KR101241803B1 - Multi-camera video recording device and method for vehicle using multi-camera system - Google Patents

Multi-camera video recording device and method for vehicle using multi-camera system Download PDF

Info

Publication number
KR101241803B1
KR101241803B1 KR1020100060703A KR20100060703A KR101241803B1 KR 101241803 B1 KR101241803 B1 KR 101241803B1 KR 1020100060703 A KR1020100060703 A KR 1020100060703A KR 20100060703 A KR20100060703 A KR 20100060703A KR 101241803 B1 KR101241803 B1 KR 101241803B1
Authority
KR
South Korea
Prior art keywords
image data
camera
image
brightness
cameras
Prior art date
Application number
KR1020100060703A
Other languages
Korean (ko)
Other versions
KR20120000373A (en
Inventor
고동형
Original Assignee
엠텍비젼 주식회사
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 엠텍비젼 주식회사 filed Critical 엠텍비젼 주식회사
Priority to KR1020100060703A priority Critical patent/KR101241803B1/en
Publication of KR20120000373A publication Critical patent/KR20120000373A/en
Application granted granted Critical
Publication of KR101241803B1 publication Critical patent/KR101241803B1/en

Links

Images

Landscapes

  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Studio Devices (AREA)
  • Signal Processing (AREA)
  • Mechanical Engineering (AREA)
  • Closed-Circuit Television Systems (AREA)

Abstract

The present invention relates to a vehicle video recording apparatus and method suitable for a black box mounted on a vehicle using a multi-camera. An image recording apparatus for a vehicle for capturing and storing an image of a vehicle surroundings includes: a plurality of cameras configured to have different exposure times and convert an external optical image into image data which is an electrical signal and output the image data; And a digital video recorder for analyzing brightness of image data input from each of the plurality of cameras, and selecting and storing image data having brightness capable of identifying a main subject. According to this, by using a multi-camera system composed of a plurality of cameras having different exposure time, by selecting and storing the recorded image with the minimum back light effect caused by the narrow dynamic range of one camera, the main subject such as a license plate The brightness of the can be ensured.

Description

Multi-camera video recording device and method for vehicle using multi-camera system}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle video recording apparatus and method, and more particularly, to a vehicle video recording apparatus and method suitable for a black box mounted on a vehicle using a multi-camera.

As automobiles become a necessity for life, side effects such as parking problems, traffic problems, and traffic accidents are increasing.

In particular, traffic accidents may be resolved smoothly by agreement between the parties, but if the judgment of negligence is ambiguous, agreement between the parties may not be easily achieved. .

Therefore, the necessity of handling traffic accidents based on objective data is urgently needed, and in consideration of such necessity, various methods that can be used as objective data when handling accidents by actually mounting a device such as a black box of an aircraft in a vehicle are developed. It is becoming.

A vehicle black box system (ie, a vehicle video recording apparatus) currently being developed mainly uses a camera to record and store image data of a vehicle around the vehicle. In addition, such a vehicle video recording apparatus may be connected to an external electronic device to check stored image data, and may include a liquid crystal display in order to check a type without a liquid crystal display and also allow the captured or stored image data to be checked through the corresponding device. Type and the like.

Such an image recording apparatus for a vehicle may provide objective data of determining responsibility for accidents by storing images before and after an accident occurs.

1 is a block diagram of a conventional vehicle video recording apparatus, and FIG. 2 is a flowchart of a method for acquiring a recorded image having an appropriate brightness in a conventional vehicle video recording apparatus, and FIG. 3 is a flowchart of a recorded image before and after exposure compensation. 4 is an exemplary diagram, and FIG. 4 is an exemplary diagram of a recorded image photographed in a special situation.

Referring to FIG. 1, a conventional video recording apparatus for a vehicle 1 includes a camera 2 for capturing an image of a vehicle and generating image data, and a digital video recorder for storing image data received from the camera 2. It includes (3).

The camera 2 automatically compensates for the exposure to meet changing lighting conditions around the vehicle. Referring to FIG. 2, the brightness value of all pixels is measured with respect to the image data photographed by the camera 2, and the overall brightness of the image is measured from the average (step S10), and compared with the preset reference brightness (step S10). Step S12). As a result of the comparison, if the brightness of the current image data is substantially the same as the reference brightness (including when the difference is within a specified error range), it is not necessary to change the exposure time preset in the camera 2 so that the setting of the camera 2 is changed. If the brightness of the current image data is darker than the reference brightness (step S14), the setting of the camera 2 is controlled to increase the exposure time (step S16), and the brightness of the current image data is brighter than the reference brightness. In this case, the setting of the camera 2 is controlled to reduce the exposure time (step S18).

For example, as shown in FIG. 3, the subject is darkly photographed before the exposure compensation, and the subject cannot be identified, but after the exposure compensation set to increase the exposure time, the subject is photographed to have the appropriate brightness to identify the subject. .

However, in this case, it is impossible to photograph the image before the exposure compensation, so a gap occurs due to parallax, and there is a problem that even a very short moment of image loses important information in a sudden situation such as an important vehicle accident.

In addition, in the conventional vehicle video recording apparatus, the overall brightness is the same, but there is a limit that the brightness of the main subject may vary according to the distribution of the light source. For example, in a special situation such as that shown in FIG. 4 ((a) is for outdoor backlighting, (b) is for indoor parking, and (c) is taken with night headlights) indoor / outdoor and / or In addition, there is a problem that the brightness of the main subject such as a license plate to be recorded in the vehicle video recording device due to the backlight effect in the day and night is not enough.

The above-described background technology is technical information that the inventor holds for the derivation of the present invention or acquired in the process of deriving the present invention, and can not necessarily be a known technology disclosed to the general public prior to the filing of the present invention.

The present invention uses a multi-camera system composed of a plurality of cameras having different exposure time to select and store a recording image of the back light effect is minimized due to the narrow dynamic range of one camera to store the license plate To provide a vehicle video recording apparatus and method using a multi-camera system to ensure the brightness for the shooting of the main subject, such as.

In addition, the present invention is to provide a video recording apparatus and method for a vehicle using a multi-camera system to minimize the loss of information due to the appropriate exposure error under various circumstances, and to record important information even in a sudden situation.

In addition, the present invention is to use a multi-camera system using a multi-camera system exhibiting a similar power consumption than when using a single camera by reducing the unnecessary power consumption by turning off the operating power of the remaining cameras except for the selected camera at a certain period while using the multi-camera system An image recording apparatus and method are provided.

Other objects of the present invention will be readily understood through the following description.

According to an aspect of the present invention, a vehicle image recording apparatus for recording and storing an image of the surrounding vehicle, it is set to have a different exposure time, a plurality of output to convert the external optical image to the image data which is an electrical signal and output camera; And a digital video recorder that analyzes brightness of image data input from each of the plurality of cameras and selects and stores image data satisfying a preset brightness condition to identify a main subject. An image recording apparatus is provided.

The digital video recorder may include an image analyzer configured to perform a histogram analysis on the image data; A camera selector which selects a camera which outputs image data satisfying the preset brightness condition based on a result of the histogram analysis; The image storage unit may store an image data output from the selected camera.

The camera selector may select a camera that outputs the image data having the smallest deviation through a normality test calculating a deviation between the brightness distribution curve and the normal distribution curve of the image data according to the histogram analysis.

Alternatively, the camera selector may select a camera by using a bias value indicating a degree of shift of the brightness distribution curve of the image data according to the histogram analysis. The bias value is a distance from the center of the brightness value expressible in the image data to the center line of the main lobe of the brightness distribution curve, and the camera selector outputs the image data having the smallest absolute value of the distance. You can select a camera.

The image analyzer may perform histogram analysis on an area specified individually among images input by each camera.

The camera controller may further include a camera controller configured to generate and output a first camera control signal for turning off the operation power for a predetermined time to a camera other than the camera selected by the camera selector among the plurality of cameras. have.

The camera controller may generate and output a second camera control signal for turning on the operating power of the camera in the standby state after the predetermined time has elapsed.

The plurality of cameras may start capturing images at the same time.

On the other hand, according to another aspect of the present invention, a vehicle image recording apparatus for recording and storing the image around the vehicle, it is set to have a different exposure time to convert the external optical image to the image data which is an electrical signal and output A plurality of cameras; And a digital video recorder for storing all image data input from each of the plurality of cameras.

The digital video recorder may analyze brightness of image data input and stored from each camera and may delete remaining image data except for image data satisfying a preset brightness condition to identify a main subject.

The digital video recorder may include: an image storage unit which stores all image data input from the plurality of cameras; An image analyzer for performing a histogram analysis on the image data; An image selecting unit which selects image data satisfying the preset brightness condition based on a result of the histogram analysis; The image deleting unit may delete an image data other than the image data selected by the image selecting unit.

The image selector may select image data having the smallest deviation through normality verification that calculates a deviation between the brightness distribution curve and the normal distribution curve of the image data according to the histogram analysis.

Alternatively, the image selector may select image data by using a bias value indicating a deviation degree of the brightness distribution curve of the image data according to the histogram analysis. The bias value is a distance from the center of the brightness value expressible in the image data to the center line of the main lobe of the brightness distribution curve, and the image selector may select the image data having the smallest absolute value of the distance.

The image analyzer may perform histogram analysis on an area specified individually among images input by each camera.

The plurality of cameras may start capturing images at the same time.

On the other hand, according to another aspect of the present invention, there is provided a method for recording an image around the vehicle in a vehicle image recording apparatus including a plurality of cameras and a recording medium in which a program for performing the same is recorded.

According to one or more exemplary embodiments, an image recording method includes: (a) receiving image data photographed by the plurality of cameras and analyzing brightness, wherein the plurality of cameras are set to have different exposure times; (b) selecting a camera photographing image data that satisfies a predetermined brightness condition to identify a main subject according to an analysis result; And (c) storing image data photographed by the camera selected in step (b).

In the step (a), the brightness of the image data may be analyzed by histogram analysis.

In step (b), a camera which outputs the image data having the smallest deviation may be selected through normality verification that calculates a deviation between the brightness distribution curve and the normal distribution curve of the image data according to the histogram analysis.

In the step (b), the camera may be selected using a bias value indicating the degree of shift of the brightness distribution curve of the image data according to the histogram analysis. The bias value is a distance from the center of the brightness value that can be expressed in the image data to the center line of the main lobe of the brightness distribution curve, and the camera outputting the image data having the smallest absolute value of the distance in step (b). You can choose.

In the above step (a), the histogram analysis may be performed only on an individually designated area among the images input by each camera.

The method may further include generating and outputting a first camera control signal for turning off the operation power for a predetermined time for a camera other than the camera selected in the step (b) among the plurality of cameras. .

The method may further include generating and outputting a second camera control signal for turning on the operating power of the camera in the standby state after the predetermined time has elapsed.

According to another embodiment, an image recording method includes: (a) storing all image data input from each of the plurality of cameras, wherein the plurality of cameras are set to have different exposure times; (b) analyzing the brightness of the stored image data; And (c) deleting the remaining image data except for image data that satisfies a preset brightness condition so that the main subject can be identified according to the analysis result.

In the step (c), it is possible to delete the remaining image data except the image data having the smallest deviation through normality verification, which calculates a deviation between the brightness distribution curve and the normal distribution curve of the image data according to the histogram analysis.

In the step (c), the image data satisfying the preset brightness condition may be selected using a bias value indicating a shift degree of the brightness distribution curve of the image data according to the histogram analysis. The bias value is a distance from the center of the brightness value that can be expressed in the image data to the center line of the main lobe of the brightness distribution curve, and the remaining image data except the image data having the smallest absolute value of the distance in step (c). Can be deleted.

In the step (b), the histogram analysis may be performed only on an individually designated area of the image input by each camera.

The plurality of cameras may start capturing images at the same time.

Other aspects, features, and advantages will become apparent from the following drawings, claims, and detailed description of the invention.

According to an embodiment of the present invention, by using a multi-camera system composed of a plurality of cameras having different exposure time, by selecting and storing a recorded image of the backlight effect is minimized due to the narrow dynamic range of one camera Brightness can be ensured for shooting of a main subject such as a license plate.

In addition, under various circumstances, information loss due to appropriate exposure errors can be minimized, and important information can be recorded even in a sudden situation.

In addition, while using a multi-camera system, power consumption of the remaining cameras other than the selected camera is turned off at regular intervals, thereby reducing unnecessary power consumption, thereby exhibiting power consumption similar to that of using one camera.

1 is a block diagram of a conventional video recording apparatus for a vehicle.
2 is a flowchart of a method for acquiring a recorded image having appropriate brightness in a conventional vehicle video recording apparatus.
3 is an exemplary diagram of a recorded image before and after exposure compensation.
4 is an exemplary view of a recorded image photographed in a special situation.
5 is a block diagram illustrating a vehicle video recording apparatus using a multi-camera system according to an embodiment of the present invention.
6 is an exemplary view of image analysis on a captured image.
7 is an exemplary diagram of image data photographed by a plurality of cameras having different exposure times in a multi-camera system used in a vehicle image recording apparatus according to an embodiment of the present invention.
8 is a flow chart of a method for recording an image using a multi-camera system in a vehicle image recording apparatus according to an embodiment of the present invention.
9 is a block diagram of a vehicle video recording apparatus using a multi-camera system according to another embodiment of the present invention.
10 is a flowchart of a method of recording an image using a multi-camera system in a vehicle image recording apparatus according to another embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and described in detail in the detailed description. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, the terms "comprises" or "having" and the like refer to the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Also, the terms " part, "" module," and the like, which are described in the specification, refer to a unit for processing at least one function or operation, and may be implemented by hardware or software or a combination of hardware and software.

In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

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

5 is a block diagram illustrating a video recording apparatus for a vehicle using a multi-camera system according to an exemplary embodiment of the present invention, and FIG. 6 is an exemplary diagram of image analysis of a captured image.

The vehicle image recording apparatus 100 using the multi-camera system according to the present embodiment uses a plurality of cameras 110-1, 110-2,..., 110-n, hereinafter referred to as '110'. While photographing, the exposure time is set differently to obtain a plurality of image data having different brightnesses, and store all or one or more selected image data.

Therefore, according to the present exemplary embodiment, image data having various exposure times at the same time can be obtained with respect to a predetermined area including a main subject, so that when one camera is used, dark or overexposure due to underexposure is caused. The saturation phenomenon solves the problem of not being able to identify a main subject such as a license plate. In addition, under various circumstances (e.g., outdoor backlighting, indoor parking lot, night headlights, etc.), information loss due to an appropriate exposure error is minimized, and important information is recorded even in a sudden situation. There is an effect of maximizing the function of the video recording device, especially the vehicle black box system.

Referring to FIG. 5, an image recording apparatus for a vehicle 100 using a multi-camera system according to an exemplary embodiment may include a plurality of cameras 110 mounted on a vehicle and photographing an image around a vehicle, and a plurality of cameras 110. It includes a digital video recorder 120 for receiving and storing the captured image.

The plurality of cameras 110 constitute a multi-camera system, and are basically set such that their exposure times are different from each other (t 1 ≠ t 2 ≠ ... ≠ t n ).

Each camera 110 is arranged so that most of the shooting areas can be superimposed on one another (for example, a plurality of cameras are disposed on the front of the vehicle video recording apparatus 100 to photograph the outside of the vehicle). A main subject (eg, a license plate of an opponent's vehicle, etc.) that is required may be located in an overlapping area so as to be photographed by a plurality of (eg, all) cameras 110.

In addition, each camera 110 is set to the same time to start shooting, so that the gap between the video data does not occur between each image data to minimize the loss of important information even in a sudden situation such as a car accident .

Each camera 110 may be set ON / OFF of the operating power according to a camera control signal transmitted from the digital video recorder 120 to be described later. When the operating power is turned on, it is converted into an active state to generate image data obtained by converting an external optical image into an electrical signal and provide the image data to the digital video recorder 120. The operating power is turned off. ) To the standby status to reduce power consumption.

The digital video recorder 120 receives image data from each of the plurality of cameras 110, analyzes each image data to measure its brightness, and stores image data having appropriate brightness.

The digital video recorder 120 includes an image analyzer 122, a camera selector 124, an image storage unit 126, and a program storage unit 130. According to an embodiment, the camera controller 128 may further include.

The image analyzer 122 performs a histogram analysis on the input image data. The histogram analysis is performed by calculating brightness of each pixel of the image data, counting the number of pixels having each brightness, and converting the result into a histogram.

Here, the histogram analysis may be performed on the entire area of the input image data, or the histogram analysis may be performed only on the partial area of the input image data.

As described above, the photographing areas photographed by the plurality of cameras 110 have areas overlapping each other, and the main subject is located in the overlapping area. Accordingly, it is more accurate to perform histogram analysis only on the overlapped areas where the main subjects are located with respect to the image data provided from each camera 110 and compare the analysis results with the camera selector 124 which will be described later. You may be able to select the camera you are shooting. In this case, the image analyzer 122 may know in advance which part of the overlap region is with respect to the image input from each camera.

An example of histogram analysis for various images is shown in FIG. 6. The horizontal axis represents brightness, and the vertical axis represents the number of pixels having the corresponding brightness.

The camera selector 124 selects image data that satisfies an appropriate brightness, that is, a brightness condition for identifying a main subject, based on the result analyzed by the image analyzer 122, and provides corresponding image data. One camera 110 is selected. The brightness condition that enables the identification of the main subject may be determined and set experimentally and / or statistically and may be changed by the user.

Methods for selecting image data having appropriate brightness may vary, but only a few embodiments are described below.

As a first embodiment, a method using a brightness distribution curve of image data according to histogram analysis may be applied. In general, when the brightness distribution curve of the image data is the same as or similar to the normal distribution curve, it can be seen that the image is captured at an appropriate exposure.

Therefore, the brightness distribution curve generated as a result of histogram analysis of the image data through the normality test with respect to the image data is compared with the normal distribution curve which forms a bell-shape which is symmetric with the average brightness as the center. At that time, the deviation is calculated and the video data with the smallest deviation is selected. As a result, image data having an appropriate brightness may be selected from the image data currently captured by the plurality of cameras 110.

As a second exemplary embodiment, a method of using a bias value indicating a degree of bias toward a specific brightness may be applied to select image data having an appropriate brightness. The bias value represents the degree to which the brightness distribution curve generated as a result of histogram analysis of the image data is left or right centered about the center of the horizontal axis of the coordinate axis (average value or median value of the minimum and maximum brightness of the image data). As a value, it can be the distance from the center to the centerline of the main lobe of the brightness distribution curve. The main lobe is a main area portion in which most data exists in the brightness distribution curve, and reference numerals 150a, 150b, 150c-1, 150c-2, and 150d in FIG. 6 correspond to this.

Assuming that the horizontal axis of the histogram increases in brightness from left to right, the main lobe of the distribution curve is skewed to the left in case of underexposure (see Fig. 6 (a)), so that the absolute value of the deviation value is large. In case of overexposure (refer to (b) of FIG. 6), it is biased on the right side, so that the bias value has a positive value with a large absolute value, and in the case of backlight (FIG. 6 (c)) is divided into both left and right ends so that the bias value has both a negative (-) value and a positive (+) value whose absolute value is large, and in the case of proper exposure (Fig. 6). In (d), it is located in the center without excessively biased left or right, so that the absolute value has a small absolute value.

Accordingly, by determining whether the exposure state of the corresponding image data corresponds to an underexposure, an overexposure, a backlight, or an appropriate exposure, the bias value corresponds to an appropriate exposure among the image data photographed by the plurality of cameras 110. Image data can be selected.

Alternatively, image data having an appropriate brightness may be selected by applying a method combining the first and second embodiments.

The image storage unit 126 stores image data provided from the camera selected by the camera selection unit 124 in a predetermined storage space. The predetermined storage space is a space for permanently storing image data, and may be, for example, a nonvolatile memory such as NAND FLASH, NOR FLASH, SD CARD, MMC CARD, or CF CARD.

In the present embodiment, the image data photographed by the plurality of cameras 110 may be a still image or a moving image. When the image data is a moving image, the frame rate of each image data may be the same or different according to the exposure time set in each camera 110. For example, when the exposure time of the first camera is 1 / 30s and the exposure time of the second camera is 1 / 90s, the highest frame rate of the image data photographed by the first camera is 30 fps (frame per second). In contrast, the highest frame rate of the image data photographed by the second camera may be 90 fps.

Therefore, when the image data to be stored is a moving image, the image storage unit 126 obtains information on the frame rate from the setting information of the selected camera and compares it with the frame rate of the previously stored image data or the default frame rate. The data rate may be converted and stored so that the frame rate of the finally stored image data matches the frame rate of the previous image data or the default frame rate for data matching with previously stored image data. Afterwards, the final stored image data is displayed on a display unit (not shown) provided in the vehicle image recording apparatus 100 or a display device connected to the vehicle image recording apparatus 100 by wire / wireless or finally received image data. When displayed through the device, it can be displayed as a continuous image without being unnatural.

The digital video recorder 120 may further include a camera controller 128 that generates and outputs a camera control signal for turning off the operation power for a predetermined time except for the camera selected by the camera selector 124. Can be.

If the camera selector 124 determines that the exposure is appropriate and one or more cameras are selected, having the photographing operation performed on the remaining cameras increases unnecessary power consumption. Accordingly, the camera controller 128 generates and outputs a camera control signal for turning off the operation power of the remaining unselected cameras, thereby reducing unnecessary power consumption. When used by the same portable power supply, the available time can be extended.

The camera controller 128 may generate and output a camera control signal for turning on the operating power so that the operating power is turned off and then activated for the camera in the standby state after a predetermined time elapses. . This means that even if the camera is selected before, after a certain time has elapsed, the situation outside the vehicle may change and it may not correspond to an appropriate exposure state. This is because it is necessary to update the information on the camera having a proper exposure by repeatedly performing.

The program storage unit 130 stores a program for driving the vehicle image recording apparatus 100. For example, software for allowing one or more components of the image analyzer 122, the camera selector 124, the image storage 126, the camera controller 128, and the like to operate may be provided in the program storage 130. Storage can be maintained. The program storage unit 130 may be a nonvolatile storage space.

FIG. 7 is an exemplary diagram of image data photographed by a plurality of cameras having different exposure times in a multi-camera system used in a vehicular image recording apparatus according to an embodiment of the present invention.

Referring to FIG. 7, an entire image photographed by a multi-camera system composed of a plurality of cameras having different exposure times T / 2, T, and 2T and a partial image of a main subject (here, a license plate of a counterpart vehicle) are illustrated. It is.

As such, the brightness of the entire image and the brightness of the main subject part image are different from each other according to the exposure time, and thus the possibility of identification is also different. As shown in the present invention, after obtaining as much image data according to various exposure times as possible, appropriate exposure is achieved. By selecting and storing the image data having a, it is possible to minimize the information loss due to the exposure error.

8 is a flowchart of a method of recording an image using a multi-camera system in a vehicle image recording apparatus according to an embodiment of the present invention. Each step described below may be performed by each internal component of the vehicular image recording apparatus.

In operation S200, the plurality of cameras converts and outputs an external optical image into image data which is an electrical signal.

Here, each camera is set to have a different exposure time. In addition, most of the photographing areas photographed by each camera are overlapped with each other so that the main subjects are located in the overlapping regions so that an image of the main subjects can be stored regardless of which camera is selected. In addition, each camera performs shooting at the same time so that no gap is generated between the image data even if any camera is selected.

In step S210, the image analyzer of the digital video recorder analyzes the brightness of the image data provided from each of the plurality of cameras. Histogram analysis can be used as a method for analyzing brightness. Here, the brightness analysis may be performed on the entire area of the image data, or the brightness analysis may be performed only on the overlapping area including the main subject.

In operation S220, the camera selector selects image data having appropriate brightness by using the result analyzed in operation S210, and selects a camera that provides the image data.

As a method for selecting image data having an appropriate brightness, a normality verification method for calculating and comparing deviations between the brightness distribution curve and the normal distribution curve of each image data, and calculating the bias value of the brightness distribution curve of each image data, There is a bias comparison method. The normality verification method and the bias value comparison method have been described in detail above, and thus description thereof will be omitted.

In operation S230, the image storage unit stores image data generated and output from the camera selected by the camera selection unit in a predetermined storage space. Here, when the image data is a moving image, the frame rate information may be obtained from the setting information of the camera, and may be converted and stored to have the same frame rate as the frame rate of the previously stored image data or the default frame rate.

According to an image recording method according to an embodiment, steps S200 to S230 may be repeatedly performed whenever image data is stored.

Alternatively, according to an image recording method according to another embodiment, step S225 may be additionally performed between steps S220 and S230.

In step S225, the camera selector turns off the operation power for a predetermined time to switch to the standby state except for the camera which provided the image data selected as having the proper brightness by the normality verification method or the bias value comparison method. The camera control signal can be generated and transmitted. This allows the limited battery capacity to be utilized efficiently by reducing power consumption by the remaining cameras for a period of time.

After step S230, step S230 is repeated until a predetermined time elapses, and after a predetermined time elapses, the operation power is turned on for the remaining cameras in the standby state to be activated. The camera control signal may be generated and transmitted (step S240), and the steps after step S200 may be repeated.

Obviously, the above-described video recording method may be performed by an automated procedure according to a time series sequence by a software program or the like embedded in the vehicle video recording apparatus. The codes and code segments that make up the program can be easily deduced by a computer programmer in the field. In addition, the program is stored in a computer readable media, and read and executed by a computer to implement the method. The information storage medium includes a magnetic recording medium, an optical recording medium, and a carrier wave medium.

According to another embodiment of the present invention, when sufficient storage space is secured, the digital video recorder may store all the image data input from the plurality of cameras. By storing all the image data having various exposure times for the main subject, it is possible to minimize the loss of information due to the exposure error later, and to ensure that important information about the accident situation is recorded without exception.

9 is a block diagram illustrating a vehicle video recording apparatus using a multi-camera system according to another embodiment of the present invention, and FIG. 10 illustrates an image using the multi-camera system in a vehicle video recording apparatus according to another embodiment of the present invention. This is a flowchart of how to record.

The vehicle image recording apparatus 300 using the multi-camera system according to the present embodiment uses a plurality of cameras 110-1, 110-2,..., 110-n, hereinafter referred to as '110'. While shooting the same time and start shooting at the same time by setting different exposure time to obtain a plurality of image data of different brightness and save them all in the digital video recorder 300 first to avoid the gap due to parallax In addition, the efficiency of the memory may be improved by performing image analysis on the stored image data and deleting unnecessary items.

Referring to FIG. 9, the vehicle image recording apparatus 300 using the multi-camera system according to the present exemplary embodiment includes a plurality of cameras 110 mounted on a vehicle and capturing an image around the vehicle, and a plurality of cameras 110. It includes a digital video recorder 120 for receiving and storing the captured image.

The plurality of cameras 110 constitute a multi-camera system, and are basically set such that their exposure times are different from each other (t 1 ≠ t 2 ≠ ... ≠ t n ).

Each camera 110 is arranged so that most of the shooting areas can be superimposed on one another (for example, a plurality of cameras are disposed on the front of the vehicle video recording apparatus 100 to photograph the outside of the vehicle). A main subject (eg, a license plate of an opponent's vehicle, etc.) that is required may be located in an overlapping area so as to be photographed by a plurality of (eg, all) cameras 110.

In addition, each camera 110 is set to the same time to start shooting, so that the gap between the video data does not occur between each image data to minimize the loss of important information even in a sudden situation such as a car accident .

The digital video recorder 320 receives image data from each of the plurality of cameras 110, stores the image data, analyzes the stored image data, measures the brightness thereof, and deletes the remaining image data except image data having appropriate brightness. The storage efficiency of the memory can be improved.

The digital video recorder 320 includes an image storing unit 322, an image analyzing unit 324, an image selecting unit 326, an image deleting unit 328, and a program storing unit 330.

The image storage unit 322 stores image data input from each camera 110 in a predetermined storage space. The predetermined storage space is a space for permanently storing image data, and may be, for example, a nonvolatile memory such as NAND FLASH, NOR FLASH, SD CARD, MMC CARD, or CF CARD.

The image analyzer 324 performs histogram analysis on the input image data. Since the function of the image analyzer 324 is the same as that of the image analyzer 122 of FIG. 5, a detailed description thereof will be omitted.

The image selector 326 selects image data satisfying an appropriate brightness, that is, a brightness condition for identifying a main subject, based on the results analyzed by the image analyzer 324. The brightness condition that enables the identification of the main subject may be determined and set experimentally and / or statistically and may be changed by the user.

Methods for selecting image data having appropriate brightness may vary, and as described above, a method of using a brightness distribution curve of image data, a method of using a bias value, a combination thereof, and the like may be applied. As it has been described in detail above, the description thereof will be omitted.

The image deleting unit 328 deletes the remaining image data except the image data selected by the image selecting unit 326 among the image data stored in the image storage unit 322. By deleting unnecessary image data not having proper brightness, the storage space of the memory can be sufficiently secured, and the storage efficiency of the memory can be improved.

The program storage unit 330 stores a program for driving the vehicle video recording apparatus 300. For example, software for allowing one or more components of the image storage unit 322, the image analyzer 324, the image selector 326, the image deleter 328, etc. to operate may be stored in the program storage unit 330. Can be kept in storage. The program storage unit 330 may be a nonvolatile storage space.

Referring to FIG. 10, a method of recording an image in a vehicle image storage device 300 according to another embodiment is illustrated. Each step described below may be performed by each internal component of the vehicular image recording apparatus.

In operation S400, the plurality of cameras converts and outputs an external optical image into image data which is an electrical signal.

Here, each camera is set to have a different exposure time. In addition, most of the photographing areas photographed by each camera are overlapped with each other so that the main subjects are located in the overlapping regions so that an image of the main subjects can be stored regardless of which camera is selected. In addition, each camera performs shooting at the same time so that no gap is generated between the image data even if any camera is selected.

In operation S410, the image storage unit of the digital video recorder stores all image data provided from each of the plurality of cameras in a predetermined storage space.

In operation S420, the image analyzer analyzes brightness of image data input from each of the plurality of cameras stored by the image storage unit. Histogram analysis can be used as a method for analyzing brightness. Here, the brightness analysis may be performed on the entire area of the image data, or the brightness analysis may be performed only on the overlapping area including the main subject.

In operation S430, the image selector selects image data having an appropriate brightness by using the result analyzed in operation S420.

As a method for selecting image data having an appropriate brightness, a normality verification method for calculating and comparing deviations between the brightness distribution curve and the normal distribution curve of each image data, and calculating the bias value of the brightness distribution curve of each image data, There is a bias comparison method. The normality verification method and the bias value comparison method have been described in detail above, and thus description thereof will be omitted.

The image deleting unit deletes the remaining image data except the image data selected by the image selecting unit from the storage space.

Obviously, the above-described video recording method may be performed by an automated procedure according to a time series sequence by a software program or the like embedded in the vehicle video recording apparatus. The codes and code segments that make up the program can be easily deduced by a computer programmer in the field. In addition, the program is stored in a computer-readable information storage medium, and the program is read and executed by a computer to implement the method. The information storage medium includes a magnetic recording medium, an optical recording medium, and a carrier wave medium.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the following claims And changes may be made without departing from the spirit and scope of the invention.

1, 100, 300: vehicle video recording device
2, 110-1, 110-2, 110-n: camera
3, 120, 320: digital video recorder
122, 324: video analyzer
124: camera selection
126: image storage unit
128: camera control unit
130, 330: program storage unit
150a, 150b, 150c-1, 150c-2, 150d: main lobe
322: image storage unit
326: an image selector
328: video deleting unit

Claims (32)

An image recording apparatus for a vehicle that records and stores an image of a vehicle surroundings.
A plurality of cameras configured to have different exposure times to convert an external optical image into image data which is an electrical signal and output the converted image data; And
Including a digital video recorder for analyzing the brightness of the image data input from each of the plurality of cameras, and selects and stores the image data that satisfies the preset brightness conditions to enable identification of the main subject,
The digital video recorder,
An image analyzer for performing a histogram analysis on the image data;
A camera selector which selects a camera which outputs image data satisfying the preset brightness condition based on a result of the histogram analysis;
And a video storage unit for storing video data output from the selected camera.
delete The method of claim 1,
The camera selecting unit selects a camera that outputs the image data having the smallest deviation through a normality test calculating a deviation between the brightness distribution curve and the normal distribution curve of the image data according to the histogram analysis. Vehicle video recording device using a multi-camera system.
The method of claim 1,
And the camera selector selects a camera using a bias value indicating a skewness of the brightness distribution curve of the image data according to the histogram analysis.
5. The method of claim 4,
The bias value is a distance from the center of the brightness value expressible in the image data to the center line of the main lobe of the brightness distribution curve.
And the camera selector selects a camera that outputs image data having the smallest absolute value of the distance.
The method of claim 1,
And the image analyzer analyzes the histogram only in a region designated individually among images input by each camera.
The method of claim 1,
And a camera controller for generating and outputting a first camera control signal for turning off the operation power for a predetermined time to a camera other than the camera selected by the camera selection unit, among the plurality of cameras. Vehicle video recording apparatus using a multi-camera system characterized in that.
The method of claim 7, wherein
The camera controller generates and outputs a second camera control signal for turning on the operating power of the camera in the standby state after the predetermined time has elapsed, so as to be activated. Recording device.
The method of claim 1,
The plurality of cameras video recording apparatus for a vehicle using a multi-camera system, characterized in that for starting the image shooting at the same time.
An image recording apparatus for a vehicle that records and stores an image of a vehicle surroundings.
A plurality of cameras configured to have different exposure times to convert an external optical image into image data which is an electrical signal and output the converted image data; And
Including a digital video recorder for storing all the image data input from each of the plurality of cameras,
The digital video recorder,
An image storage unit which stores all image data input from the plurality of cameras;
An image analyzer for performing a histogram analysis on the image data;
An image selecting unit which selects image data satisfying a predetermined brightness condition based on a result of the histogram analysis;
And an image deleting unit for deleting the remaining image data except the image data selected by the image selecting unit.
The method of claim 10,
The digital video recorder analyzes the brightness of the image data input and stored from each camera, and deletes the remaining image data except for the image data satisfying a preset brightness condition to identify the main subject. Vehicle video recording device using the system.
delete The method of claim 10,
The image selecting unit selects the image data having the smallest deviation through a normality test calculating a deviation between the brightness distribution curve and the normal distribution curve of the image data according to the histogram analysis. Vehicle video recording device using the.
The method of claim 10,
And the image selector selects the image data using a bias value indicating a deviation degree of the brightness distribution curve of the image data according to the histogram analysis.
15. The method of claim 14,
The bias value is a distance from the center of the brightness value expressible in the image data to the center line of the main lobe of the brightness distribution curve.
And the image selector selects image data having the smallest absolute value of the distance.
The method of claim 10,
And the image analyzer analyzes the histogram only in a region designated individually among images input by each camera.
The method of claim 10,
The plurality of cameras video recording apparatus for a vehicle using a multi-camera system, characterized in that for starting the image shooting at the same time.
In the method for recording a video around the vehicle in a vehicle video recording apparatus including a plurality of cameras,
(a) analyzing brightness by receiving image data photographed by the plurality of cameras, wherein the plurality of cameras are set to have different exposure times;
(b) selecting a camera photographing image data that satisfies a predetermined brightness condition to identify a main subject according to an analysis result; And
(c) storing the image data photographed by the camera selected in step (b),
And (b) analyzing the brightness of the image data through histogram analysis.
delete 19. The method of claim 18,
In step (b), selecting a camera that outputs the image data having the smallest deviation through a normality test calculating a deviation between the brightness distribution curve and the normal distribution curve of the image data according to the histogram analysis. A video recording method characterized by the above.
19. The method of claim 18,
And (b) selecting a camera using a bias value representing a skewness of the brightness distribution curve of the image data according to the histogram analysis.
The method of claim 21,
The bias value is a distance from the center of the brightness value expressible in the image data to the center line of the main lobe of the brightness distribution curve.
And selecting a camera that outputs the image data having the smallest absolute value of the distance in the step (b).
19. The method of claim 18,
And performing a histogram analysis on an area designated individually among the images input by each camera in the step (a).
19. The method of claim 18,
Generating and outputting a first camera control signal for turning off the operation power for a predetermined time with respect to the remaining cameras other than the camera selected in step (b) among the plurality of cameras; Video recording method.
25. The method of claim 24,
And generating and outputting a second camera control signal for operating power of the camera in the standby state after the predetermined time has elapsed.
In the method for recording a video around the vehicle in a vehicle video recording apparatus including a plurality of cameras,
(a) storing all image data input from each of the plurality of cameras, wherein the plurality of cameras are set to have different exposure times;
(b) analyzing the brightness of the stored image data; And
(c) deleting the remaining image data except for image data that satisfies a predetermined brightness condition to identify the main subject according to the analysis result,
The step (b) is a video recording method, characterized in that for performing the histogram analysis only for the individually designated region of the image input by each camera.
The method of claim 26,
In step (c), deleting the remaining image data except the image data having the smallest deviation through a normality test calculating a deviation between the brightness distribution curve and the normal distribution curve of the image data according to the histogram analysis. A video recording method characterized by the above.
The method of claim 26,
And (c) selecting image data that satisfies the preset brightness condition by using a bias value indicating a skewness of the brightness distribution curve of the image data according to the histogram analysis.
29. The method of claim 28,
The bias value is a distance from the center of the brightness value expressible in the image data to the center line of the main lobe of the brightness distribution curve.
And deleting the remaining image data except the image data having the smallest absolute value of the distance in the step (c).
delete The method of claim 26,
And the cameras start capturing images at the same time.
32. A program of instructions that can be executed by a digital processing apparatus for performing the video recording method according to any one of claims 18, 20, 29 and 31 is tangibly implemented and read by the digital processing apparatus. Record carrier that records possible programs.
KR1020100060703A 2010-06-25 2010-06-25 Multi-camera video recording device and method for vehicle using multi-camera system KR101241803B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020100060703A KR101241803B1 (en) 2010-06-25 2010-06-25 Multi-camera video recording device and method for vehicle using multi-camera system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1020100060703A KR101241803B1 (en) 2010-06-25 2010-06-25 Multi-camera video recording device and method for vehicle using multi-camera system

Publications (2)

Publication Number Publication Date
KR20120000373A KR20120000373A (en) 2012-01-02
KR101241803B1 true KR101241803B1 (en) 2013-03-14

Family

ID=45608266

Family Applications (1)

Application Number Title Priority Date Filing Date
KR1020100060703A KR101241803B1 (en) 2010-06-25 2010-06-25 Multi-camera video recording device and method for vehicle using multi-camera system

Country Status (1)

Country Link
KR (1) KR101241803B1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9369665B2 (en) 2012-12-20 2016-06-14 Electronics And Telecommunications Research Institute Video recording apparatus for vehicle and video recording method for vehicle

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101439013B1 (en) 2013-03-19 2014-09-05 현대자동차주식회사 Apparatus and method for stereo image processing
US10691968B2 (en) 2018-02-08 2020-06-23 Genetec Inc. Systems and methods for locating a retroreflective object in a digital image
CN112714858B (en) * 2018-07-13 2024-07-09 拉布拉多系统公司 Visual navigation of mobile devices capable of operating under different ambient lighting conditions
US11188776B2 (en) 2019-10-26 2021-11-30 Genetec Inc. Automated license plate recognition system and related method
US11521371B2 (en) 2019-12-26 2022-12-06 Woven Planet North America, Inc. Systems and methods for semantic map-based adaptive auto-exposure
CN117911019A (en) * 2022-07-28 2024-04-19 华为技术有限公司 Payment method and related device
CN117750040B (en) * 2024-02-20 2024-06-07 浙江宇视科技有限公司 Video service balancing method, device, equipment and medium of intelligent server cluster

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006135435A (en) 2004-11-02 2006-05-25 Denso Corp Image photographing apparatus for vehicle
KR20100050759A (en) * 2008-11-06 2010-05-14 주식회사 셀픽 A vehicle block box apparatus using a plurality of camera
KR20100051244A (en) * 2008-11-07 2010-05-17 주식회사 케이제이몰 Apparatus and method of processing video in the video recording system for the vehicles

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006135435A (en) 2004-11-02 2006-05-25 Denso Corp Image photographing apparatus for vehicle
KR20100050759A (en) * 2008-11-06 2010-05-14 주식회사 셀픽 A vehicle block box apparatus using a plurality of camera
KR20100051244A (en) * 2008-11-07 2010-05-17 주식회사 케이제이몰 Apparatus and method of processing video in the video recording system for the vehicles

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9369665B2 (en) 2012-12-20 2016-06-14 Electronics And Telecommunications Research Institute Video recording apparatus for vehicle and video recording method for vehicle

Also Published As

Publication number Publication date
KR20120000373A (en) 2012-01-02

Similar Documents

Publication Publication Date Title
KR101241803B1 (en) Multi-camera video recording device and method for vehicle using multi-camera system
KR102565513B1 (en) Method and apparatus for multiple technology depth map acquisition and fusion
US8503818B2 (en) Eye defect detection in international standards organization images
EP1883050A2 (en) Vision-based method of determining cargo status by boundary detection
WO2020258816A1 (en) Systems and methods for image processing
US10467742B2 (en) Method and image capturing device for detecting fog in a scene
US20200336661A1 (en) Video recording and processing method and electronic device
CN105450932A (en) Backlight photographing method and device
CN110231018B (en) Structured light distance measuring method and device and computer readable storage medium
CN112584058B (en) Image acquisition system, method and device
JP2015532041A (en) Backlight correction method, apparatus and terminal
CN110798619B (en) Image processing method and device and electronic device
CN113691776A (en) In-vehicle camera system and light supplementing method
US11363211B2 (en) Image generation control device, image generation control method, and image generation control program
CN113747008A (en) Camera and light supplementing method
CN112770021B (en) Camera and filter switching method
JP6317914B2 (en) In-vehicle image processing device
CN108760245A (en) Optical element detection method and device, electronic equipment, readable storage medium storing program for executing
EP2658245B1 (en) System and method of adjusting camera image data
CN110930340B (en) Image processing method and device
US7949189B2 (en) Imaging apparatus and recording medium
US20130039576A1 (en) Method and device for analyzing an image of an image recording device for a vehicle
KR20180095251A (en) System for monitoring camera and method for correcting image
CN113055580B (en) Environment recognition method, shooting mode switching method, terminal and storage medium
US10609311B2 (en) Method and device for increasing resolution of an image sensor

Legal Events

Date Code Title Description
A201 Request for examination
E902 Notification of reason for refusal
E90F Notification of reason for final refusal
E701 Decision to grant or registration of patent right
GRNT Written decision to grant
FPAY Annual fee payment

Payment date: 20180226

Year of fee payment: 6

FPAY Annual fee payment

Payment date: 20190225

Year of fee payment: 7