WO2021114886A1 - Iris image acquisition method and device and focusing method and device - Google Patents

Abstract

An iris image acquisition method and device and a focusing method and device. The iris image acquisition method comprises: firstly, on the basis of eye features in a target object image, calculating an object distance corresponding to the target object image (S102); then, according to a corresponding relation between object distance sections and focusing positions of an image acquisition module constructed on the basis of iris image acquisition indexes in advance, determining a focusing position corresponding to an object distance section to which the object distance belongs (S104); and finally according to the focusing position, focusing the image acquisition module, and acquiring an iris image by means of the focused image acquisition module (S106).

Description

Iris image acquisition method and device, focusing method and device Technical field

The embodiments of this specification relate to the field of payment technology, in particular to an iris image acquisition method, an iris image acquisition device, a focusing method and device, two computing devices, and two computer-readable storage media.

Background technique

With the gradual maturity of pattern recognition technology, biometric identification of biological individuals based on biological signs has begun to be applied and promoted in the field of identity recognition, such as mobile phone unlocking based on fingerprint recognition or face recognition, fingerprint door locks, and facial payment. Many payment platforms have introduced quick payment methods such as facial recognition payment based on facial recognition, but facial recognition is difficult to distinguish people with similar facial features, and facial features are greatly affected by external features, such as makeup and age. The change of the iris has changed significantly, and it is easy to be attacked after being reproduced by 3D printing and other means. In contrast, the identifiability, stability and resistance of iris features are better than face recognition, but due to the larger size of the iris Small, making the acquisition of clear iris images become one of the main bottlenecks in the further promotion and application of iris recognition.

Summary of the invention

In view of this, the embodiment of this specification provides an iris image acquisition method. One or more embodiments of this specification provide an iris image acquisition device, a focusing method and device, two computing devices, and two computer-readable storage media at the same time.

An embodiment of this specification provides an iris image acquisition method, including: calculating the object distance corresponding to the target object image based on the eye features in the target object image; the target object image is collected by the image acquisition module; The corresponding relationship between the object distance interval and the focusing position of the image acquisition module constructed by the image acquisition index is determined, and the focusing position corresponding to the object distance interval to which the object distance belongs is determined; The subsequent image acquisition module acquires iris images.

Optionally, the corresponding relationship between the object distance interval and the focus position is constructed in the following manner: according to the image parameter corresponding to the iris image acquisition index, at least one image parameter is used as the target parameter, and the target parameter is determined according to the iris image acquisition index. The target constraint conditions corresponding to the target parameters, and the fixed constraint conditions corresponding to the remaining image parameters are determined according to the iris image acquisition index; for each target parameter, an image acquisition module is established under the constraints of the fixed constraint conditions. The relationship curve between the object distance and the target parameter at the focus position; based on the relationship curve, the minimum object distance and the maximum object distance that the image acquisition module meets the target constraint conditions at each focus position are determined, and the minimum object distance and The maximum object distance constitutes an object distance interval; the corresponding relationship between the object distance interval and the focus position is generated by constructing the correspondence relationship between the object distance interval and the focus position of the image acquisition module.

Optionally, the calculation of the object distance corresponding to the target object image based on the eye features is implemented by calling a depth sensing sub-module configured by the image acquisition module, wherein the depth sensing sub-module collects The depth data calculates the actual collection distance between the eye of the target object corresponding to the target object image and the image collection module, and outputs the calculated actual collection distance as the object distance.

Optionally, after the step of calculating the object distance corresponding to the target object image based on the eye characteristics in the case of detecting eye features in the target object image collected by the image acquisition module is performed, and the The corresponding relationship between the object distance interval and the focus position of the image acquisition module constructed based on the iris image acquisition index, and before the step of determining the focus position corresponding to the object distance interval to which the object distance belongs, includes: the object distance interval corresponds to the focus position In the relationship, find whether there is an object distance interval to which the object distance belongs; if so, execute the corresponding relationship between the object distance interval and the focus position of the image acquisition module constructed based on the iris image acquisition index in advance, and determine the object distance to which the object distance belongs. The focus position step corresponding to the object distance interval; if it does not exist, the target object image is collected by the image acquisition module and the eye feature detection is performed.

Optionally, the focusing of the image acquisition module according to the focus position includes: issuing a focus instruction to a focus control sub-module configured by the image acquisition module, and the focus control sub-module is based on the focus The focus position carried in the instruction adjusts the lens group configured by the image acquisition module to the focus position.

The embodiment of this specification also provides an iris image acquisition device, including: a processing module and an image acquisition module; wherein the processing module is configured to calculate the object corresponding to the target object image based on the eye features in the target object image. Distance, and according to the corresponding relationship between the object distance interval and the focus position of the image acquisition module constructed in advance based on the iris image acquisition index, determine the focus position corresponding to the object distance interval to which the object distance belongs, and send it to the image acquisition module to carry There is a focus instruction for the focus position; the target object image is collected by the image acquisition module; the image acquisition module is configured to collect the target object image, and according to the focus issued by the processing module The focus position carried by the instruction is to focus, and an iris image is collected after focus.

Optionally, the corresponding relationship between the object distance interval and the focus position is constructed in the following manner: according to the image parameter corresponding to the iris image acquisition index, at least one image parameter is used as the target parameter, and the target parameter is determined according to the iris image acquisition index. The target constraint conditions corresponding to the target parameters, and the fixed constraint conditions corresponding to the remaining image parameters are determined according to the iris image acquisition index; for each target parameter, an image acquisition module is established under the constraints of the fixed constraint conditions. The relationship curve between the object distance and the target parameter at the focus position; based on the relationship curve, the minimum object distance and the maximum object distance that the image acquisition module meets the target constraint conditions at each focus position are determined, and the minimum object distance and The maximum object distance constitutes an object distance interval; the corresponding relationship between the object distance interval and the focus position is generated by constructing the correspondence relationship between the object distance interval and the focus position of the image acquisition module.

Optionally, the image acquisition module is configured with a depth sensing sub-module, wherein the depth sensing sub-module calculates the difference between the eye of the target object corresponding to the target object image and the image acquisition module by collecting depth data The actual collection distance between the two, and the calculated actual collection distance is output as the object distance.

Optionally, the image acquisition module includes: a focus control sub-module, a lens group, and a photosensitive component; wherein the focus control sub-module is configured to receive the focus instruction carrying the focus position issued by the processing module , And adjust the lens group to the focus position according to the focus instruction.

The embodiment of the present specification also provides a focusing method, including: determining the object distance corresponding to the target object image collected by the image acquisition module; according to the corresponding relationship between the object distance interval and the focus position constructed based on the image acquisition parameters of the image acquisition module in advance , Determine the focus position corresponding to the object distance interval to which the object distance belongs; focus the image acquisition module according to the focus position.

Optionally, the corresponding relationship between the object distance interval and the focus position is constructed in the following manner: at least one of the image acquisition parameters is used as a target parameter, and the remaining image acquisition parameters are determined as constraint parameters; Parameters, in combination with the constraint parameters, the relationship curve between the object distance and the target parameter at each focus position of the image acquisition module is established; based on the relationship curve, it is determined that the image acquisition module satisfies the target parameter at each focus position The minimum object distance and the maximum object distance of the corresponding parameter threshold, and the object distance interval is composed of the minimum object distance and the maximum object distance; by constructing the correspondence between the object distance interval and the focus position of the image acquisition module , Generating the corresponding relationship between the object distance interval and the focus position.

Optionally, the step of determining the object distance corresponding to the target object image collected by the image acquisition module is implemented by calling a depth sensing sub-module configured by the image acquisition module, wherein the depth sensing sub-module is The data calculates the actual collection distance between the target object corresponding to the target object image and the image collection module, and outputs the calculated actual collection distance as the object distance.

Optionally, after the step of determining the object distance corresponding to the target object image collected by the image acquisition module is performed, and the corresponding relationship between the object distance interval and the focus position constructed based on the image acquisition parameters of the image acquisition module in advance, Before the step of determining the focus position corresponding to the object distance interval to which the object distance belongs is executed, the step includes: searching for the object distance interval to which the object distance belongs in the corresponding relationship between the object distance interval and the focus position; The corresponding relationship between the object distance interval and the focus position constructed based on the image acquisition parameters of the image acquisition module in advance, and the step of determining the focus position corresponding to the object distance interval to which the object distance belongs; if it does not exist, collect the target through the image acquisition module Object image, and return to execute the step of determining the object distance corresponding to the target object image collected by the image collection module.

Optionally, the focusing of the image acquisition module according to the focus position includes: issuing a focus instruction to a focus control sub-module configured by the image acquisition module, and the focus control sub-module is based on the focus The focus position carried in the instruction adjusts the lens group configured by the image acquisition module to the focus position.

The embodiment of this specification also provides a focusing device, including: a processing module and an image acquisition module; wherein the processing module is configured to determine the object distance corresponding to the target object image collected by the image acquisition module, And according to the corresponding relationship between the object distance interval and the focus position constructed based on the image acquisition parameters of the image acquisition module in advance, the focus position corresponding to the object distance interval to which the object distance belongs is determined, and issued to the image acquisition module with The focus instruction of the focus position; the image acquisition module is configured to collect the target object image, and focus according to the focus position carried in the focus instruction issued by the processing module.

The embodiments of this specification also provide a computing device, including: a memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions: based on the eye in the target object image The feature calculates the object distance corresponding to the target object image; the target object image is collected by the image acquisition module; the object distance is determined according to the corresponding relationship between the object distance interval and the focus position of the image acquisition module constructed based on the iris image acquisition index The focusing position corresponding to the object distance interval to which it belongs; focusing on the image acquisition module according to the focusing position, and acquiring an iris image through the focused image acquisition module.

The embodiment of this specification also provides a computing device, including: a memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions: determine the target collected by the image acquisition module The object distance corresponding to the object image; determine the focus position corresponding to the object distance interval to which the object distance belongs according to the corresponding relationship between the object distance interval and the focus position constructed based on the image acquisition parameters of the image acquisition module in advance; according to the focus position Focusing on the image acquisition module.

The embodiment of this specification also provides a computer-readable storage medium, which stores computer instructions, which implement the steps of the iris image acquisition method when the instructions are executed by a processor.

The embodiments of this specification also provide a computer-readable storage medium that stores computer instructions, which implement the steps of the focusing method when the instructions are executed by a processor.

An embodiment of this specification determines the object distance interval to which the image acquisition module performs iris image acquisition by calculating the object distance between the target object corresponding to the target object image and the image acquisition module, and collects the image according to the correspondence between the object distance interval and the focus position The module matches the adapted focus position, and finally collects the iris image after adjusting the focus of the image acquisition module according to the focus position, which improves the focusing efficiency of the image acquisition module in the iris image acquisition process, and at the same time avoids the problem of the image acquisition module. Acquire high-quality iris images for frequent focusing, thereby prolonging the service life of the image acquisition module.

Another embodiment of this specification calculates the object distance between the target object corresponding to the target object image collected by the image acquisition module and the image acquisition module, and determines the object distance interval to which the object distance belongs according to the correspondence between the object distance interval and the focus position Determine the suitable focus position for the image acquisition module, and finally adjust the focus of the image acquisition module according to the focus position, which improves the focusing efficiency of the image acquisition module and avoids frequent focusing adjustments of the image acquisition module during the focusing process. Extend the service life of the image acquisition module.

Description of the drawings

FIG. 1 is a processing flowchart of an iris image acquisition method provided by an embodiment of this specification;

FIG. 2 is a graph showing the variation curve of the modulation degree of the user's eye image relative to the object distance according to the first embodiment of this specification;

FIG. 3 is a graph showing the change of the modulation degree of the user's eye image relative to the object distance according to the embodiment of the present specification;

Fig. 4 is a schematic diagram of an iris image acquisition device provided by an embodiment of this specification;

FIG. 5 is a processing flowchart of a focusing method provided by an embodiment of this specification;

FIG. 6 is a schematic diagram of a focusing device provided by an embodiment of this specification;

FIG. 7 is a structural block diagram of a computing device provided by an embodiment of this specification;

Fig. 8 is a structural block diagram of another computing device provided by an embodiment of this specification.

Detailed ways

In the following description, many specific details are explained in order to fully understand this specification. However, this specification can be implemented in many other ways different from those described here, and those skilled in the art can make similar extensions without departing from the connotation of this specification. Therefore, this specification is not limited by the specific implementation disclosed below.

The terms used in one or more embodiments of this specification are only for the purpose of describing specific embodiments, and are not intended to limit one or more embodiments of this specification. The singular forms of "a", "said" and "the" used in one or more embodiments of this specification and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings. It should also be understood that the term "and/or" used in one or more embodiments of this specification refers to and includes any or all possible combinations of one or more associated listed items.

It should be understood that although the terms first, second, etc. may be used to describe various information in one or more embodiments of this specification, the information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of one or more embodiments of this specification, the first may also be referred to as the second, and similarly, the second may also be referred to as the first. Depending on the context, the word "if" as used herein can be interpreted as "when" or "when" or "in response to determination".

First, the terminology involved in one or more embodiments of the present invention will be explained.

Iris: The iris is a circular area between the pupil (black) and the sclera (white) of the human eye. It can capture rich texture information under infrared light. It is a unique feature of an individual and can be used for individual identification.

Focus (Focus): by adjusting the distance between the lens group and the photosensitive element, changing the imaging focus position so that the object image falls on the photosensitive element, the process of forming a clear image.

Spatial Resolution: It is used to characterize the detailed resolution capability of the camera system, usually expressed by the number of resolvable black and white line pairs per unit length (eg, line pairs/mm).

One embodiment of this specification provides an iris image acquisition method, and one or more embodiments of this specification also provide an iris image acquisition device, a focusing method and device, two computing devices, and two computer-readable storage media. The following is a detailed description one by one in conjunction with the accompanying drawings of the embodiments provided in this specification, and each step of the method is described.

An example of an iris image acquisition method provided in this specification is as follows.

Referring to FIG. 1, it shows a processing flowchart of an iris image acquisition method provided by an embodiment of this specification, and referring to FIG. 2, which shows the modulation degree of the first eye image of a user provided by the embodiment of this specification. With respect to the variation curve of the object distance, refer to FIG. 3, which shows the variation curve of the modulation degree of the user's eye image with respect to the object distance according to the embodiment of the present specification.

Step S102: Calculate the object distance corresponding to the target object image based on the eye features in the target object image.

In practical applications, an important part of iris recognition is how to collect iris images quickly and accurately. In the process of iris image collection, because the iris recognition algorithm requires high iris image quality, it is necessary to repeatedly adjust the image distance of the image collection module to The iris image collected by the image acquisition module meets the requirements. The iris image acquisition based on this is not only low in efficiency, but also repeated focusing during the iris image acquisition process will increase the loss of the image acquisition module and reduce the service life of the image acquisition module.

In the iris image acquisition method provided in this embodiment, the image distance of the image acquisition module is divided into multiple focus segments before the iris image acquisition, and the actual working range of the image acquisition module for iris image acquisition (the effective acquisition of iris image The span from the shortest distance to the farthest distance) is divided into multiple working intervals, so that the working interval of the image acquisition module for iris image acquisition is corresponding to the focus segment. Based on this, the image acquisition module performs the iris image acquisition process. On the basis of image recognition, the actual acquisition distance (object distance) between the captured target object and the image acquisition module is calculated. According to the working interval to which the object distance belongs, the image acquisition module is finally focused according to the focus segment corresponding to the working interval to which the object distance belongs. , And perform iris image acquisition after the focus is completed, which improves the focusing efficiency of the image acquisition module in the iris image acquisition process, and at the same time avoids the image acquisition module from frequently focusing on the acquisition of high-quality iris images, thereby extending the image acquisition module’s Service life.

The image acquisition module described in this embodiment refers to an image acquisition component configured with a lens group and a photosensitive component for image acquisition, and the distance (image distance) between the lens group and the photosensitive component can be performed according to actual iris image acquisition requirements Focus adjustment. For example, an image collection component configured in a payment terminal in an offline store, or an image collection component configured in a mobile terminal such as a mobile phone, uses the iris image collected by the image collection component for identity recognition during the payment process.

In specific implementation, first collect the target object image of the target object (for example, the payment user who recognizes the identity through iris recognition during the payment process of the offline store) through the image acquisition module; and then perform the eye image in the collected target object image Feature detection. In the case that eye features are detected in the target object image, the actual collection distance between the target object and the image collection camera is calculated based on the detected eye features, that is, the image collection module is collecting The object distance when the target object is imaged.

In order to make the calculation of the object distance corresponding to the target object image more accurate, in an optional implementation manner provided in this embodiment, the calculation is performed by calling the depth sensing sub-module configured by the image acquisition module. Specifically, the depth The sensing sub-module collects the depth data between the target object and the image acquisition module when the image acquisition module collects the image of the target object (for example, through the 3D structured light or ToF (Time of Flight) module to collect the payment user and the image acquisition component). After the depth data between the target object and the image acquisition module is collected, the actual acquisition distance between the eye of the target object corresponding to the target object image and the image acquisition module is calculated according to the acquired depth data , And output the calculated actual collection distance as the object distance.

It should be noted that in the process of detecting eye features in the target object image, in order to improve the efficiency and accuracy of feature detection, a deep learning method is used to perform eye feature detection, specifically by training an eye feature detection model, The target object image is input to the trained eye feature detection model for eye feature detection, and the position information of the detected eye feature in the target object image is output, so that the eye detected by the eye feature detection model More accurate object distance calculations are carried out on the basis of some features.

In addition, in specific implementation, in order to improve the smoothness of the image acquisition module in the iris image acquisition process and enhance the user’s acquisition experience, in an optional implementation manner proposed in this embodiment, the target object image is calculated as described above. On the basis of the corresponding object distance, searching for whether there is an object distance interval to which the object distance belongs in the corresponding relationship between the object distance interval and the focus position;

If it exists, perform the following step S104, and determine the focus position corresponding to the object distance interval to which the object distance belongs according to the corresponding relationship between the object distance interval and the focus position of the image acquisition module constructed based on the iris image acquisition index in advance;

If it does not exist, it means that the focus position of the image acquisition module cannot be determined by the corresponding relationship between the object distance interval and the focus position. The image acquisition module collects the target object image again and performs eye feature detection. When the eye feature is detected in the image, return to step S102 to complete the iris image acquisition process of the image acquisition module.

Step S104: Determine the focus position corresponding to the object distance interval to which the object distance belongs according to the correspondence between the object distance interval and the focus position of the image acquisition module constructed in advance based on the iris image acquisition index.

In this embodiment, the purpose of collecting the iris image is to perform identity recognition based on the iris image, and in the process of identity recognition in actual applications, there are certain requirements for the image index of the iris image, and only the iris image that meets certain index requirements is required. Can realize the identity recognition based on iris image. The iris image collection index in this embodiment refers to the quality or feature requirements of the iris image when performing identity recognition based on the iris image. For example, the iris recognition algorithm or the iris recognition system requires the input iris image to have a spatial resolution of At 2lp/mm, the modulation degree (MTF, Modulation Transfer Function) is not less than 60%.

The object distance interval in this embodiment refers to the actual working range of the image acquisition module for iris image acquisition (that is, the span range from the shortest distance to the farthest distance for effectively acquiring the iris image) divided into the distance interval. For example, the shortest distance of the image acquisition component configured in the payment terminal of the offline store to effectively collect the user's iris image is 300mm, and the farthest distance is 750mm, then the actual working range of the image acquisition component is 300mm～750mm. The span range is divided into several sub-intervals, which is the object distance interval.

In this embodiment, the image capture module includes a lens group and a photosensitive component, and the image distance adjustment during the focusing process of the image capture module is realized by adjusting the position of the lens group, and the lens group relative to the photosensitive component is adjusted by adjusting the position of the lens group. In order to achieve focusing through the image distance adjustment of the image acquisition module. The focus position refers to the specific position of the lens group in the image acquisition module. The lens group is in different focus positions, the distance between the lens group and the photosensitive component is different, and the image distance of the image acquisition module is also different.

In this embodiment, in order to improve the focusing efficiency of the image acquisition module in the iris image acquisition process, avoid the image acquisition module from frequently performing focusing adjustments for acquiring high-quality iris images, and prolong the service life of the image acquisition module, the method of "focusing in stages" is adopted. Focusing on the image acquisition module, and the realization of "stage focusing" depends on the pre-built correspondence between the object distance and the focusing section of the image acquisition module, that is, the correspondence between the object distance section and the focus position, which is provided in this embodiment In an optional implementation manner, the corresponding relationship between the object distance interval and the focus position is constructed in the following manner:

1) According to the image parameter corresponding to the iris image acquisition index, at least one image parameter is used as a target parameter, and the target constraint condition corresponding to the target parameter is determined according to the iris image acquisition index, and determined according to the iris image acquisition index The fixed constraint conditions corresponding to the remaining image parameters;

2) For each target parameter, the relationship curve between the object distance and the target parameter at each focus position of the image acquisition module is established under the constraints of the fixed constraint conditions;

3) Determine, based on the relationship curve, the minimum object distance and the maximum object distance that the image acquisition module satisfies the target constraint condition at each focus position, and an object distance interval is composed of the minimum object distance and the maximum object distance;

4) By constructing the corresponding relationship between the object distance interval and the focus position of the image acquisition module, the corresponding relationship between the object distance interval and the focus position is generated.

For example, for the image acquisition component configured in the payment terminal in an offline store, the corresponding relationship between the object distance interval and the focus position of the image acquisition component is constructed offline in advance. After the corresponding relationship between the object distance interval and the focus position is constructed, the object distance will be constructed. The corresponding relationship between the interval and the focus position is written into the storage space of the image acquisition component for storage, so that the subsequent use of the image acquisition component for iris image acquisition can adopt a "stage focus" method for focusing.

Among them, the construction of the correspondence between the object distance interval and the focus position of the image acquisition component includes the following 4 steps a) to d).

a) When the iris image collected by the image acquisition component is identified by the iris recognition algorithm, the requirement for the iris image is: Modulation Transfer Function (MTF) is not less than 60% when the spatial resolution is 2lp/mm, There are two kinds of image parameters, namely, spatial resolution and modulation degree. The modulation degree is used as the target parameter. It can be seen that the target constraint condition corresponding to the modulation degree is that the modulation degree is not less than 60%. The remaining image parameters except for the modulation degree are Spatial resolution, the fixed constraint condition corresponding to the spatial resolution is determined to satisfy 2lp/mm.

b) When the spatial resolution is 2lp/mm, the relationship curve between the object distance and the modulation degree of the image acquisition component at each focus position is established.

As shown in Figure 2, the abscissa represents the object distance (that is, the actual collection distance between the user’s eyes and the image capture component), and the ordinate represents the modulation degree. When the object distance is 350mm, the image distance of the image capture component is v1 The imaging effect is the best when the image acquisition component is performing image acquisition, that is, the user's eye image collected by the image acquisition component happens to fall on the photosensitive element of the image acquisition component and the image is clear. The curve shown in the figure is that the spatial resolution is 2lp/mm( When the fixed constraint condition), when the image distance of the image acquisition component is v1, the modulation curve of the user's eye image relative to the object distance, as shown in the figure, the user's eye image is collected when the object distance is in the range of 300～379mm The modulation degree is greater than 60% (the modulation degree is not less than 60% to meet the target constraint condition), which meets the iris image requirements of the iris recognition algorithm.

Similarly, when the object distance is 450mm, when the image distance of the image acquisition component is v2, the imaging effect is the best. When the object distance is 550mm, the image acquisition component has the best imaging effect when the image distance is v3. When the object distance is 650mm The imaging effect is best when the image distance of the image acquisition component is v4, and when the object distance is 750mm, the imaging effect is the best when the image distance of the image acquisition component is v5, that is: the user's eye image collected by the image acquisition component during image acquisition It happens to fall on the photosensitive element of the image acquisition component and the image is clear, which is the same as that shown in Figure 2 when the spatial resolution is 2lp/mm. When the image distance of the image acquisition component is v1, the modulation degree of the user's eye image is relative to the object distance. The change curve is similar to the change curve of the user’s eye image modulation relative to the object distance when the image distance of the acquisition component is v2, v3, v4, and v5 when the spatial resolution is 2lp/mm;

As shown in Figure 3, when the spatial resolution is 2lp/mm, 301 is the variation curve of the modulation degree of the user's eye image with respect to the object distance when the image distance of the image acquisition component is v1, and 302 is the image of the image acquisition component The change curve of the modulation degree of the user's eye image relative to the object distance when the distance is v2, 303 is the change curve of the modulation degree of the user's eye image relative to the object distance when the image distance of the image acquisition component is v3, and 304 is the image acquisition component The change curve of the modulation degree of the user's eye image with respect to the object distance when the image distance of is v4, and 305 is the change curve of the modulation degree of the user's eye image with respect to the object distance when the image collection component's image distance is v5.

c) Based on the relationship curve (301 to 305), determine the minimum object distance and the maximum object distance with the modulation degree greater than 60% at each focus position of the image acquisition component (the modulation degree is not less than 60% to meet the target constraint condition), and determine the minimum object distance And the maximum object distance constitute the object distance interval.

Specifically, for the variation curve 301 of the modulation degree of the user's eye image with respect to the object distance when the image distance of the image acquisition component is v1, the minimum object distance and the maximum object distance for which the modulation degree is greater than 60%, the object distance interval is 300mm～379mm .

For the variation curve 302 of the modulation degree of the user's eye image with respect to the object distance when the image distance of the image acquisition component is v2, the minimum object distance and the maximum object distance for which the modulation degree is greater than 60% constitute the object distance interval of 380mm-479mm.

For the variation curve 303 of the modulation degree of the user's eye image relative to the object distance when the image distance of the image acquisition component is v3, the minimum object distance and the maximum object distance composed of the object distance interval of 480mm-579mm where the modulation degree is greater than 60%.

For the variation curve 304 of the modulation degree of the user's eye image with respect to the object distance when the image distance of the image acquisition component is v4, the minimum object distance and the maximum object distance composition where the modulation degree is greater than 60% are 580mm-679mm.

For the variation curve 305 of the modulation degree of the user's eye image with respect to the object distance when the image distance of the image acquisition component is v5, the minimum object distance and the maximum object distance constitute the object distance interval of 680mm-750mm when the modulation degree is greater than 60%.

d) Generate the corresponding relationship between the object distance interval and the focus position of the image acquisition component, as shown in the following table:

Object distance interval/mm	Image distance	Focus position
300mm～379mm	v1	L1
380mm～479mm	v2	L2
480mm～579mm	v3	L3
580mm～679mm	v4	L4
680mm～750mm	v5	L5

Among them, L1 is the position of the lens group when the image distance of the image acquisition component is v1, that is, the focus position corresponding to the object distance interval of 300mm to 379mm.

L2 is the position of the lens group when the image distance of the image acquisition component is v2, that is, the focus position corresponding to the object distance interval of 380mm to 479mm.

L3 is the position of the lens group when the image distance of the image acquisition component is v3, that is, the focus position corresponding to the object distance interval of 480mm to 579mm.

L4 is the position of the lens group when the image distance of the image acquisition component is v4, that is, the focus position corresponding to the object distance interval of 580mm to 679mm.

L5 is the position of the lens group when the image distance of the image acquisition component is v5, that is, the focus position corresponding to the object distance interval of 680mm to 750mm.

It can be seen that by dividing the object distance during iris image acquisition by the image acquisition component into 5 object distance intervals, and these 5 object distance intervals are respectively corresponding to the corresponding focus positions of the image acquisition component, and then, the image acquisition component When collecting iris images based on this, determine the object distance interval according to the actual collection distance at the time of collection, and then adjust the lens group of the image acquisition component to the focus position corresponding to the object distance interval. The image distance is adjusted to match the actual acquisition distance. On the one hand, it avoids repeatedly adjusting the focus position during the focusing process to find a focus position that matches the actual acquisition distance. On the other hand, it also avoids the image acquisition component in a focus adjustment process. The medium adjustment range is too large, thereby prolonging the service life of the image acquisition component and reducing equipment maintenance caused by frequent focus adjustment.

It should be noted that, taking the spatial resolution and modulation degree as an example, the construction process of the correspondence between the object distance interval and the focus position is described. In addition, multiple different spatial resolutions and modulation degrees (such as When the spatial resolution is 3lp/mm, the modulation degree is not less than 50%, or when the spatial resolution is 4lp/mm, the modulation degree is not less than 35%) and one or more other images based on the spatial resolution and modulation degree. Parameters (for example, resolution) construct the correspondence between the object distance interval and the focus position of the image acquisition module, or combine the spatial resolution and/or modulation with one or more other image parameters to construct the object distance interval and focus position of the image acquisition module The corresponding relationship is not limited in this embodiment. The specific construction process is similar to the construction process of the correspondence relationship between the object distance interval and the focus position based on the spatial resolution and modulation degree provided above, and will not be repeated here.

During specific implementation, on the basis of calculating the object distance corresponding to the target object image in the above step S102, determine the object distance interval to which the object distance belongs in the corresponding relationship between the object distance interval and the focus position, and further determine the object distance In the correspondence between the object distance interval and the focus position, the focus position corresponding to the object distance interval to which the object distance belongs is determined.

Following the above example, if the object distance corresponding to the user's eye image collected by the image acquisition component is calculated to be 500mm, the above table shows that the object distance corresponding to the user's eye image is in the object distance range of 480mm to 579mm. In the interval, the focus position of the lens group in the image acquisition component corresponding to the object distance interval is L3.

Step S106: Focus the image acquisition module according to the focus position, and acquire an iris image through the focused image acquisition module.

In an optional implementation manner provided by this embodiment, focusing the image acquisition module according to the focus position is specifically implemented in the following manner: issuing a focus instruction to the focus control sub-module configured by the image acquisition module, The focus control sub-module adjusts the lens group configured by the image acquisition module to the focus position according to the focus position carried in the focus instruction.

On this basis, after the focus is achieved by adjusting the position of the lens group in the image acquisition module to the focus position corresponding to the object distance, the iris image of the target object is acquired by the image acquisition module after focusing, and then in the application according to the acquisition Of the iris image for identification.

Following the above example, if the object distance corresponding to the user's eye image collected by the image capture component is calculated to be 500mm, and based on the object distance interval and the focus position correspondence table, the focus corresponding to the object distance interval 480mm ~ 579mm to which this object distance belongs is determined When the position is L3, the focus instruction is issued to the image acquisition component, and the focus instruction includes the focus position L3. After it is issued, the focus motor (such as voice coil motor, Voice Coil Motor) configured in the image acquisition component will adjust the lens group To the focus position L3, the iris image of the paying user is collected at the image distance corresponding to the focus position L3 thereafter.

In summary, in the iris image acquisition method, when eye features are detected in the target object image collected by the image acquisition module, the object distance between the target object corresponding to the target object image and the image acquisition module is calculated. Determine the object distance interval of the image acquisition module for iris image acquisition, and according to the corresponding relationship between the object distance interval and the focus position, match the image acquisition module with a suitable focus position, and finally perform focus adjustment on the image acquisition module according to the focus position. The image acquisition improves the focusing efficiency of the image acquisition module in the iris image acquisition process, and at the same time prevents the image acquisition module from frequently focusing for acquiring high-quality iris images, thereby prolonging the service life of the image acquisition module.

The embodiment of an iris image acquisition device provided in this specification is as follows: In the above-mentioned embodiment, an iris image acquisition method is provided. Correspondingly, an iris image acquisition device is also provided. The following is combined with the drawings Be explained.

Referring to FIG. 4, it shows a schematic diagram of an iris image acquisition device provided by this embodiment.

Since the device embodiment corresponds to the method embodiment, the description is relatively simple. For related parts, please refer to the corresponding description of the method embodiment provided above. The device embodiments described below are merely illustrative.

This specification provides an iris image acquisition device, including: a processing module 410, an image acquisition module 420; wherein the processing module 410 is configured to calculate the object corresponding to the target object image based on the eye features in the target object image. According to the corresponding relationship between the object distance interval and the focus position of the image acquisition module constructed in advance based on the iris image acquisition index, determine the focus position corresponding to the object distance interval to which the object distance belongs, and send it to the image acquisition module 420 Carrying the focus instruction of the focus position; the target object image is collected by the image acquisition module 420; the image acquisition module 420 is configured to collect the target object image and issue it according to the processing module 410 Focusing is performed at the focus position carried by the focus instruction, and an iris image is collected after focusing.

Optionally, the corresponding relationship between the object distance interval and the focus position is constructed in the following manner: according to the image parameter corresponding to the iris image acquisition index, at least one image parameter is used as the target parameter, and the target parameter is determined according to the iris image acquisition index. The target constraint conditions corresponding to the target parameters, and the fixed constraint conditions corresponding to the remaining image parameters are determined according to the iris image acquisition index; for each target parameter, an image acquisition module is established under the constraints of the fixed constraint conditions. The relationship curve between the object distance and the target parameter at the focus position; based on the relationship curve, the minimum object distance and the maximum object distance that the image acquisition module meets the target constraint conditions at each focus position are determined, and the minimum object distance and The maximum object distance constitutes an object distance interval; the corresponding relationship between the object distance interval and the focus position is generated by constructing the correspondence relationship between the object distance interval and the focus position of the image acquisition module.

Optionally, the image acquisition module 420 is configured with a depth sensing sub-module 421, wherein the depth sensing sub-module calculates the relationship between the eye of the target object corresponding to the target object image and the image acquisition by collecting depth data. The actual collection distance between the modules 420, and the calculated actual collection distance is output as the object distance.

Optionally, the image acquisition module 420 includes: a focus control sub-module 422, a lens group 423, and a photosensitive component 424; wherein the focus control sub-module 422 is configured to receive the focus control module 410 issued by the processing module 410 to carry the focus. Position the focus instruction, and adjust the lens group 423 to the focus position according to the focus instruction.

An embodiment of a focusing method provided in this specification is as follows: referring to FIG. 5, which shows a processing flowchart of a focusing method provided in an embodiment of this specification, the focusing method includes step S502 to step S506.

Step S502: Determine the object distance corresponding to the target object image collected by the image collection module.

In the focusing method provided by this embodiment, the image distance of the image acquisition module is divided into multiple focusing segments, and the actual working range of the image acquisition module for image acquisition (that is, the range between the closest distance to the farthest distance for effectively acquiring an image) The span range between the image acquisition module) is divided into multiple working intervals, so that the working interval of the image acquisition module for image acquisition is corresponding to the focusing section. During the focusing process, the actual acquisition distance between the captured target object and the image acquisition module is calculated ( Object distance), according to the working interval to which the object distance belongs, and finally adjust the focus of the image acquisition module according to the focus segment corresponding to the working interval to which the object distance belongs, which improves the focusing efficiency of the image acquisition module and avoids the focusing process of the image acquisition module at the same time. The focus adjustment is frequently performed in the middle, thereby prolonging the service life of the image acquisition module.

The image acquisition module in this embodiment refers to an image acquisition component configured with a lens group and a photosensitive component for image acquisition, and the distance (image distance) between the lens group and the photosensitive component can be adjusted according to the focus. For example, an image acquisition component configured in a mobile terminal such as a mobile phone.

In the specific implementation, the image acquisition module first collects the target object image of the target object (for example, a user holding a mobile terminal); and then calculates the actual acquisition distance between the target object and the image acquisition camera, that is, the image acquisition module is collecting the The object distance when the target object is imaged.

In order to make the calculation of the object distance corresponding to the target object image more accurate, in an optional implementation manner provided in this embodiment, the calculation is performed by calling the depth sensing sub-module configured by the image acquisition module. Specifically, the depth The sensing sub-module collects the depth data between the target object and the image acquisition module when the image acquisition module collects the image of the target object (for example, through 3D structured light or ToF (Time of Flight) module to collect between the user and the image acquisition component After the depth data between the target object and the image acquisition module is collected, the actual acquisition distance between the target object corresponding to the target object image and the image acquisition module is calculated according to the acquired depth data, and the actual acquisition distance is calculated The obtained actual collection distance is output as the object distance.

In addition, in specific implementation, in order to improve the fluency of the focusing process and enhance the user's experience in the focusing process, in an optional implementation manner proposed in this embodiment, the object distance corresponding to the target object image is calculated as described above. After that, search for the object distance interval to which the object distance belongs in the corresponding relationship between the object distance interval and the focus position; if so, perform the following step S504, according to the image acquisition parameters based on the image acquisition module in advance The constructed correspondence between the object distance interval and the focus position determines the focus position corresponding to the object distance interval to which the object distance belongs; The image of the target object is collected by the image collection module, and the execution of the above step S502 is returned.

Step S504: Determine the focus position corresponding to the object distance interval to which the object distance belongs based on the correspondence between the object distance interval and the focus position constructed based on the image acquisition parameters of the image acquisition module in advance.

In practical applications, the image acquisition module has certain performance indicators, and these performance indicators will eventually be reflected in the images collected by the image acquisition module. The image acquisition parameters in this embodiment refer to the image quality parameters or image characteristic parameters of the images collected by the image acquisition module, for example, the modulation degree of the image acquired by the image acquisition component configured in the mobile terminal when the spatial resolution is x1lp/mm (MTF, Modulation Transfer Function) is x2%.

The object distance interval in this embodiment refers to the distance interval after the actual working range of the image acquisition module for image acquisition (the span range from the shortest distance to the farthest distance for effectively acquiring an image) is divided. For example, if the shortest distance for the image capture component of the payment terminal configured in an offline store to effectively capture user images is D1, and the farthest distance is D2, then the actual working range of the image capture component is the span of D1～D2. The divided sub-intervals are the object distance intervals.

In this embodiment, the image capture module includes a lens group and a photosensitive component, and the image distance adjustment during the focusing process of the image capture module is realized by adjusting the position of the lens group, and the lens group relative to the photosensitive component is adjusted by adjusting the position of the lens group. In order to achieve focusing through the image distance adjustment of the image acquisition module. The focus position refers to the specific position of the lens group in the image acquisition module. The lens group is in different focus positions, the distance between the lens group and the photosensitive component is also different, and the image distance of the image acquisition module is also different.

In this embodiment, in order to improve the focusing efficiency of the image acquisition module, avoid frequent focusing adjustments of the image acquisition module, and prolong the service life of the image acquisition module, the image acquisition module is focused by the method of “stage focusing”, and the “stage focusing” method is adopted to focus the image acquisition module. "The realization of "relies on the pre-built corresponding relationship between the object distance and the focus segment of the image acquisition module, that is, the corresponding relationship between the object distance interval and the focus position. In an optional implementation manner provided in this embodiment, the following method is adopted Construct the correspondence between the object distance interval and the focus position: use at least one of the image acquisition parameters as a target parameter, and determine the remaining image acquisition parameters as a constraint parameter; for each target parameter, combine the constraint parameters respectively Establish a relationship curve between the object distance and the target parameter of the image acquisition module at each focus position; determine the minimum object distance that the image acquisition module meets the parameter threshold corresponding to the target parameter at each focus position based on the relationship curve And the maximum object distance, and the object distance interval is composed of the minimum object distance and the maximum object distance; by constructing the corresponding relationship between the object distance interval and the focus position of the image acquisition module, the object distance interval and Correspondence between focus positions.

It can be seen that by dividing the object distance of the image acquisition module into a plurality of object distance intervals, and corresponding these 5 object distance intervals with the corresponding focus positions of the image acquisition module, the image acquisition module will then proceed on this basis. During focus adjustment, the object distance interval can be determined according to the actual acquisition distance at the time of acquisition, and then the lens group of the image acquisition module can be adjusted to the focus position corresponding to the determined object distance interval, and the image distance of the image acquisition module can be quickly adjusted to the same The actual acquisition distance is adapted. On the one hand, it avoids repeatedly adjusting the focus position during the focusing process to find a focus position that matches the actual acquisition distance. On the other hand, it also avoids the adjustment range of the image acquisition module during a focus adjustment process. In large cases, the service life of the image acquisition module is prolonged, and equipment maintenance caused by frequent focusing is reduced.

During specific implementation, on the basis of calculating the object distance corresponding to the target object image in the above step S502, determine the object distance interval to which the object distance belongs in the corresponding relationship between the object distance interval and the focus position, and further determine the object distance interval to which the object distance belongs in the corresponding relationship between the object distance interval and the focus position. In the correspondence between the object distance interval and the focus position, the focus position corresponding to the object distance interval to which the object distance belongs is determined.

Step S506: Focus the image acquisition module according to the focus position.

In an optional implementation manner provided by this embodiment, focusing the image acquisition module according to the focus position is specifically implemented in the following manner: issuing a focus instruction to the focus control sub-module configured by the image acquisition module, The focus control sub-module adjusts the lens group configured by the image acquisition module to the focus position according to the focus position carried in the focus instruction, so that the imaging focus of the lens group is exactly at the focus position when the lens group is in the focus position Falling on the photosensitive component.

In summary, the focusing method calculates the object distance between the target object corresponding to the target object image collected by the image acquisition module and the image acquisition module, and determines the object distance to which the object distance belongs according to the correspondence between the object distance interval and the focus position The object distance interval is for the image acquisition module to determine the suitable focus position, and finally adjust the focus of the image acquisition module according to the focus position, which improves the focusing efficiency of the image acquisition module and avoids the frequent operation of the image acquisition module during the focusing process. Focus adjustment, thereby extending the service life of the image acquisition module.

The embodiment of a focusing device provided in this specification is as follows: In the above-mentioned embodiment, a focusing method is provided, and correspondingly, a focusing device is also provided, which will be described below with reference to the accompanying drawings.

Referring to FIG. 6, it shows a schematic diagram of a focusing device provided by this embodiment.

Since the device embodiment corresponds to the method embodiment, the description is relatively simple. For related parts, please refer to the corresponding description of the method embodiment provided above. The device embodiments described below are merely illustrative.

This specification provides a focusing device, including: a processing module 610 and an image acquisition module 620; wherein the processing module 610 is configured to determine the object distance corresponding to the target object image collected by the image acquisition module 620. , And according to the corresponding relationship between the object distance interval and the focus position constructed based on the image acquisition parameters of the image acquisition module 620 in advance, the focus position corresponding to the object distance interval to which the object distance belongs is determined, and downloads to the image acquisition module 620 Send a focus instruction carrying the focus position; the image acquisition module 620 is configured to collect the target object image, and focus according to the focus position carried in the focus instruction issued by the processing module 610 .

Optionally, the corresponding relationship between the object distance interval and the focus position is constructed in the following manner: at least one of the image acquisition parameters is used as a target parameter, and the remaining image acquisition parameters are determined as constraint parameters; Parameters, combining the constraint parameters to establish the relationship curve between the object distance and the target parameter of the image acquisition module 620 at each focus position; based on the relationship curve, it is determined that the image acquisition module 620 satisfies the The minimum object distance and the maximum object distance of the parameter threshold corresponding to the target parameter, and the object distance interval is composed of the minimum object distance and the maximum object distance; by constructing the object distance interval and the focus position of the image acquisition module 620 The corresponding relationship between the object distance interval and the focus position is generated.

Optionally, the determining the object distance corresponding to the target object image collected by the image acquisition module is implemented by calling the depth sensing sub-module 621 configured by the image acquisition module 620, wherein the depth sensing sub-module 621 passes Collecting depth data calculates the actual collection distance between the target object corresponding to the target object image and the image collection module 620, and outputs the calculated actual collection distance as the object distance.

Optionally, the image acquisition module 620 includes: a focus control sub-module 622, a lens group 623, and a photosensitive component 624; wherein, the focus control sub-module 622 is configured to receive a focus instruction issued by the processing module 610, according to The focus position carried in the focus instruction adjusts the lens group 623 configured by the image acquisition module 620 to the focus position.

An embodiment of a computing device provided in this specification is as follows: FIG. 7 is a structural block diagram of a computing device 700 provided according to an embodiment of this specification. The components of the computing device 700 include, but are not limited to, a memory 710 and a processor 720. The processor 720 and the memory 710 are connected through a bus 730, and the database 750 is used to store data.

The computing device 700 also includes an access device 740 that enables the computing device 700 to communicate via one or more networks 760. Examples of these networks include a public switched telephone network (PSTN), a local area network (LAN), a wide area network (WAN), a personal area network (PAN), or a combination of communication networks such as the Internet. The access device 740 may include one or more of any type of wired or wireless network interface (for example, a network interface card (NIC)), such as IEEE802.11 wireless local area network (WLAN) wireless interface, global interconnection for microwave access ( Wi-MAX) interface, Ethernet interface, universal serial bus (USB) interface, cellular network interface, Bluetooth interface, near field communication (NFC) interface, etc.

In an embodiment of this specification, the aforementioned components of the computing device 700 and other components not shown in FIG. 7 may also be connected to each other, for example, via a bus. It should be understood that the structural block diagram of the computing device shown in FIG. 7 is only for the purpose of example, and is not intended to limit the scope of this specification. Those skilled in the art can add or replace other components as needed.

The computing device 700 can be any type of stationary or mobile computing device, including a mobile computer or mobile computing device (for example, a tablet computer, a personal digital assistant, a laptop computer, a notebook computer, a netbook, etc.), a mobile phone (for example, a smart phone). ), wearable computing devices (for example, smart watches, smart glasses, etc.) or other types of mobile devices, or stationary computing devices such as desktop computers or PCs. The computing device 700 may also be a mobile or stationary server.

This specification provides a computing device that includes a memory 710, a processor 720, and computer instructions that are stored in the memory and can run on the processor. The processor 720 is configured to execute the following computer-executable instructions: Calculate the object distance corresponding to the target object image based on the eye feature; The target object image is collected by the image acquisition module; According to the corresponding relationship between the object distance interval and the focus position of the image acquisition module constructed in advance based on the iris image acquisition index, the object distance is determined The focus position corresponding to the object distance interval to which the object distance belongs; the image acquisition module is focused according to the focus position, and an iris image is acquired through the focused image acquisition module.

An example of another computing device provided in this specification is as follows.

FIG. 8 is a structural block diagram of a computing device 800 provided according to an embodiment of the present specification. The components of the computing device 800 include, but are not limited to, a memory 810 and a processor 820. The processor 820 and the memory 810 are connected through a bus 830, and the database 850 is used to store data.

The computing device 800 also includes an access device 840 that enables the computing device 800 to communicate via one or more networks 860. Examples of these networks include a public switched telephone network (PSTN), a local area network (LAN), a wide area network (WAN), a personal area network (PAN), or a combination of communication networks such as the Internet. The access device 840 may include one or more of any type of wired or wireless network interface (for example, a network interface card (NIC)), such as IEEE802.11 wireless local area network (WLAN) wireless interface, global interconnection for microwave access ( Wi-MAX) interface, Ethernet interface, universal serial bus (USB) interface, cellular network interface, Bluetooth interface, near field communication (NFC) interface, etc.

In an embodiment of this specification, the aforementioned components of the computing device 800 and other components not shown in FIG. 8 may also be connected to each other, for example, via a bus. It should be understood that the structural block diagram of the computing device shown in FIG. 8 is only for the purpose of example, and is not intended to limit the scope of this specification. Those skilled in the art can add or replace other components as needed.

The computing device 800 can be any type of stationary or mobile computing device, including mobile computers or mobile computing devices (for example, tablet computers, personal digital assistants, laptop computers, notebook computers, netbooks, etc.), mobile phones (for example, smart phones). ), wearable computing devices (for example, smart watches, smart glasses, etc.) or other types of mobile devices, or stationary computing devices such as desktop computers or PCs. The computing device 800 may also be a mobile or stationary server.

This specification provides a computing device that includes a memory 810, a processor 820, and computer instructions that are stored in the memory and can run on the processor. The processor 820 is used to execute the following computer-executable instructions: determine that the image acquisition module collects The object distance corresponding to the obtained target object image; according to the corresponding relationship between the object distance interval and the focus position constructed based on the image acquisition parameters of the image acquisition module in advance, determine the focus position corresponding to the object distance interval to which the object distance belongs; The focus position focuses on the image acquisition module.

An example of a computer-readable storage medium provided in this specification is as follows: an embodiment of this specification provides a computer-readable storage medium that stores computer instructions that, when executed by a processor, implement the iris image acquisition method step.

The foregoing is a schematic solution of a computer-readable storage medium of this embodiment. It should be noted that the technical solution of the storage medium belongs to the same concept as the technical solution of the above-mentioned iris image acquisition method. For details that are not described in detail in the technical solution of the storage medium, please refer to the description of the technical solution of the above-mentioned iris image acquisition method. .

An example of another computer-readable storage medium provided in this specification is as follows: an embodiment of this specification provides a computer-readable storage medium that stores computer instructions that implement the steps of the focusing method when the instructions are executed by a processor .

The foregoing is a schematic solution of a computer-readable storage medium of this embodiment. It should be noted that the technical solution of the storage medium belongs to the same concept as the technical solution of the above-mentioned focusing method. For details of the technical solution of the storage medium that are not described in detail, please refer to the description of the technical solution of the above-mentioned focusing method.

The foregoing describes specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps described in the claims can be performed in a different order than in the embodiments and still achieve desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or sequential order shown in order to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

The computer instructions include computer program codes, and the computer program codes may be in the form of source code, object code, executable files, or some intermediate forms. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory) , Random Access Memory (RAM, Random Access Memory), electrical carrier signal, telecommunications signal, and software distribution media, etc. It should be noted that the content contained in the computer-readable medium can be appropriately added or deleted according to the requirements of the legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to the legislation and patent practice, the computer-readable medium Does not include electrical carrier signals and telecommunication signals.

It should be noted that for the foregoing method embodiments, for simplicity of description, they are all expressed as a series of action combinations, but those skilled in the art should know that the embodiments of this specification are not subject to the described sequence of actions. Limitation, because according to the embodiments of this specification, some steps can be performed in other order or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the involved actions and modules are not necessarily all required by the embodiments of the specification.

In the above-mentioned embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in an embodiment, reference may be made to related descriptions of other embodiments.

The preferred embodiments of this specification disclosed above are only used to help explain this specification. The optional embodiments do not describe all the details in detail, nor do they limit the invention to only the specific implementations described. Obviously, many modifications and changes can be made according to the content of the embodiments of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the embodiments of this specification, so that those skilled in the art can understand and use this specification well. This description is only limited by the claims and their full scope and equivalents.

Claims (19)

1. An iris image acquisition method, including:

   Calculating the object distance corresponding to the target object image based on the eye features in the target object image; the target object image is collected by the image acquisition module;

   Determining the focus position corresponding to the object distance interval to which the object distance belongs according to the correspondence between the object distance interval and the focus position of the image acquisition module constructed in advance based on the iris image acquisition index;

   The image acquisition module is focused according to the focus position, and an iris image is acquired through the focused image acquisition module.
2. The iris image acquisition method according to claim 1, wherein the corresponding relationship between the object distance interval and the focus position is constructed in the following manner:

   According to the image parameter corresponding to the iris image acquisition index, at least one image parameter is used as a target parameter, the target constraint condition corresponding to the target parameter is determined according to the iris image acquisition index, and the remaining ones are determined according to the iris image acquisition index. The fixed constraint conditions corresponding to the image parameters;

   For each target parameter, the relationship curve between the object distance and the target parameter at each focus position of the image acquisition module is established under the constraints of the fixed constraint conditions;

   Determine, based on the relationship curve, a minimum object distance and a maximum object distance that the image acquisition module meets the target constraint condition at each focus position, and an object distance interval is composed of the minimum object distance and the maximum object distance;

   By constructing the correspondence between the object distance interval and the focus position of the image acquisition module, the correspondence relationship between the object distance interval and the focus position is generated.
3. The iris image acquisition method according to claim 1, wherein the calculation of the object distance corresponding to the target object image based on the eye features is implemented by calling a depth sensing sub-module configured by the image acquisition module, wherein The depth sensing sub-module calculates the actual collection distance between the eye of the target object corresponding to the target object image and the image collection module by collecting depth data, and outputs the calculated actual collection distance as the object distance .
4. The iris image acquisition method according to claim 1, wherein the step of calculating the object distance corresponding to the target object image based on the eye characteristics in the case that eye features are detected in the target object image collected by the image acquisition module After execution, and according to the corresponding relationship between the object distance interval and the focus position of the image acquisition module constructed based on the iris image acquisition index in advance, the step of determining the focus position corresponding to the object distance interval to which the object distance belongs before execution includes:

   Searching whether there is an object distance interval to which the object distance belongs in the correspondence between the object distance interval and the focus position;

   If it exists, execute the step of determining the focus position corresponding to the object distance interval to which the object distance belongs according to the corresponding relationship between the object distance interval and the focus position of the image acquisition module constructed in advance based on the iris image acquisition index;

   If it does not exist, an image of the target object is collected through the image acquisition module and eye feature detection is performed.
5. The iris image acquisition method according to claim 1, wherein the focusing the image acquisition module according to the focusing position comprises:

   A focus instruction is issued to the focus control sub-module configured by the image acquisition module, and the focus control sub-module adjusts the lens group configured by the image acquisition module to the focus position according to the focus position carried in the focus instruction. Focus position.
6. An iris image acquisition device, including:

   Processing module, image acquisition module;

   Wherein, the processing module is configured to calculate the object distance corresponding to the target object image based on the eye features in the target object image, and according to the object distance interval and the focus position of the image acquisition module constructed in advance based on the iris image acquisition index Correspondence, determining the focus position corresponding to the object distance interval to which the object distance belongs, and issuing a focus instruction carrying the focus position to the image acquisition module; the target object image is acquired by the image acquisition module;

   The image acquisition module is configured to acquire the target object image, perform focusing according to the focusing position carried in the focusing instruction issued by the processing module, and acquire an iris image after focusing.
7. The iris image acquisition device according to claim 6, wherein the corresponding relationship between the object distance interval and the focus position is constructed in the following manner:

   According to the image parameter corresponding to the iris image acquisition index, at least one image parameter is used as a target parameter, the target constraint condition corresponding to the target parameter is determined according to the iris image acquisition index, and the remaining ones are determined according to the iris image acquisition index. The fixed constraint conditions corresponding to the image parameters;

   For each target parameter, the relationship curve between the object distance and the target parameter at each focus position of the image acquisition module is established under the constraints of the fixed constraint conditions;

   Determine, based on the relationship curve, a minimum object distance and a maximum object distance that the image acquisition module meets the target constraint condition at each focus position, and an object distance interval is composed of the minimum object distance and the maximum object distance;

   By constructing the correspondence between the object distance interval and the focus position of the image acquisition module, the correspondence relationship between the object distance interval and the focus position is generated.
8. The iris image acquisition device according to claim 6, wherein the image acquisition module is configured with a depth sensing sub-module, wherein the depth sensing sub-module calculates the eye of the target object corresponding to the target object image by collecting depth data The actual acquisition distance between the image acquisition module and the image acquisition module, and the calculated actual acquisition distance is output as the object distance.
9. The iris image acquisition device according to claim 6, wherein the image acquisition module comprises: a focus control sub-module, a lens group and a photosensitive component;

   Wherein, the focus control sub-module is configured to receive the focus instruction carrying the focus position issued by the processing module, and adjust the lens group to the focus position according to the focus instruction.
10. A focusing method includes:

    Determine the object distance corresponding to the target object image collected by the image collection module;

    Determine the focus position corresponding to the object distance interval to which the object distance belongs according to the corresponding relationship between the object distance interval and the focus position constructed based on the image acquisition parameters of the image acquisition module in advance;

    Focusing the image acquisition module according to the focus position.
11. According to the focusing method of claim 10, the corresponding relationship between the object distance interval and the focusing position is constructed in the following manner:

    Taking at least one of the image acquisition parameters as a target parameter, and determining the remaining image acquisition parameters as constraint parameters;

    For each target parameter, the relationship curve between the object distance and the target parameter of the image acquisition module at each focus position is established in combination with the constraint parameter;

    The minimum object distance and the maximum object distance that the image acquisition module meets the parameter threshold corresponding to the target parameter at each focus position are determined based on the relationship curve, and are composed of the minimum object distance and the maximum object distance Distance interval

    By constructing the correspondence between the object distance interval and the focus position of the image acquisition module, the correspondence relationship between the object distance interval and the focus position is generated.
12. The focusing method according to claim 10, wherein the step of determining the object distance corresponding to the target object image collected by the image acquisition module is implemented by calling a depth sensing sub-module configured by the image acquisition module, wherein the depth transmission The sensor module calculates the actual collection distance between the target object corresponding to the target object image and the image collection module by collecting depth data, and outputs the calculated actual collection distance as the object distance.
13. The focusing method according to claim 10, after the step of determining the object distance corresponding to the target object image collected by the image acquisition module is executed, and the object distance interval constructed based on the image acquisition parameters of the image acquisition module in advance The corresponding relationship with the focus position, before the step of determining the focus position corresponding to the object distance interval to which the object distance belongs, includes:

    Searching whether there is an object distance interval to which the object distance belongs in the correspondence between the object distance interval and the focus position;

    If it exists, execute the step of determining the focus position corresponding to the object distance interval to which the object distance belongs according to the corresponding relationship between the object distance interval and the focus position constructed based on the image acquisition parameters of the image acquisition module in advance;

    If it does not exist, an image of the target object is acquired through the image acquisition module, and the step of determining the object distance corresponding to the image of the target object acquired by the image acquisition module is returned to execute.
14. The focusing method according to claim 10, wherein the focusing the image acquisition module according to the focusing position comprises:

    A focus instruction is issued to the focus control sub-module configured by the image acquisition module, and the focus control sub-module adjusts the lens group configured by the image acquisition module to the focus position according to the focus position carried in the focus instruction. Focus position.
15. A focusing device includes:

    Processing module, image acquisition module;

    Wherein, the processing module is configured to determine the object distance corresponding to the image of the target object collected by the image acquisition module, and to determine the object distance interval and focus based on the image acquisition parameters of the image acquisition module in advance. Position correspondence, determining the focus position corresponding to the object distance interval to which the object distance belongs, and issue a focus instruction carrying the focus position to the image acquisition module;

    The image acquisition module is configured to acquire the target object image, and perform focusing according to the focusing position carried in the focusing instruction issued by the processing module.
16. A computing device including:

    Memory and processor;

    The memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions:

    Calculating the object distance corresponding to the target object image based on the eye features in the target object image; the target object image is collected by the image acquisition module;

    Determine the focus position corresponding to the object distance interval to which the object distance belongs according to the correspondence between the object distance interval and the focus position of the image acquisition module constructed in advance based on the iris image acquisition index;

    The image acquisition module is focused according to the focus position, and an iris image is acquired through the focused image acquisition module.
17. A computing device including:

    Memory and processor;

    The memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions:

    Determine the object distance corresponding to the target object image collected by the image collection module;

    Determine the focus position corresponding to the object distance interval to which the object distance belongs according to the corresponding relationship between the object distance interval and the focus position constructed based on the image acquisition parameters of the image acquisition module in advance;

    Focusing the image acquisition module according to the focus position.
18. A computer-readable storage medium, which stores computer instructions that, when executed by a processor, implement the steps of the iris image acquisition method described in any one of claims 1 to 5.
19. A computer-readable storage medium, which stores computer instructions, which, when executed by a processor, implement the steps of the focusing method described in any one of claims 10 to 14.

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