CN107918278B - Automatic focus following method for film and television lens - Google Patents
Automatic focus following method for film and television lens Download PDFInfo
- Publication number
- CN107918278B CN107918278B CN201711137633.7A CN201711137633A CN107918278B CN 107918278 B CN107918278 B CN 107918278B CN 201711137633 A CN201711137633 A CN 201711137633A CN 107918278 B CN107918278 B CN 107918278B
- Authority
- CN
- China
- Prior art keywords
- focus
- data
- follower
- following
- equation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B13/00—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion
- G05B13/02—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric
- G05B13/04—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric involving the use of models or simulators
- G05B13/042—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric involving the use of models or simulators in which a parameter or coefficient is automatically adjusted to optimise the performance
Landscapes
- Engineering & Computer Science (AREA)
- Software Systems (AREA)
- Artificial Intelligence (AREA)
- Computer Vision & Pattern Recognition (AREA)
- Evolutionary Computation (AREA)
- Medical Informatics (AREA)
- Health & Medical Sciences (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Automation & Control Theory (AREA)
- Studio Devices (AREA)
- Lens Barrels (AREA)
- Automatic Focus Adjustment (AREA)
Abstract
The invention discloses an automatic focus following method for a film and television lens, which comprises the following steps: s1: the PC software end sends and receives the data of the focus follower, and controls the servo motor to control the lens focus ring through a data signal; s2: establishing a functional relation between the focus follower data and the actual physical data; s3: an automatic focus following scheme is generated. The invention realizes the communication between the PC software end and the focus follower, constructs the functional relation between the focus follower data and the actual physical data, and realizes the automatic focus follower scheme. The method can be applied to the film and television shooting field, and provides a set of software-controlled focus following implementation scheme for focus following personnel.
Description
Technical Field
The invention relates to the field of computer software, in particular to an automatic focus following method for a film and television lens.
Background
The focus tracking in movie shooting refers to changing the focal length as a person or object approaches or moves away from the camera while shooting a lens so that it remains in precise focus.
In actual shooting, a person in focus needs to try each focus position, mark a lens, and operate the focus follower to focus while paying attention to the walking position of an actor and the progress of a plot when shooting.
With the development of the technology, a wireless focus following system appears, the focus is not required to be marked on a lens, a focus following person can still control the focus through a wireless controller even if the person is far away from a camera for 300 meters through a wireless radio frequency technology, and the action of the person is completely liberated by benefiting from a wireless remote control function, so that the person can be concentrated in focus control only by keeping a proper distance with the photographer without considering the position of the photographer and the position of a connecting line.
With the development of shooting technology, the need for a focus following system controlled by software is increasing. The method adopts COM serial port communication, sends command data to a focus follower, controls a focus ring to realize real-time focus following, provides a software-controlled focusing method for shooting personnel on a movie shooting site, and can store lens data and provide materials for post-production.
At present, an existing wireless tracking system, such as Cmotion, TILTA, etc., has a function of controlling a focus ring through software, but the control of the focus ring does not implement a one-to-one mapping relation with an actual distance, that is, a user of physical data of a focus distance does not know, and meanwhile, although the software provides a control function, the movement transition between the positions of the focus ring still needs to be controlled by a worker, and automatic focus following is not implemented.
Disclosure of Invention
The purpose of the invention is as follows: in order to overcome the defects in the prior art, the invention provides an automatic focus following method for a film and television lens, which can solve the defects in the prior art.
The technical scheme is as follows: the invention relates to an automatic focus following method for a film and television lens, which comprises the following steps:
s1: the PC software end sends and receives the data of the focus follower, and controls the servo motor to control the lens focus ring through a data signal;
s2: establishing a functional relation between the focus follower data and the actual physical data;
s3: an automatic focus following scheme is generated.
Further, the step S2 specifically includes the following steps:
s2.1: controlling the lens focal ring to rotate to the corresponding scale Y { Y1,y2...,ynN data in total, and recording the focus follower data X { X corresponding to each scale1,x2,...,xn};
S2.2: and fitting a function curve between the focus tracker data and the actual physical focusing data, and calculating curve parameters.
Further, the step S2.2 specifically includes the following steps:
s2.21: taking scale Y { Y1,y2...,ynThe reciprocal of, i.e. the actual physical focus data, is recorded as
s2.24: establishing a mathematical model aX + b + Y 'of Y' and X as 0, and calculating parameters according to the formula (1)
Further, the step S3 specifically includes the following steps:
s3.1: establishing the focus f by equation (2)1To the focal point f2Focal position equation for the change transition:
f(t)=a0+a1t+a2t2+a3t3 (2)
in the formula (2), a0、a1、a2、a3For the parameter to be calculated, t is the focus f1To the focal point f2The time of the change process;
establishing the focus f by equation (3)1To the focal point f2Varying the speed of the transitionDegree equation, establishing the focus f by equation (4)1To the focal point f2Acceleration equation for change transitions:
s3.2: solving a according to the constraint relation shown in the formula (5)0、a1、a2、a3To obtain a specific form of the focal position equation f (t):
in the formula (5), T is a focal point f1Transition to focus f2The actual required run time;
s3.3: obtaining a one-to-one mapping relation between the focal position and the focus follower data according to the focal position equation f (t) obtained in the step S3.2 and the functional relation between the focus follower data and the actual physical data obtained in the step S2;
s3.4: and sending the focus follower data corresponding to the focus position to a focus follower to realize automatic focus follower.
Further, in step S1, the PC software sends and receives focus follower data via the serial port.
Has the advantages that: compared with the prior art, the invention has the following beneficial effects:
1) the automatic transition process from one focus to another focus is realized, and compared with the traditional manual control, the efficiency and the accuracy of a software-controlled focal ring are improved;
2) the mathematical model is used for fitting the focus follower data and the actual physical focusing data, so that the accuracy of controlling physical focusing is improved.
Drawings
FIG. 1 is a diagram illustrating step S1 according to an embodiment of the present invention;
fig. 2 is a schematic diagram of step S3 according to the embodiment of the present invention.
Detailed Description
The technical solution of the present invention will be further described with reference to the following detailed description and accompanying drawings.
The specific embodiment discloses an automatic focus following method for a film and television lens, which comprises the following steps:
s1: the PC software end sends and receives the data of the focus follower through the serial port, and controls the servo motor to control the lens focus ring through a data signal, as shown in figure 1.
S2: establishing a functional relation between the focus tracker data and the actual physical data, specifically comprising the following steps:
s2.1: controlling the lens focal ring to rotate to the corresponding scale Y { Y1,y2...,ynN data in total, and recording the focus follower data X { X corresponding to each scale1,x2,...,xn};
S2.2: fitting a function curve between the focus follower data and the actual physical focusing data, and calculating curve parameters, wherein the method specifically comprises the following steps of:
s2.21: taking scale Y { Y1,y2...,ynThe reciprocal of, i.e. the actual physical focus data, is recorded as
s2.24: establishing a mathematical model aX + b + Y 'of Y' and X as 0, and calculating parameters according to the formula (1)
S3: generating an automatic focus following scheme, as shown in fig. 2, specifically includes the following steps:
s3.1: establishing the focus f by equation (2)1To the focal point f2Focal position equation for the change transition:
f(t)=a0+a1t+a2t2+a3t3(2)
in the formula (2), a0、a1、a2、a3For the parameter to be calculated, t is the focus f1Time to focus change process;
establishing the focus f by equation (3)1To the focal point f2Changing the velocity equation of the transition process, establishing the focus f by equation (4)1To the focal point f2Acceleration equation for change transitions:
s3.2: solving a according to the constraint relation shown in the formula (5)0、a1、a2、a3To obtain a specific form of the focal position equation f (t):
in the formula (5), T is a focal point f1TransitionTo the focal point f2The actual required run time;
s3.3: obtaining a one-to-one mapping relation between the focal position and the focus follower data according to the focal position equation f (t) obtained in the step S3.2 and the functional relation between the focus follower data and the actual physical data obtained in the step S2;
s3.4: and sending the focus follower data corresponding to the focus position to a focus follower to realize automatic focus follower.
Therefore, the specific embodiment realizes the communication between the software and the focus follower, constructs the functional relation between the data of the focus follower and the actual physical data, realizes a set of focus transition scheme, and finally realizes the application of automatic focus following. The method can be applied to the film and television shooting field, and provides a set of software-controlled focus following implementation scheme for focus following personnel.
Claims (4)
1. A method for automatically following focus of a film and television lens is characterized by comprising the following steps: the method comprises the following steps:
s1: the PC software end sends and receives the data of the focus follower, and controls the servo motor to control the lens focus ring through a data signal;
s2: establishing a functional relation between the focus follower data and the actual physical data;
s3: generating an automatic focus following scheme;
the step S3 specifically includes the following steps:
s3.1: establishing the focus f by equation (2)1To the focal point f2Focal position equation for the change transition:
f(t)=a0+a1t+a2t2+a3t3 (2)
in the formula (2), a0、a1、a2、a3For the parameter to be calculated, t is the focus f1To the focal point f2The time of the change process;
establishing the focus f by equation (3)1To the focal point f2Changing the velocity equation of the transition process, establishing the focus f by equation (4)1To the focal point f2Acceleration equation for change transitions:
s3.2: solving a according to the constraint relation shown in the formula (5)0、a1、a2、a3To obtain a specific form of the focal position equation f (t):
in the formula (5), T is a focal point f1Transition to focus f2The actual required run time;
s3.3: obtaining a one-to-one mapping relation between the focal position and the focus follower data according to the focal position equation f (t) obtained in the step S3.2 and the functional relation between the focus follower data and the actual physical data obtained in the step S2;
s3.4: and sending the focus follower data corresponding to the focus position to a focus follower to realize automatic focus follower.
2. The method for automatically tracking a film and television lens according to claim 1, wherein: the step S2 specifically includes the following steps:
s2.1: controlling the lens focal ring to rotate to the corresponding scale Y { Y1,y2...,ynN data in total, and recording the focus follower data X { X corresponding to each scale1,x2,...,xn};
S2.2: and fitting a function curve between the focus tracker data and the actual physical focusing data, and calculating curve parameters.
3. The method for automatically tracking a film and television lens according to claim 2, wherein: the step S2.2 specifically includes the steps of:
s2.21: taking scale Y { Y1,y2...,ynThe reciprocal of, i.e. the actual physical focus data, is recorded as
s2.24: establishing a mathematical model aX + b + Y 'of Y' and X as 0, and calculating parameters according to the formula (1)
4. The method for automatically tracking a film and television lens according to claim 1, wherein: in step S1, the PC software sends and receives focus follower data via the serial port.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201711137633.7A CN107918278B (en) | 2017-11-16 | 2017-11-16 | Automatic focus following method for film and television lens |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201711137633.7A CN107918278B (en) | 2017-11-16 | 2017-11-16 | Automatic focus following method for film and television lens |
Publications (2)
Publication Number | Publication Date |
---|---|
CN107918278A CN107918278A (en) | 2018-04-17 |
CN107918278B true CN107918278B (en) | 2021-01-19 |
Family
ID=61895622
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201711137633.7A Active CN107918278B (en) | 2017-11-16 | 2017-11-16 | Automatic focus following method for film and television lens |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN107918278B (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2022061519A1 (en) * | 2020-09-22 | 2022-03-31 | 深圳市大疆创新科技有限公司 | Photographing control method and apparatus, gimbal, and follow focus motor |
Family Cites Families (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS58123277A (en) * | 1982-01-19 | 1983-07-22 | Asahi Optical Co Ltd | Automatic focusing device of video camera |
KR100358859B1 (en) * | 2000-05-19 | 2002-10-31 | 주식회사 씨앤비텍 | Method for automatic focus control in a camera |
JP2008015273A (en) * | 2006-07-06 | 2008-01-24 | Olympus Imaging Corp | Camera system and digital camera |
JP2009258680A (en) * | 2008-03-27 | 2009-11-05 | Panasonic Corp | Camera system, camera body, interchangeable lens unit, focus control method, and program |
CN102801914A (en) * | 2012-08-21 | 2012-11-28 | 深圳市影歌科技有限公司 | Digital camera electronic focus tracking device and zoom method |
CN104408704A (en) * | 2014-08-25 | 2015-03-11 | 太仓中科信息技术研究院 | Automatic zoom lens calibration device and calibration method |
KR101932546B1 (en) * | 2014-09-30 | 2018-12-27 | 한화테크윈 주식회사 | Apparatus and method for finding optimal zooming speed in auto-focus camera |
CN105657238B (en) * | 2014-11-20 | 2017-09-19 | 广东欧珀移动通信有限公司 | Track focusing method and device |
CN104836954B (en) * | 2015-04-23 | 2017-11-17 | 深圳金三立视频科技股份有限公司 | Zoom tracking and its device |
CN105303807B (en) * | 2015-11-25 | 2018-04-10 | 深圳市大疆灵眸科技有限公司 | Remote control, moveable platform and its control method and system and unmanned vehicle |
CN205384727U (en) * | 2015-11-25 | 2016-07-13 | 深圳市大疆创新科技有限公司 | Remote controller, movable platform , movable platform system and unmanned vehicles |
CN105874384B (en) * | 2016-01-06 | 2019-07-16 | 深圳市莫孚康技术有限公司 | Based on a variety of distance measuring methods with burnt system, method and camera system |
-
2017
- 2017-11-16 CN CN201711137633.7A patent/CN107918278B/en active Active
Also Published As
Publication number | Publication date |
---|---|
CN107918278A (en) | 2018-04-17 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
WO2017181511A1 (en) | Terminal device and control system for unmanned aerial vehicle | |
US20150288857A1 (en) | Mount that facilitates positioning and orienting a mobile computing device | |
CN104010131B (en) | A kind of video camera is automatically with coke installation and method | |
CN108090838A (en) | Identify method, apparatus, server, client and the system of damaged vehicle component | |
CN104967785A (en) | Method and apparatus for controlling optical image stabilization | |
CN105676880A (en) | Control method and system of holder camera device | |
CN105488457A (en) | Virtual simulation method and system of camera motion control system in film shooting | |
CN104469168A (en) | Shooting module and automatic focusing method thereof | |
CN104951070A (en) | Method and device for manipulating device based on eyes | |
US20160117811A1 (en) | Method for generating a target trajectory of a camera embarked on a drone and corresponding system | |
CN107465877B (en) | Track focusing method and device and related media production | |
CN105550655A (en) | Gesture image obtaining device and method | |
WO2022126436A1 (en) | Delay detection method and apparatus, system, movable platform, and storage medium | |
CN105635555A (en) | Camera focusing control method, image pick-up device and wearable intelligent terminal | |
CN103856717A (en) | Camera focusing control method and device | |
CN101021604A (en) | Dynamic target automatic zooming system based on image processing | |
CN107918278B (en) | Automatic focus following method for film and television lens | |
WO2017117749A1 (en) | Follow focus system and method based on multiple ranging approaches, and photographing system | |
CN104767927A (en) | Orientation control method and device for holder camera | |
CN108038417A (en) | Cloud platform control method, apparatus and system | |
CN104778750A (en) | Facial expression capturing system and implementation method | |
CN104793643B (en) | A kind of three-dimensional stop motion animation camera system and control method | |
CN108989765A (en) | The tripod system of dynamically track self-timer | |
WO2022151473A1 (en) | Photographing control method, photographing control apparatus and gimbal assembly | |
WO2017117750A1 (en) | Simple follow focus system based on multiple ranging approaches, and photographing system |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant |