Driver assistance camera arrangement

Abstract

The invention relates to an automotive driver assistance camera arrangement (20) with an electronic camera control (30), a light intensity image sensor array (26) with multiple sensor pixels (S26), and a color filter array (28) optically assigned to the light intensity image sensor array (26) and electronically controllable, whose filter pixels (F28) can be adjusted pixel by pixel by the camera control (30) with respect to their transmission spectrum between at least two different colors (R, G, B, Y, C), wherein the camera control (30) has a color pattern memory (36) in which at least two different filter color patterns (RGGB, RCCC, RYYB) are stored, wherein a vehicle sensor (34) is provided which is informationally assigned to the camera control (30), and wherein the camera control (30) selects the filter color pattern (RGGB, RCCC, RYYB) generated by the color filter array (28) depending on the signal (B) of the vehicle sensor (34).

Description

[0001] The invention relates to an automotive driver assistance camera arrangement which is used, for example, in a motor vehicle for image-based recording and evaluation of the driving situation.

[0002] For camera arrangements in various application areas (e.g., driver assistance systems or highly automated driving), electronic cameras equipped with a light intensity image sensor array with a large number of sensor pixels are used. Since a sensor pixel provides a summary brightness value for a wide range of the detected light spectrum, a corresponding static color filter array is placed in front of the image sensor array in order to generate color-differentiated images. The static color pattern of the color filter array is selected depending on the task of the respective driver assistance camera arrangement, so that multiple cameras may be required for different tasks and, in particular, for different lighting conditions.

[0003] CN 1 300 504 A discloses an image processing device with extraction means for extracting pixels located near selected pixels. Furthermore, a categorization device is provided for categorizing the pixels. US 2019 / 0 346 599 A1 discloses another image processing device.

[0004] The object of the invention is to create a simple driver assistance camera arrangement that is suitable for various tasks.

[0005] This object is achieved according to the invention with an automotive driver assistance camera arrangement having the features of claim 1.

[0006] The automotive driver assistance camera arrangement according to the invention has an electronic camera control that controls the remaining components of the camera arrangement. The camera arrangement has a light intensity image sensor array with a plurality of sensor pixels, each of which is light-sensitive to a wide range of the visible spectrum or, if appropriate, also the invisible spectrum of light. For chromatic differentiation, an electronically controllable color filter array is provided, which is optically and physically assigned to the light intensity image sensor array. Particularly preferably, each sensor pixel of the image sensor array is assigned a filter pixel of the color filter array. Each individual filter pixel of the controllable color filter array can be set by the camera control with respect to the respective transmission spectrum between at least two colors, for example, red, green, blue, yellow, cyan, and / or colorless.

[0007] The camera control system has a color pattern memory in which at least two different filter color patterns are stored. The stored color patterns are particularly preferably exclusively so-called Bayer color patterns, which typically feature a non-proportional distribution of the two to three transmission spectra or colors across all filter pixels.

[0008] The camera control is further informationally assigned to a vehicle sensor, wherein the camera control selects the filter color pattern generated by the color filter array depending on the signal of the vehicle sensor.

[0009] The vehicle sensor can, for example, be an ambient brightness sensor, aligned in the direction of travel or the forward viewing direction. However, the ambient brightness sensor does not necessarily have to be a separate sensor. The ambient brightness sensor can also be formed by the image sensor array itself. The image sensor array or a module evaluating the image signals can, for example, output a dark signal if the image sensor array detects only weak brightness signals over a large area, for example, when a color filter array that allows the entire light spectrum to pass through is switched off.

[0010] The electronically controllable color filter array allows the filter color pattern to be adapted to the situation. In conventional driver assistance applications, this can reduce the number of driver assistance camera arrays or significantly improve the detection performance of a single driver assistance camera array.

[0011] Particularly preferably, a Bayer color pattern with the color pattern red-green-green-blue is stored in the color pattern memory, which can be referred to as the standard Bayer color pattern.

[0012] An embodiment of the invention is explained in more detail below with reference to the figures. They show: Fig. 1 schematically shows a motor vehicle with an automotive driver assistance camera arrangement with a light intensity image sensor array and a color filter array in front of it, and Fig. 2 a - c three different filter color patterns stored in a color pattern memory of the driver assistance camera arrangement of the Fig. 1 and filtered by the color filter array of the Fig. 1 can be represented.

[0013] In the Fig. 1 schematically shows a motor vehicle 10 with an automotive driver assistance camera arrangement 20. The motor vehicle 10 has a vehicle-mounted body 12, a vehicle-mounted windshield 14, and a vehicle-mounted sensor 34, which in this case is an ambient brightness sensor directed forward in the direction of travel x. Furthermore, the motor vehicle 10 has a driver assistance controller 40, which evaluates the image signals coming from the driver assistance camera arrangement 20 and, if necessary, generates driver assistance signals.

[0014] The driver assistance camera arrangement 20 has a vehicle-mounted driver assistance camera 22, which is arranged behind the windshield 14 and oriented in the direction of travel x, and has an electronic camera control 30 which controls the driver assistance camera 22 and which converts the signals received by the driver assistance camera 22 into image signals so that they can be interpreted by the driver assistance control 40.

[0015] The electronic driver assistance camera 22 has a camera lens 24, a controllable color filter array 28 and immediately behind it a light intensity image sensor array 26, as in the Fig. 2. The image sensor array 26 has a plurality of light-sensitive sensor pixels S26 that are light-sensitive to a wide range of visible light.

[0016] The color filter array 28 has, for example, a plurality of identical filter pixels F28 that can be electrically controlled pixel by pixel, each of which can be alternately adjusted between five transmission spectra, in this case between the colors red R, green G, blue B, yellow Y, and colorless C, i.e., unfiltered. The color filter array 28 consists of a special glass with electrochromatic properties. The transmission spectrum of a filter pixel F28 is adjusted by a corresponding electrical voltage applied to the respective filter pixel F28.

[0017] The camera control 30 has a color pattern memory 36 in which three different filter color patterns RGGB, RYYB, RCCC are stored, which are in the Fig. 2 a to c, which are all three so-called Bayer color samples. The first in the Fig. The filter color pattern RGGB shown in Figure 2a is the classic Bayer color pattern, in which the sum of the color pixels F28 of the color red R and the color blue B corresponds to the sum of the color pixels F28 of the color green G. The second and third filter color patterns RYYB, RCCC each have a surplus of filter pixels F28 in yellow Y and in colorless C, respectively.

[0018] In principle, further filter color patterns can also be stored in the color pattern memory 36.

[0019] Furthermore, the camera control 30 has a color filter array control 32, which electronically controls the color filter array 28 such that it generates a filter color pattern as stored in the color pattern memory 36. The camera control 30 selects the filter color pattern depending on the signal B of the vehicle sensor 34. In good brightness, for example, the Fig. 2a is chosen, in very dark conditions, for example, the standard Bayer colour pattern RGGB shown in Fig. The filter color pattern RCCC shown in Figure 2c was selected.

[0020] The images provided in this way by the driver assistance camera arrangement 20 are interpreted by the driver assistance control 40, which, if necessary, outputs corresponding assistance signals to other vehicle units.

Claims

[1] Automotive driver assistance camera arrangement (20) with an electronic camera control (30), a light intensity image sensor array (26) having a plurality of sensor pixels (S26), and a color filter array (28) optically associated with the light intensity image sensor array (26) and electronically controllable, the filter pixels (F28) of which can be adjusted pixel by pixel by the camera control (30) with regard to their transmission spectrum between at least two different colors (R, G, B, Y, C), wherein the camera control (30) has a color pattern memory (36) in which at least two different filter color patterns (RGGB, RCCC, RYYB) are stored, wherein a vehicle sensor (34) is provided which is informationally associated with the camera control (30), and wherein the camera control (30) selects the filter color pattern (RGGB, RCCC, RYYB) generated by the color filter array (28) depending on the signal (B) of the vehicle sensor (34). [2] The automotive driver assistance camera assembly (20) according to claim 1, wherein the filter color patterns (RGGB, RCCC, RYYB) stored in the color pattern memory (36) are Bayer color patterns. [3] The automotive driver assistance camera assembly (20) of claim 2, wherein a color pattern (RGGB) stored in the color pattern memory (36) is a red-green-green-blue Bayer color pattern. [4] Automotive driver assistance camera arrangement (20) according to one of the preceding claims, wherein the vehicle sensor (34) is an ambient brightness sensor.

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