CN106888352B

CN106888352B - Coke pushing position determining method and device

Info

Publication number: CN106888352B
Application number: CN201510947084.4A
Authority: CN
Inventors: 胡文迪
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2015-12-16
Filing date: 2015-12-16
Publication date: 2020-12-18
Anticipated expiration: 2035-12-16
Also published as: CN106888352A; WO2016188186A1

Abstract

The invention discloses a method and a device for determining a pushing position, wherein the method for determining the pushing position comprises the following steps: acquiring a set of foreground distance information within a given focusing time; fitting according to the foreground distance information to obtain a maximum probability foreground position; and taking the maximum probability foreground position as a coke pushing position. The invention effectively solves the technical problem of fuzzy shooting effect caused by the ceaseless movement of the motor during focusing in the prior art, and achieves the technical effect of avoiding fuzzy shooting effect.

Description

Coke pushing position determining method and device

Technical Field

The invention relates to the field of camera shooting, in particular to a method and a device for determining a coke pushing position.

Background

In the process of debugging focusing parameters in a project, if a scene is shot externally, it is found that a shot object moves ceaselessly due to the influence of wind, so that the shot scene is fuzzy, and great inconvenience is brought to a user.

At present, in a terminal photographing system, if focusing is performed by using a depth-of-field focusing method, a depth-of-field position of a current region of interest (ROI) is generally calculated first, then the current position is obtained by stepping to the current position, and finally a preset algorithm is used to perform appropriate adjustment.

However, the above-mentioned method cannot solve the problem of blurring of the scene, and the scene position changes already during the moving process of the motor due to the scene moving too fast, which shows that the motor stretches continuously at different positions in the user experience.

Disclosure of Invention

The invention provides a method and a device for determining a focus pushing position, which are used for solving the technical problem of fuzzy shooting effect caused by continuous movement of a motor during focusing in the prior art.

In order to solve the above technical problem, in one aspect, the present invention provides a method for determining a coke pushing position, including: acquiring a set of foreground distance information within a given focusing time; fitting according to the foreground distance information to obtain a maximum probability foreground position; and taking the maximum probability foreground position as a coke pushing position.

Further, acquiring a set of foreground distance information within a given focusing time includes: calculating the foreground distance once every preset time interval within the given focusing time; and forming a group of foreground distance information in the given focusing time by the calculated foreground distance data.

Further, calculating a foreground distance, comprising: determining a foreground area according to the distribution condition of the depth points; and calculating a foreground distance according to the positions of the plurality of depth of field points in the foreground area.

Further, calculating a foreground distance according to the positions of the plurality of depth-of-field points of the foreground region, including: calculating an average value of the depth distances of a plurality of depth points of the foreground area; and taking the obtained average value as the foreground distance obtained by the calculation.

Further, fitting according to the foreground distance information to obtain a maximum probability foreground position, including: and fitting by a Monte Carlo method to obtain the maximum probability foreground position.

In another aspect, the present invention provides a coke pushing position determining apparatus, including: the acquisition module is used for acquiring a group of foreground distance information within a given focusing time; the fitting module is used for fitting according to the foreground distance information to obtain a maximum probability foreground position; and the coke pushing position determining module is used for taking the maximum probability foreground position as a coke pushing position.

Further, the obtaining module includes: the computing unit is used for computing the foreground distance once every preset time interval in the given focusing time; and the acquisition unit is used for forming the calculated foreground distance data into a group of foreground distance information within the given focusing time.

Further, the calculation unit includes: the determining subunit is used for determining a foreground area according to the distribution condition of the depth points; and the calculating subunit is used for calculating a foreground distance according to the positions of the depth points in the foreground area.

Further, the calculating subunit is specifically configured to calculate an average value of depth-of-field distances of a plurality of depth-of-field points in the foreground area, and use the calculated average value as the foreground distance obtained by the current calculation.

Further, the fitting module is specifically configured to obtain the maximum probability foreground position by fitting through a monte carlo method.

The method determines the most probable foreground position by utilizing a group of foreground distance information in focusing time, namely determines the foreground position with the maximum probability, and then takes the position as the focus pushing position. By means of the mode, the technical problem that in the prior art, due to the fact that the motor does not stop moving during focusing, the shooting effect is fuzzy is solved, and the technical effect of avoiding the shooting effect from being fuzzy is achieved.

Drawings

FIG. 1 is a flow chart of a method of determining a position of a pushing ram in an embodiment of the present invention;

FIG. 2 is a pictorial illustration of depth of field in an embodiment of the present invention;

fig. 3 is a block diagram showing the structure of the coke pushing position determining apparatus in the embodiment of the present invention;

fig. 4 is another block diagram of the structure of the coke pushing position determining apparatus in the embodiment of the present invention;

fig. 5 is still another configuration block diagram of the coke pushing position determining apparatus in the embodiment of the invention;

FIG. 6 is a diagram illustrating the distribution of the quasi-focal positions in the embodiment of the present invention.

Detailed Description

In order to solve the technical problem of the prior art that the shooting effect is blurred due to the fact that a motor does not stop moving during focusing, the invention provides a method for determining a focus pushing position, and the method is further described in detail below with reference to the accompanying drawings and two embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the invention.

For a more clear understanding of the present invention, the following terms are to be interpreted:

1) focusing and focusing points:

when shooting, the process of adjusting the lens of the camera to clearly image a scene at a certain distance from the camera is called focusing, and the point where the scene is located is called a focusing point.

2) Depth of field:

since "sharpness" is not an absolute concept, the image of the subject in a certain distance both before the focus (direction close to the camera) and after the focus (direction away from the camera) can be sharp, and the sum of the front and rear ranges is called the depth of field, that is, the subject in the front and rear ranges can be clearly photographed.

The depth of field is mainly related to the distance between the aperture, the lens and the object to be photographed, and generally, the larger the aperture (the smaller the aperture value f), the shallower the depth of field, and the smaller the aperture (the larger the aperture value f), the deeper the depth of field; the depth of field is shallower as the focal length of the lens is longer, and the depth of field is deeper as the focal length of the lens is shorter; the closer the subject is, the shallower the depth of field is, and the farther the subject is, the deeper the depth of field is. Secondly, the foreground depth is less than the back depth of field, i.e. after accurate focusing, only scenes in a short distance in front of the focus can be imaged clearly, while scenes in a long distance behind the focus are imaged clearly.

3) Foreground distance:

the foreground is relative to the background, and in the embodiment of the present invention, the foreground refers to a moving object in front of the picture in which the user is interested, and the foreground distance is the distance between the shot and the picture in which the user is interested. Generally, a foreground moving object is interested by a user, the distance between the object interested by the user and a lens is required to be determined for photographing, and the background distance is used for confirming whether a scene concerned is entered. Wherein the background distance is fixed and the foreground distance is vibrated within a certain range.

The embodiment of the invention provides a method for determining a coke pushing position, the flow of the method is shown in fig. 1, and the method comprises steps S102 to S106:

s102, acquiring a group of foreground distance information in given focusing time;

s104: fitting according to the foreground distance information to obtain a maximum probability foreground position;

s106: and taking the maximum probability foreground position as a coke pushing position.

And equivalently, carrying out probability statistics according to a group of foreground distance information to determine the position point at which the foreground distance has the highest probability, and taking the position point with the highest probability as the coke pushing position.

In step S102, the foreground distance information may be acquired by a binocular camera or an infrared laser focusing device. Since it is considered that the focusing has a certain focusing time, a set of foreground distance information in the focusing time may be obtained, and the set of foreground distance information may be obtained by calculating the foreground distance at predetermined time intervals in a given focusing time and then combining the calculated foreground distance data into a set of foreground distance information in the given focusing time.

Further, the longer a given focusing time is, the more accurate the relative subsequently determined position will be, and the shorter the predetermined time interval is within the same focusing time, the more accurate the relative subsequently determined position will be. Of course, the shorter the interval, the higher the data processing capacity of the device, and therefore the size of the time interval specifically adopted can be selected according to actual situations and needs.

In order to make the determined foreground distance more reasonable, a foreground region may be determined according to the distribution of the depth points, as shown in fig. 2, the foreground region is a foreground region, and the background region is a background region, and then a foreground distance is calculated according to the positions of the depth points in the foreground region.

Specifically, an average value of depth-of-field distances of a plurality of depth-of-field points in the foreground region may be obtained, and then the obtained average value is used as the current foreground distance obtained through calculation, for example, the foreground distance d may be calculated according to the following formula:

wherein d represents the calculated foreground distance, d_iAnd the foreground distance of the ith depth point of the foreground area is represented, and n represents the number of the depth points of the foreground area.

The average depth of a plurality of depth points is used as the determined foreground distance in the above example, which is mainly based on the consideration of big data, i.e. the more data, the more accurate the result obtained by averaging.

In step 104, the maximum probability foreground position may be obtained by fitting through a monte carlo method. The processing idea of the monte carlo method is to estimate the probability of a certain random event according to the frequency of the event occurrence or obtain some digital features of the random variable as the solution of the problem by some "experiment" method when the problem to be solved is the probability of the occurrence of the random event or the expected value of the random variable.

However, it should be noted that the maximum probability foreground position obtained by fitting through the monte carlo method is not the only probability fitting method, and other probability statistics methods may also be used to determine the maximum probability foreground position, which is specifically selected, and the present application is not limited thereto.

In this embodiment, a coke pushing position determining apparatus is further provided, and the apparatus is used to implement the foregoing embodiments and preferred embodiments, which have already been described and are not described again. As used below, the term "unit" or "module" may implement a combination of software and/or hardware of predetermined functions. Although the means described in the embodiments below are preferably implemented in software, an implementation in hardware, or a combination of software and hardware is also possible and contemplated. Fig. 3 is a block diagram of a preferred structure of a coke pushing position determining apparatus according to an embodiment of the present invention, and as shown in fig. 3, the apparatus may include:

an obtaining module 301, configured to obtain a set of foreground distance information within a given focusing time;

a fitting module 302, configured to fit according to the foreground distance information to obtain a maximum probability foreground position;

and a coke pushing position determining module 303, configured to use the foreground position with the maximum probability as a coke pushing position.

In one embodiment, as shown in fig. 4, the obtaining module 301 may include: a calculating unit 3011, configured to calculate a foreground distance at predetermined time intervals within the given focusing time; and the obtaining unit 3012 is configured to combine the calculated foreground distance data into a set of foreground distance information within the given focusing time.

In one embodiment, the computing unit 3011 may include: the determining subunit is used for determining a foreground area according to the distribution condition of the depth points; and the calculating subunit is used for calculating a foreground distance according to the positions of the depth points in the foreground area.

In an embodiment, the calculating subunit may be specifically configured to find an average value of depth distances of a plurality of depth points in the foreground region, and use the found average value as the foreground distance obtained by the current calculation.

In an embodiment, the fitting module 302 may be specifically configured to obtain the maximum probability foreground position by fitting through a monte carlo method.

PREFERRED EMBODIMENTS

In order to better illustrate the present invention, a specific embodiment is provided in this example for illustration, however, this is only a specific example and should not be construed as a limitation to the present invention.

The whole photographing apparatus may include: the terminal photographing module provides a normal photographing function, the image depth-of-field calculation module can be a current mainstream binocular distance measurement module or a laser distance measurement module, and the most probable focusing control module is used for fitting a most probable quasi-focusing position according to depth information of a scene depth table of a region needing to be focused, which is input within a period of time, and pushing the motor to the position.

As shown in fig. 5, a specific structural diagram of the coke pushing position determining apparatus is shown, which includes: a foreground distance calculating module 501 (equivalent to the acquiring module 301), a maximum focusing probability position calculating module 502 (equivalent to the fitting module 302), and a push motor module 503 (equivalent to the push position determining module 303).

The foreground distance calculation module 501 and the maximum position of quasi-focus probability calculation module 502 may calculate the maximum position of quasi-focus probability according to the following steps:

s1: calculating the single foreground distance:

the foreground distance calculating module 501 calculates the depth map, and then distinguishes the foreground region according to the difference in the distribution of the foreground point and the background point.

Then, the depth distances of the depth points in the foreground region are averaged according to the following formula:

S2: within a given focusing time T, a single foreground distance calculation is performed every σ T and recorded, and a quasi-focus position distribution diagram shown in fig. 6 is obtained, in fig. 6, the ordinate represents the distance (i.e., the depth-of-field distance), and the abscissa represents the normalization time.

In the actual implementation process, this focusing time T may be a given time constant value, considering that the longer the given time is, the more points are obtained, the higher the fitting precision is theoretically, because the time for obtaining the points per unit distance is determined, but the more points are obtained, the higher the processing and calculation costs and the calculation time are, and therefore, a trade-off needs to be made between the precision and the calculation cost.

S3: and fitting the foreground position with the maximum probability at the most densely distributed position as the coke pushing position for output.

In particular, in the implementation, the following principles may be followed:

1) the focusing time is controllable, and within a given focusing time, the in-focus position of the region of interest within the time period is recorded. In a scene with less drastic change of the scene distance, the longer the recording time, the more accurate the focusing is.

2) A point that is approximately constant in the depth information of the scene is required as a reference point for identifying the scene.

3) And identifying foreground and background areas according to the distribution of the depth points, fitting a foreground distance in the foreground depth points, repeating the operation at the same time interval, recording the foreground distances of a plurality of periods at continuous intervals, and fitting the maximum probability foreground position by utilizing the Monte Carlo method principle.

4) When the motor is fixed at the most probable position, the probability of focus being clear at this position is the greatest, thereby making the focus distance obtained more accurate.

In summary, the present invention determines the most probable foreground position by using a set of foreground distance information within the focusing time, i.e. determines the foreground position with the maximum probability, and then uses the position as the focus-pushing position. By means of the mode, the technical problem that in the prior art, due to the fact that the motor does not stop moving during focusing, the shooting effect is fuzzy is solved, and the technical effect of avoiding the shooting effect from being fuzzy is achieved.

It will be apparent to those skilled in the art that the modules or steps of the present invention described above may be implemented by a general purpose computing device, they may be centralized on a single computing device or distributed across a network of multiple computing devices, and alternatively, they may be implemented by program code executable by a computing device, such that they may be stored in a storage device and executed by a computing device, and in some cases, the steps shown or described may be performed in an order different than that described herein, or they may be separately fabricated into individual integrated circuit modules, or multiple ones of them may be fabricated into a single integrated circuit module. Thus, the present invention is not limited to any specific combination of hardware and software.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, and the scope of the invention should not be limited to the embodiments described above.

Claims

1. A method for determining a coke pushing position, comprising:

acquiring a set of foreground distance information within a given focusing time;

fitting according to the foreground distance information to obtain a maximum probability foreground position, comprising: fitting by a Monte Carlo method to obtain the maximum probability foreground position;

and taking the maximum probability foreground position as a coke pushing position.

2. The method of claim 1, wherein obtaining a set of foreground distance information for a given focus time comprises:

calculating the foreground distance once every preset time interval within the given focusing time;

and forming a group of foreground distance information in the given focusing time by the calculated foreground distance data.

3. The method of claim 2, wherein computing a foreground distance comprises:

determining a foreground area according to the distribution condition of the depth points;

and calculating a foreground distance according to the positions of the plurality of depth of field points in the foreground area.

4. The method of claim 3, wherein calculating a foreground distance based on the positions of the plurality of depth points of the foreground region comprises:

calculating an average value of the depth distances of a plurality of depth points of the foreground area;

and taking the obtained average value as the foreground distance obtained by the calculation.

5. A coke pushing position determining apparatus, comprising:

the acquisition module is used for acquiring a group of foreground distance information within a given focusing time;

the fitting module is used for fitting according to the foreground distance information to obtain a maximum probability foreground position, and is specifically used for fitting through a Monte Carlo method to obtain the maximum probability foreground position;

and the coke pushing position determining module is used for taking the maximum probability foreground position as a coke pushing position.

6. The apparatus of claim 5, wherein the acquisition module comprises:

the computing unit is used for computing the foreground distance once every preset time interval in the given focusing time;

and the acquisition unit is used for forming the calculated foreground distance data into a group of foreground distance information within the given focusing time.

7. The apparatus of claim 6, wherein the computing unit comprises:

the determining subunit is used for determining a foreground area according to the distribution condition of the depth points;

and the calculating subunit is used for calculating a foreground distance according to the positions of the depth points in the foreground area.

8. The apparatus according to claim 7, wherein the computing subunit is specifically configured to calculate an average value of depth distances of a plurality of depth points in the foreground region, and use the calculated average value as the foreground distance obtained by the current calculation.