JPH0935198A - Traveling road detector for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve white line detecting processing speed by binarizing the picture of a road extended ahead of a vehicle, linearly approximating plural white line positions detected within the searching range in the picture and setting up the searching range in accordance with the approximated result. SOLUTION: A road picture F of a road extended ahead of a driver's own vehicle which is photographed by a video camera (forward photographing part) 1 loaded on the vehicle is inputted to an edge extracting part 2, an edge component is binarized by a prescribed threshold and converted into an edge picture G. A prescribed scanning line existing on the lower part of the picture G is set up as a scanning start position for detecting a white line L, a searching range setting part 3 sets up a searching range H for practically searching the white line L on a current scanning line, a white line detecting part 4 applies linear approximation to plural white line positions detected within the searching range H, and the setting means 3 sets up the range H in accordance with the linear approximation result in a part of the area for detecting the while line L. Since the searching range H is optionally set up, white line searching processing time can be shortened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for detecting a road ahead of an own vehicle by using image processing technology for preventive safety of a running vehicle, and more particularly to surely preventing erroneous detection of a white line on the road. The present invention relates to a vehicle traveling road detection device having improved reliability.

[0002]

2. Description of the Related Art Conventionally, a vehicle traveling road detecting device using an in-vehicle video camera (forward photographing means) and an image processing means is well known. For example, an edge of a photographed road image is utilized. As a device for detecting a white line, there is one disclosed in Japanese Patent Application Laid-Open No. 5-166096. In the vehicle traveling road detection device described in this publication, as shown in FIG. 12, an edge E, which is an intersection point when scanning from the lower part of the image to the left and right, is found and set as the position of the white line L. Search upwards in the image.

As a method for searching for a white line, as shown in FIG. 13, a white line searching window W is set on the image according to the white line detection result, and this window W is set.
There is also a method of searching for the white line L among them, and this method is disclosed in Japanese Patent Laid-Open No.
It is disclosed in Japanese Patent Publication No. 303625. Further, as described in JP-A-5-347000, there is a method in which the detected white line is linearly approximated and the set position and size of the white line search window are dynamically changed according to the approximation result.

Further, as described in Japanese Patent Laid-Open No. 6-225308, past white line detection results, vehicle speed, and steering angle are obtained by complicated arithmetic processing, and the shape of the white line is estimated based on this. After that, a method of changing the search range of the white line according to the shape of the white line is also proposed.

[0005]

As described above, the conventional vehicle running road detecting device is effective in increasing the processing speed in setting the white line search area, but it is not suitable for various shapes of the actual white line. Since it is necessary to set the search range so as to be compatible, there is a problem that the algorithm is complicated and the processing takes time, and the effect of speeding up the processing by limiting the search area cannot be obtained.

Further, in the conventional vehicle running road detecting device, when the white line is not well detected for some reason, the reliability of the detection result becomes low, or the input image changes remarkably due to a lane change or the like. Since there is no means for coping with the problem, for example, once the white line detection becomes unstable and many white line erroneous detections occur, it is difficult to return to the normal detection state and the response of the detection deteriorates.

The present invention solves the above problems, and provides a vehicle running road detecting device which can deal with the shape of a white line on an actual road image such as a curved road and has a high processing speed. With the goal.

Further, according to the present invention, when a situation in which the white line detection performance is deteriorated for some reason is detected, the white line position is temporarily fixed to a predetermined road shape so that the white line is erroneously detected. It is an object of the present invention to provide a vehicle traveling path detection device that reduces the influence and is quick to recover from erroneous detection and has high accuracy.

[0009]

According to a first aspect of the present invention, there is provided a vehicle traveling road detecting device which is mounted on a vehicle and which is used for binarizing the road image and a front photographing means for photographing a road image in front of the vehicle. An image binarization unit, a white line detection unit that detects a white line from the binarized image, and a search range setting unit that sets a search range for detecting the white line, and the white line detection unit is within the search range. Having a linear approximation means for performing a linear approximation with respect to a plurality of white line positions detected by, and the search range setting means sets the search range according to the linear approximation result in a part of the area where the white line is detected. Is.

Further, according to a second aspect of the present invention, there is provided a vehicle traveling road detecting device, which is mounted on a vehicle to photograph a road image in front of the vehicle, and a road image which is a binarized image. The search range includes a binarization unit, a white line detection unit that detects a white line from the binarized image, and a search range setting unit that sets a search range for detecting the white line, and a navigation that outputs road shape information is provided. The setting means sets the search range according to the road shape information.

According to a third aspect of the present invention, there is provided a vehicle traveling road detection device which is mounted on a vehicle and which is used for photographing a road image in front of the vehicle, and a road image which is a binarized image. A binarizing means, a white line detecting means for detecting a white line from the binarized image, and a search range setting means for setting a search range for detecting the white line, the search range setting means is a binary value within the search range. The distance from the vehicle to the white line is calculated based on the position of the white line on the converted image, and the search range is set according to the calculated distance.

Further, according to a fourth aspect of the present invention, there is provided a vehicle traveling road detecting apparatus which is mounted on a vehicle and which is used for photographing a road image ahead of the vehicle, and a road image which is a binarized image. A steering angle sensor means for detecting the steering angle of the vehicle is provided, which comprises a binarizing means, a white line detecting means for detecting a white line from the binarized image, and a search range setting means for setting a search range for detecting the white line. The search range setting means is provided to set the search range according to the steering angle.

According to a fifth aspect of the present invention, there is provided a vehicle traveling road detecting device which is mounted on a vehicle and which is used for photographing a road image ahead of the vehicle, and a road image which is a binarized image. The search range setting means includes a binarizing means, a white line detecting means for detecting a white line from the binarized image, and a search range setting means for setting a search range for detecting the white line. The search range is set wide when the undetected situation continues for a predetermined period.

According to a sixth aspect of the present invention, there is provided a vehicle traveling road detecting device which is mounted on a vehicle and which is used as a forward photographing means for photographing a road image ahead of the vehicle. Quantization means and white line detection means for detecting a white line from the binarized image, vehicle speed sensor means for detecting the vehicle speed of the vehicle is provided, the white line detection means, when the vehicle speed is determined to be low, other In order to avoid erroneous detection of the background including surrounding vehicles, a white line position fixing means for fixing the position of the white line in accordance with a predetermined road shape is provided.

According to a seventh aspect of the present invention, there is provided a vehicle traveling road detecting device which is mounted on a vehicle and which is used for photographing a road image ahead of the vehicle, and a road image which is a binarized image. The white line detecting means for detecting the white line from the binarized image is provided, and the white line detecting means adjusts the white line position to a predetermined road shape when a large number of white line candidates exist and the white line position cannot be specified. It has a white line position fixing means for fixing.

[0016] According to a eighth aspect of the present invention, there is provided a vehicle traveling road detecting device which is mounted on a vehicle and which takes forward road photographing means for photographing a road image ahead of the vehicle. The white line detecting means for detecting the white line from the binarized image is provided, and the wiper detecting means for detecting the operating state of the wiper of the vehicle is provided.The white line detecting means detects that the wiper is operating. In this case, a white line position fixing means is provided for fixing the position of the white line in accordance with a predetermined road shape.

According to a ninth aspect of the present invention, there is provided a vehicle traveling road detecting device which is mounted on a vehicle and which is used as a forward photographing means for photographing a road image in front of the vehicle. A binarizing means and a white line detecting means for detecting a white line from the binarized image are provided, and a winker detecting means for detecting blinking of the winker of the vehicle is provided. The white line detecting means detects blinking of the winker by the winker detecting means. Alternatively, when the position of the white line changes significantly, the lane change detection means that determines that the vehicle is undergoing a lane change, and the position of the white line when the vehicle is determined to be undergoing a lane change by the lane change detection means It has a white line position fixing means for fixing in accordance with a predetermined road shape.

According to a tenth aspect of the present invention, there is provided a vehicle traveling road detecting device which is mounted on a vehicle and which is used for photographing a road image ahead of the vehicle, and a road image which is a binarized image. It comprises a binarizing means and a white line detecting means for detecting a white line from the binarized image, and the white line detecting means temporarily positions the white line on a predetermined road when a situation in which the white line is not detected continues for a predetermined period. It has a white line position fixing means for fixing according to the shape.

According to an eleventh aspect of the present invention, there is provided a vehicle running road detecting apparatus according to any one of the sixth to tenth aspects, wherein the white line position fixing means detects the position of the white line most immediately before. The white line is fixed at the position.

According to a twelfth aspect of the present invention, there is provided a vehicle traveling road detecting apparatus according to any one of the sixth to tenth aspects, further comprising steering angle sensor means for detecting a steering angle of the vehicle. The fixing means fixes the position of the white line according to the steering angle obtained by the steering angle sensor means.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1. Embodiment 1 of the present invention will be described below with reference to the drawings. 1 is a block diagram showing a schematic configuration of a first embodiment of the present invention. In the figure, reference numeral 1 denotes a front photographing section including a video camera mounted on a vehicle, and photographs a road image F in front of the vehicle. Reference numeral 2 denotes an edge extraction unit that obtains an edge image G from the road image F photographed by the front photographing unit 1, detects an edge having a large luminance change from the road image F, and obtains the edge image G as a binarized image. It constitutes the value-converting means.

Reference numeral 3 is a search range setting section for setting a search range H (scanning area) for detecting a white line from the edge image G, 4 is a white line detecting section for detecting a white line L from the edge image G within the search range H, and 5 is a white line detecting section. The result output unit displays the detection result of the white line L on the road image F.

Reference numeral 6 is a steering angle sensor for detecting a steering angle θ by a driver who steers the vehicle, and 7 is a navigation for outputting map information, that is, road shape information D. These steering angle θ and road shape information D
Are input to the search range setting unit 3 together with the edge image G.

Next, the flowchart of FIG. 2 and FIG.
The schematic operation of the first embodiment of the present invention shown in FIG. 1 will be described with reference to the explanatory view of FIG. FIG. 2 shows the flow of the traveling road detection processing in the first embodiment of the present invention.
FIG. 11A shows an example of the edge image G.

In FIG. 11A, 111 is a scanning line indicating the scanning start position in the edge image G, L1 is a white line position detected as an intersection of the scanning line 111 and the white line L, and Li is each scanning line and white line. The white line position detected as the intersection with L, the arrow 113 is the moving direction of the scanning position, 11
Reference numeral 4 is a preceding vehicle traveling in front of the host vehicle.

First, the road image F photographed by the front photographing unit 1 is input to the edge extraction unit 2 and the edge component is binarized by a predetermined threshold value, so that an edge as shown in FIG. The image G is converted. Here, the predetermined scanning line 111 below the edge image G is set as the scanning start position for detecting the white line L (step S101).

Subsequently, the search range setting unit 3 sets a search range H for actually searching for the white line L on the current scanning line 111 (step S102). In addition,
The setting operation of the search range H (step S102) by the search range setting unit 3, which is a major feature of the present invention, will be described later in detail.

Next, the white line detecting section 4 searches in the left and right direction for an edge that is considered to be the white line L on the current scanning line 111 within the search range H set in the search range setting step S102, and finds the detected edge. Is the white line position L1
Is detected (step S103).

The search range setting step S102 and the white line position detecting step S103 described above are repeated while updating the scanning position from the lower side to the upper side of the edge image G (step S104) as shown by an arrow 113 in FIG. .

That is, the scanning position updating step S104
Then, it is determined whether or not the scanning has been completed for all the white line detections (step S105). If it is determined that it is not completed (that is, NO), step S102.
, And all white line detection is completed (that is, Y
If ES) is determined, the process proceeds to the next step S106.

After the white line detection end (YES) is determined in step S105, a plurality of white line positions L1 are detected.
The straight line approximation of the white line L is performed based on the detection points of ~ Li (step S106). The above is the outline of the white line L detection operation (traveling road detection operation).

Next, the flowchart of FIG. 3 and FIGS.
Embodiment 1 of the present invention with reference to the explanatory view of FIG.
Details of the search range setting step S102 will be described. FIG. 4 shows an edge image G displaying a white line L, an arrow H in the horizontal direction (the coordinate value increases as it is located in the right direction), and an arrow V in the vertical direction (the coordinate value increases as it is located in the downward direction). ). R is an area for detecting the white line L, and is divided into two upper and lower areas RA and R.
B. Vpa is a division point of each of the regions RA and RB.

FIG. 5 is an explanatory view showing the search range H for the white line L in the area RA, and LD is a straight line approximated by a linear expression based on the position of the white line detected in the area RA. FIG. 6A is an explanatory diagram showing a vehicle C that follows the white line L on a curved road in XY plane coordinates, and LC indicates a white line L (curve) on the X axis at the current position of the vehicle C. The tangent line and the Y-axis are the traveling directions of the vehicle C. FIG. 6B is an explanatory diagram showing the relationship of the search range H set according to the magnitude of the steering angle θ of the vehicle C, where θth is a threshold value of the steering angle θ, that is, a comparison reference value, and HS is a small search range. HL is a large search range.

FIG. 7A is an explanatory view showing the position and traveling direction (arrow) of the vehicle C on the road shape information (map) D, and FIG. 7B is seen from the front photographing section 1 on the vehicle C. It is explanatory drawing which shows the edge image G of a front road. In FIG. 7A, QR1 to QRn and QL1 to QLn are road shape information D.
These are the upper road edge positions, QR1 to QRn are the right road edge positions seen from the vehicle C, and QL1 to QLn are the left road edge positions. In addition, in FIG. 7B, PR1 to PRn
And PL1 to PLn are road edge positions in the edge image G, PR1 to PRn are right road edge positions as viewed from the vehicle C, and PL1 to PLn are left road edge positions.

Generally, the white line L displayed on the edge image G has a linear shape in the lower area RA in the edge image G and the upper area R in the edge image G as shown in FIG.
B often shows a curved shape. A region R in which the white line L is detected in order to correspond to the shape of the white line L as shown in FIG.
Is divided into two regions, a region RA including a linear portion of the white line L and a region RB including a curved portion, via a division point Vpa.

Therefore, in the processing flow of FIG.
The method of setting the search range H of the white line L by the search range setting unit 3 differs depending on whether the position Vp of the scanning line (hereinafter referred to as the scanning position) is located above or below the division point Vpa. That is, first, it is determined whether or not the coordinates of the scanning position Vp are larger than the coordinates of the division point Vpa (positioned below the division point Vpa) (step S20).
1).

If, in step S201, the scanning position Vp is larger than the division point Vpa (that is, YES).
If it is determined that the white line L cannot be continuously detected, it is determined (step S202). if,
The state where the white line L is not detected continuously (that is, YE
If it is determined to be S), the search range (width) H is widened (step S203) and the process proceeds to step S103.

On the other hand, in step S202, the white line L
Is determined to be a detectable state (that is, NO),
The position of the straight line LD obtained by the previously obtained linear approximation formula is set as the center position of the search range H (step S
204). Then, the search range H is set by the scanning position Vp, and the search range (width) H is set narrower as the distance from the host vehicle to the white line L increases (step S20).
5). As a result, the search range H as shown in FIG. 5 is set.

This is because, when a certain object is projected on the edge image G, it is necessary to consider the principle that the width of the object is displayed smaller as the distance from the host vehicle increases. For example, the width of the white line L is actually constant, but the width of the white line L displayed in the edge image G becomes narrower as the distance from the host vehicle increases, so the search range H is also set to be narrow. It will be.

The straight line LD in FIG. 5 is obtained by the straight line approximation step S106 (see FIG. 2), and the straight line approximation at this time is executed using only the white line detection points detected in the area RA. . Here, for example, a method of approximating the straight line LD by the least square method will be briefly described as an example.

First, the scanning position Vi (i = 1) in the area RA
˜n), an approximate expression of the straight line LD obtained by using the white line position Li (i = 1 to n) detected on is expressed as follows as a linear expression on the xy coordinates.

Y = ax + b

The slope a and the y intercept b on the straight line LD in the above equation
Is obtained by the following equations (1) and (2).

A = {(ΣLi) (ΣVi) −n · Σ (Li · Vi)}
/ {(ΣLi) ² −n (ΣLi ² )} (1) b = {ΣVi−a (ΣLi)} / n (2)

However, in the summation terms in the expressions (1) and (2), i = 1, 2, ..., N. On the other hand, in step S201, if the scanning position Vp is located above the division point Vpa and it is determined that Vp ≦ Vpa (that is, NO), the value of the steering angle θ input from the steering angle sensor 6 is determined. A comparison is made with the reference value θth to determine whether the steering angle θ is larger than the comparison reference value θth (step S206).

If the steering angle θ is the comparison reference value θt
If it is determined to be larger than h (that is, YES),
The search range H is set to a large fixed value HL to widen the search range H (step S207). On the other hand, if it is determined that the steering angle θ is equal to or smaller than the comparison reference value θth (that is, NO), the search range H is set to a small fixed value HS to narrow the search range H (step S208).

FIG. 6A shows a state in which the vehicle C (own vehicle) traveling along the Y-axis in the middle of the curved road (origin) is viewed from above, and the steering angle θ of the vehicle C is the vehicle C. When the origin is set, the tangent line LC of the white line L passing through the X axis and the vehicle C
Is the angle formed by the traveling direction (Y axis) of the.

For example, as shown in FIG. 6B, if the steering angle θ is larger than the comparison reference value θth, the search range (width) H is a value HL (> HS) larger than HS.
(Step S207), if the steering angle θ is smaller than the comparison reference value θth, the search range (width) H
Is fixed to a small value HS (step S208).

Thus, after fixing the search range (width) H according to the steering angle θ, the map information, that is, the road shape information D is converted into the position on the edge image G, and the white line position L is obtained.
i is estimated and set as the center position of the search range H (step S209). FIG. 7 specifically shows this state.

In FIG. 7 (a), if the vehicle C is moving in the traveling direction of the arrow on the road shape information D (map), the right road edge position QRn and the left road edge QLn.
Are converted into road edge positions PRn and PLn on the edge image G of FIG.
It becomes the center position of.

As described above, by limiting the area for searching the white line L from the road image F in front of the host vehicle, that is, the search range H, high-speed processing of the road image can be realized. Further, by setting the search range H corresponding to the actual road shape on the road image F such as a curved road, it is possible to detect the white line L of the curve.

Furthermore, if the white line L cannot be detected or the detected value of the white line L becomes unstable for some reason, this is detected and the position of the white line L is temporarily set to a predetermined road shape. By fixing to, it is possible to speed up recovery from erroneous detection. As a result, more accurate and reliable white line detection with high processing speed can be realized.

Embodiment 2 Although the search range H in the edge image G is set according to the steering angle or the road shape information D in the first embodiment, the white line L in the edge image G is directly detected according to various sensor information. May be. FIG. 8 is a block diagram showing a configuration of a vehicle travel road detection device according to a second embodiment of the present invention which detects a white line in accordance with various sensor information.
4 corresponds to the white line detection unit 4, which is 1, 2, 5, 6,
F, G, L and θ are the same as described above.

Reference numeral 85 is a vehicle speed sensor for detecting the vehicle speed A, and 87
Is a wiper switch that outputs a wiper signal B, and 88 is a winker switch that outputs a winker signal U. The vehicle speed A, the wiper signal B, and the winker signal U are input to the white line detection unit 84 together with the steering angle θ. . Wiper switch 85 and winker switch 87
Cooperates with the white line detection unit 84 to configure wiper detection means and winker detection means. In this case, the navigation 7 and the search range setting unit 3 described above (FIG. 1) are unnecessary.

Next, the operation of the second embodiment of the present invention will be described with reference to the flowchart of FIG.
FIG. 9 shows a processing flow of the white line detection unit 84 in FIG.
303 corresponds to the white line position detection step S103, and S101 and S105 are the same steps as described above.

First, the road image F photographed by the front photographing section 1 is input to the white line detecting section 84 as an edge image G in which the edge component is extracted by the edge extracting section 2 as described above. The white line detection unit 84, as shown in FIG.
The scanning line 111 located below the edge image G is used as a start line for detecting the white line L (step S
101), the scanning line 111 is scanned in the left-right direction from the center of the screen to detect the position of the white line L (step S303).

Subsequently, it is determined whether or not the scanning for detecting the white line L is completed (step S105), and if it is determined that the scanning is not completed (that is, NO),
After updating the scanning position (step S304), the process returns to step S303. As a result, the scanning position is shown in FIG.
While updating from the bottom to the top like the arrow 113 inside,
Step S303 is repeated to detect a plurality of white line positions. On the other hand, if it is determined in step S105 that scanning has ended (that is, YES), the result output unit 5 outputs the white line detection result (step S305).

Next, the details of the white line position detecting step S303 in FIG. 9 will be described with reference to the flowchart of FIG. In FIG. 10, S206 is the same step as described above (FIG. 3). First, the vehicle speed A input from the vehicle speed sensor 85 is compared with a reference value (threshold value) Ath,
It is determined whether the vehicle speed A is higher than the comparison reference value Ath (step S401).

This is because when the vehicle speed A is low, other stopped vehicles and background noise may be erroneously detected as the white line L.
This is because it is necessary to confirm that the vehicle speed A is high to some extent in order to obtain sufficient detection reliability of the white line L.

If it is determined that the vehicle speed A is larger than the comparison reference value Ath (that is, YES), then it is determined whether the steering angle θ is smaller than the comparison reference value θth (step S402). If it is determined that θ <θth (that is, YES), it is further determined whether or not the wiper is stopped (wiper signal B is OFF) (step S403).

If the wiper is stopped (that is, YE
If it is determined to be S), the white line L on the scanning line is searched in the left-right direction (step S404). This is done by examining the following three conditions (a) to (b) (all of which are conditions for removing an element that causes an erroneous detection of a white line) based on each of the determination steps S401 to S403 and satisfying all of them. It means that the white line L on the scanning line is searched for in the left-right direction (step S404) only when it is present.

(A) The vehicle is running at a high speed in which the vehicle speed A is larger than the comparison reference value Ath (step S401). (B) The steering angle θ is smaller than the comparison reference value θth and the vehicle is traveling stably (step S402). (C) The wiper is not moving (step S40)
3).

On the other hand, if any one of the above conditions (a) and (b) is not satisfied, a reliable white line L is obtained.
It is determined that the white line L cannot be detected, and the white line L
The process proceeds to step S206 for fixing the position of No. to a predetermined value. That is, it is determined whether or not the steering angle θ is larger than the comparison reference value θth (step S206). If θ> θth (that is, YES), the change from the previous time is large. The white line position is fixed to the road turning position estimated by (step S4
11), if θ ≦ θth (that is, NO), the white line position is fixed to the road shape position detected immediately before (step S412).

After the white line search step S404, the process proceeds to step S405 and subsequent steps, where the white line position fixing process is performed according to the determination result of the position detection status of the white line L. First, it is determined whether the edge position of the white line L (probably) detected in step S404 has largely moved from the previous detection position (step S405). If the edge position this time has moved significantly (that is, YES)
If it is determined that the winker is stopped (whether the winker signal U is OFF), it is then determined (step S40).
6).

If the blinker is blinking (that is,
If NO is determined, the edge position is largely moved (step S405) and the blinker is blinking (step S4).
06), and it is determined that the reliable white line cannot be detected because the own vehicle is undergoing lane change (lane change). Therefore, in order to fix the white line position to a predetermined value, the steering angle determination step S206
Proceed to.

FIG. 11B is an explanatory view showing an example of the edge image G ahead of the own vehicle during the lane change, 114 and L.
And Li are the same as described above. During the lane change of FIG. 1B, the position of the white line L on the edge image G moves significantly compared to the normal state of FIG. 11A, so the detected white line position Li is also as shown in the figure. It moves greatly.

In the edge position movement judging step 405,
The feature of the change of the edge image G in the lane change as shown in FIG. 11B is used, and by fixing the white line position as in steps S411 and S412,
False detection of the white line L can be prevented.

Here, not only the large movement of the edge position (step S405) but also the condition (step S406) for judging whether or not the blinker blinks is added to enable more reliable judgment. However, step S4
The white line position fixing steps S206, S411, and S412 based on only one of the conditions of 05 and S406.
You may proceed to.

On the other hand, if it is determined in step S405 that the edge position has not moved largely (that is, NO), or if it is determined in step S406 that the winker signal U is OFF (that is, YES), Then, the presence or absence of the white line L is determined (step S40).
7). If the white line L is not detected (that is, NO)
If it is determined that the white line L is continuously in a non-detection state for a predetermined time (step S
408), if continuous (that is, YES), the process proceeds to step S206.

As described above, the white line L is searched for in step S404, and the presence or absence of the white line L is determined in step S407. As a result, it is in a state where an edge thought to be the white line L cannot be found (that is, NO), and in step S408. When it is determined that this state continues (that is, YES), it is considered that the white line does not exist, and the position of the white line L is fixed to a predetermined value (steps S206 and S41).
1, S412).

Furthermore, when there are a large number of edge candidate points on the scan line when searching for the edge position in the left-right direction on the scan line, in order to prevent erroneous detection of the white line L,
The following determination process is performed. That is, step S40
When it is determined that there is a white line in step 7 (that is, YES) or when the state of no white line is discontinuous (that is, NO) in step S408, the total sum Esum of the detected edges is the comparison reference value Eth. It is determined whether or not it is less than (step S409).

If Esum ≧ Eth (that is, N
If it is determined to be O), it is considered that the detection reliability of the white line L has decreased, and the position of the white line L is fixed to a predetermined value (steps S206, S411, S412). Also, Esum <
If it is determined to be Eth (that is, YES), the position of the detected white line L, or step S411 or S4.
The white line position is determined at the position fixed at 12 (step S413).

As described above, the second embodiment of the present invention
The white line position detection processing by step S401 to S40
When the condition of No. 3 is not satisfied and it is determined that the white line L cannot be detected, the setting method for fixing the value of the white line position is switched according to the steering angle θ.

That is, if θ> θth, the curve of the road is calculated from the steering angle θ, and this is calculated as the edge image G.
The white line position is fixed to the position estimated by the above conversion (step S411), and if θ ≦ θth, the current white line position is fixed to the previously detected white line position (step S41).
2).

In addition, in steps S405 to S409, the white line position is fixed to a predetermined value when it is determined that the white line L cannot be detected, and otherwise, the edge position found when searching in the horizontal direction on each scanning line. Is detected as the white line position, and the white line position is determined (step S41).
3). By detecting the white line L by such an algorithm, it is possible to prevent frequent occurrence of erroneous detection of the white line L and obtain a vehicle travel path detection device that recovers quickly from the erroneous detection.

[0076]

As described above, according to the present invention, the search range when searching for a white line can be arbitrarily set, so that the processing time for searching for a white line can be shortened and the white line can be detected. There is an effect that a vehicle traveling road detection device capable of speeding up is obtained.

Further, according to the present invention, a straight line is approximated from a plurality of detected white line positions, and the white line search range is set by a linear approximation formula in a part of the area where the white line is detected. There is an effect that a vehicle running road detection device that can more accurately detect a white line shape on an image that also has linear components is obtained.

Further, according to the present invention, since the search range for white line detection is set according to the road shape information obtained by the navigation, the white line shape on the image having both the curved line component and the straight line component is formed. It is possible to set a combined search range, and to obtain a vehicle travel road detection device capable of highly accurate white line detection.

Further, according to the present invention, the search range for detecting the position of the white line is set according to the distance to the host vehicle of the white line calculated from the scanning position on the image, and varies depending on the distance from the host vehicle to the white line. Since the width of the object on the image can be dealt with, it is possible to obtain the vehicle travel path detection device with less processing error and high processing speed.

Further, according to the present invention, since the steering angle sensor for detecting the steering angle (steering angle) of the vehicle is provided and the search range is set to the predetermined value according to the steering angle, the white line is not bent. The search range can be set accordingly, and complicated calculations for estimating the white line position and the curve on the image from the steering angle, which only set a predetermined value, are unnecessary, and the processing speed is fast and highly accurate white line detection can be performed. There is an effect that the traveling road detection device for a vehicle can be obtained.

Further, according to the present invention, when the white line cannot be detected during the white line search, the search range for detecting the white line is widened so that the white line does not exist on the image. Even in the undetectable state, the white line can be immediately detected when the white line appears on the image again, and there is an effect that the vehicle traveling path detection device having a high adaptability to the background change can be obtained.

Further, according to the present invention, the driving situation in which the erroneous detection of the white line is likely to occur is detected, the decrease in the reliability of the white line detection is judged, and the reliable white line detection is impossible. When the judgment is made, the white line position is fixed to the predetermined road shape, so that the occurrence of erroneous detection is reduced, and a vehicle running road detection device that recovers quickly from erroneous detection or undetectable state is obtained. It is effective.

Further, according to the present invention, when it is determined that the reliable white line cannot be detected, the set white line position is set to the road shape detected immediately before, so that the white line cannot be detected well. There is an effect that the error of the detection result at the time is minimized, and a vehicle traveling path detection device that recovers from erroneous detection faster is obtained.

Further, according to the present invention, when it is determined that reliable white line detection is impossible, the white line position to be set is set according to the steering angle, and the white line position on the image such as the bending angle changes greatly. Even in situations where
Since the position of the white line can be estimated from the steering angle, the error in the detection result when the white line cannot be detected well can be minimized, and the vehicle running road detection device can recover more quickly from the false detection. There is.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a first embodiment of the present invention.

FIG. 2 is a flowchart showing an outline of a white line detection processing operation according to the first embodiment of the present invention.

FIG. 3 is a flowchart showing a search range setting processing operation according to the first embodiment of the present invention.

FIG. 4 is an explanatory diagram showing an example of a white line detection area in a search range setting process according to the first embodiment of the present invention.

FIG. 5 is an explanatory diagram showing an example of search range setting processing of a straight line approximation portion of a white line according to the first embodiment of the present invention.

FIG. 6 is an explanatory diagram showing an example of setting the search range of the white line from the steering angle in the search range setting processing according to the first embodiment of the present invention.

FIG. 7 is an explanatory diagram showing an example of setting a white line search range from navigation road shape information in the search range setting process according to the first embodiment of the present invention, in which (a) is a positional relationship on a map; (B) shows the positional relationship on the edge image.

FIG. 8 is a block diagram showing a schematic configuration of a second embodiment of the present invention.

FIG. 9 is a flowchart showing an outline of a white line detection processing operation according to the second embodiment of the present invention.

FIG. 10 is a flowchart showing a white line position detection processing operation according to the second embodiment of the present invention.

FIG. 11 is an explanatory diagram showing a white line detection operation according to the first and second embodiments of the present invention, in which (a) is a white line position detected for each scanning line in a normal state,
(B) shows the position of the white line on the edge image in the lane change state.

FIG. 12 is an explanatory diagram showing a white line detection operation by the conventional vehicle road detection device disclosed in Japanese Patent Laid-Open No. 5-166096.

FIG. 13 is an explanatory diagram showing a window setting operation by the conventional vehicle travel road detection device disclosed in Japanese Patent Laid-Open No. 5-303625.

[Explanation of symbols]

1 frontal imaging section, 2 edge extraction section (binarization means), 3
Search range setting unit, 4, 84 white line detection unit, 6 steering angle sensor, 7 navigation, 85 vehicle speed sensor, 87 wiper switch, 88 winker switch,
111 scanning start position, 113 scanning position movement direction, 1
14 preceding vehicle, A vehicle speed, B wiper signal, C vehicle (own vehicle), D road shape information, F road image, G edge image (binarized image), H search range, L white line,
LD Approximated straight line, L1, Li white line position (white line detection point), R, RA, RB white line detection area, U winker signal, θ steering angle, S102 Step for setting search range, S202 White line cannot be detected Step, S203 setting a wide search range, S205 setting a search range according to a distance, S206 comparing a steering angle with a reference value, S207, S208 fixing a search range, S401 determining a vehicle speed Step, S
403 Step for determining during wiper operation, S404
Steps of searching for a white line in the left-right direction, S405, a step of determining the movement of the edge position, S406, a step of determining that the blinker is operating, S409, a step of determining the number of white line candidates, S411, S412 a step of fixing the white line position.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location G06T 7/00 G06F 15/62 380 G08G 1/0962 9061-5H 15/70 330G

Claims (12)

[Claims] 1. A front photographing means mounted on a vehicle for photographing a road image ahead of the vehicle, a binarizing means for converting the road image into a binarized image, and a white line detected from the binarized image. In the vehicle running road detection device comprising a white line detecting means for setting and a search range setting means for setting a search range for detecting the white line, the white line detecting means includes a plurality of white lines detected in the search range. It has a linear approximation means for performing a linear approximation to the position of the white line, the search range setting means sets the search range according to the linear approximation result in a part of the area for detecting the white line. Vehicle road detection device. 2. A front photographing means mounted on a vehicle for photographing a road image ahead of the vehicle, a binarizing means for converting the road image into a binarized image, and a white line detected from the binarized image. In the vehicle running road detection device including the white line detecting means and the search range setting means for setting the search range for detecting the white line, a navigation for outputting road shape information is provided, and the search range setting means is The vehicle running road detection device, wherein the search range is set according to the road shape information. 3. A front photographing means mounted on a vehicle for photographing a road image ahead of the vehicle, a binarizing means for converting the road image into a binarized image, and a white line detected from the binarized image. In the vehicular traveling road detecting device, the vehicle includes a white line detecting means for detecting the white line, and a search range setting means for setting a search range for detecting the white line, wherein the search range setting means includes the binarization in the search range. A vehicle traveling road detection device, characterized in that a distance from the vehicle to the white line is calculated based on a position of the white line on an image, and the search range is set according to the calculated distance. 4. A front photographing means mounted on a vehicle for photographing a road image ahead of the vehicle, a binarizing means for converting the road image into a binarized image, and a white line detected from the binarized image. In the vehicle running road detection device, which includes a white line detection means for performing a white line detection, and a search range setting means for setting a search range for detecting the white line, a steering angle sensor means for detecting a steering angle of the vehicle is provided, The vehicle travel path detection device, wherein the search range setting means sets the search range according to the steering angle. 5. A front photographing means mounted on a vehicle for photographing a road image ahead of the vehicle, a binarizing means for converting the road image into a binarized image, and a white line detected from the binarized image. In the vehicle running road detection device, the white line detecting means for detecting the white line, and the search range setting means for setting a search range for detecting the white line, wherein the search range setting means detects the white line in the search range. A vehicle travel path detection device, characterized in that the search range is set to be wide when a situation in which the operation is not performed continues for a predetermined period. 6. A front photographing means mounted on a vehicle for photographing a road image ahead of the vehicle, a binarizing means for converting the road image into a binarized image, and a white line detected from the binarized image. In the vehicle traveling road detection device having the white line detecting means, the vehicle speed sensor means for detecting the vehicle speed of the vehicle is provided, and the white line detecting means is used when the vehicle speed is determined to be low. In order to prevent erroneous detection of the background including the white line, the vehicle has a white line position fixing means for fixing the position of the white line in accordance with a predetermined road shape. 7. A front photographing means mounted on a vehicle for photographing a road image ahead of the vehicle, a binarizing means for converting the road image into a binarized image, and a white line detected from the binarized image. In the vehicle running road detection device having a white line detecting means, the white line detecting means fixes the white line position according to a predetermined road shape when the white line position cannot be specified due to a large number of white line candidates. A vehicle running road detection device having a white line position fixing means. 8. A front photographing means mounted on a vehicle for photographing a road image ahead of the vehicle, a binarizing means for converting the road image into a binarized image, and a white line detected from the binarized image. In the vehicle traveling road detection device having a white line detecting means, a wiper detecting means for detecting an operating state of the wiper of the vehicle is provided, and the white line detecting means detects when the wiper is operating. In addition, the vehicle running road detecting device is characterized by further comprising white line position fixing means for fixing the position of the white line in accordance with a predetermined road shape. 9. A front photographing means mounted on a vehicle for photographing a road image ahead of the vehicle, a binarizing means for converting the road image into a binarized image, and a white line detected from the binarized image. In the vehicle running road detection device having a white line detecting means, a blinker detecting means for detecting blinking of the blinker of the vehicle is provided, and the white line detecting means detects whether the blinker of the blinker is detected by the blinker detecting means. , Or a lane change detecting means for determining that the vehicle is undergoing a lane change when the position of the white line changes significantly, and the lane change detecting means determines that the vehicle is undergoing a lane change, A vehicle running road detection device, comprising: a white line position fixing means for fixing the position of the white line in accordance with a predetermined road shape. 10. A front photographing means mounted on a vehicle for photographing a road image ahead of the vehicle, a binarizing means for converting the road image into a binarized image, and a white line detected from the binarized image. In the vehicle traveling road detecting device having a white line detecting means, the white line detecting means fixes the position of the white line in accordance with a predetermined road shape when a situation in which the white line is not detected continues for a predetermined period. A vehicle running path detection device having a white line position fixing means. 11. The vehicle according to any one of claims 6 to 10, wherein the white line position fixing means fixes the position of the white line to the position of the white line detected most recently. Road detection device. 12. Steering angle sensor means for detecting a steering angle of the vehicle is provided, and the white line position fixing means fixes the position of the white line according to the steering angle obtained by the steering angle sensor means. Claims 6 to 1 characterized by
The vehicle travel path detection device according to any one of 0 to 5.