CN103973986A - Focusing and lens switching method based on mobile terminal camera - Google Patents

Abstract

The present invention relates to a method for focusing and lens switching based on a mobile terminal camera. The method includes: detecting whether a camera activation signal is received; It is transmitted to the central processing unit; the central processing unit compares the operation gesture with at least two gesture images stored in the database, and generates a focus instruction according to the comparison result and transmits it to the focus motor; And the focus motor controls the camera to focus according to the focus instruction. In this way, it is more convenient to control the camera of the mobile terminal to adjust the focus, thereby enhancing the user experience.

Description

A focusing and lens switching method based on a mobile terminal camera

technical field

The present invention relates to the technical field of mobile terminal cameras, in particular to a method for focusing and lens switching based on mobile terminal cameras.

Background technique

On mobile terminals such as smart phones, taking pictures has become an indispensable and important function, and most cameras on mobile terminals such as smart phones now have a focusing function. However, the focusing functions of cameras on existing smart phones and other mobile terminals are usually divided into the following types: 1. Focusing is performed through function buttons arranged on smart phones and other mobile terminals; A focus menu is displayed on the display screen of the mobile terminal, and the user adjusts the focus by clicking the focus menu;

To sum up, when focusing on the cameras of existing mobile terminals such as smartphones, users need to perform related operations on surfaces such as touch screens and display screens or press function buttons, that is, users must touch mobile phones such as smartphones when operating Terminal, therefore, it will be inconvenient to use when performing the above-mentioned focusing operation, and the user experience is not high. For example, when the user uses the camera of a mobile terminal such as a smart phone to take a selfie, if the camera is far away from the lens, it is difficult to perform mobile operations such as a smart phone. Focusing operation for terminal contacts.

Similarly, most mobile terminals such as smart phones now have a front camera and a rear camera. When switching between lenses, users also need to perform corresponding touch operations on the surface of the touch screen, which is inconvenient to operate when they are far away from the lens.

Therefore, in view of the fact that the traditional focusing method and its lens switching method need to be improved, the inventor actively aims at a mobile terminal camera based on his many years of creative design and professional manufacturing experience in related fields. Focusing and lens switching methods have been researched and improved, and the present invention has finally been developed after careful consideration of various conditions.

Contents of the invention

In order to solve the problems existing in the background technology, that is, in order to solve the inconvenient problem of focusing and lens switching of mobile terminal cameras in the prior art, and to find a more convenient and high-experience focusing and lens switching method, the present invention implements The example provides a method for focusing and lens switching based on a mobile terminal camera.

The embodiment of the present invention adopts the following technical solution: a focusing method based on a mobile terminal camera, the method comprising:

Detect whether a camera start signal is received;

If received, obtain the operation gesture performed by the user outside the mobile terminal and transmit it to the central processing unit;

The central processing unit compares the operation gesture with at least two gesture images stored in the database, and generates a focus instruction according to the comparison result and sends it to the focus motor; and

The focus motor controls the camera to perform focus according to the focus instruction.

Preferably, the acquisition of the operation gestures performed by the user outside the mobile terminal and sending them to the central processing unit includes:

Judging whether the received camera activation signal is a rear camera activation signal;

If so, start the front camera, obtain the user's operation gesture performed outside the mobile terminal and send it to the central processing unit; if not, continue to judge whether the camera start signal is a front camera start signal; and

If yes, start the rear camera to acquire the operation gestures performed by the user outside the mobile terminal and send them to the central processing unit.

Preferably, the at least two gesture images stored in the database include a dynamic image of the palm gradually moving towards the camera and a dynamic image of the palm gradually moving away from the camera.

Preferably, when the central processing unit compares that the operation gesture is a dynamic image of the palm gradually approaching the camera, the generated focusing instruction is to increase the focal length; when the central processing unit compares the operation When the gesture is a dynamic image in which the palm is gradually moving away from the camera, the generated focus instruction is to reduce the focus distance.

A focusing method based on a mobile terminal camera, the method comprising:

Detect whether a camera start signal is received;

If received, then turn on at least one infrared ranging sensor located on the surface of the mobile terminal to detect the distance change data from the user's operation gesture outside the mobile terminal to the surface of the mobile terminal and send it to the central processing unit;

The central processing unit will generate a focus command according to the distance change data and send it to the focus motor; and

The focus motor controls the camera to perform focus according to the focus instruction.

Preferably, when the distance variation data is in a decreasing state, the generated focusing instruction is to increase the focal length; when the distance variation data is in an increasing state, the generated focusing instruction is to reduce the focal length.

Preferably, the method also includes:

When the focus motor controls the focal length of the camera to be adjusted to the maximum, the central processing unit judges whether to continuously receive the distance change data in a decreasing state transmitted by the infrared distance measuring sensor; if received, then the CPU will not generate the focus instruction; and

When the focusing motor controls the focal length of the camera to be adjusted to the minimum, the central processing unit judges whether to continuously receive the distance change data in an increasing state transmitted by the infrared distance measuring sensor; if received, then The CPU will not generate the focus instruction.

A lens switching method based on a mobile terminal camera, the method comprising:

Detect whether a camera start signal is received;

If received, obtain the operation gesture performed by the user outside the mobile terminal and transmit it to the central processing unit;

The central processing unit compares the operation gesture with at least one gesture image stored in the database, and generates a camera switching command according to the comparison result and transmits it to the camera switching module; and

The lens switching module controls the camera to perform lens switching according to the lens switching instruction.

Preferably, the acquisition of the operation gestures performed by the user outside the mobile terminal and sending them to the central processing unit includes:

Judging whether the received camera activation signal is a rear camera activation signal;

If so, start the front camera, obtain the user's operation gesture performed outside the mobile terminal and send it to the central processing unit; if not, continue to judge whether the camera start signal is a front camera start signal; and

If yes, start the rear camera to acquire the operation gestures performed by the user outside the mobile terminal and send them to the central processing unit.

Preferably, at least one gesture image stored in the database is a dynamic image of palm turning.

The beneficial effects brought by the technical solution provided by the embodiments of the present invention are:

(1) In practice, when the user needs to focus the camera of the mobile terminal, he can place his hand outside the mobile terminal and perform the same gesture as any one of the at least two gesture images stored in the database. When the user gradually moves the palm towards the camera, the focus motor controls the camera to adjust the focal length according to the focus instruction; when the user moves the palm gradually away from the camera, the focus motor controls the camera to reduce the focus according to the focus instruction. In this way, it is more convenient to control the camera of the mobile terminal to adjust the focus, thereby enhancing the user experience.

(2) In practice, when the user needs to switch the camera lens of the mobile terminal, he can place his hand outside the mobile terminal and perform the same gesture as any one of at least one gesture image stored in the database. When the user When the palm is turned over, the lens switching module controls the camera to perform lens switching according to the lens switching instruction. In this way, it is more convenient to control the camera of the mobile terminal to switch between lenses, thereby enhancing user experience.

Description of drawings

In order to make the above-mentioned and other purposes, features and advantages of the present invention more obvious and understandable, the accompanying drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only the present invention. For some embodiments of the invention, those of ordinary skill in the art can also obtain other drawings based on these drawings without being creative.

FIG. 1 is a flowchart of a focusing method based on a mobile terminal camera provided in the first embodiment of the present invention;

FIG. 2 is a schematic diagram of a focusing method based on a mobile terminal camera provided by the first embodiment of the present invention;

FIG. 3 is another schematic diagram of a focusing method based on a mobile terminal camera provided in the first embodiment of the present invention;

FIG. 4 is a flowchart of a focusing method based on a mobile terminal camera provided by the second embodiment of the present invention;

FIG. 5 is a flow chart of a camera-based lens switching method of a mobile terminal according to a third embodiment of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

In the descriptions of the following embodiments, the present invention is only explained and illustrated by applying the focusing and lens switching methods to smartphones, but this is not intended to limit the present invention. Other terminals or devices can also be applied to the technical solution of the present invention. , the principle is basically the same as that of the smart phone, and will not be repeated in the embodiment of the present invention. And the mobile terminal includes, but is not limited to, a smart phone with a touch screen, a tablet computer, a netbook, a PDA (Portable Digital Assistant), an audio layer-4 (MP4) player, and the like.

first embodiment

Please refer to FIG. 1 . FIG. 1 is a flowchart of a focusing method based on a mobile terminal camera according to a first embodiment of the present invention. The first embodiment of the present invention provides a mobile terminal camera-based focusing method, the method includes the following steps:

Step S10, detecting whether a camera activation signal is received;

If received, step S11 is executed to obtain the operation gesture performed by the user outside the mobile terminal and transmit it to the central processing unit;

Step S12, the central processing unit compares the operation gesture with at least two gesture images stored in the database, and generates a focus instruction according to the comparison result and transmits it to the focus motor; and

Step S13, the focus motor controls the camera to perform focus according to the focus instruction.

Firstly, in the step S10, it is detected whether a camera activation signal is received, that is, it is detected whether the camera of the mobile phone is turned on by the user. When the detection receives the camera activation signal, execute the step S11; when the detection does not receive the camera activation signal, jump to the step S10 to continue detection.

Specifically, in the step S11, that is, in the acquisition of the operation gesture performed by the user outside the mobile terminal and transmitting it to the central processing unit, the following steps are specifically included:

Step S110, judging whether the received camera activation signal is a rear camera activation signal, that is, judging whether the turned on camera is a rear camera;

If so, then execute step S111, start the front camera, obtain the operation gesture performed by the user on the outside of the mobile terminal and send it to the central processing unit; if not, then execute step S112, continue to judge whether the camera activation signal Starting a signal for the front camera, that is, judging whether the camera that is turned on is a front camera; and

In the step S112, if it is judged that the camera activation signal is a front camera activation signal, step S113 is executed to activate the rear camera, obtain the operation gesture performed by the user on the outside of the mobile terminal and transmit it to the central Processor; if it is judged that the camera activation signal is not a front camera activation signal, jump to the step S110 to continue the judgment.

Further, in the step S12, the at least two gesture images stored in the database include a dynamic image of the palm gradually approaching the camera and a dynamic image of the palm gradually moving away from the camera, and in the first embodiment of the present invention, for The specific actions performed by the palm are not limited.

Therefore, the central processing unit compares the operation gesture with the dynamic image of the palm gradually approaching the camera and the dynamic image of the palm gradually moving away from the camera, and generates a focus command according to the comparison result and sends it to the focus motor.

Specifically, when the central processing unit compares that the operation gesture is a dynamic image of the palm gradually approaching the camera, the generated focusing instruction is to increase the focus distance, and when the central processing unit compares the operation When the gesture is a dynamic image in which the palm is gradually moving away from the camera, the generated focus instruction is to reduce the focus distance.

Further, if the activated camera is the rear camera, the front camera is used to obtain the user's operation gesture, so the user should place the palm in the corresponding direction of the front camera when performing the operation gesture, That is, the corresponding direction of the mobile phone screen; if the activated camera is the front camera, then the rear camera is used to obtain the user's operation gestures, so the user should place the palm of the hand on the rear camera when performing the operation gestures The corresponding direction of , that is, the corresponding direction of the rear case of the mobile phone.

In the step S13, that is, when the focus motor controls the camera to perform focus adjustment according to the focus adjustment instruction, it specifically includes: when receiving the focus adjustment instruction sent by the central processing unit as zooming in When the focal length is adjusted, the focus motor controls the camera to increase the focal length; similarly, when receiving the focus instruction sent by the central processing unit to reduce the focal length, the focus motor controls the camera The focal length is reduced, and the camera controlled and adjusted by the focusing motor is the camera that is currently turned on, not the camera used to acquire user gestures.

Please refer to FIG. 2 . FIG. 2 is a schematic diagram of a focusing method based on a mobile terminal camera according to a first embodiment of the present invention. Specifically, the camera start signal received is set as the rear camera start signal, that is, the camera that is turned on is the rear camera, and the one used to obtain the user's operation gesture is the front camera, as shown in FIG. 2 , When the user's palm is above the screen of the mobile phone, if it remains stationary, the operation gestures performed by the user obtained by the front camera do not conform to any one of the at least two gesture images stored in the database, that is, it is not for the The dynamic image of the palm gradually moving towards the camera is not the same as the dynamic image of the palm gradually moving away from the camera. When the user's palm moves down, that is, when it moves towards the direction of the mobile phone screen, the downward movement generated by it, that is, the operation gesture conforms to the dynamic image of the palm gradually moving towards the camera, and the central processing unit sends a call The focusing command of large focal length is given to the focusing motor, and the focusing motor controls the camera to increase the focal length; operation, that is, the operation gesture is in line with the dynamic image of the palm gradually moving away from the camera, then the central processing unit sends a focus instruction for reducing the focus distance to the focus motor, and the focus motor controls the camera to adjust small focal length.

Please refer to FIG. 3 . FIG. 3 is another schematic diagram of a focusing method based on a mobile terminal camera provided by the first embodiment of the present invention. Specifically, the camera activation signal received is set as the front camera activation signal, that is, the camera that is turned on is the front camera, and the camera that is used to obtain the user's operation gesture is the rear camera, as shown in FIG. 3 , When the user's palm is located under the back shell of the mobile phone, if it remains stationary, the operation gestures performed by the user acquired by the rear camera do not conform to any of the at least two gesture images stored in the database, that is, it is not acceptable. The dynamic image of the palm gradually moving towards the camera is not the same as the dynamic image of the palm gradually moving away from the camera. When the user's palm moves up, that is, when it moves towards the direction of the back shell of the mobile phone, the upward movement generated by it, that is, the operation gesture conforms to the dynamic image of the palm gradually moving towards the camera, and the central processing unit transmits The focusing command for increasing the focal length is given to the focusing motor, and the focusing motor controls the camera to increase the focal length; Moving down, that is, the operation gesture is consistent with the dynamic image that the palm is gradually moving away from the camera, then the central processing unit sends a focus instruction for reducing the focus distance to the focus motor, and the focus motor controls the The camera zooms out.

second embodiment

Please refer to FIG. 4 . FIG. 4 is a flowchart of a focusing method based on a mobile terminal camera according to a second embodiment of the present invention. In the second embodiment of the present invention, a method for focusing based on a mobile terminal camera is further provided, and the method includes the following steps:

Step S20, detecting whether a camera activation signal is received;

If it is received, then execute step S21, turn on at least one infrared distance measuring sensor located on the surface of the mobile terminal to detect the distance change data from the user's operation gesture outside the mobile terminal to the surface of the mobile terminal and send it to CPU;

Step S22, the central processing unit generates a focus instruction according to the distance change data and sends it to the focus motor; and

Step S23, the focus motor controls the camera to perform focus according to the focus instruction.

Firstly, in the step S20, it is detected whether a camera activation signal is received, that is, it is detected whether the camera of the mobile phone is turned on by the user. When the detection receives the camera activation signal, execute the step S21; when the detection does not receive the camera activation signal, jump to the step S20 to continue detection.

Specifically, in the step S21, after turning on at least one infrared distance measuring sensor arranged on the surface of the mobile terminal to detect the distance change data from the user's operation gesture outside the mobile terminal to the surface of the mobile terminal And send it to the central processing unit, specifically including the following steps:

Step S210, judging whether the received camera activation signal is a rear camera activation signal, that is, judging whether the turned-on camera is a rear camera;

If yes, execute step S211, turn on at least one infrared distance measuring sensor on the same surface as the rear camera to detect the distance change data from the user's operation gesture outside the mobile terminal to the surface of the mobile terminal and send it to Central processing unit; if not, then execute step S212, continue to determine whether the camera activation signal is a front camera activation signal, that is, determine whether the opened camera is a front camera; and

In the step S212, if it is judged that the camera activation signal is a front camera activation signal, step S213 is executed to turn on at least one infrared distance measuring sensor on the same surface as the front camera to detect the The distance change data from the operation gesture outside the mobile terminal to the surface of the mobile terminal is sent to the central processing unit; if it is judged that the camera activation signal is not a front camera activation signal, then jump to the step S210 to continue the judgment.

Further, in the second embodiment of the present invention, at least one infrared ranging sensor on the same surface as the rear camera can be specifically arranged on the surface of the rear casing of the mobile terminal, that is, on the side opposite to the screen; The at least one infrared ranging sensor with the camera on the same surface can be specifically arranged on the screen surface, that is, integrated with the screen surface, or in the vicinity of the front camera, that is, near the top of the mobile terminal screen, in the present invention In the second embodiment, the latter may be preferred but not limited to.

Taking a mobile phone as an example, if the activated camera is a rear camera, the distance change data used to detect the user's operation gesture outside the mobile terminal to the surface of the mobile terminal is the one on the same surface as the rear camera. The at least one infrared ranging sensor, so the user should place the palm in the corresponding direction of the rear camera when performing the operation gesture, that is, the corresponding direction of the rear shell of the mobile phone; if the camera to be started is a front camera, then The at least one infrared ranging sensor on the same surface as the front camera is used to detect the distance change data from the user's operation gesture outside the mobile terminal to the surface of the mobile terminal, so the user is performing the operation. When performing the above operation gestures, the palm should be placed in the corresponding direction of the front camera, that is, the corresponding direction of the mobile phone screen.

In the step S22, when the distance change data detected by the at least one infrared distance measuring sensor is in a decreasing state, the generated focusing command is to increase the focal length; when the distance change data is in an increasing state , the generated focusing instruction is to reduce the focal length.

Specifically, when the distance change data is in a decreasing state, the corresponding operation gesture is that the palm is gradually moving towards the infrared distance measuring sensor; when the distance change data is in an increasing state, the corresponding operation gesture is that the palm is gradually moving away from the infrared sensor distance sensor.

Further, in the step S23, when receiving the focusing instruction sent by the at least one infrared distance measuring sensor as increasing the focal length, the focusing motor controls the camera to increase the focal length; similarly, When receiving the focusing instruction sent by the central processing unit to reduce the focus distance, the focus motor controls the camera to reduce the focus distance.

Further, in the second embodiment of the present invention, the method further includes:

When the focus motor controls the focal length of the camera to be adjusted to the maximum, the central processing unit judges whether to continuously receive the distance change data in a decreasing state transmitted by the infrared distance measuring sensor; if received, then the CPU will not generate the focus instruction; and

When the focusing motor controls the focal length of the camera to be adjusted to the minimum, the central processing unit judges whether to continuously receive the distance change data in an increasing state transmitted by the infrared distance measuring sensor; if received, then The CPU will not generate the focus instruction.

Further, if when the focus motor controls the focus of the camera to be adjusted to the maximum, the central processing unit continues to receive the distance change data in an incremental state transmitted by the infrared distance measuring sensor, then the The central processing unit generates the focusing instruction; similarly, if the focusing motor controls the focal length of the camera to be adjusted to the minimum, the central processing unit continues to receive the information transmitted by the infrared distance measuring sensor in a decreasing If the distance variation data of the state is not obtained, the central processing unit generates the focusing instruction.

third embodiment

Please refer to FIG. 5 . FIG. 5 is a flowchart of a camera-based lens switching method of a mobile terminal according to a third embodiment of the present invention. In the third embodiment of the present invention, a lens switching method based on a mobile terminal camera is further provided, wherein the method includes the following steps:

Step S30, detecting whether a camera activation signal is received;

If received, step S31 is executed to obtain the operation gesture performed by the user outside the mobile terminal and transmit it to the central processing unit;

Step S32, the central processing unit compares the operation gesture with at least one gesture image stored in the database, and generates a camera switching instruction according to the comparison result and transmits it to the camera switching module; and

Step S33, the lens switching module controls the camera to perform lens switching according to the lens switching instruction.

Firstly, in the step S30, it is detected whether a camera start signal is received, that is, whether the camera of the mobile phone is turned on by the user. When the detection receives the camera activation signal, execute the step S31; when the detection does not receive the camera activation signal, jump to the step S30 to continue detection.

Specifically, in the step S31, that is, in the acquisition of the operation gesture performed by the user outside the mobile terminal and transmitting it to the central processing unit, the following steps are specifically included:

Step S310, judging whether the received camera activation signal is a rear camera activation signal, that is, judging whether the turned-on camera is a rear camera;

If so, then execute step S311, start the front camera, obtain the operation gesture performed by the user on the outside of the mobile terminal and send it to the central processing unit; if not, then execute step S312, continue to judge whether the camera activation signal Starting a signal for the front camera, that is, judging whether the camera that is turned on is a front camera; and

In the step S312, if it is judged that the camera activation signal is a front camera activation signal, step S313 is executed to activate the rear camera, obtain the operation gesture performed by the user outside the mobile terminal and transmit it to the central Processor; if it is determined that the camera activation signal is not a front camera activation signal, jump to the step S310 to continue the determination.

Further, in the step S32, at least one gesture image stored in the database is a dynamic image of palm turning.

Therefore, the central processing unit compares the operation gesture with the dynamic image of palm flipping, generates a camera switching instruction according to the comparison result, and sends it to the camera switching module.

Specifically, when the central processing unit compares the dynamic image in which the operation gesture is palm flipping, it will generate a camera switching command and send it to the camera switching module.

Further, if the activated camera is the rear camera, the front camera is used to obtain the user's operation gesture, so the user should place the palm in the corresponding direction of the front camera when performing the operation gesture, That is, the corresponding direction of the mobile phone screen; if the activated camera is the front camera, then the rear camera is used to obtain the user's operation gestures, so the user should place the palm of the hand on the rear camera when performing the operation gestures The corresponding direction of , that is, the corresponding direction of the rear case of the mobile phone.

In the step S33, that is, when the lens switching module controls the camera to perform lens switching according to the lens switching instruction, it specifically includes: when receiving the lens switching instruction transmitted by the central processing unit, then The lens switching module controls the camera to perform lens switching according to the lens switching instruction.

The present invention can realize following advantage:

With the present invention, when the user needs to focus the camera of the mobile terminal, he can place his hand outside the mobile terminal and perform the same gesture as any one of the at least two gesture images stored in the database. When gradually approaching the camera, the focus motor controls the camera to increase the focal length according to the focus instruction; when the user moves the palm away from the camera gradually, the focus motor controls the camera to reduce the focus according to the focus instruction. In this way, it is more convenient to control the camera of the mobile terminal to adjust the focus, thereby enhancing the user experience.

When the user needs to switch the camera lens of the mobile terminal, by placing the hand outside the mobile terminal and performing the same gesture as any one of at least one gesture image stored in the database, when the user turns the palm over, the lens The switching module controls the camera to perform lens switching according to the lens switching instruction. In this way, it is more convenient to control the camera of the mobile terminal to switch between lenses, thereby enhancing user experience.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present invention. Should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the said claims.

Claims (10)

1. A focusing method based on a mobile terminal camera, characterized in that the method comprises: Detect whether the camera start signal is received; If received, obtain the operation gesture performed by the user outside the mobile terminal and transmit it to the central processing unit; The central processing unit compares the operation gesture with at least two gesture images stored in the database, and generates a focus instruction according to the comparison result and sends it to the focus motor; and The focus motor controls the camera to perform focus according to the focus instruction. 2. A method for adjusting focus based on a mobile terminal camera as claimed in claim 1, wherein said obtaining the operation gesture performed by the user outside the mobile terminal and transmitting it to the central processing unit comprises: Judging whether the received camera activation signal is a rear camera activation signal; If so, start the front camera, obtain the user's operation gesture performed outside the mobile terminal and send it to the central processing unit; if not, continue to judge whether the camera start signal is a front camera start signal; and If yes, start the rear camera to acquire the operation gestures performed by the user outside the mobile terminal and send them to the central processing unit. 3. A kind of focusing method based on mobile terminal camera as claimed in claim 1, is characterized in that, at least two gesture images stored in the database include the dynamic image of the palm gradually moving towards the camera and the image of the palm gradually moving away from the camera. dynamic image. 4. A kind of focusing method based on mobile terminal camera as claimed in claim 3, it is characterized in that, when described central processing unit compares described operation gesture to be the dynamic image that described palm gradually tends toward camera, generates The focus adjustment instruction is to increase the focus distance; when the central processing unit compares the operation gesture as a dynamic image in which the palm gradually moves away from the camera, the generated focus adjustment instruction is to decrease the focus distance. 5. A focusing method based on a mobile terminal camera, characterized in that the method comprises: Detect whether the camera start signal is received; If received, then turn on at least one infrared ranging sensor located on the surface of the mobile terminal to detect the distance change data from the user's operation gesture outside the mobile terminal to the surface of the mobile terminal and send it to the central processing unit; The central processing unit will generate a focus command according to the distance change data and send it to the focus motor; and The focus motor controls the camera to perform focus according to the focus instruction. 6. A kind of focusing method based on mobile terminal camera as claimed in claim 5, it is characterized in that, when the distance variation data is in a decreasing state, the generated focus instruction is to increase the focal length; when the distance variation When the data is increasing, the generated focusing instruction is to reduce the focal length. 7. A kind of focusing method based on mobile terminal camera as claimed in claim 6, is characterized in that, described method also comprises: When the focus motor controls the focal length of the camera to be adjusted to the maximum, the central processing unit judges whether to continuously receive the distance change data in a decreasing state transmitted by the infrared distance measuring sensor; if received, then the CPU will not generate the focus instruction; and When the focusing motor controls the focal length of the camera to be adjusted to the minimum, the central processing unit judges whether to continuously receive the distance change data in an increasing state transmitted by the infrared distance measuring sensor; if received, then The CPU will not generate the focus instruction. 8. A lens switching method based on a mobile terminal camera, characterized in that the method comprises: Detect whether a camera start signal is received; If received, obtain the operation gesture performed by the user outside the mobile terminal and transmit it to the central processing unit; The central processing unit compares the operation gesture with at least one gesture image stored in the database, and generates a camera switching command according to the comparison result and transmits it to the camera switching module; and The lens switching module controls the camera to perform lens switching according to the lens switching instruction. 9. A method for switching lenses based on a mobile terminal camera as claimed in claim 8, wherein said obtaining the operation gesture performed by the user outside the mobile terminal and transmitting it to the central processing unit comprises: Judging whether the received camera activation signal is a rear camera activation signal; If so, start the front camera, obtain the user's operation gesture performed outside the mobile terminal and send it to the central processing unit; if not, continue to judge whether the camera start signal is a front camera start signal; and If yes, start the rear camera to acquire the operation gestures performed by the user outside the mobile terminal and send them to the central processing unit. 10. A camera-based lens switching method of a mobile terminal according to claim 8, wherein at least one gesture image stored in the database is a dynamic image of palm flipping.