Method for detecting dynamic display delay of VR display screen

Abstract

The present invention provides a method for detecting the dynamic display delay of a VR display screen, and belongs to the field of virtual reality. The method comprises: detecting the posture parameters of the VR display screen in real time; converting the posture parameters of the VR display screen into a virtual scale, and transmitting it to the VR display screen for display in a perspective projection view; acquiring the test image of the detection platform in a moving state in real time, the test image comprising a first area frame image and a second area frame image; determining the dynamic display delay time of the VR display screen according to the number of delayed image frames between the initial delayed frame image and the normal frame image; wherein the initial delayed frame image is a test image where the second area frame image that meets the second preset condition is located; and the normal frame image is a test image where the first area frame image that meets the first preset condition is located. The present invention can improve the accuracy of the dynamic display delay time of the VR display screen and reduce the difficulty of the experiment.

Description

Technical Field

[0001] The present invention relates to the field of virtual reality, and in particular to a method for detecting dynamic display delay of a VR display screen. Background Art

[0002] Motion delay in VR is one of the main causes of dizziness. Motion to photon is an important indicator for evaluating VR experience, so all VR devices must be tested for this indicator during the development process and before they are put on the market to determine whether they can provide users with a good enough experience.

[0003] In VR applications, motion display delay refers to the delay from human movement to the corresponding image changes in the VR display device. Common factors causing motion display delay include gyroscope delay, communication delay, posture algorithm calculation delay, 3D rendering delay, and screen refresh rate. The basic process of testing motion display delay on the market is as follows:

[0004] 1. Place the VR display device on a motion device that can rotate or move horizontally or vertically;

[0005] 2. Set the motion device to rotate or move horizontally or vertically;

[0006] 3. The VR display device displays the rotation angle or movement distance value measured by the sensor of the VR device on the screen;

[0007] 4. Use a camera to record the entire process and record the rotation angle and moving distance of the motion device;

[0008] 5. Compare the value of the motion device at the same time with the value on the VR screen captured by the camera and calculate the difference, which is the motion display delay value

[0009] The general process of posture tracking and image rendering output in VR is as follows:

[0010] 1. Collection of sensor data;

[0011] 2. Sensor fusion algorithm calculation;

[0012] 3. Render the 3D scene based on the posture obtained by the fusion algorithm;

[0013] 4. Output the rendering to the screen for display. In this way, the values ​​of the rotation angle and movement distance on each frame of the image displayed on the screen reflect the latest posture of the VR device.

[0014] Currently, most VR devices cannot meet the requirements of real-time rendering and reduce the motion display delay to below 20ms, so most VR devices will use ATW technology. When the graphics card cannot render in time, the image of the previous frame will be rotated and translated according to the posture obtained by the sensor, and the new frame of the image will be quickly simulated and displayed on the screen immediately to meet the requirements of sufficiently low motion display delay. Because some display frames of VR devices using ATW technology are obtained by rotating and translating the image of the previous frame, if the above method is used to test the motion display delay, the rotation and translation values ​​in the image on the VR screen captured by the camera will be repeated, which cannot reflect the actual posture of the VR device. Summary of the invention

[0015] The purpose of the embodiments of the present invention is to provide a method for detecting motion display delay of a VR display screen, so as to at least solve the problem of delay measurement of VR devices.

[0016] In order to achieve the above object, the present invention provides a method for detecting dynamic display delay of a VR display screen, wherein the VR display screen is fixed to a detection platform, a first mark is provided on the VR display screen, and the detection platform is provided with a mark scale corresponding to the posture parameter of the VR display screen, and the mark scale is used to identify the standard display scale corresponding to the posture parameter of the VR display screen; the method comprises:

[0017] Real-time detection of posture parameters of VR display screen;

[0018] Converting the posture parameters of the VR display screen into a virtual scale, and transmitting the virtual scale to the VR display screen for display in a perspective projection view;

[0019] Acquire a test image of the detection platform in a moving state in real time, wherein the test image includes a first region frame image and a second region frame image; the first region frame image is a captured image of a virtual scale image displayed on a VR display screen under a first identification mark; the second region frame image is a captured image of an identification scale corresponding to a posture parameter of the VR display screen; the first region frame image and the second region frame image are captured at the same time;

[0020] The dynamic display delay time of the VR display screen is determined according to the number of delayed image frames between the initial delayed frame image and the normal frame image; wherein the initial delayed frame image is a test image where the second area frame image that meets the second preset condition is located; and the normal frame image is a test image where the first area frame image that meets the first preset condition is located.

[0021] Optionally, the method further includes: acquiring an initial delayed frame image, including:

[0022] Acquire the identification scale in the second region frame image; the identification scale in the second region frame image includes a scale and an identification;

[0023] The accuracy of the identification scale in the second region frame image is judged, and when the identification scale in the second region frame image and the identification meet the set condition, it is determined that the second region frame image meets the second preset condition;

[0024] The test image where the second region frame image that meets the second preset condition is located is used as the initial delayed frame image.

[0025] Optionally, the method further includes: acquiring a normal frame image, including:

[0026] Obtain a captured image of a virtual scale image displayed on a VR display screen under the first identification mark;

[0027] The accuracy of the first mark and the scale mark image displayed on the VR display screen is judged, and when the first mark and the scale mark displayed on the VR display screen meet the set condition, and the overlapping scale is the same as the overlapping scale that meets the second preset condition, it is determined that the first region frame image meets the first preset condition;

[0028] The test image where the first region frame image that meets the first preset condition is located is used as the normal frame image.

[0029] Optionally, determining the dynamic display delay time of the VR display screen according to the number of delayed image frames between the initial delayed frame image and the normal frame image includes:

[0030] Obtaining the image frame number difference between the initial delayed frame image and the normal frame image;

[0031] The product of the image frame number difference and the interval time between adjacent frames is used as the interval time between the initial delayed frame image and the normal frame image;

[0032] The interval time between the initial delayed frame image and the normal frame image is used as the motion display delay time of the VR display.

[0033] Optionally, the movement mode of the detection platform includes rotational motion; and the posture parameter of the VR display screen includes the azimuth angle of the detection platform.

[0034] Optionally, the movement mode of the detection platform includes linear motion; and the posture parameter of the VR display screen includes the displacement of the detection platform.

[0035] Optionally, converting the posture parameters of the VR display screen into a virtual scale and transmitting the scale to the VR display screen for display in a perspective projection view includes:

[0036] Convert the azimuth angle of the detection platform into a scale directly in front and a corresponding degree value; and

[0037] The scale directly in front and the corresponding degree value are transmitted to the VR display screen in the form of a perspective projection view for display.

[0038] Optionally, converting the posture parameters of the VR display screen into a virtual scale and transmitting the scale to the VR display screen for display in a perspective projection view includes:

[0039] Convert the displacement of the detection platform into the scale of horizontal movement of the VR display screen and the corresponding degree value; and

[0040] The scale of the horizontal movement of the VR display screen and the corresponding degree value are transmitted to the VR display screen in an orthogonal projection view for display.

[0041] Through the above technical scheme, the posture parameters of the VR display screen are converted into virtual scales and transmitted to the VR display screen to be displayed in a perspective projection view; then the collected test image is used to determine the motion display delay time of the VR display screen according to the number of delayed image frames between the initial delayed frame image and the normal frame image in the test image; the accuracy of the motion display delay time of the VR display screen can be improved and the experimental difficulty can be reduced.

[0042] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of the present invention, but do not constitute a limitation on the embodiments of the present invention. In the accompanying drawings:

[0044] Figure 1 is a schematic diagram of a test image provided in an embodiment of the present application;

[0045] Figure 2 is a schematic diagram of another test image provided in an embodiment of the present application;

[0046] Figure 3 is a top view of the horizontal displacement of the detection platform provided in the embodiment of the present application;

[0047] Figure 4 It is a plan view of a rotating detection platform provided in an embodiment of the present application. DETAILED DESCRIPTION

[0048] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0049] The embodiment of the present invention provides a method for detecting dynamic display delay of a VR display screen 6. Figure 4 As shown, the VR display screen 6 is fixed to the detection platform, a first mark 5 is provided on the VR display screen 6, and the detection platform is provided with a mark scale corresponding to the posture parameter of the VR display screen 6, and the mark scale is used to identify the standard display scale corresponding to the posture parameter of the VR display screen 6.

[0050] In a possible embodiment, the movement mode of the detection platform includes rotational motion. During the test, the VR display screen 6 is fixed on the rotating dial 1, and the rotating dial 1 marks the scale and the degree corresponding to the scale on the edge of the turntable; a base 2 is set below the rotating dial 1, and a second mark 3 is set on the base 2 to mark the scale marked on the edge of the turntable and the degree corresponding to the scale (reflecting the real orientation of the glasses). A 1000fps high-speed camera is set above the rotating dial 1. When measuring the dynamic display delay in the rotating state, it is placed above the turntable, and the virtual scale displayed on the VR display screen 6 can be captured at the same time. During the detection process, the high-speed camera continuously captures the turntable scale and the virtual scale displayed on the VR display screen 6; after the detection is completed, the video recorded by the high-speed camera is checked, and the value on the rotating dial 1 indicated by the second mark 3 in the video is the degree of rotation of the rotating dial 1, and the virtual scale 4 indicated by the first mark 5 is the degree of rotation recognized by the VR device.

[0051] A method for detecting dynamic display delay of a VR display screen 6 includes: the VR display screen 6 detects the posture parameters of the VR display screen 6 in real time through a sensor on the main body; the posture parameters of the VR display screen 6 are converted into a virtual scale 4, and transmitted to the VR display screen 6 for display in a perspective projection view; the posture parameters of the VR display screen 6 include the azimuth angle of a detection platform; preferably, the azimuth angle of the detection platform of the VR display screen 6 is converted into a virtual scale 4, and transmitted to the VR display screen 6 for display in a perspective projection view.

[0052] Specifically, the azimuth angle of the detection platform is converted into a scale directly in front and a corresponding degree value; and the scale directly in front and the corresponding degree value are transmitted to the VR display screen 6 in a perspective projection view for display.

[0053] Specifically, the virtual scale 4 is centered on the head, surrounds the head 360 degrees and is divided into 360 degrees by 360 vertical lines, and the degree corresponding to each scale is marked, and the scale and the corresponding degree value in front are displayed in a perspective projection view. The glasses screen is the VR display screen, and the rendering process is: draw a Cartesian coordinate system in front of the head, the plane formed by the xy axis is perpendicular to the line of sight, and the z axis is parallel to the line of sight. Draw scales on each axis at intervals of centimeters and mark the corresponding values, and display the scale and the corresponding distance value in front in an orthogonal projection view.

[0054] Furthermore, the dynamic display delay detection method provided in the present application also includes: acquiring a test image of the detection platform in a moving state in real time, the test image including a first area frame image and a second area frame image; the first area frame image is a captured image of the virtual scale 4 image displayed by the VR display screen 6 under the first identifier 5; the second area frame image is a captured image of the identification scale corresponding to the posture parameter of the VR display screen 6; the first area frame image and the second area frame image are captured at the same time; the first area frame image includes the test image where the virtual scale 4 displayed by the VR display screen 6 and the first identifier 5 are located;

[0055] The dynamic display delay time of the VR display screen 6 is determined according to the number of delayed image frames between the initial delayed frame image and the normal frame image; wherein the initial delayed frame image is a test image where the second area frame image that meets the second preset condition is located; and the normal frame image is a test image where the first area frame image that meets the first preset condition is located.

[0056] Optionally, the method further includes: acquiring an initial delayed frame image, including:

[0057] Obtain the identification scale in the second area frame image; the identification scale in the second area frame image includes a scale and a second mark 3; judge the accuracy of the identification scale in the second area frame image, and when the identification scale in the second area frame image and the second mark 3 meet the set conditions (preferably, the distance between the center line of the identification scale and the second mark 3 belongs to the set interval, and the set interval is 0.1-0.8mm), determine that the second area frame image meets the second preset condition; use the test image where the second area frame image that meets the second preset condition is located as the initial delayed frame image.

[0058] Optionally, the method further includes: acquiring a normal frame image, including:

[0059] Acquire a captured image of the virtual scale 4 image displayed on the VR display screen 6 under the first mark 5; make an accuracy judgment on the first mark 5 and the scale mark image displayed on the VR display screen 6, and determine that the first area frame image satisfies the first preset condition when the first mark 5 and the scale mark displayed on the VR display screen 6 meet the set conditions (preferably, the distance between the center line of the first mark 5 and the scale mark displayed on the VR display screen 6 belongs to the set interval, and the set interval is 0.1-0.8mm), and the overlapping scales are the same as the overlapping scales that meet the second preset condition; and use the test image where the first area frame image that meets the first preset condition is located as the normal frame image.

[0060] Optionally, determining the motion display delay time of the VR display screen 6 according to the number of delayed image frames between the initial delayed frame image and the normal frame image includes: obtaining the image frame number difference between the initial delayed frame image and the normal frame image; taking the product of the image frame number difference and the interval time between adjacent frames as the interval time between the initial delayed frame image and the normal frame image; and taking the interval time between the initial delayed frame image and the normal frame image as the motion display delay time of the VR display screen 6.

[0061] Specifically, Figure 1 As shown, read the scale of the mark in the second area frame image in the test image at time T1 and the scale of the second mark 3 when meeting the set condition is at R1 (360°); check frame by frame in the video captured by the camera to find the first area frame image, such as Figure 2 , the first mark 5 in the screen (VR) points to the image P2 with a degree of R1 (360°), the P1 image is the F1 frame, and the P2 is the F20 frame. The number of frames between the two images P1 and P2 is F20-F1=F△. The high-speed camera is 1000fps, so the interval between each frame is 1ms. The rotational display delay D is as follows: D=F△X 1.

[0062] In a possible embodiment, the movement mode of the detection platform includes linear motion; and the posture parameter of the VR display screen 6 includes the displacement of the detection platform. Figure 3 As shown, further, the displacement of the detection platform of the VR display screen 6 is converted into a virtual scale 4, and transmitted to the VR display screen in a perspective projection view for display. Specifically, the displacement of the detection platform is converted into a scale of horizontal movement of the VR display screen and a corresponding degree value; and the scale of horizontal movement of the VR display screen 6 and the corresponding degree value are transmitted to the VR display screen in an orthogonal projection view for display.

[0063] During the experiment, the VR display screen 6 is fixed on a horizontally moving motion mechanism such as a trolley, and the track under the trolley is provided with a scale; a 1000fps high-speed camera is provided on the trolley, and when measuring the dynamic display delay in the rotating state, it moves with the trolley and marks the scale and distance value (used to indicate the change in the movement distance) on the motion mechanism. The scale of the horizontal movement of the VR display screen 6 and the corresponding degree value are transmitted to the VR display screen in the form of an orthogonal projection view for display. The dynamic display delay time is determined by determining the dynamic display delay time of the VR display screen 6 based on the number of delayed image frames between the initial delayed frame image and the normal frame image. The specific process is the same as the calculation process on the rotating platform.

[0064] Through the above technical scheme, by converting the posture parameters of the VR display screen into a virtual scale and transmitting it to the VR display screen for display in a perspective projection view, and then collecting a test image, the motion display delay time of the VR display screen is determined by determining the number of delayed image frames between the initial delayed frame image and the normal frame image in the test image, the accuracy of the motion display delay time of the VR display screen can be improved and the experimental difficulty can be reduced.

[0065] The optional embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above embodiments. Within the technical concept of the embodiments of the present invention, the technical scheme of the embodiments of the present invention can be subjected to a variety of simple modifications, and these simple modifications all belong to the protection scope of the embodiments of the present invention. It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the embodiments of the present invention will not further describe various possible combinations.

[0066] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the embodiments of the present invention, they should also be regarded as the contents disclosed in the embodiments of the present invention.

Claims

1. A method for detecting dynamic display delay of a VR display screen, wherein the VR display screen is fixed to a detection platform, a first mark is provided on the VR display screen, and the detection platform is provided with a mark scale corresponding to the posture parameter of the VR display screen, and the mark scale is used to identify a standard display scale corresponding to the posture parameter of the VR display screen; characterized in that: The method comprises: Real-time detection of posture parameters of VR display screen; Converting the posture parameters of the VR display screen into a virtual scale, and transmitting the virtual scale to the VR display screen for display in a perspective projection view; Acquire a test image of the detection platform in a moving state in real time, wherein the test image includes a first region frame image and a second region frame image; the first region frame image is a captured image of a virtual scale image displayed on a VR display screen under a first identification mark; the second region frame image is a captured image of an identification scale corresponding to a posture parameter of the VR display screen; and the first region frame image and the second region frame image are captured at the same time; Acquire the identification scale in the second region frame image; the identification scale in the second region frame image includes a scale and a second identification; The accuracy of the identification scale in the second region frame image is judged, and when the identification scale in the second region frame image and the second identification meet the set condition, it is determined that the second region frame image meets the second preset condition; Using the test image where the second region frame image that meets the second preset condition is located as the initial delayed frame image; Obtain a captured image of a virtual scale image displayed on a VR display screen under the first identification mark; The accuracy of the first mark and the scale mark image displayed on the VR display screen is judged, and when the first mark and the scale mark displayed on the VR display screen meet the set condition, and the overlapping scale is the same as the overlapping scale that meets the second preset condition, it is determined that the first region frame image meets the first preset condition; Taking the test image where the first region frame image that meets the first preset condition is located as a normal frame image; Obtaining the image frame number difference between the initial delayed frame image and the normal frame image; The product of the image frame number difference and the interval time between adjacent frames is used as the interval time between the initial delayed frame image and the normal frame image; The interval time between the initial delayed frame image and the normal frame image is used as the motion display delay time of the VR display.

2. The detection method according to claim 1, characterized in that: The movement mode of the detection platform includes rotational motion; the posture parameter of the VR display screen includes the azimuth angle of the detection platform.

3. The detection method according to claim 1, characterized in that: The movement mode of the detection platform includes linear motion; the posture parameter of the VR display screen includes the displacement of the detection platform.

4. The detection method according to claim 2, characterized in that: The step of converting the posture parameters of the VR display screen into a virtual scale and transmitting the scale to the VR display screen for display in a perspective projection view includes: Convert the azimuth angle of the detection platform into a scale directly in front and a corresponding degree value; and The scale directly in front and the corresponding degree value are transmitted to the VR display screen in the form of a perspective projection view for display.

5. The detection method according to claim 3, characterized in that: The step of converting the posture parameters of the VR display screen into a virtual scale and transmitting the scale to the VR display screen for display in a perspective projection view includes: Convert the displacement of the detection platform into the scale of horizontal movement of the VR display screen and the corresponding degree value; and The scale of the horizontal movement of the VR display screen and the corresponding degree value are transmitted to the VR display screen in an orthogonal projection view for display.

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