Control systems and electronics

Abstract

A control system and an electronic device. The control system includes: an image processing circuit; a first error detection circuit that performs a first error detection on second image data; a first error code value generation circuit that generates a first error code value based on the second image data; a transmission interface circuit; a reception interface circuit; a second error code value generation circuit that generates a second error code value based on the second image data; a second error detection circuit that performs a second error detection based on the first error code value and the second error code value; and a control circuit that outputs a control signal when an error is detected in at least one of the first error detection or the second error detection.

Description

Technical Field

[0001] The present invention relates to a control system, an electronic device and the like. Background Art

[0002] Patent document 1 discloses a head-up display device that displays an image on a display area that can be seen from a driver's seat of a vehicle through a windshield. The head-up display device includes: a vehicle information acquisition unit that acquires vehicle information detected by a vehicle; a control circuit that controls the display of an image; and an image display device that generates an image. The control circuit acquires device information, which is information used when determining device abnormality, and determines whether there is a device abnormality based on the acquired device information. When it is determined that there is a device abnormality, a display content change process is performed to change the display content of the image.

[0003] Patent Document 1: International Publication No. 2019 / 058645

[0004] In a control system of a display device, a plurality of circuit devices are connected in series through communication, and the plurality of circuit devices sequentially perform image processing or display control, etc. In this case, even if an abnormality detection of image data is performed in a certain circuit device and it is confirmed that the image data is not abnormal, an error in image data may occur in the subsequent circuit device or in communication. There is a problem that when such an error occurs, although the result of abnormality detection is not compensated until the final display stage, it is impossible to take corresponding measures for abnormality detection.

[0005] In the above-mentioned Patent Document 1, when the control circuit determines that there is a device abnormality based on the device information obtained from each device of the vehicle, the display content of the image is changed. However, the abnormality detection of the changed image data is not disclosed. In addition, there is no mention of any situation in which an error in the image data occurs in the circuit device of the subsequent stage or in the communication. Summary of the invention

[0006] One embodiment of the present invention relates to a control system that controls a head-up display, comprising: an image processing circuit that maps input first image data into second image data for projection onto a projection surface of the head-up display; a first error detection circuit that performs a first error detection on the second image data; a first error code value generation circuit that generates a first error code value based on the second image data; a transmission interface circuit that transmits the second image data; a receiving interface circuit that receives the second image data sent by the transmission interface circuit; a second error code value generation circuit that generates a second error code value based on the second image data received by the receiving interface circuit; a second error detection circuit that performs a second error detection on the second image data received by the receiving interface circuit based on the first error code value and the second error code value; and a control circuit that outputs a control signal that shuts off projection of light onto the projection surface when an error is detected in at least one of the first error detection or the second error detection.

[0007] Furthermore, another aspect of the present invention relates to an electronic device including the above-mentioned control system and the above-mentioned head-up display. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 This is an example of a display on a head-up display.

[0009] Figure 2 This is a structural example of an electronic device.

[0010] Figure 3 This is the first structural example of the control system.

[0011] Figure 4 It is the process flow chart of the control system.

[0012] Figure 5 This is a modified structural example of a head-up display.

[0013] Figure 6 This is the second configuration example of the control system.

[0014] Figure 7 This is the third configuration example of the control system.

[0015] Figure 8 This is a configuration example of an image processing device in the case of performing the first error detection using the inverse mapping process.

[0016] Fig. 9 This is an example of the configuration of an image processing device and a processing device in the case where the image processing device detects a processing error in distortion correction.

[0017] Fig.10 This is a detailed configuration example of the image processing circuit and the third error detection circuit.

[0018] Description of symbols

[0019] 10 screen; 20, 30 AR display; 50 front vehicle; 100 image processing device; 110 receiving interface circuit; 115 image processing circuit; 120 storage circuit; 130 image conversion circuit; 140 sending interface circuit; 150 third error detection circuit; 151 operation circuit; 152 comparison circuit; 160 coordinate address conversion circuit; 170 first error detection circuit; 171 inverse conversion circuit; 172 comparison circuit; 180 first error code value generation circuit; 190 shielding circuit; 200 display controller; 210 receiving interface circuit; 220 timing generation circuit; 240 sending interface Circuit; 280 second error code value generating circuit; 290 shielding circuit; 300 processing device; 310 control circuit; 370 second error detection circuit; 400 control system; 500 head-up display; 510 display driver; 520 backlight controller; 530 light source; 540 display panel; 550 optical system; 600 electronic device; CD1 first error code value; CD2 second error code value; CNT control signal; ER1 first error detection signal; ER2 second error detection signal; IMA first image data; IMB second image data; IMC third image data; RCRD reference coordinates. DETAILED DESCRIPTION

[0020] Hereinafter, preferred embodiments of the present invention will be described in detail. In addition, the present embodiments described below do not unduly limit the contents described in the claims, and all the structures described in the present embodiments are not necessarily essential structural elements.

[0021] 1. Reduced visibility of the head-up display due to image abnormalities

[0022] Figure 1 This is an example of a head-up display. Hereinafter, the head-up display is also omitted and recorded as HUD. Here, the case where the HUD is installed in a mobile body such as a car, an airplane, or a ship and displays information to the user riding on the mobile body is described as an example. In addition, the use of HUD is not limited to mobile bodies, as long as it is used to display information in an overlapping manner in the user's field of vision.

[0023] like Figure 1 As shown in the upper part, the user riding on the moving object sees the outside scenery through the windshield. Hereinafter, this is referred to as the background. The HUD screen 10 is set in the background, and in the screen 10, except for the information display part, everything is visible through the background. Figure 1 In the example of FIG. 5 , the AR display 20 following the preceding vehicle 50 is an information presentation portion, and portions other than the AR display 20 are transparent to the background. Thus, the user can view the background together with the information displayed on the HUD.

[0024] Typically, the AR display 20 occupies a relatively low proportion of the screen 10, so that the user can see the background of the screen 10 through the HUD. In addition, the display position of the AR display 20 is controlled to follow the preceding vehicle 50, so that typically, the AR display 20 does not overlap the preceding vehicle 50. However, if Figure 1 As shown in the lower part, if an abnormality occurs in image processing, the display of the abnormality may reduce the visibility of the background. Figure 1 The lower part shows an example in which the AR display 30 abnormally enlarged and displayed covers the preceding vehicle 50 and the user cannot see the preceding vehicle 50. In addition, the abnormal state that reduces visibility is not limited to Figure 1 The lower portion may be a state where a relatively large area within the screen 10 is displayed to cover the background, or a state where a high-brightness image is displayed within the screen 10 so that the background is difficult to see.

[0025] 2. Electronic equipment and control systems

[0026] Figure 2 This is a configuration example of the electronic device 600 in this embodiment. The electronic device 600 is a HUD system, and includes a control system 400 and a head-up display 500 .

[0027] The control system 400 is a system that controls the head-up display 500 , and specifically, performs display control of the head-up display 500 by sending image data IMB and a timing control signal to the head-up display 500 .

[0028] The head-up display 500 projects an image onto a projection surface according to the image data IMB and the timing control signal, so that a virtual image is displayed in the field of vision of a user viewing the projection surface. The projection surface is a windshield of a mobile body equipped with a HUD system or a screen provided exclusively for the HUD system. The head-up display 500 includes a display driver 510, a backlight controller 520, a light source 530, a display panel 540, and an optical system 550.

[0029] The display driver 510 drives the display panel 540 according to the image data IMB and the timing control signal from the control system 400, so that the display panel 540 displays an image. Figure 2 In the example of , the display panel 540 is a liquid crystal display panel. The backlight controller 520 controls the on / off of the light source 530 and the amount of emitted light. The light source 530 emits light to the display panel 540. The optical system 550 projects the light that has passed through the display panel 540 onto the projection surface. As a result, the image displayed on the display panel 540 is projected onto the projection surface.

[0030] In addition, the head-up display 500 is not limited to Figure 2. For example, the display panel 540 may also be a panel using self-luminous elements such as OLED. OLED is the abbreviation of Organic Light Emitting Diode. In this case, the light source 530 and the backlight controller 520 are omitted, and the optical system 550 projects the light emitted by the display panel 540 onto the projection surface. Alternatively, the display driver 510 may also be included in the control system 400. In this case, the display driver 510 and the display controller 200 described later may also be composed of an integrated integrated circuit device.

[0031] Figure 3 This is a first structural example of the control system 400 in this embodiment. The control system 400 includes an image processing device 100, a display controller 200, and a processing device 300. The image processing device 100, the display controller 200, and the processing device 300 are each composed of, for example, an integrated circuit device in which a plurality of circuit elements are integrated on a semiconductor substrate. In addition, as described above, the display controller 200 may also include the function of a display driver 510.

[0032] The image processing device 100 performs distortion correction on the first image data IMA and outputs the second image data IMB after the distortion correction. Distortion correction is correction to cancel or reduce the distortion of the image caused by the distortion of the projection surface of the head-up display or the distortion of the image caused by the optical system. The image processing device 100 includes a receiving interface circuit 110, an image processing circuit 115, a transmitting interface circuit 140, a first error detection circuit 170 and a first error code value generation circuit 180.

[0033] The receiving interface circuit 110 receives the first image data IMA from an external device such as the processing device 300. The receiving interface circuit 110 may also be a receiving circuit of various communication interfaces, such as LVDS, DVI, DisplayPort, GMSL, or GVIF. LVDS is the abbreviation of Low Voltage Differential Signaling, DVI is the abbreviation of Digital Visual Interface, GMSL is the abbreviation of Gigabit Multimedia Serial Link, and GVIF is the abbreviation of Gigabit Video InterFace.

[0034] The image processing circuit 115 maps the first image data IMA into the second image data IMB for projection onto the projection surface of the head-up display 500. This mapping process is equivalent to the above-mentioned distortion correction. In addition, the mapping process is also called a distortion process. The image processing circuit 115 can also be either a reverse distortion engine or a forward distortion engine. Reverse distortion is a distortion process in which the pixel position on the second image data IMB is moved to a reference coordinate corresponding to the pixel position, and the pixel data of the second image data IMB is obtained based on the pixel data of the first image data IMA at the reference coordinate. Forward distortion is a distortion process in which the pixel data of each pixel of the first image data IMA is moved to the movement destination coordinate corresponding to each pixel data to obtain the pixel data of the second image data IMB at the movement destination coordinate.

[0035] The transmission interface circuit 140 transmits the second image data IMB to the display controller 200. The transmission interface circuit 140 may be a transmission circuit of various communication interfaces, and as an example, is a transmission circuit of LVDS, DVI, DisplayPort, GMSL, or GVIF.

[0036] The first error detection circuit 170 performs a first error detection on the second image data IMB output by the image processing circuit 115, and outputs a first error detection signal ER1 as a result. In the first structural example, the first error detection is a glare error detection. Specifically, the first error detection circuit 170 obtains an index value indicating the glare of the head-up display, that is, a glare index value, based on the second image data IMB. The first error detection circuit 170 compares the glare index value with a threshold value, and when the glare index value is greater than the threshold value, it is determined that a glare error has occurred.

[0037] The glare index value is an index value indicating the glare of the head-up display. Specifically, the glare index value indicates the degree to which the visibility of the background is reduced by the image when the image based on the second image data IMB is displayed on the head-up display. Figure 1 As described above, the image displayed on the head-up display may block the background, or the background may be difficult to see due to glare from the image displayed on the head-up display. The value indicating the extent of these is the glare index value.

[0038] The first error detection circuit 170 obtains the glare index value by integrating the pixel values ​​included in the second image data IMB of one screen, that is, one display frame. Specifically, when the glare index value is B, B is B=C1×Rsum+C2×Gsum+C3×Bsum. Here, Rsum is the integrated value of the red pixel value, Gsum is the integrated value of the green pixel value, Bsum is the integrated value of the blue pixel value, and C1, C2, and C3 are coefficients. The coefficients C1, C2, and C3 are coefficients when converting the pixel value of RGB to the brightness value Y of YCrCb, and appropriate coefficients are set according to the color space used by the image data. However, the coefficients C1, C2, and C3 are not limited to this, and may be any real number greater than 0. In addition, the first error detection circuit 170 may calculate the brightness value Y in units of one pixel and integrate Y to calculate the glare index value B. In this case, Y=C1×Rpx+C2×Gpx+C3×Bpx, and B=Ysum. Rpx, Gpx, Bpx are the red pixel value, green pixel value, and blue pixel value of one pixel. Ysum is the cumulative value of the brightness value Y.

[0039] The first error code value generating circuit 180 generates a first error code value CD1 based on the second image data IMB output by the image processing circuit 115. For example, in each frame, the first error code value generating circuit 180 generates the first error code value CD1 based on the second image data IMB of the frame. When no error is detected in the first error detection, the first error detection is used to ensure that the second image data IMB is image data without abnormalities. That is, the first error code value CD1 is an error code value generated based on the second image data IMB that is guaranteed to be free of abnormalities. The first error code value CD1 is, for example, a CRC code. CRC is the abbreviation of Cyclic Redundancy Check. Alternatively, the first error code value CD1 may also be a checksum, a Hamming code, or an ECC code. ECC is the abbreviation of Error Correcting Code.

[0040] The display controller 200 performs display control of the head-up display 500. Specifically, the display controller 200 generates a timing control signal and transmits the timing control signal together with the received second image data IMB to the head-up display 500. The display controller 200 includes a reception interface circuit 210, a timing generation circuit 220, a transmission interface circuit 240, and a second error code value generation circuit 280.

[0041] The reception interface circuit 210 receives the second image data IMB from the image processing device 100. The reception interface circuit 210 may be a reception circuit of various communication interfaces, and as an example, is a reception circuit of LVDS, DVI, DisplayPort, GMSL, or GVIF.

[0042] The timing generation circuit 220 generates a timing control signal for controlling the display timing of the head-up display 500. The timing control signal is, for example, a vertical synchronization signal, a horizontal synchronization signal, a dot clock signal, and a data enable signal.

[0043] The transmission interface circuit 240 transmits the second image data IMB and the timing control signal to the display driver 510 of the head-up display 500. The transmission interface circuit 240 may be a transmission circuit of various communication interfaces, such as LVDS, DVI, DisplayPort, GMSL, or GVIF.

[0044] The second error code value generating circuit 280 generates a second error code value CD2 based on the second image data IMB received by the receiving interface circuit 210. For example, in each frame, the second error code value generating circuit 280 generates the second error code value CD2 based on the second image data IMB of the frame. The second error code value generating circuit 280 calculates the second error code value CD2 by the same calculation method as the calculation method used by the first error code value generating circuit 180 to calculate the first error code value CD1. For example, when the first error code value CD1 is a CRC code, the second error code value CD2 is also a CRC code obtained by the same CRC calculation. Alternatively, when the first error code value CD1 is a checksum, a Hamming code, or an ECC code, the second error code value CD2 is also a checksum, a Hamming code, or an ECC code.

[0045] The processing device 300 is a processor that performs system control of the electronic device 600. The processor is a microcomputer or a CPU, etc. CPU is the abbreviation of Central Processing Unit. Alternatively, the processing device 300 may also be an FPGA or an ASIC, etc. FPGA is the abbreviation of Field-Programmable Gate Array. ASIC is the abbreviation of Application Specific Integrated Circuit. The processing device 300 includes a second error detection circuit 370 and a control circuit 310.

[0046] The second error detection circuit 370 detects a communication error between the image processing device 100 and the display controller 200 through the second error detection, and outputs a second error detection signal ER2 as a result. Specifically, the second error detection circuit 370 compares the first error code value CD1 with the second error code value CD2. When the first error code value CD1 and the second error code value CD2 are inconsistent, the second error detection circuit 370 outputs the second error detection signal ER2 indicating an error, and when the first error code value CD1 and the second error code value CD2 are consistent, the second error detection circuit 370 outputs the second error detection signal ER2 indicating no error.

[0047] The control circuit 310 outputs a control signal CNT based on the first error detection signal ER1 and the second error detection signal ER2. Specifically, when the control circuit 310 detects an error in the first error detection, the second error detection, or both, it outputs a control signal CNT that turns off the projection of light onto the projection surface of the HUD. In the first structural example, when the control circuit 310 detects the above-mentioned error, it outputs a control signal CNT that turns off the light source 530 to the backlight controller 520. When the control signal CNT that turns off the light source 530 is input, the backlight controller 520 turns off the light source 530. As a result, the light is not projected onto the projection surface, and the user can see the background through the projection surface.

[0048] Figure 4 4 is a flowchart of the process of the control system 400. In step S1, the image processing circuit 115 performs distortion correction on the first image data IMA by performing a mapping process.

[0049] In step S2, the first error detection circuit 170 performs a visibility check on the distortion-corrected second image data IMB by performing a glare error detection. As described above, the visibility check is to check whether the visibility of the background is good or not through the head-up display when the image based on the second image data IMB is displayed. In step S3, the control circuit 310 performs processing corresponding to the result of the visibility check. In the case where the visibility check is an error, in step S4, the control circuit 310 outputs a control signal CNT to turn off the light source 530. In the case where there is no problem in the visibility check, the process proceeds to step S5.

[0050] In step S5, the first error code value generation circuit 180 calculates the CRC code based on the second image data IMB output by the image processing circuit 115. In step S6, the transmission interface circuit 140 transmits the second image data IMB, and the reception interface circuit 210 receives the second image data IMB. In step S7, the second error code value generation circuit 280 calculates the CRC code based on the second image data IMB received by the reception interface circuit 210.

[0051] In step S8, the second error detection circuit 370 compares the two CRC codes. In step S9, the control circuit 310 determines whether the two CRC codes are consistent. This determination is equivalent to the visibility confirmation in the display controller 200. That is, it means that when the two CRC codes are consistent, the same image data as the second image data IMB with no problem in the visibility confirmation in the image processing circuit 115 is input to the display controller 200, and it means that in the display controller 200, there is no problem with the visibility of the second image data IMB.

[0052] In step S9 , if the CRC codes match, the control circuit 310 ends the process, and if the CRC codes do not match, in step S4 , the control circuit 310 outputs the control signal CNT to turn off the light source 530 .

[0053] In addition, Figure 2 In the example in which the display panel 540 is a liquid crystal display panel and the control circuit 310 outputs the control signal CNT to turn off the light source 530, the structure for turning off the projection of light onto the projection surface is not limited to this. As for "turning off the projection of light onto the projection surface", any method may be used as long as the light is not projected onto the projection surface in the end.

[0054] For example, Figure 5 FIG. 5 shows a modified example of the structure of the head-up display 500. Figure 5 In the embodiment, the control circuit 310 outputs a control signal CNT that turns off the display driver 510 driving the display panel 540. When the display driver 510 receives the control signal CNT, it stops displaying an image based on the second image data IMB and sets the display panel 540 to a non-transmitting state. As a result, light is not projected onto the projection surface.

[0055] Alternatively, the display panel 540 may be a panel using self-luminous elements. In this case, the control circuit 310 outputs a control signal CNT that turns off the light emission of all pixels of the display panel 540. When the control signal CNT is input, the display panel 540 stops displaying an image based on the second image data IMB and sets all pixels to a non-luminous state. As a result, light is not projected onto the projection surface.

[0056] or, Figure 6 A second configuration example of the control system 400 is shown. Figure 6 In the image processing device 100, the second error detection circuit 370, the control circuit 310 and the masking circuit 190 are included. When at least one of the first error detection circuit 170 and the second error detection circuit 370 detects an error, the control circuit 310 outputs a control signal CNT for masking the second image data IMB. When the control signal CNT is input, the masking circuit 190 masks the second image data IMB input to the transmission interface circuit 140. At this time, the masking circuit 190, for example, stops the output of the image data, or outputs image data in which the entire screen is displayed in black to the transmission interface circuit 140. As a result, the light is not projected onto the projection surface. When neither the first error detection circuit 170 nor the second error detection circuit 370 detects an error, the masking circuit 190 directly outputs the second image data IMB to the transmission interface circuit 140.

[0057] or, Figure 7A third configuration example of the control system 400 is shown. Figure 7 In the embodiment, the display controller 200 includes a second error detection circuit 370, a control circuit 310, and a mask circuit 290. When at least one of the first error detection circuit 170 and the second error detection circuit 370 detects an error, the control circuit 310 outputs a control signal CNT for masking the second image data IMB. When the control signal CNT is input, the mask circuit 290 masks the second image data IMB input to the transmission interface circuit 240. As a result, light is not projected onto the projection surface. When neither the first error detection circuit 170 nor the second error detection circuit 370 detects an error, the mask circuit 290 directly outputs the second image data IMB to the transmission interface circuit 240.

[0058] In the above embodiment, the control system 400 includes: an image processing circuit 115, which maps the input first image data IMA into the second image data IMB for projection onto the projection surface of the head-up display 500; a first error detection circuit 170, which performs a first error detection on the second image data IMB; and a first error code value generation circuit 180, which generates a first error code value CD1 based on the second image data IMB. The control system 400 includes: a transmission interface circuit 140, which transmits the second image data IMB; a receiving interface circuit 210, which receives the second image data IMB transmitted by the transmission interface circuit 140; and a second error code value generation circuit 280, which generates a second error code value CD2 based on the second image data IMB received by the receiving interface circuit 210. The control system 400 includes: a second error detection circuit 370, which performs a second error detection on the second image data IMB received by the receiving interface circuit 210 based on the first error code value CD1 and the second error code value CD2; and a control circuit 310, which outputs a control signal CNT to shut down the projection of light onto the projection surface when an error is detected in at least one of the first error detection or the second error detection.

[0059] According to the present embodiment, the first error detection circuit 170 performs the first error detection on the second image data IMB, and at the subsequent stage, the transmission interface circuit 140 and the reception interface circuit 210 transmit and receive the second image data IMB. At this time, the second error detection circuit 370 performs the second error detection based on the first error code value CD1 generated based on the second image data IMB before transmission and the second error code value CD2 generated based on the second image data IMB after reception. Thus, it can be ensured that the second image data IMB after reception is the same image data as the second image data IMB after the first error detection. For example, when the visibility confirmation of whether the visibility of the background is good when the image is displayed on the head-up display is performed in the first error detection, the visibility can also be guaranteed in the second image data IMB after reception.

[0060] Furthermore, since the projection of light onto the projection surface is turned off when an error is detected in at least one of the first error detection or the second error detection, the image display based on the second image data IMB in which the error occurred is not performed, and the projection surface is not irradiated with light. Thus, the user can see the background through the screen of the head-up display 500.

[0061] in addition, Figure 3 The hardware structure of the control system 400 shown is only an example. The control system 400 can be of any structure as long as it includes the image processing circuit 115, the first error detection circuit 170, the first error code value generating circuit 180, the sending interface circuit 140, the receiving interface circuit 210, the second error code value generating circuit 280, the second error detection circuit 370 and the control circuit 310.

[0062] Furthermore, in the present embodiment, the first error detection circuit 170 obtains a glare index value which is an index value indicating the glare of the head-up display 500 based on the second image data IMB, and performs the first error detection based on the glare index value.

[0063] According to the present embodiment, the first error detection circuit 170 can detect the state in which the visibility of the background is reduced due to the image based on the second image data IMB as a glare error by performing the first error detection based on the glare index value. Thus, when the glare error is not detected in the first error detection and the second error detection, it can be ensured that there is no glare error in the second image data IMB received by the receiving interface circuit 210. In addition, since the projection of light to the projection surface is turned off when an error is detected in at least one of the first error detection and the second error detection, it is not guaranteed that the second image data IMB without a glare error will not be displayed on the head-up display 500.

[0064] In addition, in this embodiment, the control system 400 includes a first circuit device and a second circuit device. The first circuit device includes the image processing circuit 115, the first error detection circuit 170, the first error code value generation circuit 180, and the transmission interface circuit 140. The second circuit device includes the reception interface circuit 210 and the second error code value generation circuit 280.

[0065] According to this embodiment, it is ensured that the second image data IMB received by the second circuit device at the subsequent stage is the same image data as the second image data IMB after the first error detection in the first circuit device at the previous stage. Therefore, even if the first circuit device performs the first error detection and a second circuit device is provided at the subsequent stage, the result of the first error detection can be substantially guaranteed in the second circuit device at the subsequent stage. Furthermore, in any of the previous stage and the subsequent stage, when the state in which there is no error in the second image data IMB cannot be guaranteed, the projection of light onto the projection surface is turned off.

[0066] In addition, Figure 3 In the embodiment, the image processing device 100 is a first circuit device, and the display controller 200 is a second circuit device, but the first circuit device and the second circuit device are not limited thereto. For example, the second circuit device may also be a display driver. In this case, the first circuit device may also be a display controller with a built-in distortion correction function, or the second circuit device may also be a display driver with a built-in display controller function. In addition, the control system 400 may also include a first circuit device as the image processing device 100, a second circuit device as the display controller 200, and a third circuit device as the display driver. In this case, the second image data received by the third circuit device may also be subjected to the same error detection as the second error detection.

[0067] Furthermore, in the present embodiment, the control circuit 310 outputs the control signal CNT for turning off the light source 530 of the head-up display 500 .

[0068] According to the present embodiment, the light source 530 is turned off when an error is detected in at least one of the first error detection and the second error detection, and therefore, an image based on the second image data IMB in which an error has occurred is not displayed.

[0069] In addition, if Figure 6 As described above, the control system 400 may include the mask circuit 190 that performs mask processing on the second image data IMB before being transmitted by the transmission interface circuit 140 based on the control signal CNT.

[0070] According to the present embodiment, when an error is detected in at least one of the first error detection or the second error detection, the second image data IMB before being transmitted by the transmission interface circuit 140 is masked, so that an image based on the erroneous second image data IMB is not displayed.

[0071] In addition, if Figure 7 As described above, the control system 400 may include the mask circuit 290 that performs mask processing on the second image data IMB received by the reception interface circuit 210 based on the control signal CNT.

[0072] According to the present embodiment, when an error is detected in at least one of the first error detection or the second error detection, the second image data IMB received by the reception interface circuit 210 is masked, so that an image based on the erroneous second image data IMB is not displayed.

[0073] 3.1st Error Detection Using Inverse Mapping Process

[0074] exist Figure 3 In the example in which the first error detection is a glare error detection, the first error detection is not limited to this. Figure 8 This is a configuration example of the image processing device 100 in the case of performing the first error detection using the inverse mapping process. Note that the same reference numerals as those of the components already described are used, and the description of the components is appropriately omitted.

[0075] In this configuration example, the first error detection circuit 170 performs error detection on the second image data IMB by comparing the third image data IMC obtained by inverse mapping the second image data IMB with the first image data IMA. The first error detection circuit 170 includes an inverse conversion circuit 171 and a comparison circuit 172 .

[0076] The inverse conversion circuit 171 performs an inverse mapping process on the second image data IMB and outputs the processed third image data IMC. The inverse mapping process is the inverse conversion of the mapping process performed by the image processing circuit 115. That is, when the mapping process in the image processing circuit 115 and the inverse mapping process in the inverse conversion circuit 171 are performed normally, the third image data IMC is the same as the first image data IMA. However, since interpolation processing and the like are performed in the mapping process or the inverse mapping process, the third image data IMC and the first image data IMA may not be completely consistent. Specifically, the third image data IMC and the first image data IMA may be substantially consistent as long as the content of the image represented by the third image data IMC is determined to be the same as the content of the image represented by the first image data IMA.

[0077] The comparison circuit 172 performs a comparison process between the first image data IMA and the third image data IMC, and outputs a first error detection signal ER1 as a result. Specifically, the comparison circuit 172 obtains an index representing the similarity between the first image data IMA and the third image data IMC. The index is a shape index or a visibility index described later. Alternatively, the index may be SSD (Sum of Squared Difference), SAD (Sum of Absolute Difference), or NCC (Normalized Cross Correlation), etc. The comparison circuit 172 performs error detection on the second image data IMB by comparing the index with a threshold value. The threshold value represents the degree of similarity that the first image data IMA and the third image data IMC are allowed to have.

[0078] The first calculation method of the shape index is described. The comparison circuit 172 obtains the inter-image distance between the first image data IMA and the third image data IMC in the color space. The color space is, for example, RGB or YCrCb. Specifically, the comparison circuit 172 obtains the square value of the distance between the pixel of the first image data IMA and the pixel of the third image data IMC corresponding to the pixel in the color space. The comparison circuit 172 accumulates the square value in the image and sets the accumulated value as the inter-image distance. In the first calculation method, the inter-image distance is equivalent to the shape index.

[0079] Next, the second calculation method of the shape index is described. The comparison circuit 172 extracts edges from the first image data IMA and the third image data IMC to obtain respective edge images. The comparison circuit 172 compares the edge image extracted from the first image data IMA with the edge image extracted from the third image data IMC. Specifically, the comparison circuit 172 extracts edges from the first image data IMA and the third image data IMC using a Sobel filter or the like, and obtains a correlation value between the edge image extracted from the first image data IMA and the edge image extracted from the third image data IMC. In the second calculation method, the correlation value of the edge image is equivalent to the shape index.

[0080] Next, the calculation method of the visibility index is described. The "visibility" in the visibility index means the visibility of the display object such as the icon displayed on the head-up display, which is different from the visibility of the above-mentioned background. Here, the color space is set to YCrCb, but the color space can also be RGB, etc. The comparison circuit 172 obtains a histogram based on the Y channel of the first image data IMA. Similarly, the comparison circuit 172 obtains a histogram based on the Cr channel and the Cb channel of the first image data IMA, and obtains a histogram based on the Y channel, the Cr channel, and the Cb channel of the third image data IMC.

[0081] The comparison circuit 172 performs a cross-correlation operation on the histograms of the first image data IMA and the third image data IMC in the Y channel. The cross-correlation operation is an operation in which the two histograms are staggered and delayed to obtain the correlation value, and the correlation value is obtained while the delay is changed. If the delay is changed, the correlation value of the two histograms increases, and a peak value appears in the delay. There may be multiple peak values. Similarly, the comparison circuit 172 performs a cross-correlation operation on the histograms of the first image data IMA and the third image data IMC in the Cr channel and the Cb channel.

[0082] The comparison circuit 172 checks the delay value where the peak appears in the cross-correlation signal of all channels, and finds the maximum delay value among the delay values. The maximum delay value corresponds to the visibility index. Since the maximum delay value increases when the contrast between the color of the display object such as an icon and the color of the background image is high, the visibility index represents the contrast between the color of the display object and the color of the background image. Since the higher the color contrast, the higher the visibility, the larger the visibility index, the higher the similarity.

[0083] In addition, the image processing device 100 may also perform error detection and Figure 3 Both of the dazzling error detection described in etc.

[0084] In the present embodiment described above, the first error detection circuit 170 converts the second image data IMB into the third image data IMC by the inverse mapping process of the mapping process, and compares the first image data IMA with the third image data IMC, thereby performing the first error detection.

[0085] When an abnormality occurs in the mapping process, when an image is displayed on the head-up display through the second image data IMB after the mapping process, the visibility of the background may be reduced. According to the present embodiment, by comparing the first image data IMA with the third image data IMC, it can be determined whether the mapping process from the first image data IMA to the second image data IMB is normal, and the third image data IMC is obtained by inverse mapping the first image data IMA. Therefore, when no error is detected in the first error detection and the second error detection, it can be guaranteed that there is no mapping process error in the second image data IMB received by the receiving interface circuit 210. In addition, when an error is detected in at least one of the first error detection or the second error detection, the projection of light to the projection surface is turned off, so it cannot be guaranteed that the second image data IMB without a mapping process error will not be displayed on the head-up display 500.

[0086] 4.3rd Error Detection

[0087] Fig. 9 This is a configuration example of the image processing device 100 and the processing device 300 when the image processing device 100 detects a processing error in distortion correction. In this configuration example, the image processing device 100 includes a third error detection circuit 150. In addition, the same reference numerals as those of the components already described are given, and the description of the components is appropriately omitted.

[0088] In this configuration example, the image processing device 100 includes a third error detection circuit 150. The image processing circuit 115 outputs a reference coordinate RCRD on the first image data IMA corresponding to a pixel position on the second image data IMB during the mapping process. The third error detection circuit 150 detects a processing error of the distortion correction by detecting an error in the reference coordinate RCRD, and outputs a third error detection signal ER3 as a result.

[0089] The control circuit 310 outputs a control signal CNT based on the first error detection signal ER1, the second error detection signal ER2, and the third error detection signal ER3. Specifically, when an error is detected in the first error detection, the second error detection, the third error detection, or two or more of these error detection processes, the control circuit 310 outputs a control signal CNT for shutting off the projection of light onto the projection surface of the HUD.

[0090] in addition, Fig. 9 The example in which the control circuit 310 is included in the processing device 300 is shown, but the control circuit 310 may also be Figure 6 The image processing device 100 may also be included in the image processing device 100. Figure 7 That is included in the display controller 200.

[0091] Fig.10 1 is a detailed configuration example of the image processing circuit 115 and the third error detection circuit 150. The image processing circuit 115 includes a storage circuit 120, an image conversion circuit 130, and a coordinate address conversion circuit 160. The third error detection circuit 150 includes an operation circuit 151 and a comparison circuit 152.

[0092] The memory circuit 120 stores the first image data IMA. The memory circuit 120 is a line buffer for storing a predetermined number of lines of image data or a frame memory for storing one frame of image data.

[0093] The image conversion circuit 130 performs image conversion based on coordinate conversion on the first image data IMA and outputs the second image data IMB after the image conversion. The image conversion based on coordinate conversion is an image conversion that generates the second image data IMB by moving the pixel data of the first image data IMA to the pixel position on the second image data IMB represented by the coordinate conversion. Specifically, the image conversion circuit 130 generates the second image data IMB by performing distortion correction on the first image data IMA.

[0094] The image conversion circuit 130 corresponds to a reverse warping engine. The meaning of reverse warping is as described above. The image conversion circuit 130 outputs reference coordinates RCRD on the first image data IMA corresponding to the pixel position on the second image data IMB based on the correction parameter WP as a warping parameter.

[0095] The coordinate address conversion circuit 160 converts the reference coordinate RCRD into a read address RADD of the storage circuit 120. The read address RADD is an address where pixel data corresponding to the reference coordinate RCRD is stored.

[0096] The storage circuit 120 reads the pixel data PXDT from the read address RADD and outputs it to the image conversion circuit 130. The image conversion circuit 130 forms the second image data IMB based on the pixel data PXDT. As described later, a plurality of pixel data may be read for one reference coordinate RCRD, and the image conversion circuit 130 may also perform interpolation processing on the plurality of pixel data to obtain the pixel data of the second image data IMB.

[0097] The third error detection circuit 150 includes: an operation circuit 151 that operates an error code value CDQ based on a reference coordinate RCRD; and a comparison circuit 152 that compares the error code value CDQ with an expected value CDEX of the error code value.

[0098] The operation circuit 151 operates an error code value CDQ in each frame according to the reference coordinate RCRD of the frame. The error code value CDQ is, for example, a CRC code. CRC is the abbreviation of Cyclic Redundancy Check. Alternatively, the error code value CDQ may also be a checksum, a Hamming code, or an ECC code. ECC is the abbreviation of Error Correcting Code.

[0099] When the error code value CDQ is inconsistent with the expected value CDEX, the comparison circuit 152 outputs the third error detection signal ER3 indicating an error, and when the error code value CDQ is consistent with the expected value CDEX, the comparison circuit 152 outputs the third error detection signal ER3 indicating no error. The expected value CDEX is associated with the correction parameter WP, and when the correction parameter WP is changed, the expected value CDEX is also changed accordingly. The correction parameter WP and the expected value CDEX are input to the image processing device 100 from an external device such as the processing device 300, for example.

[0100] In addition, the third error detection circuit 150 may perform error detection on the reference coordinate RCRD. Fig.10 In the embodiment, the third error detection circuit 150 detects an error in the reference coordinate RCRD, but the present invention is not limited thereto. The third error detection circuit 150 may also detect an error in the data generated based on the reference coordinate RCRD to perform error detection on the reference coordinate RCRD. For example, the third error detection circuit 150 may also detect an error in the read address RADD output based on the reference coordinate RCRD. In this case, by confirming whether the read address RADD is correct, it is confirmed whether the reference coordinate RCRD is correct.

[0101] In the above embodiment, the control system 400 includes the third error detection circuit 150. The image processing circuit 115 includes: a storage circuit 120 that stores the first image data IMA; and an image conversion circuit 130 that maps the first image data IMA stored in the storage circuit 120 into the second image data IMB. The image conversion circuit 130 outputs a reference coordinate RCRD indicating a pixel position on the first image data IMA, and outputs the second image data IMB based on the pixel data of the reference coordinate RCRD read from the storage circuit 120 based on the output reference coordinate RCRD. The third error detection circuit 150 performs a third error detection on the reference coordinate RCRD output by the image conversion circuit 130. When an error is detected in at least one of the first error detection, the second error detection, or the third error detection, the control circuit 310 outputs a control signal CNT that turns off the projection of light to the projection surface.

[0102] When an abnormality occurs in the coordinate conversion in the mapping process, when the image is displayed on the head-up display through the second image data IMB after the mapping process, the visibility of the background may be reduced. According to the present embodiment, by performing error detection on the reference coordinates RCRD output by the image conversion circuit 130, it can be determined whether the coordinate conversion in the mapping process is normal. Therefore, when no error is detected in the second error detection and the third error detection, it can be guaranteed that there is no coordinate conversion error in the second image data IMB received by the receiving interface circuit 210. In addition, when an error is detected in at least one of the second error detection or the third error detection, the projection of light to the projection surface is turned off, so it cannot be guaranteed that the second image data IMB without a coordinate conversion error will not be displayed on the head-up display 500.

[0103] The control system of the present embodiment described above controls a head-up display. The control system includes: an image processing circuit that maps the input first image data into second image data for projection onto a projection surface of the head-up display; a first error detection circuit that performs a first error detection on the second image data; a first error code value generation circuit that generates a first error code value based on the second image data; and a transmission interface circuit that transmits the second image data. The control system includes: a receiving interface circuit that receives the second image data sent by the transmission interface circuit; a second error code value generation circuit that generates a second error code value based on the second image data received by the receiving interface circuit. The control system includes: a second error detection circuit that performs a second error detection on the second image data received by the receiving interface circuit based on the first error code value and the second error code value; and a control circuit that outputs a control signal that shuts off the projection of light onto the projection surface when an error is detected in at least one of the first error detection or the second error detection.

[0104] According to the present embodiment, the first error detection circuit performs the first error detection on the second image data, and at the subsequent stage, the transmission interface circuit and the reception interface circuit transmit and receive the second image data. At this time, the second error detection circuit performs the second error detection based on the first error code value generated according to the second image data before transmission and the second error code value generated according to the second image data after reception. Thus, it can be ensured that the second image data after reception is the same image data as the second image data after the first error detection. That is, the result of the first error detection can also be ensured in the second image data after reception. Moreover, when an error is detected in at least one of the first error detection or the second error detection, the projection of light to the projection surface is turned off, so that the image display based on the second image data in which the error occurs is not performed, and the projection surface is in a state where light is not irradiated. Thus, the user can see the background through the screen of the head-up display.

[0105] Furthermore, in the present embodiment, the first error detection circuit obtains a glare index value based on the second image data and performs the first error detection based on the glare index value, wherein the glare index value is an index value indicating glare of the head-up display.

[0106] According to the present embodiment, the first error detection circuit can detect, as a glare error, a state in which the visibility of the background is reduced by the image based on the second image data by performing the first error detection based on the glare index value. Thus, when the glare error is not detected in the first error detection and the second error detection, it is guaranteed that there is no glare error in the second image data received by the receiving interface circuit. In addition, when an error is detected in at least one of the first error detection and the second error detection, the projection of light to the projection surface is turned off, so that the second image data that cannot be guaranteed to have no glare error will not be displayed on the head-up display.

[0107] Furthermore, in the present embodiment, the first error detection circuit converts the second image data into the third image data by inverse mapping processing of the mapping processing, and compares the first image data with the third image data, thereby performing the first error detection.

[0108] According to the present embodiment, by comparing the first image data with the third image data, it is possible to determine whether the mapping process from the first image data to the second image data is normal, and the third image data is obtained by inverse mapping the first image data. Thus, when no error is detected in the first error detection and the second error detection, it is also possible to ensure that there is no mapping process error in the second image data received by the receiving interface circuit. In addition, when an error is detected in at least one of the first error detection or the second error detection, the projection of light to the projection surface is turned off, so it cannot be guaranteed that the second image data without a mapping process error will not be displayed on the head-up display.

[0109] In addition, in this embodiment, the control system may also include a first image circuit and a second image circuit. The first image circuit may also include an image processing circuit, a first error detection circuit, a first error code value generation circuit, and a transmission interface circuit. The second image circuit may also include a second circuit device, and the second circuit device includes a receiving interface circuit and a second error code value generation circuit.

[0110] According to this embodiment, it is ensured that the second image data received by the second circuit device at the subsequent stage is the same image data as the second image data after the first error detection in the first circuit device at the previous stage. Therefore, even if the first circuit device performs the first error detection and a second circuit device is provided at the subsequent stage, the result of the first error detection can be substantially guaranteed in the second circuit device at the subsequent stage. Moreover, in any of the previous stage or the subsequent stage, when the state in which there is no error in the second image data IMB cannot be guaranteed, the projection of light to the projection surface is turned off.

[0111] In addition, in the present embodiment, the control system may also include a third error detection circuit. The image processing circuit may also include: a storage circuit that stores the first image data; and an image conversion circuit that maps the first image data stored in the storage circuit into the second image data. The image conversion circuit may also output reference coordinates representing the pixel position on the first image data, and output the second image data based on the pixel data of the reference coordinates read from the storage circuit based on the output reference coordinates. The third error detection circuit may also perform a third error detection on the reference coordinates output by the image conversion circuit. The control circuit may also output a control signal when an error is detected in at least one of the first error detection, the second error detection, or the third error detection.

[0112] According to the present embodiment, by performing error detection on the reference coordinates output by the image conversion circuit, it is possible to determine whether the coordinate conversion in the mapping process is normal. Thus, when no error is detected in the second error detection and the third error detection, it is also possible to ensure that there is no coordinate conversion error in the second image data received by the receiving interface circuit. In addition, when an error is detected in at least one of the second error detection or the third error detection, the projection of light to the projection surface is turned off, so that the second image data that cannot be guaranteed to have no coordinate conversion error will not be displayed on the head-up display.

[0113] Furthermore, in the present embodiment, the control circuit may output a control signal for turning off the light source of the head-up display.

[0114] According to the present embodiment, when an error is detected in at least one of the first error detection and the second error detection, the light source of the head-up display is turned off, and therefore, an image based on the second image data in which an error has occurred is not displayed.

[0115] Furthermore, in the present embodiment, the control system may include a mask circuit that performs mask processing on the second image data before being transmitted by the transmission interface circuit according to the control signal.

[0116] According to this embodiment, when an error is detected in at least one of the first error detection or the second error detection, the second image data before being transmitted by the transmission interface circuit is masked, so that an image based on the erroneous second image data is not displayed.

[0117] Furthermore, in the present embodiment, the control system may include a mask circuit that performs mask processing on the second image data received by the reception interface circuit according to the control signal.

[0118] According to the present embodiment, when an error is detected in at least one of the first error detection or the second error detection, the second image data received by the reception interface circuit is masked, so that an image based on the erroneous second image data is not displayed.

[0119] Furthermore, an electronic device according to the present embodiment includes: the control system described in any one of the above; and a head-up display.

[0120] In addition, although the present embodiment is described in detail as above, those skilled in the art should be able to easily understand that various modifications can be made without substantially departing from the new matters and effects of the present invention. Therefore, such modifications are all included in the scope of the present invention. For example, in the specification or the drawings, for a term recorded at least once with a different term in a broader sense or synonymous, it can be replaced with the different term at any position in the specification or the drawings. In addition, all combinations of the present embodiment and the modifications are also included in the scope of the present invention. In addition, the structure or action of the image processing device, display controller, processing device, display driver, head-up display, control system, electronic device, etc. are not limited to the contents described in the present embodiment, and various modifications can be implemented.

Claims

1. A control system, characterized in that: It controls the head-up display, which includes: an image processing circuit for mapping the input first image data into second image data for projection onto a projection surface of the head-up display; a first error detection circuit for performing a first error detection on the second image data; a first error code value generating circuit, which generates a first error code value according to the second image data; A sending interface circuit for sending the second image data; a receiving interface circuit for receiving the second image data sent by the sending interface circuit; a second error code value generating circuit, which generates a second error code value according to the second image data received by the receiving interface circuit; a second error detection circuit, which performs a second error detection on the second image data received by the receiving interface circuit according to the first error code value and the second error code value; as well as a control circuit that outputs a control signal for shutting off the projection of light onto the projection surface when an error is detected in at least one of the first error detection or the second error detection, The control system comprises a third error detection circuit, The image processing circuit comprises: a storage circuit storing the first image data; and an image conversion circuit for performing the mapping process so that the first image data stored in the storage circuit becomes the second image data, The image conversion circuit outputs reference coordinates indicating pixel positions on the first image data, and outputs the second image data based on pixel data of the reference coordinates read from the storage circuit based on the output reference coordinates. The third error detection circuit performs a third error detection on the reference coordinates output by the image conversion circuit. The control circuit outputs the control signal when an error is detected in at least one of the first error detection, the second error detection, and the third error detection.

2. The control system according to claim 1, characterized in that: The first error detection circuit obtains a glare index value based on the second image data, and performs the first error detection based on the glare index value, wherein the glare index value is an index value indicating glare of the head-up display.

3. The control system according to claim 1, characterized in that: The first error detection circuit converts the second image data into third image data by an inverse mapping process of the mapping process, and compares the first image data with the third image data, thereby performing the first error detection.

4. The control system according to any one of claims 1 to 3, characterized in that: The control system comprises: a first circuit device comprising the image processing circuit, the first error detection circuit, the first error code value generation circuit and the transmission interface circuit; and A second circuit device includes the receiving interface circuit and the second error code value generating circuit.

5. The control system according to any one of claims 1 to 3, characterized in that: The control circuit outputs the control signal for turning off the light source of the head-up display.

6. The control system according to any one of claims 1 to 3, characterized in that: The control system includes a mask circuit that performs mask processing on the second image data before being transmitted by the transmission interface circuit according to the control signal.

7. The control system according to any one of claims 1 to 3, characterized in that: The control system includes a mask circuit configured to perform a mask process on the second image data received by the receiving interface circuit according to the control signal.

8. An electronic device, characterized in that: It contains: The control system according to any one of claims 1 to 7; and The head-up display.

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