KR101011698B1 - Image recoding device and method for vehicle - Google Patents

Abstract

PURPOSE: An image storing device for a car available for automatically converting a storing mode of a photographed image and a control method of the same are provided to sense a movement state of a car and to automatically convert a recording mode and a parking monitoring mode, thereby controlling storage of a photographed image. CONSTITUTION: An image storage control unit(50) obtains a first frame and a second frame of a random time interval among a photographed image of a frame buffer(20). The image storage control unit calculates image difference between frames in a set monitoring area. If an image difference exceeds the predetermined reference value, the image storage control unit determines movement of a car. The image storage control unit stores the photographed image by set of a constant recording mode.

Description

Vehicle image storage device that can automatically switch the recording mode of the captured image and its control method {IMAGE RECODING DEVICE AND METHOD FOR VEHICLE}

The present invention relates to a vehicle image storage device capable of automatically switching a storage mode of a captured image and a control method thereof, and more particularly, by storing an image of a front side or one side of a vehicle, which is installed in a vehicle and stored in a memory. The present invention relates to an image storage device for automatically checking a captured image later, and a method for automatically switching between an always-recording mode and a parking monitoring mode.

Recently, when faced with an unexpected accident that may occur when driving a vehicle, a vehicle image storage device that helps to analyze the cause of the accident later by recording and storing the situation before and after the accident has become popular.

However, such a vehicle image storage device operates when the engine is started or the vehicle's internal power is turned on to continuously photograph the front side (the direction in which the installed vehicle image storage device is directed), and store the captured image in a removable or internal fixed mass memory. It is based on the function (so-called 'always recording mode').

In addition, the recent more improved image storage device for a vehicle, when the vehicle is stopped and parked, when the vehicle attempts theft or the like and detects a fine movement in the vehicle, immediately starts the vehicle to photograph the front or theft Some useful features, such as alarm output, have been added, so-called 'parking monitoring mode'.

However, in order to set one of the normal recording mode and the parking monitoring mode or switch each mode in such a general vehicle image storage device, it is inconvenient that a user of the device must directly operate a switch or button provided in the device.

In addition, as a method for detecting the fine motion of the vehicle, an acceleration sensor or a motion detection sensor for detecting the movement of the vehicle image storage device itself is added to the vehicle image storage device, and when the movement is detected by the sensor It is determined that a fine motion has occurred, and the corresponding operation is processed. However, when an additional sensor is added as described above, a size and a price of the image storage device increase.

Accordingly, the present invention is to solve the above-described problems, it is possible to accurately determine the moving state of the vehicle without adding an acceleration sensor or a motion sensor, and to automatically take a picture taken by switching between the normal recording mode and the parking monitoring mode An object of the present invention is to provide a vehicle image storage device that efficiently uses a memory for storage and minimizes power consumption, and a method of operating the vehicle image storage device.

In addition, the present invention is to provide a vehicle image storage device that can accurately detect the fine motion occurred in the vehicle, to take a picture and store the surroundings when attempted theft of the vehicle or a contact accident during parking, and an operation method of such a vehicle image storage device For another purpose.

The present invention for achieving the above object, the camera module is installed in the vehicle, and continuously photographing the front image; A frame buffer configured to receive the captured image and temporarily store the captured image in frame units; An encoder for converting the image temporarily stored in the frame unit into digital data having an arbitrary data format; A mass memory for permanently storing the digital data according to an input storage command; A surveillance region configured to obtain a first frame and a second frame having an arbitrary time interval among the temporarily stored images from the frame buffer, and to include one or a plurality of pixels at the same position in the first frame and the second frame; Obtaining an image difference between each frame of the frame, and if the obtained image difference exceeds a predetermined reference value, determines that the vehicle is moving, and converts the front image including the first frame and the second frame. And an image storage controller for outputting the storage command to store digital data in the mass memory.

In addition, the surveillance area is characterized in that set in each corner of the frame.

In addition, the surveillance region is set to each side of the frame.

The first frame and the second frame may be set from two consecutive frames photographed by the camera module and temporarily stored in the frame buffer.

In addition, the frame buffer has a storage space in which two frames can be stored. When one frame is input from the camera module, the frame buffer deletes a previously stored frame among the two frames of the storage space and stores the input frame. Characterized in that.

In addition, the image storage controller calculates an image difference for each pixel for a plurality of pixels constituting the surveillance area, and the number of pixels determined that the calculated image difference for each pixel exceeds the reference value is a predetermined criterion. When the number of pixels is exceeded, the vehicle is determined to be moving.

The image storage controller may be configured to set a plurality of the surveillance regions, and the vehicle moves when the number of the surveillance regions detected as the vehicle is moving among the plurality of surveillance regions exceeds a predetermined reference region number. It is characterized by determining as being.

The image storage control unit may output the storage command to permanently store the photographed front image in the mass memory for a preset time from the time of the determination when the vehicle is determined to be moving. .

In addition, the present invention for achieving the above object is installed in a vehicle, the moving state of the vehicle by using the image difference in the surveillance region set in advance from the first frame and the second frame of the front image of the front continuous shooting A method of determining, comprising: an imaging step of acquiring the first frame and the second frame which are continuously photographed at an arbitrary time interval; Calculating an image difference between each frame in the surveillance area set to include one or a plurality of pixels at the same position in the first frame and the second frame; Comparing the obtained image difference with a predetermined reference value, if the obtained image difference exceeds the reference value, it is determined that the vehicle is moving, permanently storing each frame, and if the obtained image difference is equal to or less than the reference value, And a moving state determination step of returning to the step of acquiring each frame without permanently storing the frame.

The surveillance area is set at a position in contact with one or a plurality of corners of the frame or one or a plurality of sides of the frame, and includes one or a plurality of pixels.

The moving state determination step may include: calculating an image difference for each pixel of a plurality of pixels constituting the surveillance area; And determining that the vehicle is moving when the number of pixels determined to be greater than the reference value exceeds the predetermined reference pixel.

The moving state determination step may include: determining a surveillance region in which the vehicle is detected to be moving among the plurality of surveillance regions set in each frame; And determining that the vehicle is moving when the value of counting the number of monitoring areas detected as the vehicle is moving exceeds a predetermined reference area number.

According to the vehicle image storage device and method having the above-described configuration, by detecting the moving state of the vehicle to automatically switch between the always-recording mode and the parking monitoring mode to control the storage of the captured image to save the memory and power consumption The efficiency can be improved.

In addition, since the present invention can accurately detect the fine motion generated in the vehicle and store images taken around the vehicle without adding an acceleration sensor or a motion detection sensor, the present invention can effectively respond to theft attempts or contact accidents while parking. Can be.

1 is a view showing a form in which the vehicle image storage device according to the present invention is mounted toward the front of the vehicle.
2 is a block diagram showing the configuration of a vehicle video storage device according to the present invention.
3 is a flowchart illustrating an operation of a vehicle video storage device according to the present invention.
4 is a flowchart illustrating a movement state determination operation of a vehicle in the vehicle image storage device according to the present invention.
Fig. 5 shows an example of a surveillance region set in each frame, an example in which a surveillance region is set in a captured front image, and an example in which a video difference is calculated in any one of the surveillance regions. It is a figure for demonstrating a method.

Hereinafter, with reference to the accompanying drawings, the configuration and operation of the vehicle image storage device according to the present invention will be described in detail.

1 shows a form in which a vehicle image storage device according to the present invention is mounted on a vehicle. Referring to FIG. 1, a vehicle image storage device 100 is generally disposed in any direction of the front, rear, or both sides of a vehicle at a position that does not obstruct the driver's field of view, such as the front of a room mirror of a vehicle interior. In this case, the image of the heading is taken and stored in the memory. In the future, the user may randomly access the stored image and check it again.

2 is a view for explaining the configuration of a vehicle video storage device according to the present invention. According to FIG. 2, the vehicle image storage device 100 includes a camera module 10, a frame buffer 20, an encoder 30, a mass memory 40, and an image storage controller 50. Is done.

The camera module 10 photographs the forward head to generate and output a forward image that is a still image.

In general, the camera module 10 outputs each still image by capturing about 30 times per second, and the still images are displayed at high speed in a predetermined display device (not shown). .

The frame buffer 20 is a memory for temporarily storing still images (hereinafter, referred to as frames) for the front image output from the camera module 10. The frame buffer 20 has a storage space for storing one or a plurality of frames. When the storage space is full, the frame buffer 20 deletes the first stored frame and stores a newly photographed and input frame. In one embodiment of the present invention, the frame buffer 20 has a storage space for storing two frames at the same time.

The encoder 30 encodes each frame of the front image stored in the frame buffer 20 into digital data having a predetermined format according to a predetermined image compression algorithm.

The mass memory 40 is a generally widely used storage medium, such as an SD memory card, a flash memory, an HDD, and an optical disk, and is applied to permanently store input data. The mass memory 40 is preferably a removable storage medium capable of moving data stored in the vehicle image storage apparatus 100 at random.

The image storage controller 50 controls the overall operation of the vehicle image storage device 100. That is, when driving of the image storage device is input by a user's operation, the camera module 10 controls the operation of photographing the front to continuously output the frames of the front image, and at least two frames from the frame buffer 20. Obtaining a frame (a first frame and a second frame), and determining a moving state of the vehicle image storage apparatus 100, that is, a moving state of the vehicle equipped with the vehicle image storage apparatus, using the obtained two frames, According to the moving state of the vehicle, the obtained two frames are stored in the mass memory 40 or erased from the frame buffer 20 as it is.

At this time, in determining the moving state of the vehicle, when it is determined that the vehicle is moving, the two frames (first frame and second frame) acquired for determining the moving state of the vehicle are not stored, and these two frames are not stored. It is also possible to control to store the forward image for a predetermined time immediately after the vehicle is determined to be moving, regardless of the movement state determination result.

On the other hand, when the vehicle movement state determination by the first frame and the second frame is completed, the image storage control unit 50 may execute the movement state determination of the vehicle using the third frame immediately following the second frame. . Alternatively, the movement state determination may be restarted after a predetermined time (for example, 0.5 seconds, 5 seconds, etc.) after the one movement state determination by the first frame and the second frame is completed.

Meanwhile, the vehicle image storage apparatus 100 according to the present invention may further include a stream buffer (not shown) which is temporarily stored before the front image converted into a predetermined format by the encoder 30 is stored in a large memory. It may be. In addition, the video storage control unit 50 can control the permanent storage of the front image to the mass memory 40 by controlling the data input / output operation of the stream buffer.

FIG. 5 is a diagram for explaining a method for determining a moving state of a vehicle, and FIGS. 5A and 5B show an example of a surveillance area set for each frame of a front image. That is, one or more surveillance zones may be set at each corner portion in the frame having a quadrangular shape, and one or more plurality may be set at each edge portion of the frame. Furthermore, it may be set at any position such as the center of the frame.

Meanwhile, the following method may be used to calculate an image difference by comparing each surveillance area with respect to each of the two frames, and to determine the moving state of the vehicle using the calculated image difference.

In this case, the image difference to be obtained may use an image difference calculation method widely used in conventional image compression techniques, and thus, detailed description thereof will be omitted.

First, an image difference is calculated for each pixel in any one of a plurality of monitoring areas including a plurality of pixels to determine a pixel whose image difference exceeds a predetermined reference value, and the number of reference pixels is a preset number of pixels. In the case of abnormality, it is possible to determine that the vehicle has moved in the monitoring area.

That is, when any surveillance area A is set to an area including 16 pixels of 4x4 as shown in FIG. 5E, it is determined that the image difference exceeds 10% among 10 pixels among the 16 pixels. Only in this case, it is possible to determine that the movement of the vehicle is detected in the monitoring area A. FIG.

FIG. 5 (f) shows that the image difference exceeds the reference value in 11 pixels, and in this case, it is possible to determine that the vehicle is detected to have moved in the monitoring area A. FIG. That is, referring to FIGS. 5 (c) and 5 (d), for example, the surveillance area A is displayed by photographing a part of a tree in FIG. 5 (c), which may be a first frame. Since the tree is not photographed in FIG. 5 (d), which may be the second frame, an image difference may appear large at a pixel at the location where the tree was photographed, and may exceed the reference value of the image difference. If 11 is displayed as in 5 (f), it is possible to determine that the vehicle is moving in the monitoring area A.

Further, in the determination of the moving state of the vehicle, it is possible to finally determine that the vehicle is moving when the number of the monitoring regions determined that the vehicle is moving among the plurality of monitoring regions set in the frame is equal to or larger than the preset reference region number.

That is, in the case where four surveillance regions are set for the frame and the number of reference regions is set to three, if the number of surveillance regions determined that the vehicle is moving is three as shown in FIGS. 5 (c) and 5 (d). In this case, it is possible to finally determine that the vehicle is in a moving state.

Next, an operation of the vehicle image storage device according to the present invention will be described with reference to FIG. 3. First, when the vehicle image storage apparatus 100 is driven by a user's manipulation or the vehicle is connected to the power source (S10), the image storage apparatus 100 captures the front image by photographing the front side through the camera module 10. It generates (S12).

When the front image is photographed, the image storage control unit 50 selects any one frame among the front images photographed and input in a plurality of frames per second and sets it as the first frame (S14). When the first frame is selected, the frames photographed and input continuously after a predetermined time are selected from the continuously inputted frames or the first frames and set as the second frames (S16).

When two frames are selected, the two selected frames are compared to determine whether the vehicle is moving or parked.

That is, according to a preset surveillance region, an image of a portion corresponding to the surveillance region is extracted from the first frame and the second frame of the captured front image, and the partial image extracted from the first frame and the portion extracted from the second frame. The image difference is obtained by comparing the images (S18).

When the image difference is calculated, the calculated image difference is compared with a reference value of a predetermined moving state determination (S20), and when the calculated image difference exceeds the reference value, the vehicle is determined to be in a moving state (S22), and the continuous recording mode By operating as a so that all the captured front image can be stored permanently in the large memory (S24).

On the other hand, if the calculated image difference is less than or equal to the reference value, it is determined that the vehicle is parked and stopped (S32), the vehicle is operated in the parking monitoring mode, and then the front image is continuously monitored to continuously determine the moving state of the vehicle. (S34)

Further, when it is determined that the vehicle is in a moving state or is determined to be stationary, the moving state determination can be restarted immediately or after waiting for a predetermined time (for example, 0.5 seconds, 5 seconds).

In addition, even when it is determined that the vehicle is in a stopped state, by forcibly storing the forward image photographed for a predetermined time (for example, 1 minute), the vehicle is temporarily stopped, the instantaneous determination and error of the image storage device, In the case where the vehicle is moving but can be temporarily determined to be stationary, it is possible to minimize an error in which the image captured and determined by the parking state is not stored without being erased.

Next, FIG. 4 is a flowchart explaining the moving state determination method of a vehicle in detail in the flowchart of FIG. 3 mentioned above.

First, when the first and second frames are obtained as in steps S14 and S16 of FIG. 3, one surveillance area is selected for the vehicle movement state determination in the first and second frames (S212). Any one of a plurality of pixels constituting the selected surveillance region is selected (S214).

Next, an image difference between the first frame and the second frame is calculated with respect to the position of the selected pixel (S216), and the calculated image difference is compared with a reference value (S218).

In this case, when the calculated image difference exceeds the reference value, it is assumed that the vehicle movement is detected in the corresponding pixel, and the number of pixels is counted (S220). If the calculated image difference is less than or equal to the reference value, the number of pixels is not counted.

When the image difference comparison is completed for all the pixels in the selected surveillance area (S222), it is determined whether the number of counted pixels is equal to or greater than the preset reference pixel number (S226). On the other hand, if the image difference comparison is not completed for all the pixels in the selected surveillance region, the process returns to step S216 for another pixel in the surveillance region and repeats the image difference comparison process (S224).

If it is determined that the number of pixels counted in step S226 is equal to or greater than the number of reference pixels, it is determined that the vehicle is determined to be moving in the selected monitoring area (S228), and the number of monitoring areas is counted (S232). On the other hand, if the number of counted pixels is less than the reference number of pixels, it is determined that the vehicle is in the stopped state in the selected monitoring area and the number of monitoring areas is not counted (S230).

Subsequently, if the image difference comparison with respect to all surveillance regions set in the first frame or the second frame is completed (S234), the number of surveillance regions counted so far and the preset reference region number are compared (S238), and the counted surveillance If it is determined that the number of areas is equal to or greater than the reference area, the vehicle is finally determined to be moving (S22), and the process proceeds to step S23 of FIG.

On the other hand, if the video difference comparison with respect to all the surveillance areas is not completed in step S234, the next surveillance area is selected, and the process returns to step S214 to select any pixel to perform the video difference comparison. (S236).

In addition, if it is determined that the number of monitored areas counted in step S238 is less than the reference area number, it is finally determined that the vehicle is in a stopped state (S32), and the process proceeds to step S34 of FIG.

As described above, the moving state of the vehicle is determined using the front image, and according to the determined result, it is possible to automatically switch between the normal recording mode for continuously storing the front image and the parking monitoring mode without storing the front image. The user can eliminate the hassle of manually operating the mode.

In addition, even when a small movement occurs in the vehicle due to a contact accident caused by a human body, an object, or another vehicle while parked, the movement is immediately detected and the front image is recorded and stored, which helps to resolve the future event. It becomes possible.

In addition, when it is determined that the vehicle is parked, if there is no security release operation such as security release by the user's access to the smart key or operation of the car key, theft of the vehicle is detected. An attempt may be deemed to have occurred, an alarm sound may be output, or an alarm signal may be transmitted to a user's mobile phone or police station through a communication network.

On the other hand, two frames may be used as the frame for the front image used for the movement state determination as described above, or a plurality of frames may be used.

In this case, a plurality of frames are continuously selected or have the same time interval or any different time interval, and any one of the selected plurality of frames is set as the reference frame, and each of the selected plurality of frames and the reference frame Are compared with each other, the frames determined to be moved relative to the reference frame are extracted, and when the number of the extracted frames exceeds the predetermined reference number, it is possible to determine that the vehicle is in the moving state.

According to this determination method, more accurate movement state determination can be performed.

On the other hand, in the determination of the movement state by the method as described above, when the image difference calculated in step S20 or the like exceeds the reference value, the vehicle is immediately determined to be moving, or as soon as the calculated image difference exceeds the reference value. It is also possible not to determine that the vehicle is in the stationary state, and to finally determine the movement state with reference to the following multiple movement state determination results.

100: vehicle video storage device
10: camera module
20: frame buffer
30: encoder
40: large memory
50: image storage control unit

Claims (12)

A vehicle image storage device capable of automatically switching a storage mode to store a captured image when the vehicle is moving and not to store the captured image when the vehicle is stopped:
A camera module installed in the vehicle and continuously photographing the front of the vehicle;
A frame buffer for receiving the image photographed by the camera module and temporarily storing the image photographed by the frame unit;
An encoder for converting the image temporarily stored in the frame unit into digital data having an arbitrary data format;
A mass memory for permanently storing the digital data according to an input storage command;
Acquiring a first frame and a second frame having an arbitrary time interval among the photographed images temporarily stored in the frame buffer, and any mutually identical positions contacting each corner or each side in the first frame and the second frame. A surveillance region including a plurality of pixels is set in the apparatus, and when it is determined that the calculated image difference exceeds a predetermined reference value after calculating an image difference between frames in the surveillance area, the vehicle is determined to be moving and the And an image storage control unit for outputting the storage command to store the digital data obtained by converting the photographed image including the first frame and the second frame into the mass memory. Switchable vehicle video storage. delete delete The method of claim 1,
The first frame and the second frame,
The vehicle image storage device capable of automatically switching the storage mode of the captured image, characterized in that it is set from two consecutive frames taken by the camera module and temporarily stored in the frame buffer. The method of claim 4, wherein
The frame buffer has a storage space in which two frames can be stored, and when frames of an image photographed from the camera module are input one by one, the previously stored frame is deleted from the two frames already stored in the storage space and the input is performed. The vehicle image storage device capable of automatically switching the storage mode of the captured image, characterized in that for storing the frame. The method of claim 1,
The image storage control unit,
After calculating the image difference for each pixel among the pixels constituting the surveillance region, the number of pixels determined to be greater than the reference value is calculated, and the calculated number is determined. And when the number of reference pixels is exceeded, the vehicle image storage device capable of automatically switching the storage mode of the captured image, characterized in that the vehicle is determined to be moving. The method of claim 1,
The image storage control unit,
A plurality of surveillance regions are set in the first frame and the second frame, and an image difference for each pixel is calculated for each of the pixels constituting each of the plurality of configured surveillance regions, and the calculated inter-frame pixel The number of pixels for which the image difference for each other exceeds the reference value is calculated, the number of surveillance areas determined that the calculated number exceeds a predetermined reference pixel number is obtained, and the number of the obtained surveillance areas is a predetermined reference area number. The vehicle image storage device capable of automatically switching the storage mode of the captured image, characterized in that it is determined that the vehicle is moving when exceeding. The method of claim 1,
The image storage control unit,
And when the vehicle is determined to be moving, automatically outputting the storage command to permanently store the photographed image in the mass memory for a preset time from the determination time point. Vehicle video storage device can be switched to. As a method for determining a moving state of the vehicle and automatically switching the storage mode so as to store the captured image when the vehicle is moving and not to store the captured image when the vehicle is stopped:
A photographing step of acquiring a first frame and a second frame of continuously photographing the front of the vehicle at an arbitrary time interval;
Setting a surveillance area including a plurality of pixels at any one same position in contact with each corner or each side in the first frame and the second frame;
An image difference per pixel is calculated for each of the pixels constituting the surveillance area, the number of pixels determined to be greater than a predetermined reference value is calculated, and the calculated number is determined. Determining that the vehicle is moving when the number of reference pixels is greater than and storing the captured image including the first frame and the second frame in a large memory; a storage mode of the captured image How to control the vehicle image storage device that can be automatically switched. delete delete As a method for determining a moving state of the vehicle and automatically switching the storage mode so as to store the captured image when the vehicle is moving and not to store the captured image when the vehicle is stopped:
A photographing step of acquiring a first frame and a second frame of continuously photographing the front of the vehicle at an arbitrary time interval;
Setting a plurality of surveillance regions including a plurality of pixels at any one and the same position in contact with each corner or each side in the first frame and the second frame;
For each of the pixels constituting each of the plurality of surveillance regions, an image difference between pixels is calculated between the frames, and the number of pixels whose pixel difference between the frames exceeds a predetermined reference value is calculated. Obtaining the number of surveillance areas determined that the number exceeds the predetermined reference pixel number, and when the number of the obtained surveillance areas exceeds the predetermined reference area number, it is determined that the vehicle is moving and the first frame And storing the captured image including the second frame in a large memory. The control method of the vehicle image storage device of claim 1, wherein the storage mode of the captured image may be automatically switched.

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