Method for managing image data and automotive lighting device

Abstract

The present invention provides a method for managing image data in an automotive lighting device (10). The method comprises the steps of providing a first image pattern (1) and providing a second image pattern (2), the first image pattern being sent to a lighting module. A difference pattern (20) is generated by subtracting the second image pattern from the first image pattern, and the difference pattern (20) is sent to the lighting module (4), so that the lighting module (4) can reconstruct the second image pattern (2) based on the data of the first image pattern (1) and the difference pattern (20). The present invention also provides an automotive lighting device (10) for performing the steps of the method.

Description

Technical Field

[0001] The present invention relates to the field of automotive lighting equipment and more particularly to managing electronic data obtained from light source control. Background Art

[0002] Current lighting installations include an increasing number of light sources that must be controlled to provide adaptive lighting functionality.

[0003] This number of light sources involves a large amount of data that must be managed by the control unit. The CAN protocol—one of its variants (CAN-FD being one of the most common)—is typically used to transmit data between the PCM and the light modules. However, some car manufacturers have decided to limit the bandwidth of the CAN protocol, which impacts management operations, which typically require around 5Mbps.

[0004] In fact, when the system processes images in motion, the issue of saving data size is crucial because it affects the speed of data transmission and, therefore, the speed of image projection.

[0005] A solution to this issue is currently being sought. Summary of the Invention

[0006] The present invention provides a solution to these problems by means of a method and an automotive lighting device for managing image data.Preferred embodiments of the invention are defined in the dependent claims.

[0007] Unless otherwise defined, all terms (including technical and scientific terms) used herein are to be interpreted according to customary usage in the art. It will be further understood that commonly used terms are to be interpreted according to customary usage in the relevant art and are not to be interpreted in an idealized or overly formal sense unless expressly defined herein.

[0008] In this document, the term "comprises" and its derivatives (such as "comprising", etc.) should not be understood in an exclusive sense, that is, these terms should not be interpreted as excluding the possibility that the described and defined content may include other elements, steps, etc.

[0009] In a first aspect, the present invention provides a method for managing image data in an automotive lighting device, the method comprising the following steps:

[0010] - providing a first image pattern, the first image pattern comprising a plurality of pixels, wherein each pixel is characterized by a value related to a luminous intensity of the pixel;

[0011] - sending the first image pattern to the light emitting module;

[0012] - providing a second image pattern, the second image pattern comprising a plurality of pixels, wherein each pixel is characterized by a value related to a luminous intensity of the pixel;

[0013] - generating a difference pattern, the difference pattern being obtained by subtracting the second image pattern from the first image pattern; and

[0014] - sending the difference pattern to the lighting module, so that the lighting module can reconstruct the second image pattern based on the data of the first image pattern and the difference pattern.

[0015] The method aims to manage the image data exchanged between a control unit and a lighting module. The control unit is responsible for calculating the difference pattern and can be located anywhere in the motor vehicle, not necessarily physically inside the lighting device. The lighting module is designed to provide the light pattern for illumination or signaling and is located inside the lighting device.

[0016] The main advantage of this method is that it reduces the size of the data set to be sent to the lighting module. This is extremely useful in the case of ADB (Adaptive High Beam) or DBL (Dynamic Bending Lights), where the difference between one frame and the next is small. Sometimes it is not necessary to compress the image because the data size is small enough to be transmitted without compression.

[0017] In some specific embodiments, the light pixels of the image pattern are grayscale pixels, and more specifically, the luminous intensity of each pixel is scaled from 0 to 255.

[0018] Light modules typically define light patterns in grayscale, where the light intensity levels range from 0 to 255. This is a way to quantize the light pattern so that it can be converted into light data and then transmitted and managed by the vehicle's control unit.

[0019] In some specific embodiments, the method further comprises the step of buffering the first image in the lighting module.

[0020] When the first image is buffered, it is easy to prepare subsequent images based on the provided difference pattern.

[0021] In some specific embodiments, the method further comprises the following steps:

[0022] - normalizing the difference pattern by adding a compensation value to at least some pixels of the difference pattern such that a lower value of the normalized difference pattern is equal to or greater than zero;

[0023] - sending the compensation value to the lighting module; and

[0024] - Restoring the difference pattern by subtracting the compensation value from the normalized difference pattern.

[0025] These steps are useful in situations where there are changes involving increases and decreases in intensity, such as in the case of DBL.

[0026] In some specific embodiments, the method further comprises the following steps:

[0027] - applying an absolute value function ABS to the difference pattern, thereby generating a modified difference pattern;

[0028] - sending the modified difference pattern to the light emitting module; and

[0029] - applying the absolute value function ABS to the second image pattern after reconstructing the second image pattern from the first image pattern and the modified difference pattern.

[0030] These steps are useful in cases where there are changes involving movement of black areas, such as in the case of ADB.

[0031] In some specific embodiments, the method further comprises the following steps:

[0032] - compressing at least a portion of the difference pattern before sending it to the light emitting module, thereby creating compressed data; and

[0033] - decompressing the compressed data by the lighting module.

[0034] Sometimes it is not necessary to compress the entire difference pattern because some intensity values ​​are zero. Therefore, only the meaningful values ​​are compressed.

[0035] In some specific embodiments, compressing at least a portion of the difference pattern affects less than 20% of the difference pattern area.

[0036] In these cases, representative values ​​lie within the outlines of the black region, so there is no need to compress the larger portion.

[0037] This cropping step is useful when large parts of the image are completely dark, so that the compression stage focuses only on the parts that contain representative values.

[0038] In a second aspect of the invention, the present invention provides a lighting device, comprising:

[0039] - a lighting module comprising a plurality of light sources; and

[0040] - A control unit for executing the steps of the method according to the first inventive aspect.

[0041] Such lighting devices are capable of operating at a lower bandwidth than traditional lighting devices.

[0042] In some specific embodiments, the lighting module further includes a processor unit configured to decompress the compressed data.

[0043] By using a decompression stage in the appropriate light-emitting module, the bandwidth is narrowed down to the module itself.

[0044] In some specific embodiments, the control unit and the processor unit both include an image buffer for storing the first image.

[0045] In some specific embodiments, the light sources are solid-state light sources, such as LEDs.

[0046] The term "solid-state" refers to light emitted through solid-state electroluminescence, which uses semiconductors to convert electricity into light. Compared to incandescent lighting, solid-state lighting produces visible light with less heat generation and less energy dissipation. The generally smaller mass of solid-state electronic lighting devices provides greater shock and vibration resistance compared to fragile glass tubes / bulbs and long, thin filaments. Solid-state light sources also eliminate filament evaporation, thereby potentially increasing the life span of the lighting device. Some examples of these lighting types include semiconductor light emitting diodes (LEDs), organic light emitting diodes (OLEDs), or polymer light emitting diodes (PLEDs) as the illumination source, rather than electrical filaments, plasmas, or gases. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] To complete the description and to facilitate a better understanding of the present invention, a set of drawings is provided. The drawings constitute an integral part of the description and illustrate embodiments of the present invention, which should not be construed as limiting the scope of the present invention but merely as examples of how the present invention may be implemented. The drawings include the following:

[0048] [ Figure 1 ] shows a first photometric image of the high beam module projected by the vehicle lighting device according to the invention.

[0049] [ Figure 2 ] shows the representation [ Figure 1 ] is a portion of the photometric pixel matrix.

[0050] [ Figure 3 ] shows a portion of a second pixel matrix, which corresponds to the second image of the first embodiment of the method according to the invention.

[0051] [ Figure 4 ] shows a part of a difference matrix, which corresponds to an intermediate image according to a first embodiment of the method according to the invention.

[0052] [ Figure 5 ] shows a part of a temporary matrix, which corresponds to an intermediate image according to a first embodiment of the method according to the invention.

[0053] [ Figure 6 ] shows a part of a normalized difference matrix, which corresponds to an intermediate image according to a second embodiment of the method according to the invention.

[0054] [ Figure 7 ] shows an automotive lighting device according to the present invention.

[0055] Throughout the drawings and detailed description, elements of the example embodiments are represented by the same reference numerals where appropriate:

[0056] 1 First image pattern

[0057] 11 pixels of the first image pattern

[0058] 2 Second image pattern

[0059] 21 pixels of the second image pattern

[0060] 3 Black Area

[0061] 4 Light-emitting modules

[0062] 5LED

[0063] 6 Control Unit

[0064] 7 Processor Units

[0065] 10. Automotive lighting equipment

[0066] 20 Difference Matrix

[0067] 100 motor vehicles DETAILED DESCRIPTION

[0068] The exemplary embodiments are described in sufficient detail to enable one of ordinary skill in the art to implement and realize the systems and processes described herein.It is important to understand that the embodiments may be provided in many alternative forms and should not be construed as limited to the examples set forth herein.

[0069] Therefore, although the embodiments may be modified in various ways and take various alternative forms, specific embodiments thereof are shown in the drawings and described in detail below as examples. There is no intention to be limited to the particular forms disclosed. On the contrary, all modifications, equivalents, and alternatives falling within the scope of the appended claims are intended to be included.

[0070] [ Figure 1] shows a first photometric image of the high beam module to be projected by the vehicle lighting device according to the invention.

[0071] The first image may be divided into pixels, and each pixel may be characterized by its luminous intensity, which is scaled from 0 (corresponding to black) to 255 (corresponding to white).

[0072] This image corresponds to an Adaptive Driving Beam (ADB) image and includes a black area 3 that extends across the image to keep vehicles traveling in the opposite lane out of the reach of the high beam.

[0073] This first image is sent to the lighting module and buffered therein so that the remaining subsequent images can be reconstructed based on the previous image.

[0074] [ Figure 2 ] shows a part of such a pixel matrix, called image pattern 1. Each pixel 11 of the image pattern 1 is characterized by a number, which is in accordance with the above-mentioned scale.

[0075] In this example, for the sake of clarity, this black area 3 is represented by only four pixels, which does not correspond to a realistic approach, but the correspondence to real-life images is direct.

[0076] [ Figure 3 ] shows a portion of a second pixel matrix 2 having pixels 21 corresponding to a second image of the ADB. As can be seen in this image, the black region 3 has moved to the left, so that it now affects different pixels, and different luminescence values ​​now appear to the right of the black region 3, which correspond to the original light pattern.

[0077] [ Figure 4 ] shows a portion of a difference matrix 20, which is the result of subtracting the second image pattern from the first image pattern. The difference matrix will have many zeros because the only difference between the first and second image patterns is the left and right boundaries of the black area.

[0078] The next step is to transmit the modified difference matrix to the lighting module and reconstruct the second image based on the buffered first image and the transmitted modified difference matrix.

[0079] The modified difference matrix is ​​a matrix obtained by applying the ABS function to the difference matrix. Through this operation, all values ​​of the modified difference matrix are positive and are easier to transmit.

[0080] The transmission can be compressed or uncompressed.

[0081] [ Figure 5] shows a portion of a temporary matrix obtained in the lighting module by subtracting the modified difference matrix from the cached first image. The temporary matrix is ​​almost equal to the second pattern, but has some negative values.

[0082] The final second image pattern is restored by applying the ABS function to the temporary matrix so that the second image pattern can be projected by the lighting module.

[0083] There is a second embodiment of the method according to the invention. [ Figure 1 ]arrive[ Figure 4 ] The steps are the same, and the difference matrix is ​​calculated.

[0084] However, in this second embodiment, the ABS function is not applied to the difference matrix, but the compensation value is added to all non-zero values ​​in the difference matrix to obtain a normalized difference matrix, as shown in [ Figure 6 In this normalized difference matrix, all values ​​are greater than or equal to zero, which is achieved in a different way from the previous embodiment of the method.

[0085] The compensation value is chosen by taking the ABS value of the minimum value of the original difference matrix and adding 1. In this case, the minimum value is -60, the ABS value is 60, and the compensation value is 61 (to avoid leaving zero values ​​in pixels that have meaningful values).

[0086] Although this second embodiment is shown to have some of the same steps as the previous embodiment, it is particularly advantageous for other applications such as dynamic bending lights (DBL) where the symbol information is important because there is no black area moving along the image, but the image outline itself moves to the left or right. However, for convenience, [ Figure 1 ]to[ Figure 4 ] is used to explain the second embodiment.

[0087] Following this second embodiment, the normalized difference matrix and the compensation values ​​are sent (in compressed or uncompressed form) to the lighting module where the second image is restored by subtracting the compensation values ​​from the normalized difference matrix and the difference matrix from the first image.

[0088] The end result is the same. The choice of each embodiment depends on the lighting function.

[0089] The data transmission rate of this method is significantly lower than other methods. In fact, the data can be transmitted in a compressed or uncompressed form. In any case, the data transmission rate is sufficient to meet the requirements of some car manufacturers, so this data can be sent to light modules with bandwidth restrictions.

[0090] [ Figure 7] shows an automotive lighting device according to the present invention, the lighting device comprising:

[0091] - a lighting module 4 comprising a plurality of LEDs 5;

[0092] - a control unit 6 which performs the compression steps described in the previous figures to generate compressed data; and

[0093] A processor unit 7 configured to decompress the compressed data, the processor unit being located in the lighting module 4 .

[0094] The control unit 6 and the processor unit 7 both include a buffer for storing a previous image so as to restore a subsequent image using the previous image.

Claims

1. A method for managing image data in an automotive lighting device (10), the method comprising the following steps: - providing a first image pattern (1), comprising a plurality of pixels (11), wherein each pixel is characterized by a value related to the luminous intensity of the pixel (11); - sending the first image pattern to the light emitting module; - providing a second image pattern (2), said second image pattern comprising a plurality of pixels (21), wherein each pixel is characterized by a value related to the luminous intensity of said pixel (21); - generating a difference pattern (20), the difference pattern being obtained by subtracting the second image pattern from the first image pattern; - normalizing the difference pattern by adding a compensation value to at least some pixels of the difference pattern such that a lower value of the normalized difference pattern is equal to or greater than zero; - sending the compensation value to the lighting module; and - sending the difference pattern (20) to the lighting module (4), so that the lighting module (4) can recover the difference pattern by subtracting the compensation value from the normalized difference value and reconstruct the second image pattern (2) based on the data of the first image pattern (1) and the difference pattern (20).

2. The method according to claim 1, wherein The light pixels (11) of the image pattern (1) are grayscale pixels, and more specifically, the luminous intensity of each pixel (11) is represented by a number, which is a scale from 0 to 255. 3 . The method according to claim 1 , further comprising the step of buffering the first image in the lighting module.

4. The method according to any one of claims 1 to 3, further comprising the steps of: - applying an absolute value function ABS to the difference pattern, thereby generating a modified difference pattern; - sending the modified difference pattern to the light emitting module; as well as - applying said absolute value function ABS to said second image pattern after reconstructing said second image pattern from said first image pattern and said modified difference pattern.

5. The method according to any one of claims 1 to 3, further comprising the steps of: - before sending the difference pattern to the lighting module, compressing at least a portion of the difference pattern, thereby creating compressed data; as well as - decompressing the compressed data by the lighting module.

6. The method according to claim 5, wherein: The step of compressing at least a portion of the difference pattern affects less than 20% of the area of ​​the difference pattern.

7. An automotive lighting device (10), comprising: - a lighting module (4), comprising a plurality of light sources (5); as well as - A control unit (6) for performing the steps of the method according to any of the preceding claims.

8. The automotive lighting device (10) according to claim 7, wherein: The lighting module (4) further comprises a processor unit (7) configured to decompress the compressed data.

9. The automotive lighting device (10) according to claim 8, wherein The control unit (6) and the processor unit (7) both comprise an image buffer for storing the first image.

10. The automotive lighting device (10) according to claim 7, wherein The light source (5) is a solid-state light source.

11. The automotive lighting device (10) according to claim 10, wherein: The light source (5) is an LED.

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