DE102013014967A1 - Driver assistance system for a motor vehicle - Google Patents

Abstract

In a driver assistance system comprising a camera system (2) monitoring a solid angle (4) and comprising at least one camera, a display screen (3), an image transformation unit (5) for transforming raw images of the camera system (2) into display images (12) and outputting of the display images (12) on the display screen (3), the image transformation unit (5) is arranged to decide for a sector (16) of the solid angle (4) whether or not it contains a vehicle-related object (15) and the extent of this Sector (16) corresponding image area in a display image (12) on the basis of the result of the decision.

Description

The present invention relates to a driver assistance system having a camera system that monitors a solid angle for a motor vehicle.

In future, according to the ECE standard in motor vehicles for detecting the past traffic, camera systems with a display screen for image display will be permitted. These camera systems can replace the exterior mirrors and rear view mirrors in the future.

When using conventional exterior mirrors and rear-view mirrors, the phenomenon of blind spot is known. That is, an area adjacent to the motor vehicle is neither visible on the exterior mirror nor on the rearview mirror. This area can be viewed by the driver at most by a strong twisting of the head and the body. Replacing the exterior mirror with a camera that uses a simple lens to capture the surroundings next to and behind the vehicle, and a display for image display uses the same effect.

Motor vehicle exterior mirrors are therefore often made in two parts or with curved surfaces in order to reduce the blind spot. Mirror images on the curved mirror surface appear reduced and distorted; this makes it difficult to quickly detect items and correctly estimate their distance from the vehicle.

DE 600 29 335 T2 describes a camera system for detecting a 180 ° room angle behind a motor vehicle. This is equipped with two cameras and an image processing system, which composes the raw images of the two cameras to a clear as possible distortion-free display image. When used as an exterior mirror, the true-to-scale, clear representation of the recorded solid angle of about 180 °, however, requires an oversized display. The driver's important area behind the vehicle occupies only a small portion of this display, so important details can be overlooked. While objects behind the vehicle may also be relevant for driver decisions at a great distance, objects located laterally from the vehicle at a distance of more than one lane width are typically not. In a distortion-free display image, these latter objects occupy a disproportionately large space in relation to their meaning and can thereby irritate the driver.

Object of an embodiment of the invention is to make a driver assistance system with a camera system so that it can be used as an exterior or rear view mirror and the driver allows a quick and reliable assessment of the traffic behind his vehicle and laterally from this.

The object is achieved by a driver assistance system having a camera system which monitors a solid angle and comprises at least one camera, a display screen, an image transformation unit for transforming raw images of the camera system into display images and outputting the display images to the display screen arranged for a sector of the Solid angle to decide whether this contains a vehicle-related object or not, and to determine the extent of this solid angle image area in a display image based on the result of the decision.

The image transformation unit can be set up to decide, based on the raw images of the camera, whether the sector of the solid angle contains a vehicle-related object

A distance sensor may be connected to the image transformation unit for measuring the distance to an object in the sector.

The monitored solid angle should be at least as large as that of a known exterior mirror or rearview mirror. In particular, the camera system forms a horizontal image angle of greater than 90 °.

The solid angle may include a direction opposite to the direction of travel. This achieves a detection of traffic coming from behind.

The solid angle may also include a direction orthogonal to the direction of travel. Thus, a detection of objects in the blind spot area is achieved.

The extent of the first image area corresponding to a first sector of the solid angle is preferably greater in the presence of a vehicle-related object in the first sector than in the absence of it. This makes it easier for the driver to recognize a vehicle-related object.

The extension of a second image area corresponding to a second sector of the solid angle adjacent to the first sector should be smaller in the presence of a vehicle-related object in the first sector than in the absence of a vehicle. By upsetting the second image area as it is, it is possible to avoid image areas that are far away from the first sector Sectors must be moved to accommodate the enlarged representation of the first sector. In particular, an image area which reproduces the traffic space behind the vehicle can thus remain unaffected by the detection of a vehicle-related object in a first sector located laterally of the vehicle.

Thus, objects in this second sector appear reduced in size when a vehicle-related object is detected in the first sector; however, they are not covered by the enlarged first sector.

Also, the position of a second image area corresponding to a second sector of the solid angle adjacent to the first sector on the display screen may depend on the presence of a vehicle-related object in the first sector. Thus, the compression of image areas, which is necessary to accommodate an enlarged representation of the first sector, inconspicuously distributed to several adjacent sectors.

In the absence of a vehicle-related object, the extent of the image area in the display image may depend on the relative position of the solid angle sector corresponding to the image area relative to the vehicle. A solid angle sector extending behind the vehicle should be made larger in the display image than a sector of equal extension extending laterally from the vehicle, since objects in the former may be significant to the driver even at a great distance.

The solid angle can be monitored by at least two cameras.

The object is further achieved by a method for assisting the driver of a vehicle, with the steps:
Capturing a raw image of a solid angle through a camera system;
Deciding whether a sector of the solid angle contains a vehicle-proximate object;
Transforming the raw image into a display image and outputting the display image to a display screen; wherein the transforming comprises determining the extent of an image area corresponding to the solid angle in the display image based on the result of the decision.

• – ein Computerprogrammprodukt, welches Instruktionen umfasst, die bei Ausführung auf einem Computer diesen befähigen, in einem Fahrerassistenzsystem wie oben beschrieben zu arbeiten oder das oben beschriebene Verfahren auszuführen,
• – ein computerlesbarer Datenträger, auf dem Programmanweisungen aufgezeichnet sind, die einen Computer befähigen, in der oben angegebenen Weise zu arbeiten, sowie
• – eine Vorrichtung zur Unterstützung des Fahrers eines Fahrzeugs mit Mitteln zum Erfassen eines Rohbildes eines Raumwinkels durch ein Kamerasystem; Mitteln zum Entscheiden, ob ein Sektor des Raumwinkels ein fahrzeugnahes Objekt enthält; Mitteln zum Transformieren des Rohbildes in ein Anzeigebild und Ausgeben des Anzeigebildes an einen Anzeigeschirm; wobei das Transformieren das Festlegen der Ausdehnung eines dem Raumwinkel entsprechenden Bildbereichs in dem Anzeigebild anhand des Ergebnisses der Entscheidung umfasst.

Further objects of the invention are:

• A computer program product comprising instructions which, when executed on a computer, enable it to operate in a driver assistance system as described above or to carry out the method described above,
• A computer-readable medium recorded with program instructions enabling a computer to operate in the manner indicated above; and
• A device for assisting the driver of a vehicle with means for acquiring a raw image of a solid angle through a camera system; Means for deciding whether a sector of the solid angle contains a vehicle-proximate object; Means for transforming the raw image into a display image and outputting the display image to a display screen; wherein the transforming comprises determining the extent of an image area corresponding to the solid angle in the display image based on the result of the decision.

Further features and advantages of the invention will become apparent from the following description of embodiments with reference to the accompanying figures. Show it:

1 a schematic view of a vehicle equipped with the driver assistance system motor vehicle;

2 the space angle monitored by the driver assistance system, a raw image derived therefrom and a display image in the absence of vehicle-related objects; and

3 the space angle monitored by the driver assistance system, a raw image derived therefrom, and a display image in the presence of a vehicle-related object.

1 shows in a schematic view from above a motor vehicle 1 with a camera system 2 comprising at least one digital video camera on the driver side of the vehicle for detecting raw images, an image transformation unit connected thereto 5 and a related display screen 3 for outputting display images.

One from the camera system 2 monitored solid angle 4 closes a direction opposite to the direction of travel 6 as well as an orthogonal direction 7 to both rear approaching vehicles and road users sideways from the vehicle 1 capture. It makes sense to use the solid angle 4 so chosen that he is also beyond these two directions 6 and 7 extends.

Around the solid angle 4 From a driver-familiar perspective, the camera may be mounted on the door conventionally occupied by an exterior mirror on a door of the vehicle; but it also comes, especially in the With regard to an unobstructed view to the rear, an attachment to a C-pillar or, in a combi vehicle, a D-pillar into consideration.

The camera system 2 may comprise a single camera with a lens, in particular a super wide-angle or fisheye lens whose field of view covers the entire solid angle 4 covers. The raw images provided by such a camera generally have strong perspective distortions that may make it difficult to recognize the displayed objects and the image transformation unit 5 at least partially corrected.

The camera system 2 but can also include two cameras, one of which is the one direction 6 enclosing angle range 9 and the other one the direction 7 enclosing angle range 10 surveyed, and where the union of both angular ranges 9 . 10 the solid angle 4 forms. In this case, the lens focal length is the angular range 9 surveillance camera significantly larger than that of the angle range 10 associated camera to capture the traffic behind the vehicle with high resolution and low distortion.

The two cameras should be placed close together to avoid parallax errors in combining the raw images of the two cameras into a single display image in the image transformation unit 5 to minimize.

Laterally on the vehicle 1 is - meaningfully in the immediate vicinity of the camera system 2 - a distance sensor 14 attached to the image transformation unit 5 connected is. It can be designed as a radar, infrared or optical sensor. Its detection range covers at least the side of the vehicle 1 lying angle range 10 from. In the simplest case, the distance sensor provides 14 only a scalar output representative of the distance to the nearest detected object; in that case it is the task of the image transformation unit 5 to determine the object and its position relative to the vehicle based solely on the information of the raw image. Preferably, the distance sensor provides 14 also an indication that describes the position of a detected object relative to the vehicle and from the image transformation unit 5 calculates the position of the image of this object in the raw image. The distance sensor 14 may be part of a known Totwinkelwarngeräts.

The lateral angle range 10 is significantly larger than the rear angle range 9 and therefore, if the camera system 2 includes a single camera in whose in 2 shown raw picture 11 a correspondingly larger area 10 ' , Rear approaching vehicles in the angle range 9 therefore appear in the raw picture 11 too small compared to a vehicle overtaking on a neighboring lane in the angular range 10 , To remedy this problem forms the image transformation unit 5 in a normal operating state, the behavior of a conventional outside mirror after, the a flat part for monitoring the rear angle range 9 and a cylindrically curved area for monitoring the lateral angle range 10 comprising: the image transformation unit 5 delivers to the display screen 3 a display image 12 with a partial surface 9 '' in which the rear angle range 9 can be seen in detail on a large scale, and a partial surface 10 '' in which the lateral angle range 10 is reproduced compressed at least in the horizontal direction. The compression can, as in 2 on the basis of a raw picture 11 and display image 12 drawn scale 13 clarified, at a sharp boundary between the faces 9 '' . 10 '' use abruptly; It is also conceivable a gradually occurring and with increasing distance from the partial surface 9 '' reinforcing compression.

This representation is appropriate as long as the angular range 10 contains no vehicle-related object that the driver should consider.

3 considers the case that the distance sensor 14 a vehicle-related object, z. A person 15 in a sector 16 the lateral angle range 10 detected. In 3 For reasons of simplicity, the sector is shown as representing the person 15 fully absorbs and essentially fills the sector; but the sector could also only take in part of the person or next to the person 15 contain even more environment. Would the raw picture 16 ' this sector 16 in the image transformation unit 5 just as compressed as that of a sector 17 without vehicle-related object, then the image of the person would be 15 in the display image 12 heavily distorted and the person difficult to recognize. That's why the image transformation unit gives 5 in the section 16 '' of the display image 12 the sector 16 undistorted or at most weakly compressed again, while for the rest of the angular range 10 the compression is adjusted so that the other sectors, such as the sector 17 , continue to find space in the display image.

The compression of the remaining sectors can be for the entire lateral angle range 10 be uniform; however, this has the consequence that when a vehicle-proximate object is detected, the entire scenery surrounding the vehicle shown in the remaining sectors must be shifted in the display image. To avoid this, the increased footprint of the section could be 16 '' be compensated by directly adjacent to him sections such as 17 '' be more compressed than more distant ones.

Also contemplated would be the compression of sectors that are free of near-vehicle objects when detecting an object in the sector 16 not to change and the sector 16 corresponding image section 16 '' the neighboring sector 17 in the display image.

It should be understood that the foregoing detailed description and drawings, while indicating certain exemplary embodiments of the invention, are intended for purposes of illustration only and are not to be construed as limiting the scope of the invention. Various modifications of the described embodiments are possible without departing from the scope of the following claims and their equivalence range. In particular, this description and the figures also show features of the embodiments which are not mentioned in the claims. Such features may also occur in combinations other than those specifically disclosed herein. Therefore, the fact that several such features are mentioned in the same sentence or in a different type of textual context does not justify the conclusion that they can occur only in the specific combination disclosed; instead, it is generally to be assumed that it is also possible to omit or modify individual ones of several such features, provided this does not call into question the functionality of the invention.

LIST OF REFERENCE NUMBERS

1

motor vehicle

2

video camera

3

display screen

4

solid angle

5

Image transformation unit

6

direction

7

direction

9

angle range

10

angle range

11

raw image

12

Sector of solid angle

14

distance sensor

16

Area of the raw picture

17

field

18

image area

19

image area

20

image area

21

image area

22

display image

23

Vehicle-related object

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 60029335 T2 [0005]

Claims (14)

Driver assistance system with a camera system ( 2 ), which has a solid angle ( 4 ) and at least one camera, a display screen ( 3 ), an image transformation unit ( 5 ) for transforming raw images of the camera system ( 2 ) in display images ( 12 ) and output the display images ( 12 ) to the display screen ( 3 ), which is set up for a sector ( 16 ) of the solid angle ( 4 ) to decide whether it is a vehicle-related object ( 15 ) or the extension of a sector ( 16 ) corresponding image area in a display image ( 12 ) on the basis of the result of the decision. Driver assistance system according to claim 1, wherein the image transformation unit ( 5 ), from the raw images of the camera system ( 2 ) to decide whether the sector ( 16 ) of the solid angle, a vehicle-related object ( 15 ) contains. Driver assistance system according to one of the preceding claims, in which a distance sensor ( 14 ) for measuring the distance to one in the sector ( 16 ) ( 15 ) with the image transformation unit ( 5 ) connected is. Driver assistance system according to one of the preceding claims, in which the camera system ( 2 ) images a horizontal image angle of greater than 90 °. Driver assistance system according to one of the preceding claims, in which the solid angle ( 4 ) a direction opposite to the direction of travel ( 6 ). Driver assistance system according to one of the preceding claims, in which the solid angle ( 4 ) a direction orthogonal to the direction of travel ( 7 ). Driver assistance system according to one of the preceding claims, in which the extent of the first sector ( 16 ) of the solid angle ( 4 ) in the presence of a vehicle-related object ( 15 ) in the first sector ( 16 ) is greater than in the absence. Driver assistance system according to claim 7, in which the extension of a second image area, one to the first sector ( 16 ) adjacent second sector ( 17 ) of the solid angle ( 4 ) is smaller in the presence of a vehicle-related object in the first sector than in the absence. Driver assistance system according to claim 7, in which the position of a second image area adjacent to the first sector ( 16 ) adjacent second sector ( 17 ) of the solid angle ( 4 ) corresponds, on the display screen, to the presence of a vehicle-related object ( 15 ) in the first sector ( 16 ) depends. Driver assistance system according to one of the preceding claims, in which the camera system ( 2 ) comprises at least two cameras. Driver assistance system according to claim 10, wherein the two cameras have different focal lengths. Method for assisting the driver of a vehicle, comprising the steps of: acquiring a raw image ( 11 ) of a solid angle ( 4 ) by a camera system; Decide if a sector ( 16 ) of the solid angle ( 4 ) a vehicle-related object ( 15 ) contains; Transform the raw image ( 11 ) into a display image ( 12 ) and outputting the display image ( 12 ) to a display screen ( 3 ); wherein the transforming is determining the extent of a sector ( 16 ) corresponding image area in the display image ( 12 ) based on the result of the decision. A computer program product comprising instructions which, when executed on a computer, enable it to operate as an image transformation unit in a driver assistance system according to any one of claims 1 to 11 or to carry out the method of claim 12. A computer-readable medium having program instructions recorded thereon enabling a computer to operate as an image transformation unit in a driver assistance system according to any one of claims 1 to 11 or to carry out the method of claim 12.

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