Reduced halo around light source

Abstract

A system includes a camera, an electronic control unit, and a visual display. The camera is operable to acquire acquired frames of an environment external to the system. The acquired frame has a plurality of pixels. An electronic control unit is coupled to the camera and is operable to detect one or more light sources in the acquired frame, determine a first number of a plurality of halo pixels around the one or more light sources among the plurality of pixels, and generating a processed frame by modifying the plurality of contrast curves of the plurality of pixels to reduce the plurality of halo pixels around the one or more light sources. A visual display is coupled to the electronic control unit and is operable to display the processed frame.

Description

Technical Field

[0001] This disclosure relates to a system and method for reducing halo around a light source. Background Technology

[0002] Being near car headlights, sunlight, and other bright objects can cause an adverse effect called "lightblooming" on a user's monitor. This adverse effect generally includes obstructing visual elements, reducing light pollution that hinders the user's view, blurring the landscape, and causing eye strain.

[0003] Therefore, those skilled in the art continue to conduct research and development efforts in the field of reducing halos seen around light sources acquired by cameras. Summary of the Invention

[0004] This document provides a system. The system includes a camera, an electronic control unit, and a vision display. The camera is operable to acquire frames of the environment outside the system. The acquired frames have multiple pixels. The electronic control unit is coupled to the camera and is operable to detect one or more light sources in the acquired frames, determine a first number of halo pixels around the one or more light sources among the multiple pixels, and generate a processed frame by modifying multiple contrast curves of the multiple pixels to reduce the number of halo pixels around the one or more light sources. The vision display is coupled to the electronic control unit and is operable to display the processed frame.

[0005] In one or more embodiments of the system, the camera is further operable to acquire multiple contrast curves in the acquired frames and to transmit the multiple contrast curves to an electronic control unit.

[0006] In one or more embodiments of the system, the camera is further operable to calculate a first number of multiple edges in the acquired frame and to transmit the first number of multiple edges to an electronic control unit.

[0007] In one or more embodiments of the system, the electronic control unit is further operable to modify multiple contrast curves in response to a first number of multiple edges exceeding an edge threshold.

[0008] In one or more embodiments of the system, the electronic control unit is further operable to calculate a second number of multiple edges in the processed frame.

[0009] In one or more embodiments of the system, the electronic control unit is further operable to further modify multiple contrast curves in response to a second number of multiple edges exceeding an edge threshold.

[0010] In one or more embodiments of the system, the electronic control unit is further operable to determine a second number of halo pixels in the processed frame.

[0011] In one or more embodiments of the system, the electronic control unit is further operable to further modify multiple contrast curves in response to a second number of multiple halo pixels exceeding a halo threshold.

[0012] In one or more embodiments, the system includes a transmitter coupled to an electronic control unit and operable to transmit processed frames to a back office located outside the system.

[0013] In one or more embodiments, the system includes sensing circuitry operable to consume processed frames.

[0014] This paper provides a method for reducing halos around light sources. The method includes acquiring frames of the environment outside a vehicle using a camera. The acquired frames have multiple pixels. The method includes detecting one or more light sources in the acquired frames using an electronic control unit, determining a first number of halo pixels around the one or more light sources among the multiple pixels using the electronic control unit, generating a processed frame by modifying multiple contrast curves of the multiple pixels to reduce the number of halo pixels around the one or more light sources using the electronic control unit, and displaying the processed frame on a visual display.

[0015] In one or more embodiments, the method includes acquiring multiple contrast curves in an acquired frame using a camera, and transferring the multiple contrast curves from the camera to an electronic control unit.

[0016] In one or more embodiments, the method includes using a camera to calculate a first number of multiple edges in an acquired frame, and transmitting the first number of multiple edges from the camera to an electronic control unit.

[0017] In one or more embodiments, the method includes modifying multiple contrast curves using an electronic control unit in response to a first number of multiple edges exceeding an edge threshold.

[0018] In one or more embodiments, the method includes using an electronic control unit to calculate a second number of multiple edges in a processed frame.

[0019] In one or more embodiments, the method includes further modifying multiple contrast curves using an electronic control unit in response to a second number of multiple edges exceeding an edge threshold.

[0020] In one or more embodiments, the method includes using an electronic control unit to determine a second number of a plurality of halo pixels in a processed frame.

[0021] In one or more embodiments, the method includes further modifying multiple contrast curves using an electronic control unit in response to a second number of multiple halo pixels exceeding a halo threshold.

[0022] In one or more embodiments, the method includes transmitting a processed frame from a transmitter to a back office, wherein the back office is located outside the vehicle.

[0023] This document provides a vehicle. The vehicle includes a camera, an electronic control unit, a vision display, and a transmitter. The camera is operable to acquire frames of the environment outside the vehicle. The acquired frames have multiple pixels. The electronic control unit is coupled to the camera and is operable to detect one or more light sources in the acquired frames, determine a first number of multiple halo pixels around the one or more light sources among the multiple pixels, and generate a processed frame by modifying multiple contrast curves of the multiple pixels to reduce the multiple halo pixels around the one or more light sources. The vision display is coupled to the electronic control unit and is operable to display the processed frame. The transmitter is coupled to the electronic control unit and is operable to transmit the processed frame to a back office located outside the vehicle.

[0024] The foregoing features and advantages of this disclosure, as well as other features and advantages, will become apparent from the following detailed description of the best mode for carrying out this disclosure when considered in conjunction with the drawings. Attached Figure Description

[0025] Figure 1 It is a schematic plan view of a vehicle according to one or more exemplary embodiments.

[0026] Figure 2 This is a flowchart of a technique for reducing halos around a light source, according to one or more exemplary embodiments.

[0027] Figure 3 This is a detailed flowchart of a technology according to one or more exemplary embodiments. Detailed Implementation

[0028] Embodiments of this disclosure provide a system and / or method for minimizing the circular starburst effect in radiometric measurements of camera images when viewing bright light. The technique detects each light source in the camera image and measures the radius from the center of the light source. After measurement, the image's contrast profile and / or edge count are modified to reduce halos while maintaining sharpness. This technique generally reduces the adverse effects of "halos" from the sun, external headlamps, and other bright objects. This technique provides enhanced visibility for the user by removing visually obstructive elements caused by halos.

[0029] refer to Figure 1 This diagram illustrates a schematic plan view of a vehicle 90 according to one or more exemplary embodiments. The vehicle 90 generally includes an electronic control unit 130, a communication bus 132, a camera 134, a vision display 136, a transmitter 138, a receiver 140, and sensing circuitry 142. The vehicle 90 may accommodate a driver 92. The camera 134 may receive light 94 from the exterior of the vehicle 90 and the surrounding environment 98. One or more of the light 94 may have sufficient intensity to cause a halo among the plurality of pixels 144 in the camera 134. The vehicle 90 may wirelessly communicate with a back office 96.

[0030] Electronic control unit 130 implements one or more processing circuits. Electronic control unit 130 is operable to receive acquired frames from camera 134, detect one or more bright lights (or light sources) 94 in the acquired frames, determine a first number of halo pixels 146 around one or more light sources 94 in pixels 144, and generate a processed frame 148 by modifying the contrast curve of pixels 144 to reduce the number of halo pixels 146 around one or more light sources 94. The processed frame 148 can be transmitted to visual display 136 for presentation to driver 92. The processed frame 148 can also be presented to sensing circuitry 142 for subsequent use. The processed frame 148 can also be transmitted via transmitter 138 to back office 96. Information 150 generated by back office 96 can be received by receiver 140.

[0031] In various embodiments, the electronic control unit 130 generally includes at least one microcontroller. The at least one microcontroller may include one or more processors, each of which may be embodied as a separate processor, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or a dedicated electronic control unit. The at least one microcontroller may be an electronic processor (implemented in hardware, software executing on hardware, or a combination of both). The at least one microcontroller may also include tangible, non-transitory memory (e.g., read-only memory in the form of optical, magnetic, and / or flash memory). For example, the at least one microcontroller may include a number of random access memories, read-only memories, flash memory, and other types of electrically erasable programmable read-only memories suitable for the application, as well as accompanying hardware in the form of high-speed clocks or timers, analog-to-digital and digital-to-analog circuitry, input / output circuitry and devices, and appropriate signal conditioning and buffering circuitry.

[0032] The computer-readable and executable instructions embodying this method can be recorded (or stored) in memory and executed as described herein. The executable instructions can be a set of instructions employed to run an application (in the foreground or background) on at least one microcontroller. The at least one microcontroller can receive commands and information in the form of one or more input signals from various controls or components and transmit instructions to other electronic components.

[0033] The communication bus 132 implements a multi-node, bidirectional digital bus. The communication bus 132 is operable to exchange data between the electronic control unit 130, camera 134, visual display 136, transmitter 138, receiver 140, and sensing circuit 142.

[0034] Camera 134 implements a forward-facing camera sensor. In various embodiments, camera 134 is precisely mounted at or near the front end of vehicle 90. In addition to the forward-facing camera 134, vehicle 90 may be equipped with other cameras, such as a left-side camera, a right-side camera, a rear camera, etc. Camera 134 and / or other cameras may be mounted at other locations on vehicle 90 to cover additional fields of view of environment 98. Camera 134 is operable to capture a sequence of images of environment 98 surrounding (e.g., in front of) vehicle 90. Camera 134 may be an optical camera operating in the visible and / or near-infrared spectrum. In some embodiments, camera 134 may include a high-speed shutter to limit blurring in the image due to movement of vehicle 90. In various embodiments, images may be reported on communication bus 132. In other embodiments, images may be transmitted to electronic control unit 130 and / or sensing circuitry 142 via a dedicated link.

[0035] The visual display 136 provides a two-dimensional display that is visible to the driver 92. The visual display 136 can be a cluster display located directly in front of the driver 92. The visual display 136 can also be a console display positioned for use by both the driver 92 and passengers.

[0036] Transmitter 138 is operable to transmit processed frame 148 to back office 96. Processed frame 148 is received at transmitter 138 via communication bus 132.

[0037] Receiver 140 is operable to receive information 150 from back office 96. Information 150 is transmitted to electronic control unit 130 and / or sensing circuit 142 via communication bus 132.

[0038] The sensing circuit 142 implements digital circuitry. The sensing circuit 142 is operable to perform a wide variety of operations on the acquired image and / or processed frame 148. For example, the sensing circuit 142 can mimic the function of the human visual system, enabling the machine to perceive and understand visual data. The sensing circuit 142 typically includes multiple interconnected components, such as sensors, filters, amplifiers, and processors. The sensing circuit 142 receives input from an image sensor that captures visual data and converts it into electrical signals. The electrical signals are then processed through various stages of the sensing circuit 142, including filtering to enhance specific features or remove noise, amplification to enhance the signal, and segmentation to identify different objects or regions within the image. The sensing circuit 142 also incorporates algorithms and computational models to analyze and interpret visual information. Analysis and interpretation can involve tasks such as object recognition, motion detection, depth perception, and scene understanding. The processed data is then used in various applications such as autonomous navigation, object tracking, surveillance systems, and image-based decision making. The sensing circuit 142 enables machines to perceive and understand visual information, bridging the gap between the physical world and digital systems, and providing a component in the development of computer vision and artificial intelligence systems. The sensing circuit 142 can also enable other use cases to meet specific application design guidelines.

[0039] In reference Figure 1 In case of reference Figure 2 The diagram illustrates a flowchart of an example technique for reducing halos around a light source according to one or more exemplary embodiments. Technique 160 (or method or process) can be performed by system 100 ( Figure 1 ) Implementation. As illustrated, technique 160 generally includes steps 162 to 184. The sequence of steps is shown as a representative example. Other step sequences can be implemented to meet the guidelines of a particular application.

[0040] In step 162, camera 134 can capture the acquired frame. The frame generally has a two-dimensional pixel matrix. The acquired frame is presented to steps 164, 168, and 172.

[0041] In step 164, one or more light sources 94 in the acquired frame may be detected by the electronic control unit 130. In step 166, the electronic control unit 130 may determine a first number of halo pixels 146 surrounding one or more light sources 94 among the pixels 144. The first number of halo pixels 146 is presented to step 174.

[0042] In step 168, camera 134 acquires the contrast curve of the acquired frame and transmits the contrast curve to electronic control unit 130. Electronic control unit 130 generates an intermediate processed frame by modifying the contrast curve received from camera 134. The modification of the contrast curve generally reduces the number of halo pixels 146 around one or more light sources 94. The number of halo pixels 146 retained in the intermediate processed frame is presented to step 174.

[0043] In step 172, camera 134 determines the sharpness of the acquired image by calculating a first number of edges in the acquired frame and then passing this edge number to electronic control unit 130. Electronic control unit 130 can determine whether the number of halo pixels 146 in the intermediate processed frame exceeds a halo threshold. If not, technique 160 returns to step 170 to further modify the contrast curve. If an acceptable number of halo pixels 146 remain in the intermediate processed frame, step 174 proceeds to step 176.

[0044] In step 176, the electronic control unit 130 calculates a second number of edges in the intermediate processed frame. If the number of edges in the intermediate processed frame exceeds an edge threshold, step 176 returns to step 170. Therefore, step 170 further modifies the contrast curve, checks the number of halo pixels 146 again in step 174, and step 160 returns to step 176. Once the number of edges in the intermediate processed frame is below the edge threshold, the intermediate processed frame is considered the final processed frame 178.

[0045] In step 180, the final processed frame 178 is presented to the visual display 136 and / or the sensing circuitry 142. In step 182, the final processed frame 178 is presented to the transmitter 138 for transmission to the back office 96. If the back office 96 has additional information for the vehicle 90, in step 184, the vehicle 90 can receive information 150 from the back office 96.

[0046] In reference Figure 1 and Figure 2 In case of reference Figure 3 This illustrates a detailed flowchart of technology 200 according to one or more exemplary embodiments. Technology 200 (or method or process) can be implemented by system 100 ( Figure 1 This is achieved by [method 1]. As illustrated, technique 200 generally includes steps 162 to 226. Steps 162 to 184 in technique 200 may be the same as those in technique 160. The sequence of steps is shown as a representative example. Other step sequences may be implemented to meet the criteria of a particular application.

[0047] In step 162, camera 134 can capture the acquired frame. In step 163, camera 134 can convert the acquired frame into monochrome. The monochrome frame is presented from step 163 to steps 164, 168, and 172.

[0048] As illustrated, step 164 generally includes steps 202 through 208. Step 202 reads the average brightness in the monochrome frame. Bit-plane slicing is performed in step 204. Gray-plane slicing is performed in step 206. In step 208, gray levels can be read from the slices. The resulting information is presented to step 166 to calculate the number of halo pixels 146.

[0049] Steps 168 and 170 are the same as in technique 160. The modified contrast curve is presented to step 174 to compare the number of halo pixels 146 with the halo threshold.

[0050] As illustrated, step 172 generally includes steps 210 through 226. In step 210, camera 134 locates edges in the monochrome frame. In step 212, holes and lines within the edges are identified. In step 214, the camera 134 fills in the holes within the lines.

[0051] In step 216, the centroid of the hole is located. In step 218, a pixel sample with a radius twice that of the hole is determined. In step 220, the brightness values ​​of the pixels in the sample region are read. In step 222, the brightness values ​​are stored as gradients. The gradients are presented to step 166 to calculate the number of halo pixels 146.

[0052] Steps 174 to 184 are the same as in technique 160. The final processed frame 178 can be transmitted to the back office 96, presented to the visual display 136 and / or presented to the sensing circuit 142.

[0053] In step 224, the camera locates edges within the sample region around the aperture. In step 226, the number of edges is determined. The number of edges is presented to step 176 for comparison with an edge threshold.

[0054] This system and / or method describes a technique that utilizes a camera by employing a real-time post-processing approach to reduce the circular starburst effect of bright light in the camera's field of view. This technique reduces the halo effect of light on the screen without degrading image quality and maintaining sharpness, aiming to provide the driver with an undisturbed environment. In practice, some direct benefits of reduced light pollution for users include, but are not limited to, less obstructed visibility, allowing users to focus on other nearby elements, the ability to enjoy a clearer and more comprehensive view, and the technology helping to reduce the risk of long-term eye strain.

[0055] Embodiments of this disclosure generally provide a system including a camera, an electronic control unit, and a visual display. The camera is operable to acquire frames of an environment external to the system. The acquired frames have a plurality of pixels. The electronic control unit is coupled to the camera. The electronic control unit is operable to detect one or more light sources in the acquired frames, determine a first number of a plurality of halo pixels around the one or more light sources among the plurality of pixels, and generate a processed frame by modifying a plurality of contrast curves of the plurality of pixels to reduce the plurality of halo pixels around the one or more light sources. The visual display is coupled to the electronic control unit. The visual display is operable to display the processed frame.

[0056] Numerical values ​​of parameters (e.g., quantities or conditions) in this specification, including the appended claims, should be understood to be modified in each instance by the term "about," regardless of whether "about" actually appears before the numerical value. "About" indicates that the numerical value allows for some slight imprecision (a certain approximation of the exact value; approximately or reasonably close to the value; nearly). If the imprecision provided by "about" cannot be understood in this ordinary sense in any other way in the art, then "about," as used herein, at least indicates the variation that may be produced by common methods of measuring and using such a parameter. Furthermore, the disclosure of ranges includes values ​​throughout the range and disclosures of further subdivided ranges. Each value within a range and the endpoints of the range are disclosed herein as separate embodiments.

[0057] While the best mode for carrying out this disclosure has been described in detail, those skilled in the art to which this disclosure pertains will recognize various alternative designs and embodiments for practicing this disclosure within the scope of the appended claims.

Claims

1. A system comprising: a camera operable to acquire an acquired frame of an environment external to the system, wherein the acquired frame has a plurality of pixels; an electronic control unit coupled to the camera and operable to: detect one or more light sources in the acquired frame; determine a first number of a plurality of halo pixels around the one or more light sources among the plurality of pixels; and generate a processed frame by modifying a plurality of contrast curves of the plurality of pixels to reduce the plurality of halo pixels around the one or more light sources; and a visual display coupled to the electronic control unit and operable to display the processed frame.

2. The system of claim 1, wherein the camera is further operable to: acquire the plurality of contrast curves in the acquired frame; and communicate the plurality of contrast curves to the electronic control unit.

3. The system of claim 1, wherein the camera is further operable to: calculate a first number of a plurality of edges in the acquired frame; and communicate the first number of the plurality of edges to the electronic control unit.

4. The system of claim 3, wherein the electronic control unit is further operable to: modify the plurality of contrast curves in response to the first number of the plurality of edges exceeding an edge threshold.

5. The system of claim 4, wherein the electronic control unit is further operable to: calculate a second number of the plurality of edges in the processed frame.

6. The system of claim 5, wherein the electronic control unit is further operable to: further modify the plurality of contrast curves in response to the second number of the plurality of edges exceeding the edge threshold.

7. The system of claim 1, wherein the electronic control unit is further operable to: determine a second number of the plurality of halo pixels in the processed frame.

8. The system of claim 7, wherein the electronic control unit is further operable to: further modify the plurality of contrast curves in response to the second number of the plurality of halo pixels exceeding a halo threshold.

9. The system of claim 1, further comprising: a transmitter coupled to the electronic control unit and operable to transmit the processed frame to a back office, wherein the back office is external to the system.

10. A method for reduced halo around light sources, comprising: acquiring, with a camera, an acquired frame of an environment external to a vehicle, wherein the acquired frame has a plurality of pixels; detecting, with an electronic control unit, one or more light sources in the acquired frame; determining, with the electronic control unit, a first number of a plurality of halo pixels around the one or more light sources among the plurality of pixels; generating a processed frame by modifying, with the electronic control unit, a plurality of contrast curves of the plurality of pixels to reduce the plurality of halo pixels around the one or more light sources; and displaying the processed frame on a visual display. ​

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