximum value in step S600 is a twilight situation parameter, and the previous state is a twilight state, the day / night determination unit 120 determines that it is a twilight state and allows the day / night algorithm to be operated in operation S720. ).

Thus, by providing day / night information using control parameters stored in the register of the camera module, the recognition rate of the day / night recognition algorithm can be further improved.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. It can be understood that

100: object recognition system 110: camera module
120: day / night judgment unit 121: AGC detection unit
122: AEC detector 123: parameter analyzer
124: state determination unit 130: recognition unit

Claims (10)

Day / night judgment device using the parameters of the camera,
The change information according to the presence or absence of light and the change information according to the brightness of the photographing target are detected and analyzed from the register of the camera module which captures the image, and any one of the preset daytime, nighttime, and nightfall (at sunset) is determined according to the analysis result. Day / night determination apparatus using a parameter of the camera, characterized in that it comprises a day / night determination unit for determining the state of the object to provide the determination information for applying the day / night algorithm of the recognition program for recognizing the object. The method of claim 1,
Day / night determination unit AGC detection unit for communicating with the camera module to detect the AGC (Auto Gain Control) value that changes depending on the presence of light from the register of the camera module;
An AEC detection unit communicating with the camera module to detect an auto exposure control (AEC) value that changes according to the brightness of a photographing target from a register of the camera module;
The AGC value and the AEC value detected by the AGC detection unit and the AEC detection unit are calculated, and the result values are compared with reference values for determining the preset day, night, and fatality, and the day, night, and fatality are determined according to the result. A parameter analyzer which accumulates and calculates a situation parameter value by a predetermined size to be accumulated; And
Detects a maximum value among the cumulative situation parameter values calculated from the parameter analyzer to determine one of daytime, nighttime, and twilight, and compares the determined state and the previous state according to the result of the daytime recognition algorithm or nighttime recognition Day / night determination apparatus using a parameter of the camera, characterized in that it comprises a state determining unit for outputting an operation control signal to operate the algorithm or to operate both the day and night recognition algorithm. The method of claim 2,
The state determining unit outputs a control signal such that both the day recognition algorithm and the night recognition algorithm are operated when the previous state is the day state and the state determined according to the maximum value of the cumulative situation parameter value is the night state or vice versa. Day / night judgment device using the parameters of. The method of claim 3, wherein
The state determination unit is a day / night determination device using a parameter of the camera, characterized in that to maintain more than a predetermined time when both the day and night recognition algorithms operate. Day / night judgment method using the parameters of the camera,
a) when the image information is input from the camera module, the day / night determination unit communicating with the camera module to detect a control parameter from the register of the camera module;
b) a criterion for the day / night determination unit analyzing the control parameter detected in the step a) to store a predetermined specific parameter, and calculating the specific parameter to determine the preset day, night and night Contrast with values;
c) accumulating and calculating the day / night determination unit by increasing a value of any one of the daytime parameter, the nighttime parameter, and the fatality situation parameter by a predetermined size according to the comparison result of step b);
d) determining, by the day / night judgment unit, any one of day, night and night conditions according to the situation parameter value having the maximum value among the day, night and night situation parameters calculated in step c); And
e) an operation control signal for the day / night determination unit to operate the day recognition algorithm or the night recognition algorithm, or to operate both the day / night recognition algorithm according to the result in contrast with the state determined in the step d) and the previous state; Day / night determination method using the parameters of the camera comprising the step of outputting. The method of claim 5, wherein
The specific parameter of step b) is AGC (Auto Gain Control) which changes according to the presence or absence of light, and AEC (Auto Exposure Control) which changes according to the brightness of the shooting target. Night judgment method. The method of claim 5, wherein
Accumulating and increasing the situation parameter value of the step c) by a predetermined size causes the weekly situation parameter value to be cumulatively increased if the calculation result value of the specific parameter is less than or equal to a preset first reference value for weekly determination. If the calculation result value of is greater than or equal to the second reference value for night determination, the night situation parameter value is increased. If the calculation result value of the specific parameter is in a range between the first and second reference values, the fatal situation parameter value is accumulated. Day / night determination method using a parameter of the camera, characterized in that the increase. The method of claim 5, wherein
In step e), if the previous state is the daytime state and the state determined according to the maximum value of the accumulated situation parameter value is the night state or the previous state is the night state and the state determined according to the maximum value of the accumulated situation parameter value is the daytime state recognition Day / night determination method using the parameters of the camera, characterized in that both the algorithm and the night recognition algorithm is operated. The method of claim 5, wherein
The step (e) of the day / night determination method using a camera parameter, characterized in that only the night recognition algorithm is operated if the previous state is a night state or night state and the state determined according to the maximum value of the accumulated situation parameter value is a night state. The method of claim 5, wherein
The step (e) is a day / night determination method using a parameter of the camera, characterized in that only the weekly recognition algorithm is operated if the previous state is day or night state and the state determined according to the maximum value of the accumulated situation parameter value is a day state.

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