Using NIR illuminators to improve vehicle camera performance in low-light scenarios

Abstract

Vehicle, comprising: a rear view camera; a lighting system for illuminating the field of view of the rear view camera; a near-infrared (NIR) illumination device integrated into the lighting system; and a tax system for: Pulsing the NIR illuminator on and off based on a frame rate of the rear view camera; and Process images captured by the camera while the NIR illuminator is on separately from images captured while the NIR illuminator is off.

Description

TECHNICAL FIELD

[0001] The present disclosure relates generally to illumination for vehicle cameras, and more particularly to the use of near-infrared (NIR) illuminators to improve vehicle camera performance in low-light scenarios. GENERAL STATE OF THE ART

[0002] Modern vehicles may include one or more cameras that display images through a vehicle display. Such a camera may be a rear-facing camera or a rearview camera, which allows the vehicle display to show an area behind the vehicle when the vehicle is in reverse.

[0003] Vehicles may also include lighting systems, such as headlights, fog lights, backup lights, etc., that serve to illuminate the area around the vehicle. The one or more cameras may require light to function properly and may therefore be dependent on the vehicle's lighting systems.

[0004] US Pat. No. 7,568,823 B2 discloses a vehicle with a rearview camera whose field of view can be illuminated by a lighting system. The lighting system comprises LEDs that are pulsed at a frequency that is invisible to the human eye. SUMMARY

[0005] The appended claims define this application. The present disclosure summarizes aspects of the embodiments and should not be construed as limiting the claims. Other implementations are contemplated in accordance with the techniques described herein, as will become apparent to one of ordinary skill in the art upon review of the following drawings and detailed description, and these implementations are intended to be within the scope of this application. Example embodiments are shown utilizing NIR illuminators in conjunction with vehicle cameras. A disclosed example vehicle includes a lighting system, a rearview camera, and a near-infrared (NIR) illuminator integrated with the lighting system.The vehicle control system also includes a control system for pulsing the NIR illuminator on and off based on a frame rate of the rearview camera and for processing images captured by the camera while the NIR illuminator is on separately from images captured while the NIR illuminator is off.

[0006] A disclosed exemplary method includes illuminating a field of view of a vehicle rearview camera with an illumination system. The method also includes pulsing a near-infrared (NIR) illuminator on and off based on a frame rate of the rearview camera, wherein the NIR illuminator is integrated into the illumination system. The method further includes processing images captured by the camera while the NIR illuminator is on separately from images captured while the NIR illuminator is off. The method further includes displaying the processed images on a vehicle display.

[0007] Another example may include means for illuminating a field of view of a vehicle rearview camera, means for pulsing a near-infrared (NIR) illuminator on and off based on a frame rate of the rearview camera, means for processing images captured by the camera while the NIR illuminator is on separately from images captured while the NIR illuminator is off, and means for displaying the processed images on a vehicle display. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] For a better understanding of the invention, reference may be made to embodiments shown in the following drawings. The components in the drawings are not necessarily to scale, and related elements may be omitted or, in some cases, enlarged in proportion to emphasize and clearly illustrate the novel features described herein. Furthermore, system components may be arranged in various ways, as is known in the art. Furthermore, in the drawings, corresponding parts are designated by like reference numerals throughout the different views. Fig. 1 illustrates an exemplary rear perspective view of a vehicle according to embodiments of the present disclosure. Fig. 2 illustrates an exemplary block diagram of electronic components of the vehicle from Fig. 1. Fig. 3 illustrates an exemplary tail lamp of a vehicle according to embodiments of the present disclosure. Fig. 4 illustrates a flowchart of an example method according to embodiments of the present disclosure. DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0009] While the invention may be embodied in various forms, some exemplary and non-limiting embodiments are shown in the drawings and described below. It is to be understood that the present disclosure is intended to illustrate the invention by way of example and is not intended to limit the invention to the specific embodiments shown. As noted above, vehicles may include one or more cameras that can provide images of the vehicle's surroundings. These cameras may be positioned to capture a full 360-degree view.

[0010] In low-light scenarios, these cameras may lack light, limiting their ability to capture and process images. For example, low-light scenarios can occur at night, when a vehicle enters a tunnel, or at any other time when the camera cannot capture sufficient light.

[0011] Generally, a camera can produce a better image by capturing more light, as long as the image isn't washed out or overexposed. Therefore, some vehicles may increase the amount of light emitted by one or more of the vehicle's lighting systems (headlights, fog lights, taillights, etc.). However, many jurisdictions impose vehicle regulations that limit the amount of visible light that can be emitted. This may be for safety reasons, so that light from one vehicle cannot blind the driver of another.

[0012] To provide a clearer, sharper, and / or wider-area image, example vehicles of the present disclosure may include one or more NIR illuminators. The NIR illuminators may provide the camera with additional incident light without causing problems for a driver of another vehicle. The additional light may enable a computing system to distinguish features or objects in the image with greater skill than in images where NIR illuminators are not used. Furthermore, the NIR illuminators may allow the image to be wider-area, such that features and objects may be detected over a much larger area than when the NIR illuminators are not used.

[0013] However, images with NIR illumination can cause a discrepancy or problem with the color consistency of the images. Many camera sensors can misinterpret the NIR light as red, green, or blue light, causing errors in the image. To combat this problem, embodiments of the present disclosure can pulse the NIR illuminator such that some images are captured when the NIR illuminator is on and some images are captured when the NIR illuminator is off. As a result, systems and devices of the present disclosure can incorporate increased camera sensitivity and range without sacrificing color consistency.

[0014] In some examples, a vehicle may include a camera, a lighting system, and an NIR illuminator. The NIR illuminator may be integrated with the lighting system. In this way, both the lighting system and the NIR illuminator may provide light to the camera's field of view. The vehicle may also include a control system configured to pulse the NIR illuminator on and off based on a camera frame rate. For example, the camera frame rate may be 30 frames per second. The camera may capture light for 1 / 30 of a second and add the incoming light over that period to determine the image. This process may be performed 30 times per second.In some examples, the NIR illuminator may be pulsed on and off at a rate of 15 times per second, such that the NIR illuminator is on for image 1, off for image 2, and so on. The resulting individual images may be processed and displayed to a user such that the camera images include increased visibility and increased range while maintaining color consistency.

[0015] Fig. 1 illustrates an exemplary vehicle 100 according to embodiments of the present disclosure. The vehicle 100 may be a standard gasoline-powered vehicle, a hybrid vehicle, an electric vehicle, a fuel cell vehicle, or any other type of vehicle with any other type of propulsion. The vehicle 100 may be non-autonomous, semi-autonomous, or autonomous. The vehicle 100 includes parts related to propulsion, such as a drivetrain including an engine, a transmission, a suspension, a driveshaft, and / or wheels, etc. In the illustrated example, the vehicle 100 may include one or more electronic components (discussed below with respect to Fig. 2).

[0016] The representation in Fig. 1, the vehicle 100 may include a lighting system 102, a near-infrared (NIR) illuminator 104, an on-board computing platform 106, an ambient light sensor 108, and a rearview camera 110.

[0017] The lighting system 102 may include one or more lights or light-emitting devices configured to illuminate a field of view of the vehicle's driver, one or more vehicle cameras, and / or one or more vehicle sensors. For example, the lighting system 102 may include one or more headlights, auxiliary lights, turn signals, tail lights, brake lights, the center high mount stop lamp (CHMSL), and the license plate lamp. Furthermore, the lighting system 102 may include one or more incandescent bulbs, light emitting diodes (LEDs), high intensity discharge (HID) lamps, fluorescent lamps, or other light sources. In some examples, the lighting system 102 may be a light dedicated to the camera 110. The vehicle 100 may also include a near-infrared illuminator 104.In some examples, the NIR illumination device 104 may include a plurality of NIR LEDs or another NIR light source. The NIR LEDs may be arranged among the LEDs of the illumination system. This is illustrated in FIG. Fig. 3 shown in more detail.

[0018] The NIR illumination device 104 can be configured to emit light at a specific wavelength or wavelength range. For example, infrared light has a wavelength of approximately 700 nm and higher. NIR light can therefore include light from approximately 700 nm up to 3000 nm or higher.

[0019] However, some NIR illuminators may have an upper limit of 750 nm and may be configured to emit light below 750 nm. NIR illuminators may also be configured to emit light at higher or lower wavelengths and / or to emit light that is invisible to the human eye.

[0020] The NIR illuminator 104 may be controlled by one or more other vehicle systems, such as the on-board computing platform 106. In some examples, the NIR illuminator 104 may be controlled to pulse on and off at a particular frequency or with a particular pattern.

[0021] The vehicle 100 may also include a camera 110. The camera 110 may be a rearview camera, a forward-facing camera, a side-facing camera, or any other vehicle camera. The camera 110 may be configured to capture images displayed on a display of the vehicle 100, which may include a center console display, a dashboard display, a display on a rearview mirror of the vehicle, a handheld device display, or another display.

[0022] The camera 110 may operate at a specific frame rate. As noted above, a camera frame rate may be 30 frames per second. This may mean that the camera collects light for 1 / 30 of a second, adds the incoming light over that period, or otherwise processes it to determine the image, with this process being performed 30 times per second.

[0023] In some examples, the camera 110 may collect light for less than 1 / 30 of a second for each image (i.e., less than the time period available for the given image). For example, if the camera is operating in a brightly lit environment, the camera may operate at 30 frames per second, but capturing each image may involve collecting light for less than the time period available for the image (e.g., 1 / 60 of a second instead of 1 / 30 of a second). The exact amount of time for collection may depend on the amount of light entering the camera, such that a single image may be determined based on the incident light. If a large amount of incident light is present, the camera may collect light for less than the time period available for each image to avoid washing out and overexposure of the image.

[0024] In low-light scenarios, the camera can collect light for the entire period available for each image. However, in many cases, even this amount of time may not be enough to produce a usable single image. Instead, the single image may be too dark and lack sufficient contrast to detect objects and features.

[0025] In some examples, camera 110 may operate at a specific gain, which may be used to adjust the image. The gain value may change based on the amount of light collected for a given image. For example, if a small amount of light was collected by the camera, the gain may be increased. This increase in gain may increase the signal coming from the camera, but it may also increase the noise level. Therefore, increasing the gain requires considering a trade-off between increasing the signal and keeping the noise level low.

[0026] The camera 110 may also include one or more filters. In some examples, the camera 110 may limit the wavelength of the incoming light with a cutoff filter. For example, the filter may limit light with a wavelength greater than 750 nm from reaching the camera sensor. In practice, an IR cutoff filter may be a bandpass filter that limits light within a specific wavelength band.

[0027] The vehicle 100 may also include an onboard computing platform 106, which may also be referred to as a control system or computing system. The onboard computing system 106 may include one or more processors, memory, and other components configured to perform one or more functions, acts, steps, blocks, or methods described herein. The onboard computing system 106 may be separate from or integrated with the systems of the vehicle 100.

[0028] In some examples, the on-board computing system 106 may be configured to control the camera 110, the lighting system 102, and / or the NIR illuminator 104. The on-board computing system 106 may pulse the NIR illuminator 104 on and off based on the camera's frame rate. As mentioned above, the camera may operate at a particular frame rate, which may indicate how many images per second are captured by the camera. The on-board computing system 106 may pulse the NIR illuminator 104 at a particular pulse rate based on the camera's frame rate, such as 100%, 50%, or another pulse rate. Furthermore, the on-board computing system 106 may pulse the NIR illuminator 104 on and off with a particular duty cycle (ie, a 50% duty cycle in which the NIR illuminator is on for 50% of the time and off for 50% of the time).Therefore, for each image captured by camera 110, NIR illuminator 104 may (i) be on or off, and (ii) if on, it may only be on for a portion of the time interval during which the camera collects incident light for the image.

[0029] In some examples, such as in low-light conditions, the NIR illuminator 104 may be pulsed for the entire time interval used to collect light for a given image. This may allow for greater light capture by the camera 110, such that resulting images may have greater sharpness and objects or features within the frame may be more easily detected.

[0030] In some examples, the on-board computing system 106 may pulse the NIR illuminator on and off at a rate 50% less than the camera's frame rate. In this example, half of the images captured by the camera may include exposure to NIR light and half may not. The on-board computing system 106 may also pulse the NIR illuminator 104 on for a first period of time and then off for a second period of time, where the first period corresponds to a period for which the rearview camera collects a signal for each image. This may be a duty cycle for the NIR illuminator 104, which may depend on one or more characteristics of the camera 110.

[0031] In some examples, embodiments of the present disclosure may include determining that the vehicle 100 and / or the camera 110 is operating in a low-light condition. One or more sensors, computing devices, and / or algorithms may be used to determine this. For example, the ambient light sensor 108 may detect a level of ambient light. If the amount of detected light is below a threshold amount, this may indicate that the vehicle is operating in a low-light condition.

[0032] In some examples, determining the low-light condition may include determining the low-light condition based on a gain applied to a signal from the camera. For example, the camera 110 and / or the on-board computing system 106 may apply a greater gain to images captured by the camera 110 when the amount of incident light is low. Thus, when the camera or processor applies a greater amount of gain (i.e., above a threshold amount), this may indicate that the camera 110 is operating in a low-light condition.

[0033] In some examples, the amount of time the camera collects incident light can be used to determine that the camera is in a low-light condition. For example, the camera may have a frame rate that determines a time interval over which the camera collects light for each frame. If the camera collects light for the entire interval, this may indicate that the camera is not receiving a large amount of incident light and may be operating in a low-light condition.

[0034] In response to any determination that the camera and / or the vehicle is / are in a low light condition, the on-board computing system 106 may responsively turn on the NIR illuminator 104.

[0035] The on-board computing system 106 may also be configured to process images captured by the camera while the NIR illuminator is on separately from images captured while the NIR illuminator is off. Separate processing may include applying one or more separate filters, algorithms, and / or image processing techniques to each set of images. Furthermore, the on-board computing system 106 may process the two sets of images partially separately, may combine the two sets of images, or may perform processing of the two sets of images together. Furthermore, separate processing of images may include partially or completely separate processing over time, processing groups of images together. Other processing techniques may also be used.

[0036] When two sets of images are captured and processed (those with NIR turned on and those with NIR turned off), this allows one set to be used for a first purpose while the other can be used for a second purpose. For example, images captured with NIR turned off can be used to determine color data and maintain color consistency. These images are captured in such a way that the NIR light does not affect the camera, and the true red, green, and blue values can be more easily detected. On the other hand, the set of images captured with the NIR illuminator turned on can provide additional contrast, sharpness, and object detection capability. The additional NIR light in these images can allow for less intensive image processing, can provide a user with a larger field of view, and can provide other benefits.

[0037] Fig. Figure 2 illustrates an example block diagram 200 showing the electronic components of the vehicle 100 according to some embodiments. In the illustrated example, the electronic components 200 include the control system 106, the infotainment head unit 220, the communication module 230, sensors 240, the electronic control unit 250, and the vehicle data bus 260.

[0038] The control system 106 may include a microcontroller unit, controller, or processor 210 and a memory 212. The processor 210 may be any suitable processing device or set of processing devices, such as, but not limited to, a microprocessor, a microcontroller-based platform, an integrated circuit, one or more field-programmable gate arrays (FPGAs), and / or one or more application-specific integrated circuits (ASICs). The memory 212 may be volatile memory (e.g., RAM, including non-volatile RAM, magnetic RAM, ferroelectric RAM, etc.), non-volatile memory (e.g., disk storage, FLASH memory, EPROMs, EEPROMs, memristor-based non-volatile solid-state memory, etc.), non-modifiable memory (e.g., EPROMs), read-only memory, and / or high-capacity storage devices (e.g.,Hard disks, solid-state drives, etc.). In some examples, memory 212 includes multiple types of memory, including volatile memory and non-volatile memory.

[0039] Memory 212 may be computer-readable media on which one or more sets of instructions, such as software for carrying out the methods of the present disclosure, may be embedded. The instructions may embody one or more of the methods or logic described herein. For example, during execution of the instructions, the instructions are located wholly or at least partially in any one or more of memory 212, the computer-readable medium, and / or the processor 210.

[0040] The terms "non-transitory computer-readable medium" and "computer-readable medium" include a single medium or multiple media, such as a centralized or distributed database and / or associated caches and servers, on which one or more sets of instructions are stored. Further, the terms "non-transitory computer-readable medium" and "computer-readable medium" include any physical medium capable of storing, encoding, or carrying a set of instructions for execution by a processor or for causing a system to perform any one or more of the methods or acts disclosed herein. As used herein, the term "computer-readable medium" is expressly defined to include any type of computer-readable storage device and / or storage disk and excludes propagation of signals.

[0041] The infotainment main unit 220 may provide an interface between the vehicle 100 and a user. The infotainment main unit 220 may include one or more input / output devices, such as the display 222 and the user interface 224, to receive input from the user(s) and display information. The input devices may include, for example, a control knob, a dashboard, a digital camera for image capture and / or visual command recognition (such as the camera 110 in Fig. 1), a touchscreen, an audio input device (e.g., a cabin microphone), buttons, or a touchpad. The output devices may include instrument cluster outputs (e.g., dials, lighting devices), actuators, a front display, a center console display (e.g., a liquid crystal display (LCD), an organic light emitting diode (OLED) display, a flat panel display, a solid-state display, etc.), and / or speakers. In the illustrated example, the infotainment head unit 220 includes hardware (e.g., a processor or controller, memory, data storage, etc.) and software (e.g., an operating system, etc.) for an infotainment system (such as Ford®'s SYNC® and MyFord Touch®, Toyota®'s Entune®, GMC®'s IntelliLink®, etc.). In some examples, the infotainment head unit 220 may share a processor with control system 106.Furthermore, the infotainment main unit 220 displays the infotainment system, for example, on a center console display of the vehicle 100.

[0042] The communication module 230 may include wired or wireless network interfaces to enable communication with external networks. The communication module 230 may also include hardware (e.g., processors, memory, storage, etc.) and software to control the wired or wireless network interfaces. In the illustrated example, the communication module 230 may include a Bluetooth module, a GPS receiver, a dedicated short range communication (DSRC) module, a WLAN module, and / or a cellular modem, all electrically coupled to one or more corresponding antennas.

[0043] For example, the cellular modem may include controllers for standards-based networks (e.g., Global System for Mobile Communications (GSM), Universal Mobile Telecommunications System (UMTS), Long Term Evolution (LTE), Code Division Multiple Access (CDMA), WiMAX (IEEE 802.16m), and Wireless Gigabit (IEEE 802.11ad), etc.). The WLAN module may include one or more controllers for wireless local area networks, such as a Wi-Fi® controller (including IEEE 802.11 a / b / g / n / ac or others), a Bluetooth® controller (based on the Bluetooth® Core Specification maintained by the Bluetooth Special Interest Group), and / or a ZigBee® controller (IEEE 802.15.4), and / or a Near Field Communication (NFC) controller, etc.Furthermore, the internal and / or external network(s) may be public networks, such as the Internet; a private network, such as an intranet; or combinations thereof, and may use a variety of network protocols currently available or later developed, including, but not limited to, TCP / IP-based network protocols.

[0044] The communication module 230 may also include a wired or wireless interface to enable direct communication with an electronic device (such as a smartphone, tablet, laptop, etc.). An exemplary DSRC module may include radio(s) and software to transmit messages and establish direct connections between the vehicles. DSRC is a wireless communication protocol or system primarily intended for the transportation sector and operates in the 5.9 GHz frequency range.

[0045] Sensors 240 may be arranged in any suitable manner in and around vehicle 100. In the illustrated example, sensors 240 include an ambient light sensor 242 and a vehicle gear sensor 244. Ambient light sensor 242 may measure an amount of ambient light. One or more cameras or other systems of the vehicle may require a threshold amount of light to operate and / or trigger an action based on the amount of light detected by ambient light sensor 242. Vehicle gear sensor 244 may indicate what gear the vehicle is in (e.g., reverse, neutral, etc.). One or more actions may be performed by various systems and devices of vehicle 100 based on a particular gear.The various sensors of the vehicle 100 may be analog, digital, or any other type and may be coupled to one or more other systems and devices described herein.

[0046] One or more of the sensors 240 may be positioned in or on the vehicle. For example, the ambient light sensor 242 may be positioned on or near a window of the vehicle such that the sensor 242 is not obscured and can measure an amount of ambient light.

[0047] The ECUs 250 may monitor and control subsystems of the vehicle 100. The ECUs 250 may communicate and exchange information via the vehicle data bus 260. Furthermore, the ECUs 250 may communicate properties (such as the status of the ECU 250, sensor readings, control status, error and diagnostic codes, etc.) to and / or receive requests from other ECUs 250. Some vehicles 100 may have seventy or more ECUs 250 located at various locations around the vehicle 100 and communicatively coupled by the vehicle data bus 260. The ECUs 250 may be discrete sets of electronic components that include their own circuitry(s) (such as integrated circuits, microprocessors, memory, data storage, etc.) and firmware, sensors, actuators, and / or mounting elements.In the illustrated example, the ECU 250 may include the telematics control unit 252, a body control unit 254, and a speed control unit 256.

[0048] The telematics control unit 252 may control the monitoring of the vehicle 100, for example, using data received from a GPS receiver, the communications module 230, and / or one or more sensors. The body control unit 254 controls various subsystems of the vehicle 100. For example, the body control unit 254 may control power windows, a central locking system, a power sunroof control, an engine immobilizer, and / or power mirrors, etc. The speed control unit 256 may receive one or more signals via a data bus 260 and, in response, may control a speed, acceleration, or other aspect of the vehicle 100.

[0049] The vehicle data bus 260 may include one or more data buses that communicatively couple the control system 106, the infotainment head unit 220, the communication module 230, the sensors 240, the ECU 250, and other devices or systems connected to the vehicle data bus 260. In some examples, the vehicle data bus 260 may be implemented in accordance with the Controller Area Network (CAN) bus protocol as defined by International Standards Organization (ISO) 11898-1. Alternatively, in some examples, the vehicle data bus 250 may be a Media-Oriented Systems Transport (MOST) bus or a CAN Flexible Data (CAN-FD) bus (ISO 11898-7).

[0050] Fig. 3 illustrates an exemplary tail lamp 300 according to embodiments of the present disclosure. The tail lamp 300 may be an exemplary arrangement and should not be construed as limiting the scope of the present disclosure. The tail lamp 300 may include a housing 302, a plurality of lighting system LEDs 304, a plurality of NIR LEDs 306, and one or more other lighting elements 308.

[0051] The representation in Fig. According to Figure 3, the NIR LEDs 306 may be integrated with the lighting system LEDs 304 in an "every-other" arrangement. Some examples may include other arrangements and may include more or fewer LEDs. Furthermore, some example lighting systems may not include any lighting system LEDs at all and may only include NIR LEDs integrated into the standard vehicle lighting system.

[0052] In some examples, the NIR LEDs 306 may be oriented to point or face in the same direction as the LED 304 of the illumination system. Alternatively, one or more NIR LEDs 306 may point in a different direction, such that the NIR LEDs provide a larger or smaller field of illumination. Furthermore, one or more NIR LEDs 306 may be configured to change their orientation via one or more actuators, such that they can be dynamically aligned by one or more systems or devices. Other variations are also possible.

[0053] Fig. 4 illustrates a flowchart of an exemplary method 400 according to embodiments of the present disclosure. The method 400 may enable a vehicle camera (and a user) to view images with a larger range and higher clarity in low-light scenarios. The flowchart of Fig. 4 is representative of machine-readable instructions stored in a memory (such as memory 212) and may include one or more programs that, when executed by a processor (such as processor 210), may cause vehicle 100 and / or one or more systems or devices to perform one or more of the functions described herein. While the exemplary program with reference to the Fig. 4, many other methods may alternatively be used to perform the functions described herein. For example, the execution order of the blocks may be rearranged or performed sequentially or in parallel, and blocks may be altered, removed, and / or combined to perform method 400. Since method 400 may be used in conjunction with the components of Fig.1-3, some functions of these components are not described in detail below.

[0054] Method 400 may begin at block 402. At block 404, the system may be activated. This may include powering on, initializing, or otherwise preparing one or more systems or devices for operation.

[0055] At block 406, method 400 may include detecting a low-light condition based on an ambient sensor. As described above, an ambient sensor may detect when a light level is below a threshold. The threshold may be a set value, may be dynamic, may be predetermined, or may be selected based on one or more sensors or systems of the vehicle. For example, the threshold may be set based on the quality of images produced under certain lighting conditions to avoid situations where image quality degrades too much.

[0056] If no low-light condition is detected by the ambient light sensor, block 408 may include detecting a low-light condition based on a gain applied to a signal from the camera. As discussed above, the camera gain may be high under certain lighting conditions, and a high gain may indicate that the camera is operating in a low-light condition. It should be noted that blocks 406 and 408 are described as being performed sequentially; however, they may be performed in parallel, in reverse order, and each block may not be performed at all. Further, additional blocks (not shown) may be included in which alternative techniques for detecting a low-light condition are used.

[0057] If a low-light condition has been detected based on either the ambient light sensor or the gain, block 410 may include illuminating the camera's field of view with the vehicle lighting system. This may include turning on the headlights, taillights, or other vehicle lights.

[0058] At block 412, method 400 may include determining a camera frame rate. As discussed above, the camera frame rate may indicate how many images per second can be captured by the camera, which corresponds to the period of time the camera collects light for each image.

[0059] At block 414, the method 400 may include pulsing the NIR illuminator at a pulse rate based on the camera frame rate. For example, the pulse rate may be 50% of the camera frame rate, meaning that the NIR illuminator is on for half of the images captured by the camera and off for half. The method 400 may also include synchronizing the camera with the NIR illuminator such that the NIR illuminator turn-on pulse begins at the same time as, or nearly at the same time as, the start of an image capture period.

[0060] The camera may then capture images for a given period of time, during which some images include NIR illumination and some images do not. At block 416, method 400 may include processing images captured with the NIR illuminator turned on. This may include using one or more filters, algorithms, processes, or other image processing techniques to obtain one or more processed images. These processed images may be brighter, may enable feature or object detection, or may otherwise provide different options than images captured without the NIR illuminator turned on.

[0061] At block 418, method 400 may include processing images captured with the NIR illuminator turned off. Processing these images may be similar or identical to processing images captured with the NIR illuminator turned on. In some examples, block 418 may include applying a color correction process to the images to maintain color consistency. Other image processing techniques may also be used.

[0062] At block 420, method 400 may include displaying the processed images. This may include combining the "NIR-on" images with the "NIR-off" images to obtain an overall image in which color consistency is maintained and a larger range and better object detection are obtained. Therefore, the displayed images may achieve the best result, in which range and detection are improved without sacrificing color consistency. The processed images may be displayed on any display of the vehicle, including a center console, a front display, a dashboard, a rearview mirror display, or a portable display coupled to the vehicle.

[0063] Method 400 may then continue pulsing the NIR illuminator, capturing images, processing the images, and displaying the images until the low-light condition is no longer detected or another action is performed (such as turning off the camera). At block 422, method 400 may then end.

[0064] In this application, the use of disjunction is intended to include conjunction.

[0065] The use of definite or indefinite articles is not intended to indicate cardinality. In particular, a reference to "the" object or "an" object is also intended to refer to one of a possible plurality of such objects. Furthermore, the conjunction "or" can be used to indicate features that are present simultaneously, rather than mutually exclusive alternatives. In other words, the conjunction "or" should be understood to imply "and / or." The terms "includes," "containing," and "comprise" are inclusive and have the same scope as "comprises," "comprising," and "include," respectively.

[0066] The embodiments described above, and in particular any "preferred" embodiments, are possible exemplary implementations and are presented merely for a clear understanding of the principles of the invention. Many variations and modifications may be made to the embodiment(s) described above without substantially departing from the spirit and principles of the techniques described herein. All modifications are intended to be included within the scope of this disclosure and protected by the following claims.

Claims

[1] Vehicle comprising: a rear view camera; a lighting system for illuminating the field of view of the rear view camera; a near-infrared (NIR) illumination device integrated into the lighting system; and a tax system for: Pulsing the NIR illuminator on and off based on a frame rate of the rear view camera; and Process images captured by the camera while the NIR illuminator is on separately from images captured while the NIR illuminator is off. [2] The vehicle of claim 1, wherein the lighting system comprises a set of LED lights and wherein the NIR illuminator comprises a set of NIR LEDs mounted between the set of LED lights of the lighting system. [3] The vehicle of claim 1, wherein the NIR illuminator is configured to emit light below 750 nm. [4] The vehicle of claim 1, wherein the control system further serves to: Determining that the rear view camera is in a low light condition; and Turning on the NIR illumination device in response. [5] The vehicle of claim 4, wherein determining that the rearview camera is in a low-light condition is based on a gain applied to an image captured by the camera. [6] The vehicle of claim 1, wherein pulsing the NIR illuminator on and off based on a frame rate of the rearview camera comprises pulsing the NIR illuminator at half the rate of the rearview camera such that half of the images captured by the rearview camera are exposed to the NIR light and half of the images are not. [7] The vehicle of claim 1, wherein pulsing the NIR illuminator comprises repeatedly turning the illuminator on for a first period of time and then turning it off for a second period of time, the first period of time corresponding to a period of time for which the rear view camera collects a signal for each image. [8] The vehicle of claim 1, further comprising a cut-off filter for attenuating light emitted by the NIR illuminator to between 700 and 750 nm. [9] Method comprising: Illuminating a field of view of a vehicle rear view camera with a lighting system; Pulsing a near-infrared (NIR) illuminator on and off based on a frame rate of the rear view camera, wherein the NIR illuminator is integrated into the lighting system; Processing images captured by the camera while the NIR illuminator is on separately from images captured while the NIR illuminator is off; and Displaying the processed images on a vehicle display. [10] The method of claim 9, wherein the illumination system comprises a set of LED lights and wherein the NIR illumination device comprises a set of NIR LEDs mounted between the LED lights of the illumination system. [11] The method of claim 9, further comprising: Determining that the rear view camera is in a low light condition; and Turning on the NIR illumination device in response. [12] The method of claim 11, wherein determining that the rearview camera is in a low-light condition is based on a gain applied to an image captured by the camera. [13] The method of claim 9, wherein pulsing the NIR illuminator on and off based on a frame rate of the rearview camera comprises pulsing the NIR illuminator at half the rate of the rearview camera such that half of the images captured by the rearview camera are exposed to the NIR light and half of the images are not. [14] The method of claim 9, wherein pulsing the NIR illuminator comprises repeatedly turning the illuminator on for a first period of time and then turning it off for a second period of time, the first period of time corresponding to a period for which the rear view camera collects a signal for each image. [15] The method of claim 9, further comprising determining color data based on the images taken while the NIR illuminator is off.

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