JP4363156B2 - Ambient photography device for vehicles - Google Patents

Description

  The present invention relates to a vehicle surrounding photographing apparatus that is mounted on a vehicle and photographs an image around the vehicle.

Currently, a back view that assists backward driving by monitoring the field of view behind the vehicle using an electronic camera that is attached to the rear of the vehicle and captures an image of the rear of the vehicle and a monitor provided in the driver's seat. Many vehicles are equipped with a “monitor”. Such a technique is described, for example, in Patent Document 1 below.
Considering the purpose of use, it is ideal to place the camera in the center of the rear of the vehicle. However, in actuality, it is often attached at a position offset from the center of the rear part of the vehicle due to the layout and design of each part.

JP 2002-274257 A

  There is a bias in the image taken by the camera attached to the position offset from the center of the rear part of the vehicle as described above. For this reason, the driver has a problem that it is difficult to grasp the positional relationship between the vehicle and the surroundings of the vehicle.

  The present invention provides a vehicle surrounding photographing apparatus that corrects a bias of an image photographed by a camera attached to an offset position and allows a driver to easily grasp the positional relationship between the vehicle and the vehicle surroundings. For the purpose.

  In order to solve the above problems, the present invention includes a storage unit that stores an offset amount or a display start position for each raster of an image captured by an imaging unit attached at a position offset from the vehicle center, And a display control means for controlling the display start position based on the offset amount or the display start position, and a display means for displaying based on the display data from the display control means.

  According to the present invention, it is possible to correct a bias of an image captured by a camera attached to an offset position, and a driver can easily grasp a positional relationship between the vehicle and the surroundings of the vehicle, thereby improving safety when driving the vehicle. It is possible to provide a vehicle surrounding photographing device that can be used.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings described below, components having the same function are denoted by the same reference numerals, and repeated description thereof is omitted.
FIG. 2 is a diagram showing a virtual line with respect to the vehicle, in which (a) is a top view of the vehicle and (b) is a front front view of the vehicle.
In FIG. 2, 101 is a vehicle, 102 is an electronic camera that is an imaging means attached at a position slightly offset to the left from the center of the rear part of the vehicle 101, and 103 is a tow attached to the center of the rear part of the vehicle 101. Hook, Line A is the virtual line in the center of the vehicle 101, Line B is the virtual line on the right side of the vehicle 101, Line B 'is the virtual line on the left side of the vehicle 101, DR is the distance between Line A and Line B, DL is the distance between Line A and Line B ′.

FIG. 3 is a view showing a camera image taken by the camera 102 attached at a position slightly offset to the left side from the center of the rear part of the vehicle 101.
In FIG. 3, C is the center line of the screen, and dn is the distance (offset amount) between Line A and the center line C of the screen in each raster. Note that a raster refers to a linear image in the horizontal direction.

  If the virtual line Line AB, the virtual line Line B on the right side, and the virtual line Line B ′ on the left side of the vehicle 101 in FIG. 2 exist on the ground, the camera image by the camera 102 attached at the offset position is As shown in FIG. Considering the positional relationship between the vehicle 101 and the virtual lines Line A, Line B, and Line B ′, in the camera image by the camera 102, Line B and Line B ′ are photographed symmetrically about Line A. Is ideal. However, the camera 102 at the offset position captures a biased image as shown in FIG. Since the images are biased, it is difficult for the driver to grasp the positional relationship between the vehicle 101 and the surroundings of the vehicle 101. The present invention corrects a bias of an image captured by a camera 102 attached at an offset position, and allows a driver to easily grasp the positional relationship between the vehicle 101 and the surroundings of the vehicle 101. An imaging device is realized.

FIG. 1 is a block diagram showing a configuration of a vehicle surrounding photographing apparatus according to an embodiment of the present invention.
In FIG. 1, 102 is a camera attached at a position slightly offset to the left from the center of the rear part of the vehicle 101 (FIG. 2), 104 is an image processing device, and 105 is a first device provided in the image processing device 104. Storage means 106 is a second storage means provided in the image processing apparatus 104, 107 is a display control means provided in the image processing apparatus 104, and 108 is a first storage means 105 and a second storage means 106. A switch (switching means) 109 for switching between and is a monitor which is provided in the driver's seat of the vehicle 101 and is a display means for giving information to the driver.

  The xyz coordinate system is taken as shown in FIG. The height z = 0 is the ground, and z> 0 above the ground. As described above, the camera 102 is installed at the rear portion of the vehicle 101 and photographs the rear of the vehicle 101. The camera 102 is installed offset in the x direction. A tow hook 103 is attached to the center of the rear part of the vehicle 101, and the height of the tow hook 103 is z = h. Consider the center virtual line Line A (x = 0), the right virtual line Line B (x = 1 m), and the left virtual line Line B ′ (x = −1 m). The height of Line A, B, B 'is z = h. Lines B and B ′ are set at symmetrical positions with respect to Line A. From the mounting position of the camera 102 and the camera characteristics, it is possible to uniquely determine how the lines A, B, and B ′ are captured by the camera 102. This may be obtained by experiments, or a model that reproduces camera characteristics may be used. When the angle of view of the camera 102 is narrow, Line B, B ′ goes out of the screen halfway, so Line B, B ′ set at an interval that fits on the screen is used. For example, Line B (x = 0.8 m), Line B ′ (x = −0.8 m).

  Here, a camera image by the camera 102 is considered with reference to FIG. Lines A, B, and B ′ are drawn in the camera image. The camera image is realized as an aggregate of rasters. Consider the distance DR (see FIG. 2) between Line A and Line B and the distance DL between Line A and Line B ′ for each raster. Since the camera 102 is mounted with an offset, the distance DL and the distance DR do not match. Coefficients (expansion / contraction rate, expansion / contraction information) k1 and k2 satisfying DL × k1 = DR × k2 are calculated. The distance (offset amount) d between Line A and the center line C of the screen, that is, the distance (offset amount) dn between Line A and the screen center line C in each raster is obtained, and d, k1, and k2 are image processing devices. It is held in the storage means 105 and 106 in 104. D, k1, and k2 are stored in the storage means 105 and 106 for all rasters. The first storage means 105 holds d, k1, and k2 for each raster that is optimal for the ground with z = 0. Further, the second storage means 106 has an optimum value for each raster, d, for a predetermined surface of z> 0 above the ground, for example, a predetermined surface of z = h to which the tow hook 103 is attached. Holds k1 and k2.

  The image processing apparatus 104 has a function of expanding and contracting an arbitrary range at an arbitrary magnification when drawing each raster, and also has a function of changing the display start position of the raster. Since the processing is performed on a raster, one-dimensional data is processed, and the function can be easily realized.

  The switch 108 is attached to the image processing apparatus 104. By switching the switch 108, the operation when the virtual lines LineA, LineB, and LineB ′ are at the ground height z = 0, and LineA, LineB, and LineB ′ Can be switched to the operation when the height of the tow hook 103 is at the height z = h. The former operation applies the optimal correction to see the road surface, and the latter operation applies the optimal correction according to the height of the tow hook 103, so the former is selected during normal reverse operation, For example, when connecting to a towed object such as another vehicle using the tow hook 103, the latter is selected, and the image according to the purpose is presented to the driver by changing the correction degree of the image bias. Can do.

FIG. 4 is a flowchart in the vehicle surrounding photographing apparatus of the present embodiment.
Hereinafter, a processing flow in the vehicle surrounding photographing apparatus of the present embodiment will be described with reference to FIG.
By the driver's manual operation of the switch 108, the reverse operation during normal operation or the operation during pulling is selected.
An image photographed by the camera 102 (see FIG. 1) is sent to the image processing device 104, and the image processing device 104 acquires raster data (S41).
When acquiring the raster data, the image processing apparatus 104 holds the raster data in an internal frame buffer (not shown), and stores the offset amount d and the expansion / contraction coefficients k1, k2 corresponding to the raster in the first storage unit 105. It is read from (when the normal reverse operation is selected by the switch 108) or the second storage means 106 (when the pulling operation is selected by the switch 108) (S42).
The image processing apparatus 104 uses the offset amount d to divide the raster data into two, left raster data L and right raster data R, at a point offset by d from the center of the raster (S43).
The left raster data L is expanded or contracted by a coefficient k1 (S44).
The right raster data R is expanded or contracted by a coefficient k2 (S45).
The raster data is synthesized by arranging the stretched left and right raster data R at the center of the raster at the contact point (S46).
The display data created by the image processing device 104 is sent to the monitor 109 and presented to the driver (S47). The operations from S41 to S47 are repeated for all rasters.
The raster data is larger than the display width depending on the values of d, k1, and k2, but the data portion outside the range is not used for display. This processing may be performed in units of rasters when each raster data is acquired, or may be sequentially performed when screen data is acquired.

As described above, in the vehicle surrounding photographing apparatus according to the present embodiment, the camera 102 attached at a position offset from the center of the vehicle 101, and the offset amount d and the expansion / contraction of the image photographed by the camera 102 for each raster. Storage means 105 and 106 for storing the coefficients k1 and k2 as information, and the display start position is controlled based on the offset amount d for each raster, and a predetermined range is expanded and contracted at a predetermined magnification based on the coefficients k1 and k2. The display control unit 107 and a monitor 109 that performs display based on display data from the display control unit 107 are provided. Instead of the offset amount, the display start position may be stored in the storage units 105 and 106, and the display control unit 107 may control the display start position based on the display start position. With such a configuration, image bias due to the mounting position of the camera 102 mounted at a position slightly offset to the left from the center of the rear part of the vehicle 101 is reduced, and the driver can It is possible to easily grasp the positional relationship between the two. Therefore, the safety of the driver when driving the vehicle can be improved.
The storage means includes first storage means 105 for storing the offset amount d (or display start position) for each raster at the height z = 0 of the ground and the coefficients k1, k2, and the height z = above the ground. a second storage means 106 for storing the offset amount d (or display start position) for each raster on the surface to which the predetermined tow hook 103, for example, is attached, and coefficients k1 and k2, and the first storage means 105; And a switch 108 for switching between the second storage means 106. Thereby, the image according to the purpose can be presented to the driver by changing the correction degree of the image bias between the normal backward movement operation and the traction operation.

The embodiment described above is described in order to facilitate understanding of the present invention, and is not described in order to limit the present invention. Therefore, each element disclosed in the above embodiment includes all design changes and equivalents belonging to the technical scope of the present invention.
That is, the storage means 105 and 106 store the offset amount d (or display start position) for each raster, and the display control means 107 determines the display start position based on the offset amount d (or display start position) for each raster. A configuration of controlling is also possible. In this case, the effect as great as that of the above embodiment cannot be obtained, but the effect of reducing the image bias due to the mounting position of the camera 102 can be obtained.
FIG. 5 is a flowchart of the vehicle surrounding photographing apparatus having such another configuration according to the present embodiment.
Hereinafter, a processing flow in the vehicle surrounding photographing apparatus having such another configuration will be described with reference to FIG.

  By the driver's manual operation of the switch 108, the reverse operation during normal operation or the operation during pulling is selected.

An image photographed by the camera 102 (FIG. 1) is sent to the image processing device 104, and the image processing device 104 acquires raster data (S51).
When the image processing apparatus 104 acquires the raster data, the image processing apparatus 104 stores the raster data in an internal frame buffer (not shown), and an offset amount d corresponding to the raster (or a display start position calculated in consideration of the offset amount d). Is read from the first storage means 105 (when the normal reverse operation is selected by the switch 108) or the second storage means 106 (when the traction operation is selected by the switch 108) (S52).
Using the offset amount d, the image processing apparatus 104 sets a display start position at a point offset by d from the center of the raster, and creates raster data (S53).
The display data created by the image processing device 104 is sent to the monitor 109 and presented to the driver (S54). The operations from S51 to S54 are repeated for all rasters.
Depending on the value of d, the raster data is larger than the display width, but the data portion outside the range is not used for display. In addition, this processing may be performed in units of rasters when each raster data is acquired, or may be sequentially processed when screen data is acquired.

Storage means 105 and 106 store coefficients k1 and k2 which are expansion / contraction information for each raster, and display control means 107 expands and contracts a predetermined range at a predetermined magnification based on the coefficients k1 and k2 for each raster. (The flowchart is not shown). In this case, the effect as great as that of the above embodiment cannot be obtained, but the effect of reducing the image bias due to the mounting position of the camera 102 can be obtained.
Further, as the storage means, only the first storage means 105 for storing the offset amount d (or display start position) for each raster at the height z = 0 of the ground and the coefficients k1, k2 is provided, and the height z above the ground is provided. There is no need to provide the second storage means 106 for storing the offset amount d (or display start position) for each raster and the coefficients k1 and k2 on a predetermined surface of = h, for example, the surface to which the tow hook 103 is attached.

It is a block diagram which shows the structure of the periphery imaging device for vehicles of embodiment of this invention. FIG. 2 is a diagram illustrating a virtual line with respect to the vehicle, in which (a) is a top view of the vehicle and (b) is a front view of the vehicle. It is a figure which shows the camera image image | photographed with the camera attached to the position slightly offset to the left side from the center of the vehicle rear part. It is a flowchart in the surrounding photography apparatus for vehicles of this Embodiment. It is a flowchart in the surrounding photography apparatus for vehicles of another structure of this Embodiment.

Explanation of symbols

101 ... vehicle 102 ... camera
103 ... Tow hook 104 ... Image processing device
105 ... first storage means 106 ... second storage means
107 ... Display control means 108 ... Switch
109… Monitor
Line A ... Virtual line in the center Line B ... Virtual line on the right
Line B '... Virtual line on the left
DR… Distance between Line A and Line B DL… Distance between Line A and Line B '
C ... Center line of the screen dn ... Offset amount for each raster

Claims (6)

Imaging means attached at a position offset from the center of the vehicle;
Storage means for storing an offset amount or display start position for each raster of the image captured by the imaging means;
Display control means for controlling the display start position based on the offset amount or the display start position for each raster;
A vehicle surrounding photographing apparatus comprising: display means for performing display based on display data from the display control means. The storage means
First storage means for storing the offset amount or display start position for each raster at the height of the ground;
A second storage means for storing the offset amount or display start position for each raster on a predetermined surface at a height above the ground;
2. The vehicle surrounding photographing apparatus according to claim 1, further comprising a switching unit that switches between the first storage unit and the second storage unit. Imaging means attached at a position offset from the center of the vehicle;
Storage means for storing expansion / contraction information for each raster of the image taken by the imaging means;
Display control means for expanding and contracting a predetermined range at a predetermined magnification based on the expansion / contraction information for each last;
A vehicle surrounding photographing apparatus comprising: display means for performing display based on display data from the display control means. The storage means
First storage means for storing the expansion / contraction information for each raster at the height of the ground;
A second storage means for storing the expansion / contraction information for each raster on a predetermined surface at a height above the ground;
4. A vehicle surrounding photographing apparatus according to claim 3, further comprising switching means for switching between the first storage means and the second storage means. Imaging means attached at a position offset from the center of the vehicle;
Storage means for storing an offset amount or display start position for each raster of the image captured by the imaging means, and expansion / contraction information;
Display control means for controlling a display start position based on the offset amount or display start position for each raster, and expanding / contracting a predetermined range at a predetermined magnification based on the expansion / contraction information;
A vehicle surrounding photographing apparatus comprising display means for performing display based on display data from the display control means. The storage means
First storage means for storing the offset amount or display start position and expansion / contraction information for each raster at the height of the ground;
A second storage means for storing the offset amount or display start position and expansion / contraction information for each raster on a predetermined surface at a height above the ground;
6. The vehicle surrounding photographing apparatus according to claim 5, further comprising a switching unit that switches between the first storage unit and the second storage unit.

Images