CN116312420A - Method and system for RGB-based adaptive panning head-up display screen - Google Patents

Abstract

The invention provides a method and a system for self-adaptive translation flat-display picture based on RGB. By writing the deviation of the horizontal and pitching into the memory and combining the layout characteristics of the head-up display picture, the self-adaptive compensation of the processing and assembly errors of the head-up display part is realized and the accuracy of the translation process is monitored under the condition that the operation amount and the time delay are not increased based on the position of the starting point of the adjustment distortion correction of the FPGA. The invention can be applied to the compensation of the processing assembly error of the large-view-field digital head-up display, increases the processing and assembly redundancy of the head-up display parts and further reduces the cost.

Description

Method and system for RGB-based adaptive panning head-up display screen

technical field

The invention belongs to the field of large-field digital head-up display screen processing, and in particular relates to a method and system for adaptively shifting head-up display screens based on RGB.

Background technique

The large field of view digital head-up display includes electronic components and optical components. The electronic components are used to generate the symbol picture of the head-up display. The optical component collimates and displays the symbol picture of the electronic component in front of the user. In order to ensure the display accuracy of the head-up display, especially for the aiming display type head-up display, the center of the symbol picture generated by the electronic part of the head-up display should coincide with the center of the optical part. The traditional method is to strictly control the machining accuracy and assembly accuracy of the HUD parts. With the increase of the HUD application field and delivery volume, the traditional method can no longer be satisfied.

Contents of the invention

In order to overcome the deficiencies of the prior art, the present invention provides a method and system for adaptively panning head-up display images based on RGB. By writing the horizontal and pitch deviations into the memory, combined with the layout characteristics of the head-up display screen, the position of the starting point of the distortion correction is adjusted based on the FPGA, and the processing and assembly of the head-up display parts are realized without increasing the amount of calculation and delay. The self-adaptive compensation of errors can increase the processing and assembly margin of HUD parts and further reduce the cost.

A kind of method based on RGB adaptive translation head-up display picture, it is characterized in that the steps are as follows:

Step 1: Input and store the translation parameters. Each set of translation parameters includes the offset △x in the azimuth direction, the offset △y in the pitch direction and the check value. The highest bit of △x and △y represents the direction of translation. The test value is the lower 8 bits after the addition of △x and △y;

Step 2: Start to read the translation parameters from the first group, and judge whether the verification value is correct. If it is correct, judge the translation direction according to the highest bit of △x and △y, and perform the translation correction of the screen, specifically:

a) If the highest bits of △x and △y are both equal to 1, it means that they are both positive, and the translation calculation is performed according to the following formula:

Among them, f(x _c , y _c ) represents the gray value of the corresponding pixel in the screen whose number of rows is x _c and column number is y _c after translation, δ _x represents the interpolation weight in the X direction, 0≤δ _x ≤1 , δ _y represents the interpolation weight in the Y direction, 0≤δ _y ≤1, (x, y) represents the coordinates of the pixel point (x _c , y _c ) corresponding to the input image before translation; |△x| represents △x removal The value after the highest bit, |△y| means the value of △y after removing the highest bit; the positive direction refers to the same direction as the video scanning direction, and the negative direction refers to the opposite direction to the video scanning direction;

b) If the highest bits of △x and △y are both equal to 0, it means that they are both negative, and the translation calculation is performed according to the following formula:

c) If the highest bit of △x is equal to 1 and the highest bit of △y is equal to 0, it means that △x is positive and △y is negative, and the translation calculation is performed according to the following formula:

d) If the highest bit of △x is equal to 0 and the highest bit of △y is equal to 1, it means that △x is negative and △y is positive, and the translation calculation is performed according to the following formula:

If the verification values of the two sets of translation parameters are all wrong, the translation parameter error will be reported, and the screen translation will not be performed;

Step 3: Assign the blue channel of the center point of the input screen to 255, and assign the other pixels to 0, and use the method in step 2 to perform translation calculation, where the values of δ _x and δ _y are set to 1, and then, detect the translation calculation If the coordinate of the pixel point whose blue channel value is 255 is equal to the offset (△x,△y) between its coordinate and the stored center point coordinate, it is considered that the translation result is calculated correctly, otherwise, execute the next frame input screen This step; if the translation results calculated by the method of this step are all incorrect for 6 consecutive frames of input images, report a translation parameter error.

The present invention also provides a RGB-based adaptive translation head-up display system, which is characterized in that it includes: RS422 signal isolation acquisition circuit, single-chip microcomputer minimum system, memory, FPGA minimum system 1, FPGA minimum system 2, image source display unit and adjustment The testing equipment; among them, the debugging equipment is used to input the translation parameters and A818 video during the installation test. After the translation parameters are input through the RS422 signal isolation acquisition circuit, the single-chip microcomputer stores them in the memory, and the single-chip microcomputer reads the translation parameters in the memory and sends them For FPGA minimum system 2, FPGA minimum system 1 converts the input A818 video into DVI format and sends it to FPGA minimum system 2, FPGA minimum system 2 performs screen translation correction according to the translation parameters, and converts the image after translation correction to RGB format for output Display the image source.

The beneficial effects of the present invention are: because the method of directly embedding the translation algorithm into the distortion correction process is adopted, the delay is reduced and hardware resources are saved at the same time; since the translation correctness verification process is performed at the same time as the translation, the accuracy of the translation can be guaranteed. correctness. The invention can realize the adaptive translation correction of the head-up display screen without increasing the amount of calculation and delay, can increase the processing and assembly margin of the head-up display parts, and further reduce the cost.

Description of drawings

Fig. 1 is a kind of RGB-based self-adaptive pan HUD picture system composition schematic diagram of the present invention;

Figure 2 is a schematic diagram of the RS422 signal isolation acquisition circuit.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and embodiments, and the present invention includes but not limited to the following embodiments.

The present invention provides a method and system for RGB-based self-adaptive panning head-up display screen, wherein, the system composition is as shown in Figure 1, including: RS422 signal isolation acquisition circuit, single-chip microcomputer minimum system, memory, FPGA minimum system 1, FPGA Minimum system 2, image source display unit and commissioning equipment.

The commissioning equipment is used to input translation parameters and ARINC818 video during installation and test. After the translation parameters are input through the RS422 signal isolation acquisition circuit, the single-chip microcomputer stores them in the memory, and the single-chip microcomputer reads the translation parameters in the memory and sends them to the FPGA minimum system 2 , FPGA minimum system 1 converts the input ARINC818 video into DVI format and sends it to FPGA minimum system 2. FPGA minimum system 2 performs screen translation correction according to the translation parameters, and converts the translation-corrected picture into RGB format and outputs it to the image source for display .

Among them, the specific implementation of the RS422 signal isolation acquisition circuit is shown in Figure 2, including TVS tubes (V1-V6), resistors (R1-R4), capacitors (C1-C4) and common-mode inductors (L1-L2), which can Effectively avoid damage to the circuit caused by abnormal electrical stress such as lightning strikes. The RS422 communication protocol is used with the commissioning equipment (TX in the figure is sending, RX is receiving, including sending positive and sending negative, receiving positive and receiving negative respectively). In specific implementation, the TVS tube can be SMCJ5.0CA manufactured by Littelfuse, the resistance value of the resistor is 10Ω, and the capacitance of the capacitor is 100pf.

The concrete process of the method for the adaptive translation head-up display screen based on RGB is as follows:

Step 1: Input and store the translation parameters. Each set of translation parameters includes the offset △x in the azimuth direction, the offset △y in the pitch direction and the check value. The highest bit of △x and △y represents the direction of translation. The check value is the lower 8 bits after the addition of △x and △y.

Step 2: The MCU reads the translation parameters in the memory, starting from the first group, and judges whether the verification value is correct. The verification method is to verify the first group of parameters according to the same verification method as the storage method. If read The parameter verification value obtained is consistent with the calculated verification value, and the first set of parameters is used for translation. If the read parameter check value is inconsistent with the calculated check value, and the read second set of parameter check values is consistent with the calculated check value, the second set of parameters is used for translation. If the two sets of verification values are inconsistent, the translation parameter error will be reported through the RS422 signal isolation acquisition circuit, and the screen translation will not be performed.

The translation correction process is to judge the translation direction according to the highest bits of △x and △y, and perform translation correction. The present invention embeds the translation algorithm into the distortion correction process. After the FPGA minimum system 2 receives the translation parameters, according to △x and △y The highest bit judges the direction of translation and performs translation correction calculation. Specifically:

a) If the highest bits of △x and △y are both equal to 1, it means that they are both positive, and the translation calculation is performed according to the following formula:

Among them, f(x _c , y _c ) represents the gray value of the corresponding pixel in the screen whose number of rows is x _c and column number is y _c after translation, δ _x represents the interpolation weight in the X direction, 0≤δ _x ≤1 , δ _y represents the interpolation weight in the Y direction, 0≤δ _y ≤1, (x, y) represents the coordinates of the pixel point (x _c , y _c ) corresponding to the input image before translation, which is determined by the specific product optical system; | △x| indicates the value of △x after removing the highest bit, |△y| indicates the value of △y after removing the highest bit; the positive direction refers to the same direction as the video scanning direction, and the negative direction refers to the opposite direction to the video scanning direction;

b) If the highest bits of △x and △y are both equal to 0, it means that they are both negative, and the translation calculation is performed according to the following formula:

c) If the highest bit of △x is equal to 1 and the highest bit of △y is equal to 0, it means that △x is positive and △y is negative, and the translation calculation is performed according to the following formula:

d) If the highest bit of △x is equal to 0 and the highest bit of △y is equal to 1, it means that △x is negative and △y is positive, and the translation calculation is performed according to the following formula:

Step 3: In order to ensure the correctness of the translation process, the present invention implements a monitoring method for the correctness of the translation process. Currently, the ARINC818 format is commonly used to transmit video signals between on-board devices. After receiving the ARINC818 video, the head-up display needs to convert the video format. After the FPGA minimum system 1 is converted to DVI format, it is input to the FPGA minimum system 2. At the same time, the airborne head-up display is commonly used Both are monochrome HUDs, only displaying the green (G) channel in DVI video.

Translation monitoring method of the present invention is FPGA minimum system 1 when video format conversion, the blue channel assignment value of input picture center point is 255, other point gray value assignment value is 0, adopts the method for step 2 to carry out translation calculation, wherein The values of δ _x and δ _y are set to 1, and then, the coordinates of the pixel point whose blue channel value is 255 after the detection translation calculation is set to (x _B , y _B ), if (x _B , y _B ) and the stored center Point coordinates (x _c , y _c ) satisfy x _B -x _c =△x, y _B -y _c =△y, then it is determined that the calculation of the translation result is correct; otherwise, execute this step for the next frame input screen; if 6 consecutive If none of the translation results calculated by the method in this step are correct for the frame input screen, a translation parameter error will be reported.

Claims (2)

1. A method for adaptively translating a head-up display picture based on RGB is characterized by comprising the following steps:

step 1: inputting translation parameters and storing, wherein each group of translation parameters comprises an offset delta x of the azimuth direction, an offset delta y of the pitching direction and a check value, the highest bit of the delta x and the delta y represents the translation direction, and the check value is the lower 8 bits of the delta x and the delta y after addition;

step 2: reading translation parameters from the first group, judging whether the check value is correct, judging the translation direction according to the highest bit of Deltax and Deltay if the check value is correct, and carrying out translation correction on the picture, wherein the method specifically comprises the following steps:

a) If the most significant bits of Δx and Δy are both equal to 1, the description is forward, and the translation calculation is performed according to the following formula:

wherein f (x) _c ,y _c ) Representing the corresponding line number x in the translated picture _c The column number is y _c Gray value, delta, of pixel point of (2) _x Represents the interpolation weight in the X direction, and delta is not less than 0 _x ≤1，δ _y Represents the interpolation weight in the Y direction, and delta is more than or equal to 0 _y Less than or equal to 1, (x, y) represents pixel point (x) _c ,y _c ) Corresponding coordinates in the input image before translation; the term "Δx" means a value obtained by removing the most significant bit from Δx, and the term "Δy" means a value obtained by removing the most significant bit from Δy; the positive direction is the same as the video scanning direction, and the negative direction is opposite to the video scanning direction;

b) If the most significant bits of Δx and Δy are equal to 0, both are negative, the translation calculation is performed as follows:

c) If the most significant bit of Deltax is equal to 1 and the most significant bit of Deltay is equal to 0, it is stated that Deltax is positive and Deltay is negative, the translation calculation is performed according to the following formula:

d) If the most significant bit of Deltax is equal to 0 and the most significant bit of Deltay is equal to 1, the translation calculation is performed as follows, indicating Deltax is negative and Deltay is positive:

if the check values of the two groups of translation parameters are wrong, reporting the error of the translation parameters, and not translating the picture;

step 3: assigning 255 to the blue channel of the center point of the input picture, assigning 0 to the other pixel points, and performing translation calculation by adopting the method of the step 2, wherein the blue channel is equal to the 0Delta in (d) _x And delta _y Setting the value of (2) to 1, then detecting the pixel point coordinate with the blue channel value of 255 after translation calculation, if the difference between the coordinate and the stored center point coordinate is equal to the offset (delta x, delta y), determining that the translation result calculation is correct, otherwise, executing the step on the next frame input picture; if the translation results obtained by adopting the method in the step of calculating the continuous 6 frames of input pictures are incorrect, reporting the translation parameter errors.

2. An RGB-based adaptive translational head-up display system as set forth in claim 1, comprising: the system comprises an RS422 signal isolation acquisition circuit, a singlechip minimum system, a memory, an FPGA minimum system 1, an FPGA minimum system 2, an image source display unit and a modulation and measurement device; the debugging equipment is used for inputting translation parameters and A818 videos during debugging and testing, the translation parameters are input through the RS422 signal isolation acquisition circuit and then stored in the memory by the singlechip, the singlechip reads the translation parameters in the memory and then sends the translation parameters to the FPGA minimum system 2, the FPGA minimum system 1 converts the input A818 videos into DVI format and then sends the DVI format to the FPGA minimum system 2, the FPGA minimum system 2 carries out picture translation correction according to the translation parameters, and the pictures after translation correction are converted into RGB format and output to the image source for display.

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