Ranging method, device, equipment and endoscope system

Abstract

The invention relates to the technical field of distance measurement, provides a distance measurement method, device and equipment and an endoscope system, and can ensure that the size of observation equipment meets the requirement and the image quality is ensured while distance measurement is realized. The method comprises the following steps: acquiring an image formed by an imaging module when a light source module irradiates a shot object; determining a first mapping relation according to the light intensity of the light source module during irradiation and the included angle between the optical axis of the light source module and the irradiated surface of the shot object; and determining the distance between the observation equipment provided with the imaging module and the shot object according to the pixel value of the image and the first mapping relation.

Description

Technical Field

[0001] The present application relates to the field of distance measurement technology, and in particular to a distance measurement method, device, computer equipment, endoscope system, storage medium and computer program product. Background Art

[0002] The observation device uses its own imaging module to shoot certain objects, thus having the function of observing the subject. If the observation environment is dark, the light source module can be used to illuminate the subject to improve the observation effect. Based on the observation results obtained with the help of the observation device, other operations can be performed, and some operations may require obtaining the distance between the observation device and the subject.

[0003] When the observation device is used for observation in a narrow space, the size of the observation device should not be too large. Therefore, it is difficult to install a dedicated distance measurement module, such as a multi-eye camera or a phase difference sensor, in the observation device. In order to ensure that the size of the observation device meets the requirements, some distance measurement methods are to change the pixels used for imaging in the imaging module to pixels used for distance measurement. However, this method will lead to poor image quality. Summary of the invention

[0004] Based on this, it is necessary to provide a ranging method, device, computer equipment, endoscope system, storage medium and computer program product to address the above technical problems.

[0005] The present application provides a ranging method, the method comprising:

[0006] Acquire an image formed by the imaging module when the light source module illuminates the subject;

[0007] Determining a first mapping relationship according to the light intensity of the light source module during illumination and the angle between the optical axis of the light source module and the illuminated surface of the object;

[0008] The distance between an observation device provided with the imaging module and the photographed object is determined according to the pixel value of the image and the first mapping relationship.

[0009] In one embodiment, determining the first mapping relationship according to the light intensity of the light source module during illumination and the angle between the optical axis of the light source module and the illuminated surface of the object includes:

[0010] Selecting a mapping relationship of the first type as the first mapping relationship from among a plurality of pre-constructed mapping relationships of the first type according to the light intensity of the light source module during illumination and the angle between the optical axis of the light source module and the illuminated surface of the object;

[0011] Among them, each of the mapping relationships of the type is associated with a mapping parameter; each group of the mapping parameters includes angle data and light intensity data, and the angle data and light intensity data included in different mapping parameters are not completely the same; the mapping relationship of the type is obtained by multiple groups of first test data corresponding to the mapping parameters associated with the mapping relationship of the type itself; each group of the first test data includes pixel values ​​and distances.

[0012] In one embodiment, before determining the first mapping relationship according to the light intensity of the light source module during illumination and the angle between the optical axis of the light source module and the illuminated surface of the object, the method further includes:

[0013] Determining the bright area and the dark area of ​​the image;

[0014] The angle between the optical axis of the light source module and the illuminated surface is obtained according to the ratio of the pixel values ​​between the bright area and the dark area.

[0015] In one embodiment, determining the bright area and the dark area of ​​the image includes:

[0016] The image is divided into regions along N directions to determine N region groups; wherein the N directions are associated one-to-one with the N region groups; each region group includes two regions located on both sides of the associated direction; and the N directions are different from each other;

[0017] The intra-group pixel differences of the N area groups are obtained, and the bright area and the dark area are determined according to the area group having the largest intra-group pixel difference.

[0018] In one embodiment, when N is 2,

[0019] The step of dividing the image into regions along N directions to determine N region groups includes:

[0020] The image is divided into regions along a first direction and a second direction perpendicular to each other to obtain two region groups; the region group associated with the first direction includes a first region and a second region, and the first region and the second region are located on both sides of the first direction; the region group associated with the second direction includes a third region and a fourth region, and the third region and the fourth region are located on both sides of the second direction;

[0021] The obtaining of the pixel differences of the respective N area groups within the group includes:

[0022] Obtaining a pixel difference degree of an area within a group of areas associated with the first direction according to a pixel value difference degree between the first area and the second area;

[0023] According to the pixel value difference between the third area and the fourth area, the intra-group area pixel difference of the area group associated with the second direction is obtained.

[0024] In one embodiment, when N is 4,

[0025] The step of dividing the image into regions along N directions to determine N region groups includes:

[0026] The image is divided into regions along a first direction and a second direction perpendicular to each other, and along a third direction and a fourth direction perpendicular to each other, to obtain four region groups; the region group associated with the first direction includes a first region and a second region, and the first region and the second region are located on both sides of the first direction; the region group associated with the second direction includes a third region and a fourth region, and the third region and the fourth region are located on both sides of the second direction; the region group associated with the third direction includes a fifth region and a sixth region, and the fifth region and the sixth region are located on both sides of the third direction; the region group associated with the fourth direction includes a seventh region and an eighth region, and the seventh region and the eighth region are located on both sides of the fourth direction;

[0027] The obtaining of the pixel differences of the respective N area groups within the group includes:

[0028] Obtaining a pixel difference degree of an area within a group of areas associated with the first direction according to a pixel value difference degree between the first area and the second area;

[0029] Obtaining a pixel difference degree of an area within a group of areas associated with the second direction according to a pixel value difference degree between the third area and the fourth area;

[0030] Obtaining a pixel difference degree of an area within a group of areas associated with the third direction according to a pixel value difference degree between the fifth area and the sixth area;

[0031] According to the pixel value difference between the seventh region and the eighth region, the pixel difference within the region group associated with the fourth direction is obtained.

[0032] In one embodiment, obtaining the angle between the optical axis of the light source module and the illuminated surface according to the ratio of the pixel values ​​between the bright area and the dark area includes:

[0033] According to the ratio of pixel values ​​between the bright area and the dark area, and the second mapping relationship, the angle between the optical axis of the light source module and the illuminated surface is obtained; the second mapping relationship is obtained based on multiple groups of second test data; each group of the second test data contains bright and dark pixel value ratio data and angle data.

[0034] In one embodiment, the pixel values ​​of the image include pixel values ​​corresponding to the illuminated surface in the image; before determining the distance between the observation device and the photographed object according to the pixel values ​​of the image and the first mapping relationship, the method further includes:

[0035] Determining a target area corresponding to the illuminated surface from the image;

[0036] Statistical processing is performed on the pixel values ​​of the target area to obtain pixel values ​​corresponding to the illuminated surface in the image.

[0037] In one embodiment, the illuminated surface is a surface of a preset part of the photographed object;

[0038] Determining the distance between the observation device and the photographed object according to the pixel value of the image and the first mapping relationship includes:

[0039] The distance between the observation device and the preset part is determined according to the pixel value corresponding to the surface of the preset part in the image and the first mapping relationship.

[0040] The present application provides a distance measuring device, the device comprising:

[0041] An image acquisition unit, used to acquire an image formed by the imaging module when the light source module illuminates the subject;

[0042] A mapping relationship determining unit, configured to determine a first mapping relationship according to the light intensity of the light source module during illumination and an angle between the optical axis of the light source module and the illuminated surface of the object;

[0043] A distance acquisition unit is used to determine the distance between an observation device provided with the imaging module and the photographed object according to the pixel value of the image and the first mapping relationship.

[0044] The present application provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the above method.

[0045] The present application provides an endoscope system, which includes an endoscope, a light source generator, a display, and the computer device described in the above embodiment; the endoscope is provided with the imaging module and the light guide component of the light source module.

[0046] In one embodiment, the optical axis of the light guiding component is parallel to the optical axis of the lens module of the imaging module.

[0047] The present application provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program is executed by a processor to execute the above method.

[0048] The present application provides a computer program product, on which a computer program is stored, and the computer program is executed by a processor to perform the above method.

[0049] The present application can utilize the imaging module and the light source module to complete the distance measurement, and there is no need to add other dedicated distance measurement modules in the observation device, thereby ensuring that the volume of the observation device meets the requirements while achieving the distance measurement; and, the present application determines the first mapping relationship based on the light intensity of the light source module when irradiating the subject, and the angle between the optical axis of the light source module and the illuminated surface of the subject when irradiating; based on the first mapping relationship and the pixel value of the image formed by the imaging module during irradiation, the distance between the observation device and the subject can be obtained, without changing the pixels used for imaging in the imaging module to pixels used for distance measurement, thereby ensuring the image quality while achieving the distance measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 A diagram showing an application environment of a distance measurement method in an embodiment;

[0051] FIG. 2( a ) is a diagram showing an application environment of a distance measurement method in another embodiment;

[0052] FIG2( b ) is a diagram showing an application environment of a distance measurement method in yet another embodiment;

[0053] Figure 3 A schematic diagram of analyzing the relationship between a light source module, an imaging module and a photographed object in one embodiment;

[0054] Figure 4 is a schematic diagram of the relationship between the angle θ and the light intensity entering the lens module in one embodiment;

[0055] Figure 5 is a schematic diagram of the relationship between distance and pixel value in one embodiment;

[0056] Figure 6 is a flow chart of a distance measurement method in one embodiment;

[0057] Figure 7 is a schematic diagram of the light and dark distribution on the surface of a photographed object in one embodiment;

[0058] Figure 8 Schematic diagram of the relationship between the ratio of bright to dark pixel values ​​and the angle γ in one embodiment;

[0059] FIG9( a ) is a schematic diagram of dividing an image area along a first direction in one embodiment;

[0060] FIG9( b ) is a schematic diagram of dividing an image area along a second direction in one embodiment;

[0061] FIG9( c ) is a schematic diagram of dividing an image region along a third direction in one embodiment;

[0062] FIG9( d ) is a schematic diagram of dividing an image region along a third direction in one embodiment;

[0063] Fig.10 is a structural block diagram of a distance measuring device in one embodiment;

[0064] Fig.11 is an internal structure diagram of a computer device in one embodiment;

[0065] Fig.12 is a schematic diagram of the architecture of an endoscope system in one embodiment;

[0066] Fig.13 FIG. 4 is a schematic diagram of the structure of a light source module and an imaging module in an embodiment. DETAILED DESCRIPTION

[0067] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0068] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0069] The distance measurement method proposed in this application is based on the principle of the first law of illumination (illuminance is proportional to the light intensity of the light source, and inversely proportional to the square of the distance from the illuminated surface to the light source). While ensuring that the volume of the observation device meets the requirements and the image quality, the distance between the observation device and the subject is measured. The method is simple and the calculation is quick.

[0070] The method involves Figure 1The imaging module and light source module are shown. A device provided with an imaging module can provide an observation function and can be called an observation device. The light source module can irradiate light to the outside by self-luminescence or by light conduction. When the light source module irradiates by self-luminescence, the light source module may include a light source generator; when the light source module irradiates by light conduction, the light source module may include a light guide component, such as an optical fiber.

[0071] When the observation environment is narrow, if the light source module is not large, the light source module can be placed in the observation device as a part of the observation device. Alternatively, the light source module can be placed outside the observation device as a part independent of the observation device.

[0072] The following descriptions are all based on an example in which the light source module irradiates light to the outside through light conduction.

[0073] In the light transmission method, the light source module includes a light guide component, and the light guide component can be placed in an observation device, such as an endoscope.

[0074] The object photographed by the imaging module may be referred to as a photographed object. Before photographing, the light source generator may be controlled to generate light, and the light is conducted to the vicinity of the photographed object via the light guide component to illuminate the photographed object.

[0075] When the light source module illuminates the subject, the imaging module can be controlled to shoot the subject to obtain an image. When the imaging module may include the lens module, image sensor and signal processing module shown in FIG2(a), specifically, after the light is irradiated to the subject, a reflection phenomenon occurs, and after the reflected light passes through the lens module, it is sensed by the image sensor, and the image sensor outputs a corresponding signal, which is processed by the signal processing module to form an image. The processing of the signal processing module may include digital-to-analog conversion processing.

[0076] The surface of the object illuminated by the light source module can be called the illuminated surface. Regardless of the shape of the object, when the area illuminated by the light source module is small, the curvature is also small, and the illuminated surface can be approximately regarded as a plane.

[0077] 2(b), when the angle between the optical axis of the light source module and the illuminated surface becomes smaller, the light intensity entering the lens module becomes weaker, the signal output by the image sensor also weakens, and the pixel value of the image (denoted as P) decreases. When the light source module irradiates by light conduction, the optical axis of the light source module can be the optical axis of the light guide component.

[0078] Reference Figure 3, the optical axis of the light source module is extended and intersects with the illuminated surface of the subject. The intersection point can be recorded as O, and a point on the optical axis of the light source module is recorded as A. Therefore, the optical axis of the light source module can be represented by line OA. Two points on the optical axis of the lens module are recorded as C and D respectively, and thus, the optical axis of the lens module can be represented by line CD. When the point where the optical axis of the lens module exits the lens module is set to C, the line between point O and the lens module can be represented by line OC. Among them, the optical axis of the light source module is related to the structure of the light source module itself, and the optical axis of the lens module is related to the structure of the lens module itself.

[0079] Angle γ is the angle between line OA and the illuminated surface of the subject, angle β is the angle between line OC and the illuminated surface of the subject, angle α is the angle between line OA and line OC, and angle θ is the angle between line OC and line CD.

[0080] In a scene where the light illuminating the subject is emitted by the light source module, the intensity of the light entering the lens module is affected by the following factors:

[0081] (1) The light intensity of the light source module when irradiating the object (denoted as I);

[0082] (2) Angle γ;

[0083] (3) Angle β;

[0084] (4) The distance from the light source module to the illuminated surface (denoted as d1);

[0085] (5) The distance from the illuminated surface to the lens module (denoted as d2);

[0086] (6) Angle θ.

[0087] Therefore, we can get the factors affecting the intensity of light entering the lens module (I, γ, β, d1, d2, θ). Since the intensity of light entering the lens module is proportional to P, the factors affecting P also include (I, γ, β, d1, d2, θ).

[0088] Assume that the distance between the light source module and the lens module is d3. When the light source module and the lens module are very close, d3 approaches 0, so d1≈d2 can be made, and d=d1=d2 can be made. In addition, when the light source module and the lens module are very close, d3 approaches 0, and the angle α approaches 0, so β=α+γ≈γ. For example, in actual applications, when the light source module and the lens module are both located at the head end of the endoscope, the two are very close to each other (in actual applications, the distance d3 between the light source module and the lens module is often only a few millimeters), while the distance d1 between the object and the light source module, and the distance d2 between the object and the lens module are much larger than d3. At this time, the angle α approaches 0, so the approximate value β=α+γ≈γ can be taken.

[0089] When the angle θ is 0, the light intensity entering the lens module reaches the maximum value. In actual tests, it is found that when the angle θ fluctuates within a small range around 0 degrees, that is, when the angle θ is between (-θ0, +θ0), the difference between the value of the light intensity entering the lens module and the maximum value is very small, such as Figure 4 As shown. Therefore, when the angle θ floats in the range of (-θ0, +θ0), its influence on P can be regarded as a constant. The specific value of (-θ0, +θ0) can be obtained by the technicians according to the actual observation of the equipment. For example, in some embodiments, θ0 can be any value between 5 degrees and 15 degrees.

[0090] When the light source module is very close to the lens module and the angle θ∈(-θ0,+θ0), the influencing factors of P (I, γ, β, d1, d2, θ) can be simplified to (I, γ, d). Among them, d can be d1 or d2 (since d1≈d2, both can be d). When I and γ are fixed, the mapping relationship between d and P can be obtained in advance through calibration experimental tests. When applied, the distance between the observation device and the subject can be obtained based on the mapping relationship between d and P obtained in advance. Since the present application also involves mapping relationships between other quantities, in order to distinguish different mapping relationships, the mapping relationship between d and P is called a class of mapping relationships.

[0091] In the test scenario of the calibration experiment, when constructing a type of mapping relationship, multiple groups of mapping parameters can be set. Each group of mapping parameters includes angle data and light intensity data, the angle data corresponds to the above angle γ, and the light intensity corresponds to the above I. The angle data and light intensity data included in different groups of mapping parameters are not completely the same.

[0092] As shown in Table 1, it is a schematic data of mapping parameters of a type of mapping relationship provided by an embodiment of the present application. In the embodiment of the present application, the angle data γ1 included in the first group of mapping parameters is different from the angle data γ2 included in the second group of mapping parameters, and the light intensity data I1 included in the first group of mapping parameters is different from the light intensity data I2 included in the third group of mapping parameters.

[0093] Mapping Parameters First test data A type of mapping relationship <![CDATA[First group I1, γ1]]> <![CDATA[(P 11 ,d 11 )、(P 12 ,d 12 )、(P 13 ,d 13 )、......]]> <![CDATA[d=f1(P)]]> <![CDATA[Second group I1, γ2]]> <![CDATA[(P 21 ,d 21 )、(P 22 ,d 22 )、(P 23 ,d 23 )、......]]> <![CDATA[d=f2(P)]]> <![CDATA[The third group I2, γ1]]> <![CDATA[(P 31 ,d 31 )、(P 32 ,d 32 )、(P 33 ,d 33 )、......]]> <![CDATA[d=f3(P)]]> <![CDATA[Fourth group I2, γ2]]> <![CDATA[(P 41 ,d 41 )、(P 42 ,d 42 )、(P 43 ,d 43 )、......]]> <![CDATA[d=f4(P)]]>

[0094] Table 1

[0095] After setting multiple groups of mapping parameters, multiple groups of test data corresponding to each group of mapping parameters can be obtained. Since the present application also involves test data when constructing other mapping relationships, in order to distinguish each other, the test data involved in constructing a type of mapping relationship is referred to as the first test data. Each group of first test data includes: a pixel value and a distance value, the distance value is the distance d between the observation device and the subject, and the pixel value is the pixel value P of the image formed by the imaging module when the light source module illuminates the subject. In the calibration experiment, the values ​​of I and γ can be controlled according to the mapping parameters, and then by adjusting different d values ​​and detecting the corresponding P values, multiple groups of first test data (P, d) can be obtained. Referring to Table 1, for the first group of mapping parameters (I1, γ1), multiple groups of first test data (P 11 ,d 11 )、(P 12 ,d 12 )、(P 13 ,d 13 ),.......

[0096] Next, based on the multiple groups of first test data corresponding to the same group of mapping parameters, a type of mapping relationship associated with the group of mapping parameters can be obtained. Specifically, the multiple groups of first test data corresponding to the same group of mapping parameters can be fitted to obtain a type of mapping relationship associated with the group of mapping parameters. The obtained type of mapping relationship can be as follows: Figure 5 A monotonic function is shown.

[0097] Referring to Table 1, the first group of mapping parameters (I1, γ1) corresponding to (P 11 ,d 11 )、(P 12 ,d 12 )、(P 13 ,d 13 ) and other first test data are fitted to obtain a type of mapping relationship d=f1(P) associated with the first group of mapping parameters (I1, γ1). Similarly, a type of mapping relationship d=f2(P) associated with the second group of mapping parameters (I1, γ2), a type of mapping relationship d=f3(P) associated with the third group of mapping parameters (I2, γ1), and a type of mapping relationship d=f4(P) associated with the second group of mapping parameters (I2, γ2) can also be obtained, thereby obtaining multiple type-one mapping relationships, and each type-one mapping relationship is associated with a mapping parameter.

[0098] In the application scenario, the device equipped with the ranging module can perform Figure 6The distance between the observation device and the object is obtained by following the steps shown. The distance measuring module can be provided in the observation device, or it can be provided outside the observation device, in other computer devices with computing capabilities. For example, when the observation device is an endoscope, the distance measuring module can be a device with computing capabilities such as an image processor. The following takes the distance measuring module provided in the computer device as an example. Figure 6 The steps shown include:

[0099] Step S601 : acquiring an image formed by the imaging module when the light source module illuminates the object.

[0100] In practical applications, the light source module can irradiate light to the object through self-luminescence or light conduction, so that the reflected light of the object can be reflected to the imaging module, and the imaging module forms an image of the object.

[0101] Step S602: determining a first mapping relationship according to the light intensity of the light source module during illumination and the angle between the optical axis of the light source module and the illuminated surface of the object.

[0102] From the above analysis, it can be seen that when the light intensity I and the angle γ between the optical axis of the light source module and the illuminated surface of the subject are fixed, there is a certain mapping relationship (i.e., a type of mapping relationship) between the image pixel value P and the distance d between the observation device and the subject. At the same time, the embodiment of the present application pre-establishes multiple type-one mapping relationships through calibration experiments. Based on this, the embodiment of the present application can first obtain the light intensity I and the angle γ when the light source module is irradiated. Then, based on the light intensity I and the angle γ, a specific type of mapping relationship that is adapted is selected from multiple type-one mapping relationships (the selected type of mapping relationship is referred to as the first mapping relationship in this application).

[0103] For example, if the light intensity of the light source module during illumination is I1, and the angle between the optical axis of the light source module and the illuminated surface is γ1, the computer device can obtain the current mapping parameter as (I1, γ1). At this time, multiple first-class mapping relationships are queried, and it can be determined that the first-class mapping relationship corresponding to the current mapping parameter (I1, γ1) is d=f1(P), and then d=f1(P) is used as the first mapping relationship.

[0104] Step S603: determining the distance between the observation device provided with the imaging module and the photographed object according to the pixel value of the image and the first mapping relationship.

[0105] After obtaining the image described in step S601, the computer device can perform pixel statistics on the image to obtain the pixel value of the image. The statistical method in the application scenario is the same as the statistical method in the distance measurement scenario. The statistical method may involve but is not limited to the following aspects: the image area used for statistics and the method used for counting pixels; wherein the image area used for statistics may be the entire area of ​​the image or a partial area of ​​the image; the method used for counting pixels may be an average method or a variance method.

[0106] Next, the pixel values ​​of the image described in step S601 are substituted into the first mapping relationship d=f1(P) to obtain the distance d, and based on the distance d, the distance between the observation device and the subject is obtained.

[0107] This embodiment can use the imaging module and the light source module to complete the distance measurement, and there is no need to add other dedicated distance measurement modules in the observation device, so as to ensure that the volume of the observation device meets the requirements while achieving distance measurement; and, this application determines the first mapping relationship according to the light intensity of the light source module when irradiating the object, and the angle between the optical axis of the light source module and the illuminated surface of the object when irradiating; according to the first mapping relationship and the pixel value of the image formed by the imaging module during irradiation, the distance between the observation device and the object can be obtained, without changing the pixels used for imaging in the imaging module to pixels used for distance measurement, so as to ensure the image quality while achieving distance measurement.

[0108] In one embodiment, in order to improve the ranging accuracy, the pixel values ​​of the image may include the pixel values ​​corresponding to the illuminated surface in the image; in this case, in the application scenario and the test scenario, the method of obtaining the pixel values ​​of the image may include the following steps: determining the target area corresponding to the illuminated surface from the image; performing statistical processing on the pixel values ​​of the target area to obtain the pixel values ​​corresponding to the illuminated surface in the image.

[0109] For example, when the imaging module is used to shoot the subject, the central area of ​​the lens module of the imaging module can be controlled to face the subject, and the light emitted by the light source module can be controlled to illuminate the subject; at this time, in the captured image, the central area of ​​the image can be regarded as the target area corresponding to the illuminated surface in the image. The pixel values ​​of the target area are statistically processed to obtain the pixel values ​​corresponding to the illuminated surface in the image.

[0110] If the upper left area of ​​the lens module is controlled to face the object, the upper left area of ​​the image can be regarded as the target area corresponding to the illuminated surface in the image.

[0111] In this embodiment, instead of taking the entire area of ​​the image as the image area used for statistics, the target area in the image corresponding to the illuminated surface is taken as the image area used for statistics, which can improve the ranging accuracy.

[0112] In one embodiment, the illuminated surface is a surface of a preset part of the subject, such as the wall of the digestive tract. In this case, step S603 may include: determining the distance between the observation device and the preset part according to the pixel value corresponding to the surface of the preset part in the image and the first mapping relationship.

[0113] In the case where the illuminated surface is the surface of a preset part of the subject, the distance obtained in this embodiment can be regarded as the distance between the observation device and the preset part, and the obtained distance is more precise.

[0114] The distance measurement method provided in this application involves the angle γ between the optical axis of the light source module and the illuminated surface. The calculation method of the angle γ is introduced as follows:

[0115] According to the illumination principle, the illumination at the object is inversely proportional to the square of the distance from the light source module to the object. When the angle γ between the illuminated surface of the object and the optical axis of the light source module is greater than 0, different positions on the surface of the object have different distances from the light source module. The closer to the light source module, the greater the illumination, and the greater the pixel value reflected. Figure 7 shown.

[0116] Based on this, the present application pre-constructs a mapping relationship between the ratio of bright and dark pixel values ​​and the angle γ, which is called a second-class mapping relationship. The ratio of bright and dark pixel values ​​is the ratio of the pixel values ​​between the bright area and the dark area of ​​the image. The specific ratio can be the pixel value of the bright area divided by the pixel value of the dark area, or the pixel value of the dark area divided by the pixel value of the bright area.

[0117] In the test scene of the calibration experiment, when constructing the two-type mapping relationship, the test data involved can be called the second test data. Each set of the second test data includes the ratio data of the light and dark pixel values ​​and the angle data. The ratio data of the light and dark pixel values ​​corresponds to the ratio of the pixel values ​​between the bright area and the dark area, and the angle data corresponds to the angle γ.

[0118] According to the multiple sets of second test data, two types of mapping relationships can be obtained, and the two types of mapping relationships can be referred to as second mapping relationships. Specifically, the two types of mapping relationships can be obtained by fitting based on the multiple sets of second test data, such as Figure 8 shown.

[0119] In the application scenario, before executing step S602, the computer device can determine the angle γ in the application scenario, specifically including the following steps: determining the bright area and the dark area of ​​the image; and obtaining the angle according to the ratio of the pixel values ​​between the bright area and the dark area.

[0120] In this embodiment, after obtaining the image described in step S601, the computer device can determine the bright area and the dark area of ​​the image, and calculate the ratio of the pixel values ​​between the bright area and the dark area, and obtain the angle γ in the application scenario based on the ratio of the pixel values ​​and a pre-constructed second mapping relationship.

[0121] As an optional embodiment of the present application, in test scenarios and application scenarios, when determining the bright area and dark area of ​​an image, the following steps may be specifically included: dividing the image into regions along N directions to determine N area groups; wherein the N directions are associated one-to-one with the N area groups; each area group includes two areas located on both sides of the associated direction; the N directions are different; obtaining the intra-group area pixel difference of each of the N area groups, and determining the bright area and the dark area based on the area group with the largest intra-group area pixel difference.

[0122] N can be any integer greater than or equal to 2. The N directions are different, and the present application does not limit whether the directions in the N directions are perpendicular to each other. In order to more accurately determine the bright area and the dark area, the N directions can include two directions perpendicular to each other, and the two directions perpendicular to each other can be called a direction pair, and the N directions can include one or more direction pairs.

[0123] When determining N different directions, the positive direction of a coordinate axis of the image coordinate system can be used as a reference to determine lines that form different angles with the positive direction of the coordinate axis, thereby obtaining N directions. For example, the positive direction of the x-axis of the image coordinate system can be used as a reference, and the line that forms a 0° angle with the positive direction of the x-axis can be used as a direction, the line that forms a 15° angle with the positive direction of the x-axis can be used as a direction, the line that forms a 45° angle with the positive direction of the x-axis can be used as a direction, the line that forms a 90° angle with the positive direction of the x-axis can be used as a direction, and the line that forms a 135° angle with the positive direction of the x-axis can be used as a direction, thereby obtaining 5 directions.

[0124] By dividing the image into regions along a certain direction, two regions can be obtained. The two regions are located on both sides of the image along the direction. The two regions can be considered to belong to the same region group, and the region group is associated with the direction. Therefore, by dividing the image into regions along N directions, N region groups associated one-to-one with the N directions can be obtained.

[0125] For example, when N is 2, the image is divided into regions along a first direction and a second direction perpendicular to each other.

[0126] The image is divided into regions along a first direction, thereby obtaining a region group associated with the first direction. The two regions included in the region group are called the first region and the second region. If the first direction is obtained based on a line that forms an angle of 0° with the positive direction of the x-axis, then the first direction is the x-axis, see FIG9(a), and the first region and the second region are located on both sides of the image along the x-axis direction.

[0127] The image is divided into regions along the second direction, thereby obtaining a region group associated with the second direction. The two regions included in the region group can be called the third region and the fourth region. If the second direction is based on forming a 90° angle with the positive direction of the x-axis, the second direction is the y-axis, see FIG. 9(b), and the third region and the fourth region are located on both sides of the image along the y-axis direction.

[0128] In another exemplary embodiment, when N is 4, the image is divided into regions along the first direction and the second direction perpendicular to each other, and the third direction and the fourth direction perpendicular to each other. For example:

[0129] The image is divided into regions along the third direction, thereby obtaining a region group associated with the third direction. The two regions included in the region group can be called the fifth region and the sixth region. If the third direction is based on forming a 45° angle with the positive direction of the x-axis, see FIG9(c), the fifth region and the sixth region are located on both sides of the third direction on the image.

[0130] The image is divided into regions along the fourth direction, thereby obtaining a region group associated with the fourth direction. The two regions included in the region group can be called the seventh region and the eighth region. If the fourth direction is based on forming an angle of 135° with the positive direction of the x-axis, see FIG. 9( d ), the seventh region and the eighth region are located on both sides of the image along the fourth direction.

[0131] After obtaining N area groups, the pixel value difference between two areas in the same area group may be calculated to obtain the pixel difference of the area within the area group.

[0132] Exemplarily, when N is 2, if the image is divided into regions along the first direction and the second direction, a region group associated with the first direction and a region group associated with the second direction may be obtained.

[0133] The two regions included in the region group associated with the first direction are respectively called the first region and the second region. According to the pixel value difference between the first region and the second region, the intra-region pixel difference of the region group associated with the first direction can be obtained.

[0134] The two regions included in the region group associated with the second direction are respectively called the third region and the fourth region. According to the pixel value difference between the third region and the fourth region, the intra-region pixel difference of the region group associated with the second direction can be obtained.

[0135] As another example, when N is 4, if the image is divided into regions along the first direction, the second direction, the third direction, and the fourth direction, a region group associated with the first direction, a region group associated with the second direction, a region group associated with the third direction, and a region group associated with the fourth direction can be obtained.

[0136] The manner of obtaining the intra-group pixel difference of the area group associated with the first direction and the intra-group pixel difference of the area group associated with the second direction may refer to the above example.

[0137] The two regions included in the region group associated with the third direction are respectively called the fifth region and the sixth region. According to the pixel value difference between the fifth region and the sixth region, the intra-region pixel difference of the region group associated with the third direction can be obtained.

[0138] The two regions included in the region group associated with the fourth direction are respectively called the seventh region and the eighth region. The pixel difference within the region of the region group associated with the fourth direction is obtained according to the pixel value difference between the seventh region and the eighth region.

[0139] When calculating the intra-region pixel difference of each region group, the same calculation method can be used; taking the calculation of the intra-region pixel difference of the region group associated with the first direction as an example, a feasible calculation method is introduced:

[0140] Method 1: The difference between the pixel value of the first area and the pixel value of the second area can be calculated, and the pixel value difference between the two areas can be obtained based on the difference, thereby obtaining the pixel difference within the area group; more specifically, the absolute value of the difference can be taken, and the absolute value of the difference can be used as the pixel value difference between the two areas, thereby obtaining the pixel difference within the area group.

[0141] Method 2: The ratio between the pixel value of the first area and the pixel value of the second area can be calculated, and the pixel value difference between the two areas can be obtained based on the ratio, thereby obtaining the intra-group pixel difference of the area group; more specifically, the pixel value of the first area can be divided by the pixel value of the second area, and the pixel value of the second area can be divided by the pixel value of the first area, thereby obtaining two ratios, and of the two ratios, the larger ratio is selected as the pixel value difference between the two areas, thereby obtaining the intra-group pixel difference of the area group.

[0142] After obtaining the intra-group pixel differences of N area groups, an area group with a large intra-group pixel difference can be determined, and the two areas included in the area group are used as a bright area and a dark area. Specifically, the two areas included in the area group can be called two pending areas, and in the two pending areas, the area with a large pixel value is used as a bright area, and the area with a small pixel value is used as a dark area.

[0143] It should be understood that, although the various steps in the flowcharts involved in the above-mentioned embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments can include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0144] In one embodiment, Fig.10 As shown, a distance measuring device is provided, comprising:

[0145] An image acquisition unit 1001 is used to acquire an image formed by the imaging module when the light source module illuminates the subject;

[0146] A mapping relationship determining unit 1002, configured to determine a first mapping relationship according to the light intensity of the light source module during illumination and the angle between the optical axis of the light source module and the illuminated surface of the object;

[0147] The distance acquisition unit 1003 is used to determine the distance between the observation device provided with the imaging module and the photographed object according to the pixel value of the image and the first mapping relationship.

[0148] In one embodiment, the mapping relationship determination unit 1002 is also used to select a type of mapping relationship as the first mapping relationship from a plurality of pre-constructed type-one mapping relationships based on the light intensity of the light source module during illumination and the angle between the optical axis of the light source module and the illuminated surface of the subject; wherein each of the type-one mapping relationships is associated with a mapping parameter; each group of the mapping parameters includes angle data and light intensity data, and the angle data and light intensity data included in different mapping parameters are not completely the same; the type-one mapping relationship is obtained by a plurality of groups of first test data corresponding to the mapping parameters associated with the type-one mapping relationship itself; each group of the first test data includes pixel values ​​and distances.

[0149] In one embodiment, the device further includes an angle determination unit for determining a bright area and a dark area of ​​the image; and obtaining an angle between an optical axis of the light source module and the illuminated surface based on a ratio of pixel values ​​between the bright area and the dark area.

[0150] In one embodiment, the angle determination unit is further used to divide the image into regions along N directions to determine N region groups; wherein the N directions are associated one-to-one with the N region groups; each region group includes two regions located on both sides of the associated direction; the N directions are different; and the intra-region pixel difference of each of the N region groups is obtained, and the bright region and the dark region are determined according to the region group having the largest intra-region pixel difference.

[0151] In one embodiment, when N is 2, the angle determination unit is further used to divide the image into regions along a first direction and a second direction perpendicular to each other to obtain two region groups; the region group associated with the first direction includes a first region and a second region, and the first region and the second region are located on both sides of the first direction; the region group associated with the second direction includes a third region and a fourth region, and the third region and the fourth region are located on both sides of the second direction; according to the pixel value difference between the first region and the second region, the intra-group pixel difference of the region group associated with the first direction is obtained; according to the pixel value difference between the third region and the fourth region, the intra-group pixel difference of the region group associated with the second direction is obtained.

[0152] In one embodiment, when N is 4, the angle determination unit is further used to divide the image into regions along a first direction and a second direction perpendicular to each other, and along a third direction and a fourth direction perpendicular to each other, to obtain four region groups; the region group associated with the first direction includes a first region and a second region, and the first region and the second region are located on both sides of the first direction; the region group associated with the second direction includes a third region and a fourth region, and the third region and the fourth region are located on both sides of the second direction; the region group associated with the third direction includes a fifth region and a sixth region, and the fifth region and the sixth region are located on both sides of the third direction; the region group associated with the fourth direction includes a fifth region and a sixth region, and the fifth region and the sixth region are located on both sides of the third direction; The domain group includes a seventh region and an eighth region, and the seventh region and the eighth region are located on both sides of the fourth direction; according to the difference in pixel values ​​between the first region and the second region, the difference in pixel values ​​within the region of the region group associated with the first direction is obtained; according to the difference in pixel values ​​between the third region and the fourth region, the difference in pixel values ​​within the region of the region group associated with the second direction is obtained; according to the difference in pixel values ​​between the fifth region and the sixth region, the difference in pixel values ​​within the region of the region group associated with the third direction is obtained; according to the difference in pixel values ​​between the seventh region and the eighth region, the difference in pixel values ​​within the region of the region group associated with the fourth direction is obtained.

[0153] In one embodiment, the angle determination unit is also used to obtain the angle between the optical axis of the light source module and the illuminated surface based on the ratio of pixel values ​​between the bright area and the dark area, and a second mapping relationship; the second mapping relationship is obtained based on multiple groups of second test data; each group of the second test data contains light and dark pixel value ratio data and angle data.

[0154] In one embodiment, the pixel values ​​of the image include pixel values ​​corresponding to the illuminated surface in the image; the device also includes a pixel value acquisition unit, which is used to determine the target area corresponding to the illuminated surface from the image; and statistically process the pixel values ​​of the target area to obtain the pixel values ​​corresponding to the illuminated surface in the image.

[0155] In one embodiment, the illuminated surface is the surface of a preset part of the subject; the distance acquisition unit 1003 is also used to determine the distance between the observation device and the preset part based on the pixel value corresponding to the surface of the preset part in the image and the first mapping relationship.

[0156] For the specific definition of the distance measuring device, please refer to the definition of the distance measuring method above, which will not be repeated here. Each module in the above-mentioned distance measuring device can be implemented in whole or in part by software, hardware and a combination thereof. Each of the above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory in the computer device in the form of software, so that the processor can call and execute the operations corresponding to each of the above modules.

[0157] In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps in the above-mentioned method embodiments when executing the computer program. The internal structure diagram of the computer device can be as follows: Fig.11 As shown. The computer device includes a processor, a memory and a network interface connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store ranging data. The network interface of the computer device is used to communicate with an external terminal through a network connection. The computer device also includes an input and output interface, which is a connection circuit for exchanging information between the processor and the external device. They are connected to the processor through a bus, referred to as an I / O interface. When the computer program is executed by the processor, a ranging method is implemented.

[0158] Those skilled in the art will understand that Fig.11 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0159] In one embodiment, an endoscope system is provided. The endoscope system includes an endoscope, a light source generator, a display, and the computer device described in the above embodiment.

[0160] The endoscope may include an imaging module and a light guide component of a light source module. The computer device may be provided with a distance measurement module, and the computer device may include a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps in the above-mentioned various method embodiments when executing the computer program.

[0161] Reference Fig.12 , Fig.12 A schematic diagram of the composition of an endoscope system; Fig.12Component 1201 may be a computer device, which may be provided with a distance measurement module, component 1202 may be provided with a light source generator, and component 1203 may be provided with a light guide component and an imaging module.

[0162] The imaging module includes a lens module. In one embodiment, the optical axis of the light guide component is parallel to the optical axis of the lens module, so that the light guide component is as close to the lens module as possible to improve the ranging accuracy.

[0163] Reference Fig.13 , Fig.13 Various possible arrangements between the light guide component and the lens module are shown.

[0164] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments are implemented.

[0165] In one embodiment, a computer program product is provided, on which a computer program is stored, and the computer program is used by a processor to execute the steps in the above-mentioned various method embodiments.

[0166] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the above-mentioned computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory or optical memory, etc. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0167] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0168] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A distance measurement method, characterized in that: The method comprises: Acquire an image formed by the imaging module when the light source module illuminates the subject; Determining a first mapping relationship according to the light intensity of the light source module during illumination and the angle between the optical axis of the light source module and the illuminated surface of the object; The distance between an observation device provided with the imaging module and the photographed object is determined according to the pixel value of the image and the first mapping relationship.

2. The method according to claim 1, characterized in that The determining of the first mapping relationship according to the light intensity of the light source module during illumination and the angle between the optical axis of the light source module and the illuminated surface of the object comprises: Selecting a mapping relationship of the first type as the first mapping relationship from among a plurality of pre-constructed mapping relationships of the first type according to the light intensity of the light source module during illumination and the angle between the optical axis of the light source module and the illuminated surface of the object; Among them, each of the mapping relationships of the type is associated with a mapping parameter; each group of the mapping parameters includes angle data and light intensity data, and the angle data and light intensity data included in different mapping parameters are not completely the same; the mapping relationship of the type is obtained by multiple groups of first test data corresponding to the mapping parameters associated with the mapping relationship of the type itself; each group of the first test data includes pixel values ​​and distances.

3. The method according to claim 1, characterized in that Before determining the first mapping relationship according to the light intensity of the light source module during illumination and the angle between the optical axis of the light source module and the illuminated surface of the subject, the method further includes: Determining the bright area and the dark area of ​​the image; The angle between the optical axis of the light source module and the illuminated surface is obtained according to the ratio of the pixel values ​​between the bright area and the dark area.

4. The method according to claim 3, characterized in that Determining the bright area and the dark area of ​​the image includes: The image is divided into regions along N directions to determine N region groups; wherein the N directions are associated one-to-one with the N region groups; each region group includes two regions located on both sides of the associated direction; and the N directions are different from each other; The intra-group pixel differences of the N area groups are obtained, and the bright area and the dark area are determined according to the area group having the largest intra-group pixel difference.

5. The method according to claim 4, characterized in that When N is 2, The step of dividing the image into regions along N directions to determine N region groups includes: The image is divided into regions along a first direction and a second direction perpendicular to each other to obtain two region groups; the region group associated with the first direction includes a first region and a second region, and the first region and the second region are located on both sides of the first direction; the region group associated with the second direction includes a third region and a fourth region, and the third region and the fourth region are located on both sides of the second direction; The obtaining of the pixel differences of the respective N area groups within the group includes: Obtaining a pixel difference degree of an area within a group of areas associated with the first direction according to a pixel value difference degree between the first area and the second area; According to the pixel value difference between the third area and the fourth area, the intra-group area pixel difference of the area group associated with the second direction is obtained.

6. The method according to claim 4, characterized in that When N is 4, The step of dividing the image into regions along N directions to determine N region groups includes: The image is divided into regions along a first direction and a second direction perpendicular to each other, and along a third direction and a fourth direction perpendicular to each other, to obtain four region groups; the region group associated with the first direction includes a first region and a second region, and the first region and the second region are located on both sides of the first direction; the region group associated with the second direction includes a third region and a fourth region, and the third region and the fourth region are located on both sides of the second direction; the region group associated with the third direction includes a fifth region and a sixth region, and the fifth region and the sixth region are located on both sides of the third direction; the region group associated with the fourth direction includes a seventh region and an eighth region, and the seventh region and the eighth region are located on both sides of the fourth direction; The obtaining of the pixel differences of the respective N area groups within the group includes: Obtaining a pixel difference degree of an area within a group of areas associated with the first direction according to a pixel value difference degree between the first area and the second area; Obtaining a pixel difference degree of an area within a group of areas associated with the second direction according to a pixel value difference degree between the third area and the fourth area; Obtaining a pixel difference degree of an area within a group of areas associated with the third direction according to a pixel value difference degree between the fifth area and the sixth area; According to the pixel value difference between the seventh region and the eighth region, the intra-region pixel difference of the region group associated with the fourth direction is obtained.

7. The method according to claim 3, characterized in that The step of obtaining the angle between the optical axis of the light source module and the illuminated surface according to the ratio of the pixel values ​​between the bright area and the dark area comprises: According to the ratio of pixel values ​​between the bright area and the dark area, and the second mapping relationship, the angle between the optical axis of the light source module and the illuminated surface is obtained; the second mapping relationship is obtained based on multiple groups of second test data; each group of the second test data contains bright and dark pixel value ratio data and angle data.

8. The method according to any one of claims 1 to 7, characterized in that: The pixel values ​​of the image include pixel values ​​corresponding to the illuminated surface in the image; Before determining the distance between the observation device and the photographed object according to the pixel value of the image and the first mapping relationship, the method further includes: Determining a target area corresponding to the illuminated surface from the image; Statistical processing is performed on the pixel values ​​of the target area to obtain pixel values ​​corresponding to the illuminated surface in the image.

9. The method according to any one of claims 1 to 7, characterized in that: The illuminated surface is a surface of a preset part of the photographed object; Determining the distance between the observation device and the photographed object according to the pixel value of the image and the first mapping relationship includes: The distance between the observation device and the preset part is determined according to the pixel value corresponding to the surface of the preset part in the image and the first mapping relationship.

10. A distance measuring device, characterized in that: The device comprises: An image acquisition unit, used to acquire an image formed by the imaging module when the light source module illuminates the subject; A mapping relationship determining unit, configured to determine a first mapping relationship according to the light intensity of the light source module during illumination and an angle between the optical axis of the light source module and the illuminated surface of the object; A distance acquisition unit is used to determine the distance between an observation device provided with the imaging module and the photographed object according to the pixel value of the image and the first mapping relationship.

11. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the method according to any one of claims 1 to 9 is implemented.

12. An endoscope system, characterized in that: The endoscope system comprises an endoscope, a light source generator, a display and the computer device according to claim 11; the endoscope is provided with a light guiding component of the imaging module and the light source module.

13. The endoscope system according to claim 12, characterized in that: The optical axis of the light guide component is parallel to the optical axis of the lens module of the imaging module.

Images