Display control method, device, projection device, and computer-readable storage medium

Abstract

The present disclosure provides a display control method, device, projection device, and computer-readable storage medium, which belong to the field of assisted driving technology. The method includes: when it is detected that the image elements displayed in the display area have changed, controlling the electrical parameters of the backlight corresponding to the target image partition in the display area, so that the brightness difference between the first image partition included in the target image partition and the second image partition is less than a set difference threshold, wherein the first image partition is a partition in the display area where the image element changes, and the second image partition is a partition in the display area where there are image elements and no image element changes. The method can make the brightness of the image partitions with image elements in the display area uniform.

Description

Technical Field

[0001] The present disclosure relates to the field of assisted driving technology, and in particular to a display control method, device, projection device, and computer-readable storage medium. Background Art

[0002] Head Up Display (HUD) is a device that projects key information directly onto the windshield or a transparent display in front of the driver's line of sight, allowing the driver to obtain important information such as vehicle speed, navigation, traffic sign recognition, incoming call information, etc. in real time without looking down at the dashboard or navigation system. With the development of technology, HUD has more functions and is smarter, such as Augmented Reality Head Up Display (AR-HUD), which combines virtual information with the actual road environment through augmented reality technology to provide more intuitive navigation guidance.

[0003] Due to the complexity of the HUD optical system, brightness may be lost in various components during the projection process, resulting in differences in brightness in different partitions of the entire display area. Especially when the brightness differences among partitions are large, the image displayed in the darker partition cannot be seen clearly, and the brighter partition may produce glare, resulting in a poor user experience. Summary of the invention

[0004] The present disclosure provides a display control method, device, projection device, and computer-readable storage medium. The method can make the brightness of image partitions having image elements in a display area uniform.

[0005] The technical solution of the present disclosure is achieved as follows:

[0006] In a first aspect, the present disclosure provides a display control method, the method comprising: when a change in an image element displayed in a display area is detected, controlling the electrical parameters of a backlight corresponding to a target image partition in the display area so that a brightness difference between a first image partition included in the target image partition and a second image partition is less than a set difference threshold, wherein the first image partition is a partition in the display area where an image element change occurs, and the second image partition is a partition in the display area where there is an image element and no image element change occurs.

[0007] In a second aspect, the present disclosure provides a display control device, comprising: a control part, configured to control the electrical parameters of a backlight corresponding to a target image partition in the display area when a change in an image element displayed in the display area is detected, so that the brightness difference between a first image partition included in the target image partition and a second image partition is less than a set difference threshold, wherein the first image partition is a partition in the display area where an image element change occurs, and the second image partition is a partition in the display area where there is an image element and no image element change occurs.

[0008] In a third aspect, the present disclosure provides a projection device, which includes: a display control unit and a display unit; the display control unit is configured to control the electrical parameters of the backlight corresponding to the target image partition in the display area when a change in the image elements displayed in the display area is detected, so that the brightness difference between the first image partition included in the target image partition and the second image partition is less than a set difference threshold, wherein the first image partition is a partition in the display area where the image element change occurs, and the second image partition is a partition in the display area where the image element exists and no image element change occurs; the display unit is configured to enable a visual confirmer to visually confirm the image by projecting the image onto the projected component.

[0009] In a fourth aspect, an embodiment of the present disclosure provides a display control device, comprising: a processor and a memory; the processor is used to execute instructions stored in the memory to implement the display control method described in the first aspect.

[0010] In a fifth aspect, the present disclosure provides a computer-readable storage medium storing at least one instruction, wherein the at least one instruction is used to be executed by a processor to implement the display control method as described in the first aspect.

[0011] In a sixth aspect, the present disclosure provides a vehicle, comprising the head-up display device described in the fifth aspect.

[0012] The present disclosure provides a display control method, which includes: in the case of detecting that the image elements displayed in the display area have changed, controlling the electrical parameters of the backlight corresponding to the target image partition in the display area, so that the brightness difference between the first image partition included in the target image partition and the second image partition is less than a set difference threshold, wherein the first image partition is a partition in the display area where the image elements have changed, and the second image partition is a partition in the display area where there are image elements and no image elements have changed. In this way, when there is a change in the image elements projected to the display area, the brightness of the image partitions in the display area is adjusted, so that the brightness difference between the partition to which the changed image elements belong and the image partition to which the image elements have not changed is less than the difference threshold, that is, the brightness of each image partition is uniform, thereby ensuring that the image elements can be displayed clearly and improving the driving experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 A schematic diagram of the structure of the projection device provided by the present disclosure.

[0014] Figure 2 A schematic diagram of partitions on a backlight panel corresponding to the backlight provided in the present disclosure.

[0015] Figure 3 A schematic diagram of the composition of a vehicle-mounted system provided by the present invention.

[0016] Figure 4 An exemplary top view of a vehicle provided by the present disclosure.

[0017] Figure 5 An exemplary perspective view from the driver's seat of a vehicle is provided for the present disclosure.

[0018] Figure 6 This is one of the flow charts of a display control method provided by the present disclosure.

[0019] Figure 7a This is one of the schematic diagrams of image elements in the display area provided by the present disclosure.

[0020] Figure 7b The second schematic diagram of the image elements in the display area provided by the present invention.

[0021] Figure 7c This is the third schematic diagram of the image elements in the display area provided by the present invention.

[0022] Figure 7d This is the fourth schematic diagram of the image elements in the display area provided by the present invention.

[0023] Figure 8 This is one of the schematic diagrams of image partitioning provided by the present disclosure.

[0024] Fig. 9 The second schematic diagram of image partitioning provided by the present invention.

[0025] Fig.10 The third schematic diagram of image partitioning provided by the present invention.

[0026] Fig.11 The second flowchart of a display control method provided by the present invention.

[0027] Fig.12 The fourth schematic diagram of image partitioning provided by the present invention.

[0028] Fig.13 This is the fifth schematic diagram of image partitioning provided by the present invention.

[0029] Fig.14 The third flowchart of a display control method provided by the present invention.

[0030] Fig.15 A schematic diagram of the composition of a display control device provided by the present invention.

[0031] Fig.16 The present invention provides a schematic structural diagram of a projection device.

[0032] Fig.17 A structural block diagram of a brightness adjustment system provided by the present invention. DETAILED DESCRIPTION

[0033] The technical solutions in the present disclosure will be described clearly and completely below in conjunction with the accompanying drawings in the present disclosure.

[0034] It should be understood that in the solution provided in the present application, the display control method can be executed by a projection device or some components in the projection device, wherein the projection device has a projection function, for example, an AR-HUD, a HUD or other devices with a projection function. Some components in the projection device can be a processing chip, a processing circuit, a processor, etc.

[0035] See also Figure 1 In the exemplary implementation architecture of the projection device 170 shown, the display control unit 150 generates a signal 412 based on the input data 420. The display unit 160 may include: an optical path component 161, a display panel 503, a backlight plate 502, and a filter 162. The optical path component 161 reflects the projection image 212 from the display control unit 150 multiple times and displays it on the projected component 204.

[0036] The optical path component 161 can reflect the projected image 212 onto the projected component 204 through the hole 216. The viewer can view the projected image 212 in the display area where the projected image 212 is projected onto the projected component 204. In some examples, the optical path component 161 may include one or more reflectors (plane mirrors) and concave mirrors (magnifying glasses). The projected image 212 is reflected back by the reflector and magnified by the concave mirror and then reflected to the projected component 204 to form a virtual image 40 that can be observed by the user. The visual effect presented by the virtual image 40 is that the virtual image 40 is projected onto the projection surface 41 at a set distance in front of the projected component 204, but the real environment remains visible through the projection surface 41. In some examples, the optical path component 161 can also be omitted, and the projected image 212 can be directly projected onto the projected component 204 to form a virtual image 40 on the projection surface 41.

[0037] The display unit 160 may include: a display panel 503, which is used to generate images based on different types of display technologies, such as thin film transistor liquid crystal display, digital light processing using micromirror arrays, organic light emitting diodes, laser scanning technology, etc. A backlight panel 502, which is used to provide a uniform light source to ensure that the image on the display panel can be clearly displayed. The light source in the backlight panel may be an LED, a halogen lamp, a laser, etc. The backlight panel includes a plurality of backlights, each of which serves as a light source for an area in the display panel. The display unit 160 may also include: a filter 162, which is used to provide color for the monochromatic light source. Figure 2 As shown, a backlight panel 502 exemplarily includes 20 backlight lamps 501 , each backlight lamp 501 corresponds to a display partition 504 of a display panel 503 , that is, each backlight lamp 501 is used to provide light source for a display partition 504 of the display panel 503 . Figure 2 The sizes of the backlight plate 501 and the display panel 503 are only exemplary, and in practice, the sizes of the two can be the same or different. In addition, the layout of the backlight is only an example, and the sizes of the display partitions corresponding to each backlight can be the same or different.

[0038] The display control unit 150 is a core component of the projection device, and is used to generate and project a display image 212 .

[0039] The projection device 170 of the present embodiment can be mounted on a vehicle for use, and the vehicle is equipped with the vehicle-mounted system 100 .

[0040] See also Figure 3, which shows an example of a vehicle-mounted system 100 that can be applied to the technical solution of the present disclosure. In some examples, the vehicle equipped with the system 100 can be an internal combustion engine vehicle using an engine as a power source, a hybrid vehicle using an engine and an electric motor as a power source, an electric vehicle using an electric motor as a power source, and other types of vehicles. In the subsequent content of this specification, the vehicle equipped with the vehicle-mounted system 100 is referred to as the present vehicle.

[0041] like Figure 3 As shown, the vehicle-mounted system 100 includes: a navigation subsystem 110, an environment detection device group 120 for obtaining the vehicle's environment during the vehicle's driving, a vehicle driving state detection device group 130, a data processing unit 140, a display control unit 150, and a display unit 160. The above components or device groups are coupled together through a communication bus 12. In some examples, the communication bus 12 is used for connection and communication between the above components or device groups. It should be noted that Figure 3 Only a portion of the in-vehicle system 100 is shown, not all of the components of the in-vehicle system 100 .

[0042] exist Figure 3 In the navigation subsystem 110, a positioning device 111 and a map information storage device 112 are included. The positioning device 111 can locate the position of the vehicle based on the global positioning system (GPS), China's Beidou system, Russia's GLONASS system, Europe's Galileo system, Japan's Quasi-Zenith Satellite System (QZSS), India's Indian Regional Navigation Satellite System (IRNSS) and other positioning systems to obtain the position information of the vehicle. The map information storage device 112 stores map information, and can obtain a navigation path leading to the destination according to the position information obtained from the positioning device 111, and display the position information and the navigation path in the map application.

[0043] exist Figure 3 In the embodiment, the environment detection device group 120 may include an on-board communication device 121, a radar 122, a laser range finder 123, a camera 124, and a light sensor 125. These devices can obtain the environment information representing the inside or outside of the vehicle.

[0044] The vehicle-mounted communication device 121 can communicate wirelessly with one or more devices directly or via a communication network. These devices that can communicate with the vehicle-mounted communication device 121 can be other vehicles, roadside machines or roadside stations, or mobile terminal devices used by the occupants of the vehicle. In some examples, the vehicle-mounted communication device 121 can use 3G cellular communication, such as code division multiple access (CDMA), EVDO, global system for mobile communications (GSM) / general packet radio service (GPRS), or 4G cellular communication, such as long term evolution (LTE), or 5G cellular communication. In some examples, the vehicle-mounted communication device 121 can also communicate with a wireless local area network (WLAN) using WiFi. In some embodiments, the vehicle-mounted communication device 121 can also communicate directly with the device using an infrared link, Bluetooth or ZigBee. In some examples, the vehicle-mounted communication device 121 can also communicate with the device using other wireless protocols.

[0045] Radar 122 is used to sense objects in the surrounding environment of the vehicle, and can also be used to sense the speed and / or direction of these objects. In some examples, radar 122 can use electromagnetic waves or lasers as a medium to detect objects based on time of flight (TOF) or phase shift, and detect the position of the detected object, the distance to the detected object, and the relative speed. In some examples, in order to be able to detect objects located in front of, behind, or to the side of the vehicle, radar 122 can be configured at an appropriate position outside the vehicle.

[0046] The laser rangefinder 123 may utilize laser light to sense objects in the environment in which the host vehicle is located. In some embodiments, the laser rangefinder 123 may include one or more laser sources, a laser scanner, and one or more detectors, among other system components.

[0047] The camera 124 can be used to capture multiple images of the surrounding environment of the vehicle. The camera 124 can be a static camera or a video camera. In some examples, in order to obtain the external image of the vehicle, the camera 124 can be located at an appropriate position outside the vehicle. For example, in order to obtain the image in front of the vehicle, the camera 124 can be configured in the interior of the vehicle close to the front windshield. Alternatively, the camera 124 can be configured around the front bumper or radiator grille. In some examples, in order to obtain the image behind the vehicle, the camera 124 can be configured in the interior of the vehicle close to the rear window glass. Alternatively, the camera 124 can be configured around the rear bumper, trunk or tailgate. In some examples, in order to obtain the image of the side of the vehicle, the camera 124 can be configured in the interior of the vehicle close to at least one of the side windows. Alternatively, the camera 124 can be configured around the side mirror, fender or door. In some examples, in order to obtain the foreground image of the vehicle in the same field of view as the driver, the camera 124 can be around the steering wheel.

[0048] The light sensor 125 can be used to detect the ambient light illumination of the vehicle. Specifically, it can be a sensor that only has the function of detecting the ambient light illumination, or it can be a sensor that has both the function of detecting the ambient light illumination and other functions (such as a rain light sensor). In some examples, in order to detect the illumination of the ambient light in the vehicle and control the interior lighting, the light sensor 125 can be configured at a position close to the reading light on the roof console. In some examples, in order to detect the illumination of the ambient light in the vehicle and control the brightness of the interior lighting and the instrument panel backlight, the light sensor 125 can be behind or inside the instrument panel. In some examples, in order to detect the ambient light entering the interior of the vehicle, the light sensor 125 can be configured on the inside of the front windshield and close to the rearview mirror. In some examples, in order to detect the ambient light entering the interior of the vehicle and determine the degree of impact on the driver, the light sensor 125 can be configured inside or outside the steering wheel. In some examples, in order to detect the illumination of the ambient light outside the vehicle and automatically adjust the anti-glare function of the rearview mirror, the light sensor 125 can be configured on the back or near the rearview mirror. In order to detect the illumination of the ambient light outside the vehicle for automatic control of the headlights, the light sensor 125 may be configured near the front bumper or front grille. In order to detect the illumination of the ambient light outside the vehicle, avoid interference from direct light or reflected light, and provide more accurate light readings, the light sensor 125 may be configured on the side or corner of the vehicle. In some advanced driver assistance systems, the light sensor 125 may be integrated with a forward-looking camera or other sensors to provide ambient light information.

[0049] exist Figure 3In the embodiment, the vehicle driving state detection device group 130 may include: a steering angle sensor 131 for detecting the steering angle of the vehicle, a vehicle speed sensor 132 for detecting the driving speed of the vehicle, and an acceleration sensor 133 for detecting the acceleration applied to the vehicle. In some examples, as shown in the dashed box, an inertial sensor 134 for detecting the position and orientation change of the vehicle based on inertial acceleration may also be included. The inertial sensor 134 may be a combination of the acceleration sensor 133 and a gyroscope in a specific implementation process.

[0050] exist Figure 3 In the embodiment, the data processing unit 140 can be implemented as a computing system having a memory, a processor, an input / output interface, and a bus connected to these. In some examples, the data processing unit 140 causes the processor to execute multiple commands through program instructions stored in the memory to process the data obtained by the navigation subsystem 110, the environment detection device group 120, and the vehicle driving state detection device group 130. In some examples, the data processing unit 140 can also partially or completely control the driving of the vehicle based on the processed data.

[0051] exist Figure 3 As shown in the dashed box, Figure 3 The projection device 170 shown, which is composed of the display control unit 150 and the display unit 160, can be implemented as a head-up display (HUD) device. Of course, the projection device can also be implemented as an enhanced display head-up display (AR-HUD) device or other devices with projection functions. The display control unit 150 can process the received data after receiving the data processed by the data processing unit 140, or after receiving the data obtained by the navigation subsystem 110, the environment detection device group 120 and the vehicle driving state detection device group 130, to obtain the display settings that need to be displayed, and project the display settings onto the windshield of the vehicle through the display unit 160 for display.

[0052] In a vehicle, taking the projection device 170 as a HUD device as an example, the projected component 204 may be a windshield. Figure 4 An exemplary top view of the vehicle is shown and Figure 5 The exemplary perspective view from the driver's seat of the vehicle shown in FIG. 1 includes a windshield 205 located at the front of the vehicle. The driver and passengers in the passenger compartment 208 of the vehicle can see the front of the vehicle through the windshield 205. Figure 3 In the embodiment of the present invention, the windshield 205 is visually located above the vehicle dashboard 206. The driver can turn the steering wheel 210 in the passenger cabin 208 to steer the vehicle, such as changing lanes, merging and parking the vehicle. In some embodiments, the steering wheel 210 can be retracted or omitted.

[0053] Projection device 170 (see Figure 1 ) projects the projected image 212 onto a portion of the windshield 205 through one or more holes (e.g., hole 216) in the instrument panel 206. Figure 5 An example size of the projected image 212 is shown, but the projected image 212 can be presented over a larger or smaller area. Examples of the projected image 212 include various vehicle information, such as the current vehicle speed, the current gear of the vehicle transmission, the engine speed, the direction of the vehicle, the current infotainment system settings, and / or other vehicle information. The projection device 170 provides information to the vehicle driver without the driver having to take their eyes off the objects in front of the vehicle.

[0054] The data 420 input to the display control unit 150 may be data processed by the data processing unit 140 , or data transmitted by the navigation subsystem 110 , the environment detection device group 120 , and the vehicle driving state detection device group 130 .

[0055] Combined with the above Figures 1 to 5 As shown, the display brightness of the projected image in the display area of ​​the windshield is affected by the brightness of the display panel. If the brightness of the display area is required to be high, the intensity of the light source on the backlight panel is increased; if the brightness of the projected image at the windshield is required to be low, the intensity of the light source on the backlight panel is reduced.

[0056] The brightness of the backlight is usually adjusted by adjusting the drive current or voltage. The brightness of the backlight can be increased or decreased by increasing or decreasing the drive current of the backlight. The brightness of the backlight can also be adjusted by changing the duration of the current received by the backlight within a certain period of time (i.e., the duty cycle). The brightness of the backlight can also be increased or decreased by increasing or decreasing the voltage across the backlight.

[0057] Moreover, within the brightness adjustment range of the backlight, the display brightness of the image partition is directly proportional to the electrical parameters of the backlight (such as the voltage, current or duty cycle mentioned above). Therefore, the corresponding electrical parameters are determined according to the display brightness of the image partition, and the backlight is driven to turn on accordingly.

[0058] Due to the complexity of the optical system of the projection device (such as HUDD, AR-HUD, etc.), although the backlights on the backlight panel are set with the same electrical parameters, due to the aging of the light source device, the brightness projected to the windshield after passing through the optical path component is lost, resulting in the actual brightness of the image partition where the projected image is located being different from the expected display brightness (that is, the set brightness value of the entire display area), and the brightness of the image partition corresponding to each backlight may also be different. For example, when a pure white image is projected onto the windshield, the backlights in the backlight panel are set with the same electrical parameters, and the brightness of each image partition measured at the windshield is less than or equal to the expected display brightness, and the brightness of each image partition may also be different. This uneven brightness display will at least affect the display effect, and when the brightness difference is large, it may cause some image elements to be blurred.

[0059] Based on the above description, the present disclosure is intended to provide a display control method that can make the brightness of image elements displayed on the windshield uniform. Figure 6 As shown, it shows an example of a display control method provided by the present disclosure, which can be executed by the aforementioned projection device 170, and in particular, can be executed by the display control unit 150 in the aforementioned projection device 170. Figure 6 The method shown includes steps S601 and S602.

[0060] In step S601, it is detected that a change in an image element displayed in a display area occurs.

[0061] Among them, the image elements are information displayed on the windshield to assist the driver in driving, such as: vehicle speed icon, navigation icon, entertainment information icon, etc.

[0062] In the projection device, the image displayed on the display panel 503 is projected onto the windshield for display. The image displayed on the display panel 503 is the same as the image displayed on the windshield, but is only proportionally enlarged. In this embodiment, the display area refers to the area where the image displayed on the display panel 503 is projected onto the windshield for display.

[0063] If at least one of the following conditions exists, it is determined that the image elements in the display area have changed: compared with the previous frame image, the next frame image has an additional image element, or the next frame image has a reduced image element, or the next frame image has a changed image element. Figure 7a As shown, the image displayed in the display area includes an image element 701 indicating speed limit information and an image element 702 for warning pedestrians. Figure 7b As shown, relative to Figure 7a , an image element 703 indicating vehicle speed is added. Figure 7c As shown, relative to Figure 7a, since the pedestrian has left the preset range of the vehicle, the image element 702 used to warn the pedestrian is reduced. Figure 7d As shown, relative to Figure 7a As the position of the pedestrian changes, the position of the image element 702 used to warn the pedestrian also changes accordingly.

[0064] Specifically, to detect whether the image elements in the display area have changed, each pixel of the two frames of images can be compared one by one. If all the pixels are the same, it is determined that there is no change, otherwise it is determined that there is a change; it can also be compared by comparing the total grayscale value or average grayscale value of the two frames of images. If they are the same, it is determined that there is no change, otherwise it is determined that there is a change; it can also be compared by comparing the hash values ​​of the two frames of images. If they are the same, it is determined that there is no change, otherwise it is determined that there is a change; it can also be compared by comparing the contours of the two frames of images. If they are the same, it is determined that there is no change, otherwise it is determined that there is a change. The present disclosure does not limit the method for detecting changes in image elements in the display area.

[0065] The display area is composed of a plurality of image partitions, including image element partitions having image elements and non-image element partitions having no image elements.

[0066] Combination Figure 2 , the backlight plate 502 includes 20 backlight lamps 501, and the corresponding display panel 503 is divided into 20 display partitions 504, and each backlight lamp 501 corresponds to a display partition 504. Since the image displayed on the display panel 503 will be projected onto the windshield, the corresponding display area at the windshield is also divided into 20 image partitions, that is, each backlight lamp corresponds to a display partition, and each display partition corresponds to an image partition. Figure 8 As shown in FIG. 8 , the display area 801 is divided into 20 image partitions. Figure 8 The X-axis direction is shown as a row, and the Y-axis direction is shown as a column. Each image partition can be identified by a coordinate, such as (2,3) indicates an image partition in the second row and third column. Among them, there are image element partitions: image element 701 falls into the image partition in the third row and fourth column, image element 702 falls into the first row and third column, and image partition in the second row and third column.

[0067] Some possible ways to determine the image element partitions are that since the position of each backlight is fixed, the display partition on the display panel corresponding to each backlight is also fixed, and the image partition of each display partition at the windshield is also fixed. Add a mark to each display partition, such as Figure 8 For a frame of image to be displayed, the identifier of the display partition into which the image elements included in the frame of image fall is determined, and then the partition with the image elements is determined according to the identifier of the display partition.

[0068] In some other achievable manners, if an image element exists in an image partition of the display area, the grayscale value of the partition is not 0, and if an image element does not exist in the image partition, the grayscale value of the partition is 0. Therefore, the average grayscale value of the pixels included in each image partition can be determined, and the image partition with an average grayscale value not 0 is determined as a partition with an image element.

[0069] In some other achievable methods, in a frame of image, some areas may not have image elements, and their grayscale values ​​should be 0, but due to errors in the image transmission process (such as transmission errors) or design errors (theoretically it is black when drawing, but the set pixel value is not 0), the grayscale value is not 0. Therefore, in order to avoid mistakenly turning on the backlight of the image partition whose grayscale value should be 0 but is not 0 due to the error, after determining the average grayscale value of the pixels included in each image partition; the image partition whose average grayscale value is greater than or equal to the grayscale threshold is determined as a partition with image elements. The grayscale threshold is usually set to a grayscale value that cannot be distinguished by the human eye, such as below 20. The human eye observes the image displayed below the grayscale threshold as indistinguishable black. In this way, image partitions without image elements but with grayscale values ​​greater than 0 and less than the grayscale threshold can be eliminated, thereby preventing the backlight corresponding to the image partition without image elements from being turned on (i.e., a certain image partition has no image elements, but because the backlight of this image partition is turned on, the human eye observes that this image partition is brighter than other image partitions without image elements), which affects the driver's driving.

[0070] The first image partition may be a partition in the display area where image elements added in a frame image after the change are located relative to a frame image before the change, or may be a partition where image elements whose positions are changed in a frame image after the change are located relative to a frame image before the change.

[0071] by Figure 8 Taking a frame of image before the image element changes as an example, the image element is increased in the display area compared with before the change. Fig. 9 As shown, the image elements included in the display area after the change are: image element 701, image element 702 and image element 703, then the first image partition includes: the image partition of the third row and the first column and the third row and the second column to which image element 703 belongs; there are image element partitions: the image partition of the third row and the fourth column to which image element 701 belongs, the image partition of the first row and the third column and the second row and the third column to which image element 702 belongs, and the image partition of the third row and the first column and the third row and the second column to which image element 703 belongs.

[0072] by Figure 8 Taking the image before the image element changes as an example, the position of the image element in the display area changes. Fig.10As shown, the image elements included in the display area after the change are: image element 701, image element 702 and image element 703, but the image element 702 is changed in position relative to the position before the change, and the image element 703 is added, so the first image partition determined accordingly includes: the image partition of the first row and second column to which the image element 702 belongs, and the image partition of the third row, first column and third row, second column to which the image element 703 belongs. The image element partitions are: the image partition of the third row and fourth column to which the image element 701 belongs, the image partition of the first row and second column to which the image element 702 belongs, and the image partition of the third row, first column and third row, second column to which the image element 703 belongs.

[0073] In step S602, the electrical parameters of the backlight corresponding to the target image partition in the display area are controlled so that the brightness difference between the first image partition included in the target image partition and the second image partition is less than a set difference threshold.

[0074] The target image partition may include only the first image partition, or may include the first image partition and the second image partition, that is, the target image partition may be the first image partition, or may be a partition with image elements.

[0075] When the target image partition is the first image partition, the compensated display brightness of each first image partition is determined according to the brightness compensation coefficient of each first image partition and the expected display brightness of the display area; and the electrical parameters of the backlight corresponding to the first image partition in the display area are controlled according to the compensated display brightness of each first image partition.

[0076] In the case where the target image partition is a partition with image elements (i.e., a first image partition and a second image partition), the compensated display brightness of each partition with image elements is determined according to a brightness compensation coefficient of each partition with image elements and a desired display brightness of the display area; and the electrical parameters of the backlight corresponding to each partition with image elements in the display area are controlled according to the compensated display brightness of each partition with image elements.

[0077] The brightness compensation coefficient is determined based on the difference between the brightness of the reference image partition and the brightness of the remaining image partitions. The brightness compensation coefficient of each image partition is pre-stored in the vehicle. After determining the image partition to which the image element belongs, the brightness value of each image partition is determined based on the overall brightness value of the display area currently set, that is, the expected display brightness, and the brightness compensation coefficient of each image partition. For example, if the expected display brightness of the current display area is 100, and the brightness compensation coefficient of a certain image partition is 0.92, the compensated display brightness after compensation is 92.

[0078] The reference image partition is a partition determined from various image partitions during the test phase. For example, a pure white image is projected, and the brightness values ​​of various image partitions in the display area are measured at the windshield. The brightness values ​​are sorted from large to small, and the median value in the middle is determined. Any image partition with a brightness value less than or equal to the median value is determined as the reference image partition. It should be noted that the reference image partition is usually unchanged after being determined.

[0079] Optionally, the expected display brightness is determined according to the ambient light value, and the corresponding relationship between the ambient light value and the brightness is pre-stored in the vehicle. For a certain ambient light value that is not stored, the corresponding brightness value is determined by linear interpolation. Alternatively, the expected display brightness is determined according to the brightness level, and the brightness corresponding to different brightness levels is pre-stored in the vehicle. When the user selects a brightness level, the brightness value of the display area is changed to the brightness value corresponding to the level. Alternatively, the expected display brightness is determined according to the ambient light value and the brightness level, and the corresponding relationship between the ambient light value and the brightness range is pre-stored in the vehicle. Similarly, if a certain ambient light value that is not stored is determined by linear interpolation, the corresponding brightness range is determined by linear interpolation. The brightness value of the expected display brightness is: the sum of the minimum value of the brightness range and the brightness value determined by the brightness level, and the brightness value determined by the brightness level is: the product of the difference between the maximum and minimum values ​​in the brightness range and the ratio of the selected brightness level to the total brightness level. For example: there are three brightness levels, namely level 1, level 2 and level 3. The brightness range corresponding to the ambient light value 1 is (minimum value A, maximum value B). The current ambient light value is detected to be ambient light value 1, and the brightness level set by the user is level 2. The current brightness value is: minimum value A+2(minimum value A-maximum value B) / 3.

[0080] It should be noted that when the brightness difference between two image partitions is within the difference threshold, the human eye cannot distinguish them. For example, when a pure white image is projected, although there is a difference in the brightness of the two image partitions, the difference is within the difference threshold. At this time, the brightness of the two image partitions observed by the human eye is the same.

[0081] The target image partition is the first image partition, and the electrical parameters of the backlight corresponding to the first image partition in the display area are controlled. Specifically, for an image element that exists in both the frame image before the change and the frame image after the change, and the position of the image element has not changed, the brightness of the image partition to which the image element belongs has been adjusted when displaying the frame image before the change, that is, the backlight corresponding to the image partition (the second image partition) has been turned on at the required brightness. Therefore, after the change, the brightness of the image partition where the image element is located does not need to be adjusted again, but only the brightness of the image element whose position has changed in the frame image after the change relative to the frame image before the change and the image partition where the added image element is located (the first image partition) is adjusted. In this way, there is no need to make redundant adjustments for those that have already been adjusted, thereby improving adjustment efficiency.

[0082] The target image partition is a partition with image elements, and the electrical parameters of the backlight corresponding to the partition with image elements in the display area are controlled. Specifically, the image partition where all the displayed image elements in the display area are located, that is, the image partition where the image elements are located, is determined, and the brightness of the image partition is adjusted so that the brightness of all image partitions with image elements is uniform.

[0083] The adjustment efficiency of adjusting only the electrical parameters of the backlight corresponding to the first image partition is high, but it is necessary to change the image frame after the change and the image frame before the change to determine the changed image elements, so it requires high computing power. However, when adjusting the electrical parameters of the backlight corresponding to the image element partition, there is no need to compare the two image frames before and after the change, and all image elements displayed in the image frame after the change can be directly determined, so the computing power requirement is low. The adjustment strategy can be flexibly selected according to actual requirements.

[0084] In this way, when there is a change in the image elements in the display area, the brightness of the image partition is adjusted so that the brightness difference between the partition to which the changed image elements belong and the image partition to which the image elements have not changed is less than the difference threshold, that is, the brightness of each image partition is uniform, thereby ensuring that the image elements can be displayed clearly and improving the driving experience.

[0085] Optionally, image elements that need to be highlighted are determined in advance, such as image elements indicating speeding, image elements indicating low fuel or battery level, etc. When it is detected that an image element that needs to be highlighted is displayed in an image partition, a certain brightness can be compensated again after compensation through a brightness compensation coefficient, or the highest brightness can be directly set to highlight the image partition where the important image element is located, ensuring that the driver can pay immediate attention to it.

[0086] In order to avoid the situation where the image element does not exist after the change, but the backlight corresponding to the image partition is still turned on to affect the driver's driving, the backlight corresponding to the image partition is turned off. Figure 6 ,like Fig.11 As shown, the method also includes the following step S603.

[0087] In step S603, the backlight corresponding to the third image subarea in the display area where the image element exists before the change but does not exist after the change is controlled to be turned off.

[0088] by Figure 8 Take the image before the image element changes as an example. Fig.12 As shown, since the pedestrian has left the observation area of ​​the vehicle, the image element 702 does not exist in the display area after the change, and therefore, the backlights corresponding to the image partitions in the first row and third column and the second row and third column to which the image element 702 belongs before the change are turned off.

[0089] It should be noted that, when the third image partition corresponding to an image element that existed before the change in the display area and does not exist after the change overlaps with the first image partition corresponding to an image element that is newly added after the change or an image element that changes its position, the processing method of the overlapping image partition may be: turning off the corresponding backlight in accordance with the processing method corresponding to the third image partition, and then determining the brightness and controlling the corresponding backlight to turn on in accordance with the processing method corresponding to the first image partition; or the backlight of the overlapping image partition may remain at the original setting unchanged.

[0090] by Figure 8 Take the image before the image element changes as an example. Fig.13 As shown, since the pedestrian has left the observation area of ​​the vehicle, the image element 702 does not exist in the display area after the change, but since the front vehicle has entered the observation area of ​​the vehicle, a prompt box for prompting the front vehicle, i.e., image element 704, is added. The third image partition determined according to the image element 702 before the change is: the image partitions of the first row and the third column and the second row and the third column, and the first image partition determined according to the newly added image element 704 after the change is: the image partitions of the first row and the third column and the first row and the fourth column, i.e., the image partition of the first row and the third column is both the first image partition and the second image partition, and the backlight corresponding to the image partition of the first row and the third column can be turned off first, and then the backlight can be controlled to turn on according to the determined brightness value, or the corresponding backlight setting can be kept unchanged.

[0091] In some embodiments of the present disclosure, Figure 6 ,like Fig.14 As shown, the method also includes the following steps S604 and S605.

[0092] In step S604, the backlights in the display area are controlled to be turned on with the same electrical parameters, and a test image is projected onto the display area.

[0093] In step S605, a brightness compensation coefficient of each image subarea is determined according to a difference between the brightness of the reference image subarea at the display area and the brightness of each image subarea.

[0094] The test image is usually a pure color image, such as pure white, pure red, etc. All backlights are driven with the same electrical parameters. After the test image is projected onto the windshield, the brightness value of each image partition at the windshield is detected (such as using a brightness tester), and the ratio of the reference image partition to each image partition is determined as the brightness compensation coefficient of each image partition.

[0095] Exemplarily, all backlights are turned on with the same electrical parameters, the detected brightness value of the reference image partition is 10000, and the brightness of other image partitions are 9990, 10000, and 10020 respectively, and the corresponding brightness compensation coefficients are: 1000 / 999, 1,500 / 501.

[0096] Since the same image partition has the same brightness, the images of different colors may also have different brightness. Therefore, in order to adjust the brightness more accurately, a set of corresponding brightness compensation coefficients is stored for pure color images of different colors, such as: white, image partition 1-1000 / 999, image partition 2-1, image partition 3-500 / 501, red, image partition 1-1001 / 998, image partition 2-1, image partition 3-1001 / 101. That is, for the same image partition, the brightness compensation coefficients corresponding to different colors are also different.

[0097] Accordingly, when the image element changes, the main color of the changed image element is analyzed, and the corresponding brightness compensation coefficient is determined according to the main color of the image element and the image partition to which it belongs, and then the brightness value of the image partition is determined according to the brightness compensation coefficient and the current brightness. For example, if the main color of the currently displayed image element is white and the image partition to which it belongs is image partition 1, the brightness compensation coefficient is 1000 / 999; if the main color of the currently displayed image element is red and the image partition to which it belongs is image partition 1, the brightness compensation coefficient is 1001 / 998.

[0098] In some embodiments of the present disclosure, the method further includes the following step S609.

[0099] In step S609, when the change in the ambient light value is greater than the change threshold, and / or the brightness level changes, the expected display brightness of the display area is updated.

[0100] The ambient light value includes the ambient light value inside the vehicle and the ambient light value outside the vehicle that affect the display effect of the display area. The ambient light value can be detected by a light sensor 125 provided on the vehicle. The brightness level is a different brightness level set in the vehicle that allows the user to adjust the brightness of the display area. The number of levels varies depending on the vehicle.

[0101] The display effect of the display area will be affected by the ambient light value. Taking the display area corresponding to the HUD as an example, when the vehicle drives from the underground garage to the outside of the garage, the ambient light value increases, and the display brightness of the HUD needs to be increased accordingly; when the vehicle is driving at night, the ambient light value outside the vehicle is small, and the display brightness of the HUD needs to be lowered accordingly; when the vehicle is driving at night, the ambient light value outside the vehicle is small, but the lights inside the car are turned on, and the display brightness of the HUD needs to be increased accordingly so that the displayed information can be seen clearly. Therefore, when the ambient light value changes, it is necessary to adjust the display brightness of the HUD, that is, adjust the size of the electrical parameters of the backlight. Another situation is that the user perceives that the display brightness of the HUD is too high or too low, and manually adjusts the brightness level of the HUD.

[0102] Therefore, if the ambient light value changes or the user adjusts the brightness level, it is necessary to recalculate the brightness of each image partition based on the adjusted brightness and the brightness compensation coefficient of each image partition, and each image partition controls the electrical parameters of the corresponding backlight according to the recalculated brightness.

[0103] Based on the same inventive concept as the above technical solution, see Fig.15 , which shows a display control device 1500 provided by the present disclosure, the device 1500 may be Figure 1 , Figure 4 The display control unit shown in the figure, the device 1500 includes: a control part 1501;

[0104] The control part 1501 is configured to control the electrical parameters of the backlight corresponding to the target image partition in the display area when it is detected that the image elements displayed in the display area have changed, so that the brightness difference between the first image partition included in the target image partition and the second image partition is less than a set difference threshold, wherein the first image partition is a partition in the display area where the image element change occurs, and the second image partition is a partition in the display area where there is image element and no image element change occurs.

[0105] In some embodiments, the device also includes a determination part; the determination part is configured to determine the partition to which the image elements added in the display area relative to before the change and the image elements with changed positions belong as the first image partition when a change is detected in the image elements displayed in the display area.

[0106] In some embodiments, the control part 1501 is further configured to control the backlight corresponding to the third image partition in the display area where the image element exists before the change but does not exist after the change to be turned off.

[0107] In some embodiments, the control part 1501 is also configured to control the backlight of the display area to turn on with the same electrical parameters and project the test image onto the display area; the determination part is also configured to determine the brightness compensation coefficient of each image partition based on the detected brightness difference between each image partition projected with the test image and the brightness of the reference image partition.

[0108] In some embodiments, the control part 1501 is specifically configured to determine the compensated display brightness of each target image partition according to the brightness compensation coefficient of each target image partition and the expected display brightness of the display area when a change in the image elements displayed in the display area is detected; and control the electrical parameters of the backlight corresponding to each target image partition in the display area according to the compensated display brightness of each target image partition.

[0109] In some embodiments, the device also includes an update portion, which is configured to update the expected display brightness of the display area when the change in the ambient light value is greater than a change threshold and / or the brightness level changes, and the expected display brightness is determined based on the ambient light value and / or the brightness level.

[0110] In some embodiments, the target image partition also includes: a second image partition, a determination part, and is also configured to determine the average grayscale value of the pixels included in each image partition when a change is detected in the image elements displayed in the display area; and determine the image partition whose average grayscale value is greater than or equal to the grayscale threshold as the target image partition.

[0111] refer to Fig.16 , which shows a structural block diagram of a display control device 1600 provided by an exemplary embodiment of the present disclosure. In some examples, the display control device 1600 has a communication function and can access a wired network or a wireless network. In some examples, the display control device 1600 can receive data based on the wired network or wireless network accessed. It can be understood that the display control device 1600 undertakes the calculation and processing work of the technical solution of the present disclosure, and the present disclosure does not limit this.

[0112] like Fig.16 As shown, the display control device 1600 in the present disclosure may include one or more of the following components: one or more processors 1610 and a memory 1620 .

[0113] Optionally, the processor 1610 uses various interfaces and lines to connect various parts of the entire display control device 1600, and executes various functions and processes data of the display control device 1600 by running or executing instructions, programs, code sets or instruction sets stored in the memory 1620, and calling data stored in the memory 1620. Optionally, the processor 1610 can be implemented in at least one hardware form of digital signal processing (DSP), field-programmable gate array (FPGA), and programmable logic array (PLA). The processor 1610 can integrate one or a combination of a central processing unit (CPU), a graphics processing unit (GPU), a neural network processor (NPU), and a baseband chip. Among them, the CPU mainly processes the operating system, user interface, and application programs; the GPU is responsible for rendering and drawing the content to be displayed on the touch display screen; the NPU is used to implement artificial intelligence (AI) functions; and the baseband chip is used to process wireless communications. It is understandable that the above-mentioned baseband chip may not be integrated into the processor 1610, but may be implemented by a separate chip.

[0114] The memory 1620 may include a random access memory (RAM) or a read-only memory (ROM). Optionally, the memory 1620 includes a non-transitory computer-readable storage medium. The memory 1620 may be used to store instructions, programs, codes, code sets, or instruction sets. The memory 1620 may include a program storage area and a data storage area, wherein the program storage area may store instructions for implementing an operating system, instructions for at least one function (such as a touch function, a sound playback function, an image playback function, etc.), instructions for implementing the above various method embodiments, etc.; the data storage area may store data created according to the use of the display control device 1600, etc.

[0115] In addition, those skilled in the art can understand that the structure of the display control device 1600 shown in the above drawings does not constitute a limitation on the computing device, and the display control device 1600 may include more or fewer components than shown, or combine certain components, or arrange the components differently. For example, the display control device 1600 also includes a display screen, a camera assembly, a microphone, a speaker, a radio frequency circuit, an input unit, a sensor (such as an acceleration sensor, an angular velocity sensor, a light sensor, etc.), an audio circuit, a WiFi module, a power supply, a Bluetooth module and other components, which will not be described in detail here.

[0116] The present disclosure also provides a projection device, which includes: a display control unit and a display unit; the display control unit is configured to control the electrical parameters of the backlight corresponding to the target image partition in the display area when a change in the image elements displayed in the display area is detected, so that the brightness difference between the first image partition included in the target image partition and the second image partition is less than a set difference threshold, wherein the first image partition is a partition in the display area where the image element change occurs, and the second image partition is a partition in the display area where the image element exists and no image element change occurs; the display unit is configured to enable a visual confirmer to visually confirm the image by projecting the image onto the projected component.

[0117] The present disclosure also provides a brightness adjustment system 1700, such as Fig.17 As shown, it includes: a CAN bus transceiver 1701, a processor unit 1702, a backlight driver 1703, and a backlight 501; the processor unit 1702 includes: a CAN bus data transceiver module 1710, a data processing module 1711, a brightness calculation module 1712, a backlight drive control module 1713, and a memory 1714.

[0118] The CAN bus transceiver 1701 is used to convert the differential signal of the CAN bus into a TTL level, so as to match the input level of the CAN bus data transceiver module 1710 in the processor unit 1702, so that the CAN bus data transceiver module 1710 in the processor unit 1702 can correctly receive data from the CAN bus and send data to the CAN bus. The processor unit 1702 is used to receive signals such as the ambient light value and the brightness level from the CAN bus through the CAN bus data transceiver module 1710. The data processing module 1711 calculates the expected display brightness according to the ambient light value and / or the brightness level; the brightness calculation module 1712 obtains the brightness compensation coefficient corresponding to the image partition from the memory 1714, calculates the brightness value of each target image partition according to the brightness compensation coefficient and the expected display brightness, and converts the brightness value into an electrical parameter; the backlight drive control module 1713 controls the backlight driver 1703 to start according to the electrical parameter, thereby driving the backlight 501 to turn on.

[0119] The present disclosure also provides a computer-readable storage medium, which stores at least one instruction, and the at least one instruction is used to be executed by a processor to implement the display control method described in the above embodiments.

[0120] The present disclosure also provides a computer program product, which includes computer instructions stored in a computer-readable storage medium; a processor of a computing device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computing device executes to implement the display control method described in the above-mentioned embodiments.

[0121] Those skilled in the art should be aware that in one or more of the above examples, the functions described in the present disclosure can be implemented using hardware, software, firmware, or any combination thereof. When implemented using software, these functions can be stored in a computer-readable medium or transmitted as one or more instructions or codes on a computer-readable medium. Computer-readable media include computer storage media and communication media, wherein communication media include any media that facilitates the transmission of computer programs from one place to another. Storage media can be any available media that can be accessed by a general or special-purpose computer.

[0122] It should be noted that the technical solutions described in the present disclosure can be combined arbitrarily without conflict.

[0123] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A display control method, characterized in that: The method comprises: In the case where a change in an image element displayed in a display area is detected, the electrical parameters of a backlight corresponding to a target image partition in the display area are controlled according to a desired display brightness of the display area and a brightness compensation coefficient of the target image partition, so that a brightness difference between a first image partition and a second image partition included in the target image partition is less than a set difference threshold, wherein the first image partition is a partition in the display area to which image elements that have been added and image elements whose positions have changed belong relative to those before the change, and the second image partition is a partition in the display area to which image elements have been added and to which no change has occurred.

2. The method according to claim 1, characterized in that The method further comprises: The backlight corresponding to the third image subarea in the display area where the image element exists before the change but does not exist after the change is controlled to be turned off.

3. The method according to claim 1 or 2, characterized in that: The method further comprises: Controlling the backlight of the display area to turn on with the same electrical parameters, and projecting a test image onto the display area; A brightness compensation coefficient of each image partition is determined according to the detected brightness difference between each image partition on which the test image is projected and the brightness of the reference image partition.

4. The method according to claim 1, characterized in that: When a change is detected in an image element displayed in a display area, controlling the electrical parameters of a backlight corresponding to a target image partition in the display area according to a desired display brightness of the display area and a brightness compensation coefficient of the target image partition, comprises: When a change in an image element displayed in the display area is detected, determining a compensated display brightness of each target image partition according to a brightness compensation coefficient of each target image partition and a desired display brightness of the display area; According to the compensated display brightness of each target image partition, the electrical parameters of the backlight corresponding to each target image partition in the display area are controlled.

5. The method according to claim 4, characterized in that The method further comprises: When the change in the ambient light value is greater than a change threshold and / or the brightness level changes, the expected display brightness of the display area is updated, and the expected display brightness is determined according to the ambient light value and / or the brightness level.

6. The method according to claim 1, characterized in that The target image partition further includes: a second image partition, and the method further includes: In the case where a change in the image element displayed in the display area is detected, determining an average grayscale value of the pixels included in each image partition; An image partition whose average grayscale value is greater than or equal to the grayscale threshold is determined as the target image partition.

7. A display control device, characterized in that: The device comprises: a control part; The control part is configured to control the electrical parameters of the backlight corresponding to the target image partition in the display area according to the expected display brightness of the display area and the brightness compensation coefficient of the target image partition when a change is detected in the image elements displayed in the display area, so that the brightness difference between the first image partition included in the target image partition and the second image partition is less than a set difference threshold, wherein the first image partition is the partition in the display area to which the image elements added and the image elements with changed positions belong relative to before the change, and the second image partition is the partition in the display area where there are image elements and no image element changes occur.

8. A display control device, characterized in that: The device comprises: a processor and a memory; the processor is used to execute instructions stored in the memory to implement the display control method according to any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores at least one instruction, and the at least one instruction is used to be executed by a processor to implement the display control method according to any one of claims 1 to 6.

10. A projection device, characterized in that: include: A display unit and a display control unit; The control unit is configured as follows: In the case where it is detected that the image elements displayed in the display area have changed, the electrical parameters of the backlight corresponding to the target image partition in the display area are controlled according to the expected display brightness of the display area and the brightness compensation coefficient of the target image partition, so that the brightness difference between the first image partition included in the target image partition and the second image partition is less than a set difference threshold, wherein the first image partition is the partition in the display area to which the image elements added and the image elements with changed positions belong relative to before the change, and the second image partition is the partition in the display area to which the image elements have been added and the image elements have not been changed; The display unit projects an image onto a projection target member so that a viewer can visually view the image.

Images