CN114079768A

CN114079768A - Image definition testing method and device

Info

Publication number: CN114079768A
Application number: CN202110152595.2A
Authority: CN
Inventors: 杨斯曼; 汪燕青; 章晓凌
Original assignee: Hangzhou Haikang Auto Software Co ltd
Current assignee: Hangzhou Haikang Auto Software Co ltd
Priority date: 2020-08-18
Filing date: 2021-02-03
Publication date: 2022-02-22
Anticipated expiration: 2041-02-03
Also published as: CN113450257A; CN113450257B; CN113489972A; CN114079768B

Abstract

The embodiment of the application provides a method and a device for testing the definition of an image, and the scheme comprises the following steps: acquiring a panoramic image and a plurality of single-view images acquired by a panoramic all-around viewing system, wherein the panoramic image is obtained by splicing the single-view images, and each single-view image comprises a graphic card positioned at a test point; and performing definition analysis on the image cards included in the panoramic images to obtain the panoramic definition corresponding to each test point. By applying the technical scheme provided by the embodiment of the application, the definition level of the panoramic image is objectively described.

Description

Image definition testing method and device

Technical Field

The application relates to the technical field of vehicle-mounted panoramic looking-around systems, in particular to a method and a device for testing the definition of an image.

Background

The panoramic all-round looking technology is that images collected by a plurality of cameras are spliced to obtain a panoramic image, and the panoramic image can naturally display the condition of the periphery of a vehicle. The panoramic all-round looking system based on the panoramic all-round looking technology comprises a front-looking camera, a rear-looking camera, a side-looking camera and the like. The definition of the panoramic image is an important index of the imaging quality of the panoramic looking-around system. However, currently, the sharpness level of a panoramic image and a monoscopic image cannot be objectively described.

Disclosure of Invention

The embodiment of the application aims to provide a method and a device for testing the definition of an image so as to objectively describe the definition levels of a panoramic image and a single-view image. The specific technical scheme is as follows:

in a first aspect, an embodiment of the present application provides a method for testing sharpness of an image, where the method includes:

acquiring a panoramic image and a plurality of single-view images acquired by a panoramic all-around viewing system, wherein the panoramic image is obtained by splicing the single-view images, and each single-view image comprises a graphic card positioned at a test point;

and performing definition analysis on the image cards included in each single-view image to obtain the single-view definition corresponding to each test point, and performing definition analysis on the image cards included in the panoramic image to obtain the panoramic definition corresponding to each test point.

Optionally, the panoramic all-around viewing system is installed on a vehicle, the step of analyzing the sharpness of the cards included in each single-view image to obtain the single-view sharpness corresponding to each test point, and the step of analyzing the sharpness of the cards included in the panoramic image to obtain the panoramic sharpness corresponding to each test point includes:

performing definition analysis on a graphic card included in each single-view image to obtain a first single-view definition corresponding to each test point along the vehicle length direction of the vehicle and a second single-view definition corresponding to each test point along the vehicle width direction of the vehicle;

and analyzing the definition of the image card included in the panoramic image to obtain a first panoramic definition corresponding to each test point along the vehicle length direction of the vehicle and a second panoramic definition corresponding to each test point along the vehicle width direction of the vehicle.

Optionally, the graphic card is divided into four blocks by a first straight line and a second straight line passing through the center of the graphic card, the four blocks are alternately distributed according to black blocks and white blocks, an included angle between the first straight line and a first edge of the graphic card is within a preset angle range, an included angle between the second straight line and a second edge of the graphic card is within the preset angle range, the first edge is perpendicular to the second edge, and the first edge is parallel to the vehicle length direction of the vehicle.

Optionally, the step of analyzing the sharpness of the graphic card included in each single-view image to obtain a first single-view sharpness corresponding to each test point along the vehicle length direction of the vehicle and a second single-view sharpness corresponding to each test point along the vehicle width direction of the vehicle includes:

performing definition analysis on at least one horizontal test frame included in each single-view image to obtain first single-view definition corresponding to each test point along the vehicle length direction of the vehicle, wherein the horizontal test frames are located at the alternate positions of the black blocks and the white blocks on the two sides of the second straight line on the graphic card;

performing definition analysis on at least one vertical test frame included in each single-view image to obtain second single-view definition corresponding to each test point along the vehicle width direction of the vehicle, wherein the vertical test frame is located at the position, on the graphic card, of the black block and the white block on two sides of the first straight line in an alternating manner;

the step of analyzing the definition of the image card included in the panoramic image to obtain a first panoramic definition corresponding to each test point along the vehicle length direction of the vehicle and a second panoramic definition corresponding to each test point along the vehicle width direction of the vehicle comprises the following steps:

performing definition analysis on at least one horizontal test frame included in the panoramic image to obtain a first panoramic definition corresponding to each test point along the vehicle length direction of the vehicle;

and performing definition analysis on at least one vertical test frame included in the panoramic image to obtain a second panoramic definition corresponding to each test point along the vehicle width direction of the vehicle.

Optionally, the length and width of the graphic card are greater than or equal to preset lengths, and in the single-view image and the panoramic image, the length and width of the horizontal test frame and the vertical test frame are greater than or equal to preset pixels;

in the single-view image and the panoramic image, the center of the vertical test frame is located on the second straight line, two sides of the vertical test frame are parallel to the first side, the center of the horizontal test frame is located on the first straight line, and two sides of the horizontal test frame are parallel to the second side.

Optionally, each test point is located on a reference line which is a preset distance away from the body of the vehicle.

Optionally, the distance between every two adjacent test points is the same, the number of the test points along the vehicle length direction of the vehicle is not less than a first number, the number of the test points along the vehicle width direction of the vehicle is not less than a second number, and the vertex of the datum line is provided with the test points, wherein the first number is greater than the second number.

Optionally, a projection of the center of the graphic card on the ground coincides with the test point, and one edge of the graphic card is parallel to the reference line.

Optionally, one edge of the graphic card is located on the ground between the reference line and the body of the vehicle, and is parallel to the reference line.

Optionally, the graphic cards are placed on the test points sequentially or simultaneously;

when the panoramic image is a two-dimensional panoramic image, the graphic card is horizontally placed on the ground; when the panoramic image is a three-dimensional panoramic image, the graphic card is vertically placed on the ground, and the distortion coefficient of the graphic card in the panoramic image is lower than a preset distortion threshold value.

Optionally, the plane where the graphic card is located is perpendicular to an optical axis of a camera included in the panoramic all-around viewing system.

Optionally, the graphics card is mounted on a movable test rig.

Optionally, the test bench includes movable support, height adjuster and angle adjuster, height adjuster install on the movable support and for the height-adjustable on ground, angle adjuster install on the movable support and for the inclination on ground adjustable, the picture card with height adjuster and angle adjuster fixed connection.

Optionally, the method further includes:

and if the panoramic definition corresponding to each test point is greater than or equal to a preset minimum panoramic definition threshold value, determining that the panoramic definition requirement is met.

Optionally, the method further includes:

and if the number of the standard test points in the vehicle length direction of the vehicle exceeds a preset proportion threshold value of the total number of the test points in the vehicle length direction of the vehicle and the number of the standard test points in the vehicle width direction of the vehicle exceeds a preset proportion threshold value of the total number of the test points in the vehicle width direction of the vehicle, the panoramic definition requirement is met, and the panoramic definition corresponding to the standard test points is greater than a preset standard definition threshold value.

Optionally, the method further includes:

and if the single vision definition corresponding to each test point is greater than or equal to a preset lowest single vision definition threshold value, determining that the single vision definition requirement is met.

Optionally, the method further includes:

aiming at each camera included in the panoramic all-round viewing system, acquiring the width of the visual field range of the camera as the visual field width and the standard width in the visual field range of the camera, wherein the standard width is the width of the visual field range of which the panoramic definition is higher than a preset reference definition threshold value; calculating the ratio of the standard width to the field width to obtain a clear ratio; and if the definition ratio is greater than or equal to a preset definition threshold, determining that the panoramic definition requirement is met.

Optionally, the step of acquiring the width of the field of view of the camera as the field of view width and the standard width of the field of view of the camera includes:

aiming at each camera included in the panoramic all-round viewing system, drawing a panoramic definition curve based on the panoramic definition corresponding to each test point in the visual field range of the camera, wherein the ordinate of the panoramic definition curve is the panoramic definition, and the abscissa of the panoramic definition curve is the position of the test point; taking the width of the abscissa between the end points on the two sides of the panoramic definition curve as the field width of the field range of the camera; taking the width of the abscissa between the first intersection point and the second intersection point as the standard width in the visual field range of the camera;

and the first intersection point and the second intersection point are points on the panoramic definition curve, wherein the panoramic definition is the preset reference definition threshold value.

Optionally, the method further includes:

determining a definition loss value corresponding to each test point based on the single-view definition and the panoramic definition corresponding to each test point; and if the definition loss value corresponding to each test point is less than or equal to a preset loss threshold, determining that the definition requirement is met.

Optionally, the step of determining the sharpness loss value corresponding to each test point based on the monoscopic sharpness and the panoramic sharpness corresponding to each test point includes:

for each test point, determining definition loss value S corresponding to the test point by using the following formula_{Loss of power}：

S_{Loss of power}＝(Q₁-Q₂)/Q₁；

Wherein Q is₁Representing the monoscopic sharpness, Q, of the test point correspondences₂And expressing the panoramic definition corresponding to the test point.

In a second aspect, an embodiment of the present application provides an apparatus for testing sharpness of an image, where the apparatus includes:

the panoramic system comprises an acquisition unit, a display unit and a display unit, wherein the acquisition unit is used for acquiring a panoramic image and a plurality of single-view images acquired by the panoramic all-around system, the panoramic image is obtained by splicing the single-view images, and each single-view image comprises a graphic card positioned at a test point;

and the analysis unit is used for carrying out definition analysis on the image cards included in each single-view image to obtain the single-view definition corresponding to each test point, and carrying out definition analysis on the image cards included in the panoramic image to obtain the panoramic definition corresponding to each test point.

Optionally, the panoramic all-round looking system is installed on a vehicle, and the analysis unit is specifically configured to:

Optionally, the analysis unit is specifically configured to:

Optionally, the distance between two adjacent test points is the same, the number of the test points along the vehicle length direction of the vehicle is not less than a first number, the number of the test points along the vehicle width direction of the vehicle is not less than a second number, and the test points are arranged at the top of the datum line, wherein the first number is greater than the second number.

Optionally, the graphics card is mounted on a movable test rig.

Optionally, the analysis unit is further configured to:

Optionally, the analysis unit is specifically configured to:

Optionally, the analysis unit is further configured to:

Optionally, the analysis unit is specifically configured to:

S_{Loss of power}＝(Q₁-Q₂)/Q₁；

In the technical scheme provided by the embodiment of the application, a panoramic image and a plurality of single-view images collected by a panoramic all-around system are obtained, the panoramic image is obtained by splicing the plurality of single-view images, and each single-view image comprises a graphic card positioned at a test point; and performing definition analysis on the image cards included in the panoramic image to obtain the panoramic definition corresponding to each test point, thereby realizing objective description of the definition levels of the panoramic image and the single-view image.

Of course, not all advantages described above need to be achieved at the same time in the practice of any one product or method of the present application.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art that other embodiments can be obtained by using the drawings without creative efforts.

Fig. 1 is a schematic view of a field of view of a camera according to an embodiment of the present disclosure;

FIG. 2 is a schematic diagram of an apparatus arrangement provided by an embodiment of the present application;

FIG. 3 is a schematic diagram of an SFR test chart provided in an embodiment of the present application;

fig. 4 is a schematic flowchart of a method for testing sharpness of an image according to an embodiment of the present disclosure;

fig. 5 is a schematic diagram of test point deployment provided in an embodiment of the present application;

fig. 6 is another schematic diagram of test point deployment provided in the embodiment of the present application;

FIG. 7 is a schematic diagram of a graphics card deployment provided by an embodiment of the present application;

FIG. 8 is a schematic view of a graphics card provided in accordance with an embodiment of the present application;

FIG. 9 is a schematic diagram of a test box on a graphics card according to an embodiment of the present disclosure;

FIG. 10 is a schematic diagram of a single test box provided by an embodiment of the present application;

FIG. 11 is a schematic view of a test rack provided in accordance with an embodiment of the present application;

FIG. 12 is a schematic view of a panoramic sharpness curve provided in an embodiment of the present application;

fig. 13 is a schematic diagram of a positional relationship between an optical axis of a camera and a graphic card according to an embodiment of the present disclosure;

fig. 14 is a schematic structural diagram of an apparatus for testing sharpness of an image according to an embodiment of the present disclosure.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

For convenience of understanding, words appearing in the embodiments of the present application are explained below.

Panoramic View Monitor System (AVMS): an image type driving auxiliary system is composed of an Electronic Control Unit (ECU) and a plurality of cameras. And the ECU performs processing such as distortion reduction, visual angle conversion, image splicing and the like on the images collected by the cameras according to parameters such as the installation angles of the cameras around the vehicle body, lens distortion and the like, and converts the images into a real-time panoramic aerial view overlooking the periphery of the vehicle body from a certain point in the air.

In the embodiment of the present application, the number of cameras included in the panoramic all-round viewing system may be 4, 6, 8, and the like, and is not limited specifically. The following description will be given taking an example in which the panoramic looking-around system includes 4 cameras. The panoramic all-round looking system comprises 4 cameras which are divided into a front-view camera, a rear-view camera, a left-view camera and a right-view camera. The 4 trapezoidal regions shown in fig. 1 are the viewing ranges of the 4 cameras, respectively, where a region a1 is the viewing range of the front-view camera, a region a2 is the viewing range of the rear-view camera, a region a3 is the viewing range of the left-view camera, and a region a4 is the viewing range of the right-view camera.

Spatial Frequency Response (SFR): is a multi-valued metric measuring the contrast loss as a function of spatial frequency. The magnitude of the SFR value represents the degree of sharpness of the image.

Modulation Transfer Function (MTF): is a reference value. The MTF50P value refers to the SFR value after reducing the peak energy to half the original value.

Camera Calibration (CC): the method is the basis for obtaining the panoramic image by splicing the single-view images and comprises internal reference calibration and external reference calibration. The internal reference calibration is to obtain the focal length, the main optical axis, the distortion coefficient and the like of the camera. The external reference calibration is key data required for generating the single-view image stitching. In general, external reference calibration is a necessary link of a production process of the panoramic all-round viewing system.

Operating mode B1: the test sample piece (namely the camera) is normally electrically connected, all functions are normally operated, and external display equipment is required.

Testing points: is the place for placing the graphic card on the ground.

In this embodiment of the application, the images collected by the cameras may be referred to as single-view images collected by a panoramic looking-around system, and the real-time panoramic aerial view may be referred to as a panoramic image collected by the panoramic looking-around system.

In order to objectively describe the definition levels of a panoramic image and a single-view image acquired by a panoramic all-around system, the embodiment of the application provides a method for testing the definition of the image. The method for testing the definition of the image can be used for testing the definition of the image collected by a panoramic all-around system arranged on various vehicles. The vehicle provided with the panoramic all-round viewing system can be various operation vehicles, such as passenger cars, trucks, saloon cars and the like, and further, the operation vehicles can be M1, M2, M3, N1, N2, N3, O type operation vehicles and the like. Wherein, M1, M2, M3, N1, N2, N3 and O all represent vehicle types.

In the embodiment of the application, before the image is subjected to the definition test, a plurality of cameras included in the panoramic all-around system can be calibrated in advance. After calibration, the pitch angles of the multiple cameras are the same, and the single-view images acquired by the multiple cameras are spliced to obtain a panoramic image. The panoramic all-around viewing system after calibration is applicable to scenes such as indoor and outdoor sunny days, outdoor rainy days, outdoor sunny nights, outdoor rainy nights and the like.

In the embodiment of the application, the site for testing the definition of the image is a real vehicle closed site, and the test definition of the real vehicle closed site meets the preset requirement. For example, the preset requirements may include the following:

A11) within the panoramic visual range of the panoramic all-round viewing system, when a 2-meter guiding rule is used for measurement, the deviation of the ground flatness is not more than 5 mm;

B12) the ground is made of neutral gray or matte material with black gray;

C13) in a normal illumination scene test, the illumination in a field is uniform, and the illumination deviation of each place is not more than 10%;

D14) in low light scenes, the in-field illumination is controlled to within (2 ± 0.2) lux (lx).

In one embodiment, in a field where images are subjected to sharpness testing, lighting conditions may be deployed according to relevant regulations on lighting in ISO12233: 2000.

The preset requirements can be set according to actual requirements. For example, the preset requirements may also include the following points:

A21) before the definition test is started, mounting and setting a panoramic all-round looking system according to relevant instructions provided by a panoramic all-round looking manufacturer; after the definition test is started, the sensor installation and the system setting are not allowed to be changed;

B22) it is necessary to distinguish between a test in an unloaded state and a test in a fully loaded state of the vehicle.

In the embodiment of the application, before each camera is installed on the panoramic all-around system, the definition test can be performed, that is, before each camera is installed on the panoramic all-around system, the image collected by each camera meets the definition requirement.

According to the device layout diagram shown in fig. 2, a camera, a test chart and the like are arranged. The camera is a Device Under Test (DUT). The test chart is shown in fig. 3. The camera independent of the panoramic all-round looking system is tested in a working mode B1 according to the following steps, and the test result meets the requirements of the table 1:

a11) adjusting the distance between the camera and the test graphic card to ensure that the length of the grid edge on the test graphic card in the image is not less than 10 pixels;

b12) adjusting the camera to enable the edge of the square on the test chart card at the central view field of the camera to form an included angle of about 5 degrees with the corresponding direction;

c13) adjusting the camera to enable the optical axis of the camera to be orthogonal to the plane of the graphic card, and analyzing the MTF50P value at the central view field of the camera by using image processing software;

d14) the camera is horizontally or vertically rotated, so that the square grids on the test chart are positioned at 70% of the visual field of the camera, and the length of the edges of the square grids on the test chart is not less than 10 pixels;

e15) the MTF50P values at 70% field of view of the camera were analyzed using image analysis software. Unit: LW/PH

TABLE 1

For a standard definition camera, when a definition test is performed on an image, MTF50P values of National Television Standards Committee (NTSC) color gamut and MTF50P values of PAL (Phase Alteration Line, PAL) color coding are obtained respectively. For a high-definition camera, when a definition test is carried out on an image, MTF50P values of 100 ten thousand-level pixels and MTF50P values of 200 ten thousand-level pixels are obtained respectively.

Based on the panoramic all-round system and the real vehicle closed field, as shown in fig. 4, the method for testing the definition of the image provided by the embodiment of the application comprises the following steps:

step S41, acquiring a panoramic image and a plurality of single-view images collected by the panoramic looking-around system, wherein the panoramic image is obtained by splicing the plurality of single-view images, and each single-view image comprises a graphic card positioned at a test point;

step S42, performing definition analysis on the image cards included in each single-view image to obtain the single-view definition corresponding to each test point, and performing definition analysis on the image cards included in the panoramic image to obtain the panoramic definition corresponding to each test point.

In the above step S41, the panoramic looking-around system is mounted on the vehicle. The vehicle provided with the panoramic all-round viewing system is parked in a field with uniform ambient illumination, such as the real vehicle closed field. A plurality of test points can be arranged on the field.

In the embodiment of the application, the test point and the graphic card can meet the requirements:

a21) each test point is located on a reference line at a predetermined distance from the body of the vehicle. The preset distance can be set according to actual requirements. For example, the preset distance may be adjusted within 0 meter (m) to 10m, and the preset distance may be 1m, 1.5m, 2m, 3m, 4m, and the like.

For example, as shown in fig. 5, the visual field of a camera includes 10 test points, which are (r), (c) and (c) test points located on datum line L₁Upper, the reference line L₁The distance between the car body and the car body is 1m, namely the preset distance is 1 m.

For another example, as shown in fig. 6, 16 test points, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O and P, respectively, are provided around the vehicle body. The 16 test points are each located on a reference line at a distance d from the vehicle body.

Points at different distances and different angles have different definitions in the image. In the embodiment of the application, the distances from all the test points to the vehicle body are the same, so that the quantitative analysis of the definition of the panoramic all-around image is facilitated.

b22) The distance between every two adjacent test points is the same, the test points not less than a first number are included along the vehicle length direction of the vehicle, the test points not less than a second number are included along the vehicle width direction of the vehicle, the top points of the datum lines are provided with the test points, and the first number is larger than the second number.

The vehicle length direction can be from the head to the tail or from the tail to the head. The vehicle width direction may be a direction from the left side to the right side of the vehicle body, or a direction from the right side to the left side of the vehicle body. The first number and the second number can be set according to actual requirements. For example, the first number is 7 and the second number is 3. As shown in fig. 6, A, B, C, D, E, F, G test points are deployed on one side in the vehicle length direction, and I, J, K, L, M, N, O test points are deployed on the other side in the vehicle length direction; the 3 test points G, H, I are disposed along one side in the vehicle width direction, and the 3 test points O, P, A are disposed along the other side in the vehicle width direction. Wherein A, I, G, O the 4 test points are located at the apex of the reference line.

In an alternative embodiment, the first number and the second number are at least 3, i.e. the number of test points comprised in the field of view of each camera is at least 3.

For example, as shown in fig. 1, the 4 test points are located at the center of the visual field of the front-view camera, the rear-view camera, the left-view camera and the right-view camera, respectively, and the 4 test points are located at the splicing position of two adjacent cameras, respectively. The central position of the field of view of the camera may be understood as the central position of the image captured by the camera. At this time, each camera includes 3 test points within the field of view. And sixthly, splicing positions of the 4 test points are the vertexes of the datum lines.

In the embodiment of the application, the vertex of the datum line is positioned at the splicing position of two adjacent cameras. And the test points are arranged at the top points of the reference lines, so that the definition of the spliced position in the panoramic image can be tested more clearly, and the definition of the panoramic image obtained after splicing can be evaluated accurately.

c23) The projection of the center of the card on the ground coincides with the test point and one edge of the card is parallel to the reference line, as shown in fig. 6 and 7.

d24) One edge of the card is located on the ground between the reference line and the body of the vehicle and is parallel to the reference line. As shown in fig. 6 and 7, the side l of the chart is located on the ground between the reference line and the body of the vehicle, and is parallel to the reference line.

e25) The drawing card is divided into four blocks by a first straight line and a second straight line which pass through the center of the drawing card, the four blocks are alternately distributed according to black blocks and white blocks, the included angle between the first straight line and the first edge of the drawing card is within a preset angle range, the included angle between the second straight line and the second edge of the drawing card is within a preset angle range, the first edge is perpendicular to the second edge, and the first edge is parallel to the length direction of a vehicle.

The structure of the graphic card is shown in fig. 8. In FIG. 8, line l₁Is a first straight line, straight line l₂Is a second straight line. Straight line l₁And a straight line l₂The graphics card is divided into four blocks. The preset angle range can be set according to actual requirements. For example, the preset angle range may be 0 ° to 10 °. In order to ensure accurate testing, the surface of the graphic card is required to be matt and flat.

f26) The length and the width of the graph card are more than or equal to the preset length; in the single-view image and the panoramic image, the length and the width of the horizontal test frame and the vertical test frame are both larger than or equal to the preset pixels. The horizontal test frame is located at the position, on the graph card, of the second straight line, where the black blocks and the white blocks on the two sides alternate, and the vertical test frame is located at the position, on the graph card, of the first straight line, where the black blocks and the white blocks on the two sides alternate. As shown in fig. 9,

vertical test blocks

1 and 3, and

horizontal test blocks

2 and 4.

In the embodiment of the application, the oblique edge of the test frame is ensured to be long enough as far as possible while avoiding the connection between the edge of the graphic card and the black block, as shown in fig. 9. Here, the oblique side is a part of the first straight line or the second straight line.

In an alternative embodiment, in the monoscopic image and the panoramic image, the center of the vertical test frame is located on the second straight line, two sides of the vertical test frame are parallel to the first side, the center of the horizontal test frame is located on the first straight line, and two sides of the horizontal test frame are parallel to the second side. As shown in fig. 10.

Wherein, preset length can be set according to actual need. For example, the preset length may be 2m, 3m, etc. The preset pixels can be set according to actual requirements. For example, the preset pixels may be 10 pixels, 20 pixels, and the like. When the preset pixel is 20 pixels, the test frame (including the horizontal test frame and the vertical test frame) is greater than or equal to 20 pixels by 20 pixels.

In the embodiment of the application, when the panoramic image is a two-dimensional panoramic image, the graphic card can be horizontally placed on the ground; when the panoramic image is a three-dimensional panoramic image, the graphic card can be vertically placed on the ground, and the distortion coefficient of the graphic card in the panoramic image is lower than a preset distortion threshold value.

Wherein, the card can be vertically placed on the ground, and the card can be understood to be not horizontally placed on the ground. The concrete can be represented as follows: the side of the card that is on the ground is closer to the vehicle than the side of the card that is away from the ground, as shown in FIG. 7.

In an optional embodiment, in order to minimize the distortion coefficient of the graphic card in the panoramic image, the plane where the graphic card is located is perpendicular to the optical axis of the camera included in the panoramic looking-around system.

In the embodiment of the application, the graphic card can be placed on each test point at the same time. At this time, the sharpness test can be performed based on the panoramic image and the single-view image acquired by the panoramic all-around system at one time. The graphic card may also be placed on each test point in turn. At this time, the sharpness test may be performed based on the panoramic image and the monoscopic image acquired by the panoramic looking-around system for a plurality of times.

In an alternative embodiment, the graphics card is mounted on a movable test rig to facilitate adjustment of the position of the graphics card.

In order to facilitate the adjustment of the posture of the graphic card, the test bench as shown in fig. 11 may include a movable support 111, a height adjuster 112 and an angle adjuster 113, the height adjuster 112 is mounted on the movable support 111 and is adjustable in height with respect to the ground, the angle adjuster 113 is mounted on the movable support 111 and is adjustable in inclination angle with respect to the ground, and the graphic card is fixedly connected to the height adjuster 112 and the angle adjuster 113.

In the embodiment of the present application, the movement of the graphic card can be realized by moving the movable bracket 111; the angle of the angle adjuster 113 is adjusted to adjust the inclination angle of the graphic card; by adjusting the height of the height adjuster 112, the adjustment of the height of the graphic card can be achieved.

In the embodiment of the application, the graphic card is installed on the test bench, the height and the angle of the graphic card can be adjusted, the test bench can be arranged around a vehicle, the graphic card is placed at the test point, and the graphic card is suitable for the test of the definition of two-dimensional and three-dimensional panoramic images. In addition, the test site is not required to be arranged again under the condition that the vehicle is replaced, and the test cost and the labor cost are saved.

In the embodiment of the application, one test bench can be sequentially placed at each test point, so that the panoramic all-around vision system respectively collects the single-view image and the panoramic image comprising the graphic card, and then the single-view definition and the panoramic definition corresponding to each test point are obtained through analysis.

In the embodiment of the application, a plurality of test racks can be simultaneously placed at each test point, that is, the number of the test racks is the same as that of the test points. Therefore, the panoramic all-round looking system comprises a plurality of cameras which respectively collect a single-view image, and the single-view definition and the panoramic definition corresponding to each test point can be obtained through analysis.

In the step S42, after the panoramic image and the monoscopic images are obtained, each monoscopic image is imported into image analysis software, the sharpness of the cards included in each monoscopic image is analyzed to obtain the monoscopic sharpness corresponding to each test point, the panoramic image is imported into the image analysis software, and the sharpness of the cards included in the panoramic image is analyzed to obtain the panoramic sharpness corresponding to each test point.

In an alternative embodiment, the definition may be divided into a definition in the vehicle length direction and a definition in the vehicle width direction. In this case, the step S42 may be: performing definition analysis on the image card included in each single-view image to obtain a first single-view definition corresponding to each test point along the vehicle length direction of the vehicle and a second single-view definition corresponding to each test point along the vehicle width direction of the vehicle; and carrying out definition analysis on the image cards included in the panoramic image to obtain a first panoramic definition corresponding to each test point along the vehicle length direction of the vehicle and a second panoramic definition corresponding to each test point along the vehicle width direction of the vehicle.

In an optional embodiment, in order to ensure that the test is accurate, the step of performing sharpness analysis on the graphics card included in each single-view image to obtain a first single-view sharpness corresponding to each test point in the vehicle length direction of the vehicle and a second single-view sharpness corresponding to each test point in the vehicle width direction of the vehicle may specifically be: performing definition analysis on at least one horizontal test frame included in each single-view image to obtain a first single-view definition corresponding to each test point along the vehicle length direction of the vehicle; and performing definition analysis on at least one vertical test frame included in each single-view image to obtain a second single-view definition corresponding to each test point along the vehicle width direction of the vehicle.

The step of analyzing the sharpness of the image card included in the panoramic image to obtain a first panoramic sharpness corresponding to each test point along the vehicle length direction of the vehicle and a second panoramic sharpness corresponding to each test point along the vehicle width direction of the vehicle may specifically be: performing definition analysis on at least one horizontal test frame included in the panoramic image to obtain a first panoramic definition corresponding to each test point along the vehicle length direction of the vehicle; and performing definition analysis on at least one vertical test frame included in the panoramic image to obtain a second panoramic definition corresponding to each test point along the vehicle width direction of the vehicle.

In the embodiment of the application, as shown in fig. 9, when the first monoscopic resolution and the first panoramic resolution are tested, the selected horizontal test frames may be test frames 2 and/or 4; when testing the second single-view sharpness and the second panoramic sharpness, the selected vertical test frame may be the test frame 1 and/or 3.

Based on the image definition testing method provided by the embodiment of the application, the definition of each testing point meets at least one of the following requirements:

a31) the panoramic definition is greater than or equal to a preset lowest panoramic definition threshold value. That is, if the panoramic definition corresponding to each test point is greater than or equal to the preset minimum panoramic definition threshold, it is determined that the panoramic definition requirement is met.

The preset minimum panoramic definition threshold value can be set according to actual requirements. For example, the preset lowest panorama definition threshold may be 100, 110 or 120, etc. In the embodiment of the application, the preset lowest panoramic definition threshold value can be set according to actual requirements. The preset minimum panoramic definition threshold can meet the requirement of minimum resolution which can be resolved by human eyes. This ensures that the user's visual needs for the panoramic image are met.

In practical applications, the position with the lowest resolution in the panoramic image is the stitching position, such as the test point in r in fig. 5, and then the test point A, G, I, O in fig. 6. Therefore, whether the panoramic definition of the test point at the splicing position is greater than or equal to the preset lowest panoramic definition threshold value or not can be directly detected. And if the panoramic definition corresponding to the test point at the splicing position is greater than or equal to a preset minimum panoramic definition threshold value, determining that the panoramic definition requirement is met.

b32) In the vehicle length direction or the vehicle width direction of the vehicle, the number of the test points with the panoramic definition higher than the preset standard definition threshold value on the single side of the vehicle exceeds the preset proportion threshold value of the test points on the single side of the vehicle. That is, if the number of the standard test points along the vehicle length direction of the vehicle exceeds the preset proportional threshold of the total number of the test points along the vehicle length direction of the vehicle, and the number of the standard test points along the vehicle width direction of the vehicle exceeds the preset proportional threshold of the total number of the test points along the vehicle width direction of the vehicle, the panoramic definition requirement is met, and the panoramic definition corresponding to the standard test points is greater than the preset standard definition threshold.

The preset standard definition threshold value can be set according to actual requirements. For example, the preset standard definition threshold may be 200, 210, or 220, etc. The preset proportion threshold value can be set according to actual requirements. For example, the preset proportion threshold may be 60%, 70%, 75%, or the like.

In one example, the standard definition threshold is preset to be 200 and the predetermined proportion threshold is 60%. In this case, if the number of the test points with the panoramic visibility on the left side of the vehicle being greater than 200 exceeds 60% of the total number of the test points on the left side of the vehicle, the number of the test points with the panoramic visibility on the right side of the vehicle being greater than 200 exceeds 60% of the total number of the test points on the right side of the vehicle, the number of the test points with the panoramic visibility on the front side of the vehicle being greater than 200 exceeds 60% of the total number of the test points on the front side of the vehicle, and the number of the test points with the panoramic visibility on the rear side of the vehicle being greater than 200 exceeds 60% of the total number of the test points on the rear side of the vehicle.

c33) The monoscopic resolution is greater than or equal to a preset lowest monoscopic resolution threshold. That is, if the monoscopic resolution corresponding to each test point is greater than or equal to the preset lowest monoscopic resolution threshold, the requirement of the monoscopic resolution is determined to be met.

The preset lowest single-view sharpness threshold value can be set according to actual requirements. For example, the preset minimum single vision sharpness threshold may be 200, 210, or 220, etc.

In the embodiment of the application, the preset lowest single-view sharpness threshold value can be set according to actual requirements. The preset lowest single-vision definition threshold can meet the requirement of the minimum resolution which can be resolved by human eyes. Therefore, the visual requirement of the user on the single-view image can be ensured to be met.

In practice, the location in the monoscopic image where sharpness is lowest is the location of the splice, e.g., the test point in r in fig. 5, and further e.g., the test point A, G, I, O in fig. 6. Therefore, whether the single vision definition of the test point at the splicing position is larger than or equal to the preset lowest single vision definition threshold value or not can be directly detected. And if the single vision definition corresponding to the test point at the splicing position is greater than or equal to a preset lowest single vision definition threshold value, determining that the single vision definition requirement is met.

In the embodiment of the application, the definition at the test point can also meet the following requirements:

a41) aiming at each camera included in the panoramic all-round looking system, acquiring the width of the field of view range of the camera as the field of view width; acquiring a standard width in a visual field range of the camera, wherein the standard width is the width of the visual field range with the panoramic definition higher than a preset reference definition threshold; calculating the ratio of the standard width to the field width to obtain a clear ratio; and if the definition ratio is greater than or equal to a preset definition threshold, determining that the panoramic definition requirement is met.

The field of view of the camera is conical. The field width and the standard width may be determined based on the width of the field of view at the location of the test point. For example, if the distance between the test point and the vehicle body is 1m, the width of the field of view at the distance of 1m from the vehicle body may be used as the field of view width of the camera.

In an optional embodiment, for each camera included in the panoramic all-round viewing system, based on the panoramic definition corresponding to each test point in the visual field range of the camera, drawing a panoramic definition curve, wherein the ordinate of the panoramic definition curve is the panoramic definition, and the abscissa of the panoramic definition curve is the position of the test point; taking the horizontal coordinate width between the end points on the two sides of the panoramic definition curve as the view field width of the view field of the camera; taking the width of the abscissa between the first intersection point and the second intersection point as the standard width in the visual field range of the camera; and the first intersection point and the second intersection point are points on the panoramic definition curve, wherein the panoramic definition is a preset reference definition threshold value.

Take the distribution diagram of the test points shown in fig. 5 as an example. In fig. 5, r ((r) () r) (test point) is in the visual field of camera head over in fig. 5), r (r) () r (test point) is at splicing position), (r) ((r) () r ((0) () r ((1) () r (2)) test point is in the order of r → → r (r) () r → r (0). Acquiring the panoramic clarity corresponding to the test point of r 3, and drawing a panoramic clarity curve based on the panoramic clarity corresponding to the test point of r 4, as shown in curve 1 in fig. 12. In fig. 12, the abscissa is the position of the test point, and the ordinate is the panoramic resolution. Leftmost end point x of curve 1₁Corresponding to the test point (i), the extreme point x on the rightmost side of the curve 1₂Corresponding to test point (r), end point (x)₁Corresponding abscissa is A, end point x₂The corresponding abscissa is B. Distance L between points A and B_ABI.e. the field width of the field of view of the upper camera in fig. 5. The point on the curve 1 where the panoramic resolution is the preset reference resolution threshold is x₃And x₄. Point x₃Corresponding to the abscissa as a, point x₄The corresponding abscissa is b. Distance L between points a and b_abNamely in fig. 5Standard width in the field of view of the upper camera. At this time, the clear ratio w is L_ab/L_AB。

b42) Determining a definition loss value corresponding to each test point based on the single-view definition and the panoramic definition corresponding to each test point; and if the definition loss value corresponding to each test point is less than or equal to a preset loss threshold, determining that the definition requirement is met.

In one example, for each test point, the definition loss value S 'corresponding to the test point is determined by the following formula'_{Loss of power}：

S'_{Loss of power}＝Q₁-Q₂

In the embodiment of the application, whether the panoramic all-around system tested at present meets the factory requirements or not can be determined according to the definition loss, so that the candidate right to maintain of a user or the quantitative detection of factory vehicle factory leaving is facilitated.

In another example, for each test point, the definition loss value S corresponding to the test point is determined by the following formula_{Loss of power}：

S_{Loss of power}＝(Q₁-Q₂)/Q₁；

Panoramic all-round looking system on different vehicles, the pitch angle of camera and the quantity of camera are not identical, accord with the Q that the definition required₁And Q₂The difference is not exactly the same size. In the embodiment of the present application, the above-mentioned S is utilized_{Loss of power}Formula, calculating definition loss, and looking around the corresponding Q of panoramic system on different vehicles₁And Q₂The difference value of the vehicle-mounted panoramic all-around system is normalized, so that the panoramic all-around system on different vehicles can be managed in a unified mode.

In an embodiment of the present application, when any of the above definition requirements is not satisfied, an alarm message may be output, and the alarm message indicates that the panoramic looking-around system does not meet factory requirements.

The following describes the sharpness tests of the 2D panoramic image and the 3D panoramic image, respectively. 4 cameras that the system includes is looked around to the panorama are look ahead camera, back vision camera, left side look camera and right side look camera respectively, and the position of test point is shown in figure 1.

The testing process of the 2D panoramic image comprises the following steps:

sa1, after finishing the calibration process of the vehicle, the user drives the vehicle into the place meeting the light regulation.

The vehicle calibration process comprises the step of calibrating a plurality of cameras included in the panoramic all-around system, so that the pitch angles of the cameras are the same, and the panoramic images obtained by splicing the images collected by the cameras comprise the panoramic view around the vehicle. The above-mentioned lighting regulations may be as in ISO12233:2000 regarding lighting, e.g. lighting uniformity.

Sa2, the user lays the graphic card horizontally at 8 test points on the ground, and the distance between the graphic card and the vehicle body is a preset distance.

Sa3, acquiring a 2D panoramic image output by the panoramic all-round looking system and a single-view image collected by each camera.

Sa4, converting the 2D panoramic image into a first file recognizable by image analysis software.

S5, analyzing the first file by using image analysis software to obtain the corresponding panoramic definition of each test point

Sa6, converting the single-view image into a second file recognizable by image analysis software.

In the embodiment of the present application, the execution sequence of Sa6 and Sa4 is not limited.

Sa7, analyzing the second file by using image analysis software to obtain the single-view definition corresponding to each test point.

Sa8, after obtaining the single vision definition and the panoramic definition corresponding to each test point, a panoramic definition curve and a single vision definition curve can be drawn. The ordinate of the single-vision definition curve is the single-vision definition, and the abscissa of the single-vision definition curve is the position of the test point. This facilitates viewing and analysis by the user, and comparison of monoscopic sharpness and panoramic sharpness versus standard sharpness.

3D panoramic image testing process:

sb1, after completing the calibration process of the vehicle, the user drives the vehicle into a place meeting the lighting regulation.

Sb2, the user moves the test bed close to the vehicle body, adjusts the height adjuster to change the height of the graphic card so that the center of the graphic card is located in the monoscopic image, and adjusts the angle adjuster to change the tilt angle of the graphic card so that the plane of the graphic card is perpendicular to the optical axis of the camera, as shown in fig. 13.

At the moment, the area of the graphic card in the single-view image or the panoramic image is the largest, so that the test of the definition is facilitated.

And Sb3, acquiring a 3D panoramic image output by the panoramic all-around viewing system and a single-view image acquired by each camera.

Sb4, the 3D panoramic image is converted into a third file recognizable by image analysis software.

Sb5, analyzing the third file by using image analysis software to obtain the corresponding panoramic definition of each test point

Sb6, convert the single-view image into a fourth file recognizable by image analysis software.

In the embodiment of the present application, the execution sequence of Sb6 and Sb4 is not limited.

And Sb7, analyzing the fourth file by using image analysis software to obtain the single-view definition corresponding to each test point.

Sb8, after obtaining the single vision definition and the panoramic definition corresponding to each test point, a splicing definition curve and a single vision definition curve can be drawn. The ordinate of the single-vision definition curve is the single-vision definition, and the abscissa of the single-vision definition curve is the position of the test point. This facilitates viewing and analysis by the user.

In the embodiment of the present application, the sharpness, such as monoscopic sharpness and panoramic sharpness, is divided into horizontal sharpness and vertical sharpness, and the analysis methods of the horizontal sharpness and the vertical sharpness are the same, so that the sharpness is uniformly used for description, and is not limited. The horizontal definition is the definition in the vehicle length direction, and the vertical definition is the definition in the vehicle width direction.

Based on the above method for testing the sharpness of an image, an embodiment of the present application further provides a device for testing the sharpness of an image, as shown in fig. 14, the device includes:

the acquiring unit 141 is configured to acquire a panoramic image acquired by the panoramic looking-around system and a plurality of single-view images, where the panoramic image is an image obtained by splicing the plurality of single-view images, and each single-view image includes a graphic card located at a test point;

the analyzing unit 142 is configured to perform sharpness analysis on the cards included in each single-view image to obtain a single-view sharpness corresponding to each test point, and perform sharpness analysis on the cards included in the panoramic image to obtain a panoramic sharpness corresponding to each test point.

In an alternative embodiment, the panoramic looking-around system is installed on a vehicle, and the analysis unit 142 may be specifically configured to:

performing definition analysis on the image card included in each single-view image to obtain a first single-view definition corresponding to each test point along the vehicle length direction of the vehicle and a second single-view definition corresponding to each test point along the vehicle width direction of the vehicle;

and carrying out definition analysis on the image cards included in the panoramic image to obtain a first panoramic definition corresponding to each test point along the vehicle length direction of the vehicle and a second panoramic definition corresponding to each test point along the vehicle width direction of the vehicle.

In an optional embodiment, the graphic card is divided into four blocks by a first straight line and a second straight line passing through the center of the graphic card, the four blocks are alternately distributed according to black blocks and white blocks, an included angle between the first straight line and a first edge of the graphic card is within a preset angle range, an included angle between the second straight line and a second edge of the graphic card is within a preset angle range, the first edge is perpendicular to the second edge, and the first edge is parallel to the vehicle length direction of the vehicle.

In an alternative embodiment, the analyzing unit 142 may be specifically configured to:

performing definition analysis on at least one horizontal test frame included in each single-view image to obtain first single-view definition corresponding to each test point along the vehicle length direction of the vehicle, wherein the horizontal test frame is positioned at the alternate positions of black blocks and white blocks on two sides of a second straight line on the graphic card;

performing definition analysis on at least one vertical test frame included in each single-view image to obtain second single-view definition corresponding to each test point along the vehicle width direction of the vehicle, wherein the vertical test frame is positioned at the alternate positions of black blocks and white blocks on two sides of a first straight line on the graphic card;

In an optional embodiment, the length and width of the graphic card are greater than or equal to preset lengths, and in the single-view image and the panoramic image, the length and width of the horizontal test frame and the vertical test frame are greater than or equal to preset pixels;

in the single-view image and the panoramic image, the center of the vertical test frame is positioned on the second straight line, two edges of the vertical test frame are parallel to the first edge, the center of the horizontal test frame is positioned on the first straight line, and two edges of the horizontal test frame are parallel to the second edge.

In an alternative embodiment, each test point is located on a reference line at a predetermined distance from the body of the vehicle.

In an optional embodiment, the distance between every two adjacent test points is the same, no less than a first number of test points are included along the vehicle length direction of the vehicle, no less than a second number of test points are included along the vehicle width direction of the vehicle, and the vertex of the datum line is provided with the test points, wherein the first number is larger than the second number.

In an alternative embodiment, the projection of the center of the card on the ground coincides with the test point, and one edge of the card is parallel to the reference line.

In an alternative embodiment, one edge of the card is located on the ground between the datum line and the body of the vehicle and is parallel to the datum line.

In an optional embodiment, the graphic cards are placed on the test points sequentially or simultaneously;

In an alternative embodiment, the plane in which the graphic card is located is perpendicular to the optical axis of a camera included in the panoramic looking around system.

In an alternative embodiment, the graphics card is mounted on a movable test rig.

In an alternative embodiment, the test bench comprises a movable support, a height adjuster and an angle adjuster, wherein the height adjuster is mounted on the movable support and is adjustable in height relative to the ground, the angle adjuster is mounted on the movable support and is adjustable in inclination angle relative to the ground, and the graphic card is fixedly connected with the height adjuster and the angle adjuster.

In an alternative embodiment, the analyzing unit 142 may further be configured to:

if the number of the standard test points in the vehicle length direction of the vehicle exceeds a preset proportion threshold value of the total number of the test points in the vehicle length direction of the vehicle, and the number of the standard test points in the vehicle width direction of the vehicle exceeds a preset proportion threshold value of the total number of the test points in the vehicle width direction of the vehicle, the panoramic definition requirement is met, and the panoramic definition corresponding to the standard test points is greater than the preset standard definition threshold value.

aiming at each camera included in the panoramic all-round looking system, drawing a panoramic definition curve based on the panoramic definition corresponding to each test point in the visual field range of the camera, wherein the ordinate of the panoramic definition curve is the panoramic definition, and the abscissa of the panoramic definition curve is the position of the test point; taking the horizontal coordinate width between the end points on the two sides of the panoramic definition curve as the view field width of the view field of the camera; taking the width of the abscissa between the first intersection point and the second intersection point as the standard width in the visual field range of the camera;

and the first intersection point and the second intersection point are points on the panoramic definition curve, wherein the panoramic definition is a preset reference definition threshold value.

for each test point, the following formula is utilizedDetermining definition loss value S corresponding to the test point_{Loss of power}：

S_{Loss of power}＝(Q₁-Q₂)/Q₁；

In the above embodiments, the implementation may be wholly or partially realized by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, cause the processes or functions described in accordance with the embodiments of the application to occur, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another, for example, from one website site, computer, server, or data center to another website site, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, Digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device, such as a server, a data center, etc., that incorporates one or more of the available media. The usable medium may be a magnetic medium (e.g., floppy Disk, hard Disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., Solid State Disk (SSD)), among others.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

All the embodiments in the present specification are described in a related manner, and the same and similar parts among the embodiments may be referred to each other, and each embodiment focuses on the differences from the other embodiments. Particularly, for the embodiment of the apparatus for testing the sharpness of the panoramic view image, since it is substantially similar to the embodiment of the method, the description is relatively simple, and for the relevant points, reference may be made to the partial description of the embodiment of the method.

The above description is only for the preferred embodiment of the present application and is not intended to limit the scope of the present application. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application are included in the protection scope of the present application.

Claims

1. A method for testing sharpness of an image, the method comprising:

2. The method of claim 1, wherein the panoramic all-round system is installed on a vehicle, and the steps of performing sharpness analysis on the card included in each single-view image to obtain the single-view sharpness corresponding to each test point, and performing sharpness analysis on the card included in the panoramic image to obtain the panoramic sharpness corresponding to each test point comprise:

3. The method of claim 2, wherein the graphic card is divided into four blocks by a first straight line and a second straight line passing through a center of the graphic card, the four blocks are alternately distributed according to black blocks and white blocks, an angle between the first straight line and a first side of the graphic card is within a preset angle range, an angle between the second straight line and a second side of the graphic card is within the preset angle range, the first side is perpendicular to the second side, and the first side is parallel to a vehicle length direction of the vehicle.

4. The method of claim 3, wherein the step of performing a sharpness analysis on the graphics included in each single-view image to obtain a first sharpness of single-view along a vehicle length direction of the vehicle corresponding to each test point and a second sharpness of single-view along a vehicle width direction of the vehicle corresponding to each test point comprises:

5. The method of claim 4, wherein the length and width of the graphic card are greater than or equal to preset lengths, and the length and width of the horizontal test frame and the vertical test frame are greater than or equal to preset pixels in the single-view image and the panoramic image;

6. The method of claim 2, wherein each of the test points is located on a reference line at a predetermined distance from a body of the vehicle.

7. The method of claim 6, wherein the distance between every two adjacent test points is the same, no less than a first number of test points are included in the vehicle length direction of the vehicle, no less than a second number of test points are included in the vehicle width direction of the vehicle, and test points are disposed at the vertex of the datum line, wherein the first number is greater than the second number.

8. A method according to claim 6 or 7, wherein the projection of the centre of the card onto the ground coincides with the test point and one edge of the card is parallel to the datum.

9. The method of claim 8, wherein one edge of the graphic card is located on the ground between the reference line and the body of the vehicle and is parallel to the reference line.

10. The method of claim 1, wherein the graphic cards are placed on the respective test points sequentially or simultaneously;

11. The method of claim 10, wherein the plane of the graphic card is perpendicular to an optical axis of a camera included in the panoramic looking around system.

12. The method of claim 10, wherein the graphics card is mounted on a movable test rig.

13. The method of claim 12, wherein the test rig comprises a movable support, a height adjuster mounted on the movable support and adjustable in height relative to the ground, and an angle adjuster mounted on the movable support and adjustable in tilt angle relative to the ground, the graphic card being fixedly connected to the height adjuster and the angle adjuster.

14. The method of claim 1, further comprising:

15. The method of claim 2, further comprising:

16. The method of claim 1, further comprising:

17. The method of claim 1, further comprising:

18. The method of claim 17, wherein the step of acquiring the width of the field of view of the camera as the field of view width and the standard width of the field of view of the camera comprises:

19. The method of claim 1, further comprising:

20. The method of claim 19, wherein the step of determining a sharpness loss value corresponding to each test point based on the monoscopic sharpness and the panoramic sharpness corresponding to each test point comprises:

S_{Loss of power}＝(Q₁-Q₂)/Q₁；

21. An apparatus for testing sharpness of an image, the apparatus comprising:

22. The apparatus of claim 21, wherein the panoramic looking around system is mounted on a vehicle, and the analysis unit is specifically configured to:

23. The apparatus of claim 22, wherein the graphic card is divided into four blocks by a first line and a second line passing through a center of the graphic card, the four blocks are alternately distributed according to black blocks and white blocks, an angle between the first line and a first side of the graphic card is within a preset angle range, an angle between the second line and a second side of the graphic card is within the preset angle range, the first side is perpendicular to the second side, and the first side is parallel to a vehicle length direction of the vehicle.

24. The apparatus according to claim 23, wherein the analysis unit is specifically configured to:

25. The apparatus of claim 24, wherein the length and width of the graphic card are greater than or equal to preset lengths, and the length and width of the horizontal test frame and the vertical test frame are greater than or equal to preset pixels in the monoscopic image and the panoramic image;

26. The apparatus of claim 22, wherein each of the test points is located on a reference line at a predetermined distance from a body of the vehicle.

27. The apparatus of claim 26, wherein the distance between every two adjacent test points is the same, no less than a first number of test points are included in the vehicle length direction of the vehicle, no less than a second number of test points are included in the vehicle width direction of the vehicle, and test points are disposed at the apex of the reference line, wherein the first number is greater than the second number.

28. The apparatus of claim 26 or 27, wherein the projection of the centre of the card onto the ground coincides with the test point and one edge of the card is parallel to the reference line.

29. The apparatus of claim 28 wherein one edge of the graphic card is located on the ground between the datum line and the body of the vehicle and is parallel to the datum line.

30. The apparatus of claim 21, wherein the graphic cards are placed on the respective test points sequentially or simultaneously;

31. The apparatus of claim 30, wherein the plane of the graphic card is perpendicular to an optical axis of a camera included in the panoramic looking around system.

32. The apparatus of claim 30, wherein the graphics card is mounted on a movable test rig.

33. The apparatus of claim 32, wherein the test rig comprises a movable support, a height adjuster mounted on the movable support and adjustable in height relative to the ground, and an angle adjuster mounted on the movable support and adjustable in tilt angle relative to the ground, the graphic card being fixedly connected to the height adjuster and the angle adjuster.

34. The apparatus of claim 21, wherein the analysis unit is further configured to:

35. The apparatus of claim 22, wherein the analysis unit is further configured to:

36. The apparatus of claim 21, wherein the analysis unit is further configured to:

37. The apparatus of claim 21, wherein the analysis unit is further configured to:

38. The apparatus according to claim 37, wherein the analysis unit is specifically configured to:

39. The apparatus of claim 21, wherein the analysis unit is further configured to:

40. The device according to claim 39, wherein the analysis unit is specifically configured to:

S_{Loss of power}＝(Q₁-Q₂)/Q₁；