Method and system for varying an image processing frequency of an HD headlight

Abstract

Method for varying an image processing frequency (4, 6) of an HD headlight, wherein a respective output video signal (2) provided by a headlight control is reproduced by the HD headlight, wherein a respective input video signal (1) is provided to the headlight control in time with an input image frequency, wherein the respective output video signal (2) is calculated by the headlight control in time with the image processing frequency (4, 6) according to at least one image processing function, wherein the headlight control is subjected to a respective computing time expenditure resulting from the at least one image processing function, wherein the image processing frequency (4, 6) predetermines an available computing time between two consecutive or two definably spaced respective output video signals (2), wherein the image processing frequency (4,6) is varied depending on a respective driving situation, and wherein a respective computing capacity is allocated to a computing unit of the headlight control depending on the image processing frequency (4, 6).

Description

[0001] The present invention relates to a method for varying the image processing frequency of an HD headlight, in which a headlight control system takes a current driving situation into account. Furthermore, a system is claimed that enables implementation of the method.

[0002] High-resolution, or "HD" for short, headlights on a vehicle create light patterns in the area in front of the vehicle, representing, for example, a low beam or a high beam. An HD headlight with a multitude of light point sources, such as LEDs, arranged on a matrix display is also referred to as an HD matrix headlight. The image of each light point source of the HD matrix headlight in the area in front of the vehicle corresponds to a pixel in the light pattern.

[0003] Due to the high resolution of the light image, an oncoming vehicle can be masked out in the driver's own high beam, for example, by influencing individual LEDs, without sacrificing illumination of the remaining area. Furthermore, the HD matrix headlights, equipped with a suitable headlight control system, can also be used to display additional information. For example, information related to driver support and vehicle control can be projected as symbols in the area in front of the vehicle.

[0004] Depending on the requirements, e.g. due to the driver's own driving speed, a multitude of computing tasks arise for the headlight control in order to provide the HD matrix headlights with a video signal for illuminating the area in front of the vehicle within a specified refresh rate.

[0005] Document DE 10 2018 123 407 A1 discloses a headlight of a motor vehicle comprising an LED matrix with light-emitting diodes as light sources and an LCD screen with liquid crystal segments as shading elements for shading light from the LED matrix. The surroundings are captured by a camera, which has a refresh rate of approximately 60 Hz.

[0006] EP 2 591 952 B1 describes a headlight system for a motor vehicle. The headlight system is controlled by an engine control unit, together with the ignition system and the fuel system of the motor vehicle.

[0007] In a vehicle environment to be illuminated, the document DE 10 2012 220 089 A1 distinguishes between making a road path visible to a driver and making an area outside the vehicle visible for image capture by an image capture device. For this purpose, a control unit has operating cycles with different cycle times assigned to the two tasks.

[0008] Against this background, it is an object of the present invention to provide a method for relieving the load on a headlight control system of HD headlights, which method influences a video signal provided by the headlight control system depending on the traffic situation. This should free up computing capacity in the headlight control system for additional functions. Furthermore, a system should be provided that enables implementation of the method.

[0009] To achieve the aforementioned object, a method for varying an image processing frequency of an HD headlight is proposed, wherein the HD headlight reproduces a respective output video signal provided by a headlight controller. A respective input video signal is provided to the headlight controller at the rate of an input image frequency. The headlight controller calculates the respective output video signal according to at least one image processing function at the rate of the image processing frequency. The headlight controller is subjected to a respective computing time expenditure resulting from the at least one image processing function, wherein the image processing frequency specifies an available computing time between two successive respective output video signals. The image processing frequency is varied depending on a respective driving situation.

[0010] The input image frequency is, for example, 60 Hz, meaning that a new image is provided to the headlight control system as an input video signal every 16.6 milliseconds. The input video signal comes, for example, from a camera in front of the vehicle, which, in a continued version, records the area in front of the vehicle to be illuminated, including, for example, oncoming traffic that cannot be illuminated by the HD headlight, and forwards it to the headlight control system. At least one image processing function then calculates a light image of the HD headlight or the HD matrix headlight, in which, for example, corresponding projection areas of the light image are shaded in the case of oncoming traffic that cannot be illuminated.

[0011] In one embodiment of the method according to the invention, the at least one image processing function is, for example, the low beam, high beam, cornering light, masking out oncoming traffic, masking out road users ahead, masking out pedestrians, brightening up dark objects in the area in front of the vehicle or the display of symbols.

[0012] Depending on the selection of one or more image processing functions of the at least one image processing function, computationally intensive image processing processes occur. In total, this can result in a longer computing time in the computing unit of the headlight control than the calculation time available due to the image processing frequency and / or the available computing capacity. Functional restrictions are the result. Depending on a driving situation or a traffic situation, the method according to the invention advantageously makes it possible to vary the image processing frequency so that the available calculation time is sufficient to calculate all selected image processing functions for the output signal. This is the case, for example, with a stationary vehicle, since there are no dynamic changes in the input signal.In the case of a stationary vehicle in front of the driver's own (stationary) vehicle, whose silhouette should be shadowed by the driver's high beam, for example, there is no need to constantly recalculate a shadowing area. A high image processing frequency, such as the input frame rate, is then unnecessary.

[0013] In a further embodiment of the method according to the invention, the image processing frequency is set to the input image frequency. At the same time, a driving situation with a driving speed above 3 km / h exists.

[0014] In another embodiment of the method according to the invention, the image processing frequency is reduced to half the input image frequency. At the same time, a driving situation with a driving speed below 3 km / h exists.

[0015] The method according to the invention thus advantageously enables an image processing frequency that is adaptively adapted to the respective driving situation or traffic situation, ie in a changing traffic situation the image processing frequency is higher than in a calm traffic situation.

[0016] In a further embodiment of the method according to the invention, the image processing frequency is reduced if a respective input video signal does not change compared to at least one immediately preceding input video signal, and the image processing frequency is increased if a respective input video signal changes compared to at least one immediately preceding input video signal. For example, a predetermined number of immediately consecutive input video signals are monitored to determine whether a change occurs.

[0017] According to the invention, a respective computing capacity is allocated to a computing unit of the headlight control depending on the image processing frequency. It is conceivable that this allocation is carried out dynamically. This means that, for example, when the vehicle is stationary (scenario: vehicle is stationary, camera in front of the vehicle detects a red traffic light), the computing capacity available on the computing unit of the headlight control for calculating the light image of the output video signal is reduced and increased again when the vehicle continues to drive. This advantageously increases the computing capacity for other functions during such a stationary phase. This is particularly advantageous if the computing unit of the headlight control has been virtually assigned to a processor unit that also processes tasks other than headlight control, or which is accessed by multiple control units and whose computing resources are distributed as required.

[0018] Furthermore, a system for varying an image processing frequency of an HD headlight is claimed, wherein the system has an HD headlight, a headlight controller with a computing unit, and a camera in front of the vehicle. The HD headlight is designed to reproduce a respective output video signal provided by a headlight controller. The camera in front of the vehicle is configured to provide a respective input video signal to the headlight controller in time with an input image frequency. The headlight controller is configured to calculate the respective output video signal according to at least one image processing function in time with the image processing frequency, wherein the headlight controller is subjected to a respective computing time expenditure resulting from the at least one image processing function.The image processing frequency determines the available processing time between two consecutive output video signals. Furthermore, the headlight control is configured to vary the image processing frequency depending on the driving situation.

[0019] In a further embodiment of the system according to the invention, the image processing frequency corresponds to the input image frequency, while at the same time the driving speed is above 3 km / h or there is at least one object moving in front of the vehicle.

[0020] In another embodiment of the system according to the invention, the image processing frequency is reduced to half the input image frequency and at the same time the driving speed is below 3 km / h.

[0021] In yet another embodiment of the system according to the invention, the image processing frequency is reduced compared to the input image frequency if a respective input video signal does not change compared to at least one immediately preceding input video signal. Otherwise, the image processing frequency corresponds to the input image frequency if a respective input video signal changes compared to at least one immediately preceding input video signal.

[0022] According to the invention, a respective computing capacity is allocated to a computing unit of the headlight control depending on the image processing frequency.

[0023] Furthermore, a computer program product comprising a computer-readable medium is claimed, on which program code executable on a processing unit of a headlight control system of an HD headlight is stored. When executed on the processing unit, the program code causes the processing unit to perform at least one of the following steps in a continuous iterative execution: • Receiving a respective input video signal from a vehicle in-field camera at the rate of an input frame rate, • Calculation of a respective output video signal according to at least one image processing function in time with an image processing frequency, • Providing the respective output video signal to the HD spotlight, • Variation of the image processing frequency depending on the respective driving situation.

[0024] Further advantages and embodiments of the invention will become apparent from the description and the accompanying drawings.

[0025] It is understood that the above-mentioned features can be used not only in the combination specified in each case, but also in other combinations or on their own, without departing from the scope of the present invention.

[0026] Fig. 1 shows a time sequence diagram of video signals present in a headlight control in an embodiment of the method according to the invention.

[0027] In Fig.1 shows a time sequence diagram 10 of video signals 3 present in a headlight control in one embodiment of the method according to the invention. An input video signal 1 provided with an input image frequency is processed by the headlight control in time with a respective image processing frequency 4, 6 to form an output video signal 2. Along a time arrow 9, a vehicle is initially at full speed with a constantly changing traffic situation, so that the image processing frequency 4 corresponds to the input image frequency of the input video signal 1, e.g. 60 Hz. With each new video signal 3, image changes occur which must be detected by the headlight control and can lead to changes in the output video signal 2. If the traffic situation or driving situation changes, e.g.If the vehicle comes to a standstill and, as a result, no or only minor changes (compared to the preceding video signal 3) occur in the input video signal 1, a switching condition 5 is reached, after which the image processing frequency 6 is reduced to half the original image processing frequency 4, for example to 30 Hz. This means that the HD matrix headlight is only provided with a changed output video signal by the headlight control every 33.3 milliseconds, which advantageously also reduces the computing effort and frees up computing capacity for other functions.

Claims

[1] Method for varying an image processing frequency (4, 6) of an HD headlight, wherein a respective output video signal (2) provided by a headlight control is reproduced by the HD headlight, wherein a respective input video signal (1) is provided to the headlight control in time with an input image frequency, wherein the respective output video signal (2) is calculated by the headlight control in time with the image processing frequency (4, 6) according to at least one image processing function, wherein the headlight control is subjected to a respective computing time expenditure resulting from the at least one image processing function, wherein an available computing time between two consecutive or two definably spaced respective output video signals (2) is predetermined by the image processing frequency (4,6) is varied depending on a respective driving situation, and wherein a respective computing capacity is allocated to a computing unit of the headlight control depending on the image processing frequency (4, 6). [2] Method according to claim 1, wherein the at least one image processing function can be selected from a plurality of image processing functions, such as dipped beam, high beam, cornering light, masking out oncoming traffic, masking out road users ahead, masking out pedestrians, brightening up dark objects in the area in front of the vehicle, displaying symbols or others. [3] Method according to one of the preceding claims, in which the image processing frequency (4) is set to the input image frequency and a driving situation with a driving speed above a definable value exists. [4] Method according to one of claims 1 or 2, in which the image processing frequency (6) is reduced to half the input image frequency and the driving speed is below a definable value. [5] Method according to one of claims 1 or 2, wherein the image processing frequency (4, 6) is reduced if a respective input video signal (1) does not change compared to at least one immediately preceding input video signal (1), and wherein the image processing frequency (4, 6) is increased if a respective input video signal changes compared to at least one immediately preceding input video signal (1). [6] System for varying an image processing frequency (4, 6) of an HD headlight, the system comprising an HD headlight, a headlight control with a computing unit, and a camera in front of the vehicle, the HD headlight being designed to reproduce a respective output video signal (2) provided by a headlight control, the camera in front of the vehicle being configured to provide a respective input video signal (1) to the headlight control in time with an input image frequency, the headlight control being configured to calculate the respective output video signal (2) according to at least one image processing function in time with the image processing frequency (4, 6), the headlight control being subjected to a respective computing time expenditure resulting from the at least one image processing function, the image processing frequency (4,6) an available calculation time between two successive respective output video signals (2) is predetermined, wherein the headlight control is configured to vary the image processing frequency (4, 6) depending on a respective driving situation, and wherein a respective computing capacity is allocated to a computing unit of the headlight control depending on the image processing frequency (4, 6). [7] System according to claim 6, wherein the at least one image processing function can be selected from a plurality of possible image processing functions such as dipped beam, high beam, cornering light, masking out oncoming traffic, masking out road users ahead, masking out pedestrians, brightening up dark objects in the area in front of the vehicle, and displaying symbols. [8] System according to one of claims 6 or 7, in which the image processing frequency (6) is reduced compared to the input image frequency if a respective input video signal (1) does not change compared to at least one immediately preceding input video signal (1), and in which the image processing frequency (4) corresponds to the input image frequency if a respective input video signal changes compared to at least one immediately preceding input video signal (1). [9] A computer program product comprising a computer-readable medium on which a program code executable on a processing unit of a headlight control system of an HD headlight is stored, wherein the program code, when executed on the processing unit, causes the processing unit to perform, in a continuous iterative execution, at least one of the following steps: • Receiving a respective input video signal (1) from a vehicle in-field camera at the rate of an input image frequency, • Calculation of a respective output video signal (2) according to at least one image processing function in time with an image processing frequency (4, 6), • Provision of the respective output video signal (2) to the HD spotlight, • Variation of the image processing frequency (4, 6) depending on the respective driving situation • Allocation of a respective computing capacity on a computing unit of the headlight control depending on the image processing frequency (4, 6).

Images