WO2021139502A1

WO2021139502A1 - Human eye protection method for projector, and projector

Info

Publication number: WO2021139502A1
Application number: PCT/CN2020/137105
Authority: WO
Inventors: 宋起涛; 李艳波
Original assignee: 深圳光峰科技股份有限公司
Priority date: 2020-01-08
Filing date: 2020-12-17
Publication date: 2021-07-15
Also published as: CN113099194A

Abstract

Disclosed are a human eye protection method for a projector, and a projector. The human eye protection method comprises: acquiring first image information that is output by a projector and second image information that is projected and displayed on a projection screen corresponding to the projector at the same moment; comparing the first image information with the second image information so as to determine a dark field region; carrying out, according to the dark field region, dark field processing on an image received by the projector, so that the brightness of a portion, corresponding to the dark field region, in an image output by the projector is lower than a brightness threshold value. By means of the human eye protection method for a projector provided in the present application, the eyesight of a user can be protected without affecting a projection effect.

Description

Eye protection method for projector and projector

Technical field

This application relates to the technical field of projectors, and in particular to a method for protecting eyes of a projector and a projector.

Background technique

A projector, also known as a projector, is a device that can project images or videos onto a screen. At present, it has been extremely widely used in various occasions, such as various meeting places, classrooms, and so on.

The inventor of the present application found that the current beam emitted by the projector is likely to cause damage to the user’s vision. Specifically, when the user walks into the projection area, the user’s eyes will be stabbed by the beam emitted by the projector, even if the user walks out behind. The projection area is also difficult to restore vision in a short time.

At present, in view of the above-mentioned defects of the projector, the existing common practice is to turn off the light source of the projector when it detects that there is an obstruction in the projection field of the projector. However, this approach also has the following defects: when the obstruction is not the user , Turning off the light source of the projector will affect the display effect and reduce the user experience.

Summary of the invention

The main technical problem to be solved by this application is to provide a method for protecting eyes of a projector and the projector, which can protect the eyesight of the viewer without affecting the projection effect.

In order to solve the above technical problems, a technical solution adopted in this application is to provide a method for protecting eyes of a projector, the method for protecting eyes includes: acquiring first image information output by the projector at the same time and The second image information projected and displayed on the projection screen corresponding to the projector; compare the first image information and the second image information to determine a dark field area; receive the projector according to the dark field area Dark field processing is performed on the image of, so that the brightness of the portion corresponding to the dark field area in the image output by the projector is less than the brightness threshold.

In order to solve the above technical problems, another technical solution adopted in this application is to provide a projector, including a communication circuit and a processor coupled to it, the communication circuit being used to obtain the first image output by the projector at the same time Information and the second image information projected and displayed on the projection screen corresponding to the projector, the processor is used to compare the first image information and the second image information to determine the dark field area, and further according to the The dark field area performs dark field processing on the image received by the projector, so that the brightness of the part corresponding to the dark field area in the image output by the projector is less than a brightness threshold.

The beneficial effect of the present application is that the eye protection method used for the projector of the present application first obtains the first image information output by the projector at the same time and the second image information projected and displayed on the projection screen, and then compares the first image information and the second image information. 2. Determine the dark field area based on the image information, and finally perform dark field processing on the image received by the projector according to the dark field area, so that the brightness of the corresponding dark field area in the image output by the projector is less than the first brightness threshold. Specifically, the The method can ensure that the brightness of the image finally projected on the obstruction is less than the first brightness threshold by performing dark field processing on the image received by the projector, so that when the obstruction is the user, the light emitted by the projector can prevent the user from damaging his vision.

Description of the drawings

In order to more clearly describe the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings that need to be used in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work. among them:

Fig. 1 is a schematic diagram of the structure of a projection system in the prior art;

2 is a schematic flowchart of an embodiment of the human eye protection method for a projector according to the present application;

Fig. 3 is a schematic structural diagram of an embodiment of a projector according to the present application;

4 is a schematic structural diagram of another embodiment of the projector of the present application;

Fig. 5 is a schematic structural diagram of an embodiment of the computer-readable storage medium of the present application.

Detailed ways

The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of this application.

In the prior art, as shown in FIG. 1, the projection system 100 includes a projector 110 and a corresponding projection screen 120. When the projection system 100 is working, the projector 110 will receive an image or video from a playback source. It is projected onto the corresponding projection screen 120, and the rear projection screen 120 displays.

The eye protection method for projectors in this application can be used on any type of projector 110 in the prior art, such as CRT (Cathode Ray Tube, cathode ray tube) projectors, LCD (Liquid Crystal Display, Liquid crystal display) projector, DLP (Digital Light Processing, digital light processing technology) projector, or LCOS (Liquid Crystal On Silicon, liquid crystal on silicon) projector, etc.

With reference to Figure 1 and Figure 2, the eye protection method for a projector includes:

S110: Obtain the first image information output by the projector 110 and the second image information projected and displayed on the projection screen 120 corresponding to the projector 110 at the same time.

Wherein, the executor of the human eye protection method for a projector in this embodiment is the projector 110.

The first image information and the second image information are respectively the image information of the image output by the projector 110 and the image information of the image projected and displayed on the projection screen 120 at the same time.

In this embodiment, the projector 110 includes a camera, and the second image projected and displayed on the projection screen 120 is captured by the camera to obtain the second image information.

S120: Compare the first image information and the second image information to determine a dark field area.

When there is no obstruction in the projection field of the projector 110, at the same moment, the first image output by the projector 110 is exactly the same as the second image projected and displayed on the projection screen 120, so the acquired first image information is the same as the first image. The two image information is exactly the same; and when there is an obstruction in the projection field of the projector 110, at the same moment, due to the obstruction of the obstruction, the second image has a dark field area compared to the first image. It can be understood that, The dark field area is the projection of the obstruction on the projection screen 120. At this time, the dark field area can be determined by comparing the first image information and the second image information.

S130: Perform dark field processing on the image received by the projector 110 according to the dark field area, so that the brightness of the portion of the image output by the projector 110 corresponding to the dark field area is less than the brightness threshold.

It is understandable that when the image received by the projector 110 is not subjected to dark field processing, the final image output by the projector 110 and the image received by the projector 110 are the same image, that is, when the dark field processing is not performed, the projector 110 finally The output image is the image corresponding to the first image information.

Performing dark field processing on the image received by the projector 110 according to the dark field area refers to reducing the brightness of the portion of the image received by the projector 110 corresponding to the dark field area, so that the brightness at the corresponding dark field area is less than the brightness threshold, so that the projector The brightness of the part corresponding to the dark field area of the 110 output image will be less than the brightness threshold, so the brightness of the image projected on the obstruction will be less than the brightness threshold. When the obstruction is the user, it can prevent the light emitted by the projector from damaging it. vision.

It is understandable that due to the occlusion of the obstruction, even if dark field processing is not performed on the image received by the projector 110, the image displayed by the projection screen 120 will have a shadow corresponding to the dark field area, so the image received by the projector 110 is processed The dark field processing does not adversely affect the content of the normal projection, that is, the method of the present application can protect the eyesight of the user without affecting the projection effect.

In step S130, performing dark field processing on the image received by the projector 110 refers to performing dark field processing on the image originally output by the projector 110 at the next moment. It can be understood that the image received by the projector 110 at the next moment is originally to be output. The image is determined by the playback source, and may be the same image as the previously output image, or it may be different.

The brightness threshold can be preset by the designer. For example, the designer can obtain a brightness threshold according to a large number of experiments in advance. When the brightness of the image projected to the user's eyes does not exceed the brightness threshold, the user has no obvious feeling, and when it exceeds At this brightness threshold, the user feels dazzling and glare.

In an application scenario, regardless of the content of the original image received by the projector 110, after dark field processing is performed on the image, the color of the image output by the projector 110 corresponding to the dark field area is gray or black.

At the same time, in this embodiment, in order to reduce unnecessary processing procedures, the premise of obtaining the first image information and the second image information in step S110 is that there are obstructions in the projection field of the projector 110. At this time, detection will be performed before step S110. It is measured whether there is an obstruction in the projection field of view of the projector 110. If it is detected that there is an obstruction in the projection view of the projector 110, step S110 is executed; otherwise, dark field processing is not performed on the image received by the projector 110.

In an application scenario, an infrared sensor is used to detect whether there is an obstruction in the projection field of view of the projector 110. In other words, the projector 110 also includes an infrared sensor. Wherein, in other embodiments, in order to avoid errors in determining whether there is an obstruction in the projection field of view of the projector 110 and resulting in omission, at this time, it is not necessary to determine whether there is an obstruction in the projection field of view of the projector 110, specifically Specifically, step S110 may be to obtain the first image information and the second image information in real time, or to obtain the first image information and the second image information at a certain time interval, for example, the time interval is 30 seconds, 1 minute, or 2 minutes. Wait.

It is understandable that not all occluders are the user's face, and when the occluders are other parts of the user or the occluders are not the user, at this time, if the image received by the projector 110 is also subjected to dark field processing, then It is meaningless. Therefore, in this embodiment, in order to further reduce unnecessary processing procedures, dark field processing is performed on the image received by the projector 110 only when the obstructing object is a human face.

In an application scenario, when it is detected that there is a occlusion in the projection field of the projector 110, it is immediately determined whether the occlusion is a human face, and only when the occlusion is a human face, step S110 is executed. In another application scene After determining the dark field area, it is possible to determine whether the occluder is a human face. Only when the occluder is a human face, step S130 is executed. In short, this application only needs to determine the occlusion before performing dark field processing on the image received by the projector 110. Whether the object is a human face is sufficient, and the specific timing of the judgment is not limited.

Wherein, in this embodiment, the step of determining whether the obstruction is a human face includes:

A1: Use the image edge detection technology to process the second image information projected and displayed on the projection screen 120 to determine whether the obstructing object is a human head.

A2: When it is determined that the obstruction is a human head, image feature extraction and recognition technology is used to process the second image information displayed on the projection screen 120 to further determine whether the obstruction is a human face.

First, the image edge detection technology is used to extract the outline of the obstruction from the second image projected and displayed on the projection screen 120, and according to the outline, it can be determined whether the obstruction is a human head; when it is determined that the obstruction is a human head, the image feature extraction and Recognition technology recognizes whether the obstruction is a human face.

Among them, in other embodiments, as long as it is determined that the occluder is a human head, the occluder may be determined to be a human face. That is to say, in the process of determining whether the occluder is a human face, only the image edge detection technology may be used. There is no need for subsequent image feature extraction and recognition technology processing.

Meanwhile, in this embodiment, the first image information is a first image matrix, and the second image information is a second image matrix.

In this case, step S120 specifically includes:

B1: Calculate the difference between the second image matrix and the first image matrix to obtain the dark field matrix.

Step S130 specifically includes:

C1: Set the data whose value is less than the numerical threshold value in the dark field matrix to 0, and set the data whose value is greater than or equal to the numerical threshold value to 1, and then obtain the normalized dark field matrix.

C2: Perform an AND operation on the image matrix of the image received by the projector 110 and the normalized dark field matrix to implement dark field processing on the image received by the projector 110.

In order to better understand the above steps, the specific process of dark field processing will be introduced below in conjunction with mathematical expressions.

_{First, the first image matrix I 1} of the first image output by the projector 110 _{and the second image matrix I 2} of the second image projected and displayed on the projection screen 120 are acquired.

Then, the difference between the second image matrix I ₂ and the first image matrix I ₁ is calculated to obtain the dark field matrix M. The calculation formula is: M=I ₂ -I ₁ .

Then a numerical threshold T is set to normalize the dark field matrix M. Specifically, the data in the dark field matrix M that is smaller than the numerical threshold T are set to 0, and the data that is greater than or equal to the numerical threshold T is set to 1. Thus, the normalized dark field matrix M'is obtained, that is, M'=normalization(M).

Finally, the image matrix of the image received by the projector 110 and the normalized dark field matrix M'are ANDed to obtain the final image matrix of the image to be output by the projector 110, thereby implementing dark field processing on the image received by the projector 110 .

In other embodiments, it is not necessary to first determine whether the occluder is a human face, but to subsequently determine whether the occluder is a human face based on the comparison result of the first image information and the second image information, and if it is determined to be a human face, then follow up If it is not a human face, then no subsequent dark field processing will be performed.

Specifically, at this time, the distribution of non-zero values in the dark field matrix M can be calculated to determine whether the obstruction is a human face.

Refer to FIG. 3, which is a schematic structural diagram of an embodiment of the projector of the present application. The projector 300 includes a communication circuit board 310 and a processor 320 coupled to it.

The communication circuit 310 is used to obtain the first image information output by the projector 300 and the second image information projected and displayed on the projection screen corresponding to the projector 300 at the same time; the processor 320 is used to compare the first image information and the second image information To determine the dark field area, the processor 320 is further configured to perform dark field processing on the image received by the projector 300 according to the dark field area, so that the brightness of the corresponding dark field area in the image output by the projector 300 is less than the brightness threshold.

In an application scenario, as shown in FIG. 3, the projector 300 includes a camera 330, which is coupled to the communication circuit 310, and the camera 330 is used to photograph the projection screen, so that the communication circuit 310 obtains the second projected display on the projection screen. 2. Image information.

Continuing to refer to FIG. 3, the projector 300 further includes: an infrared sensor 340.

The infrared sensor 340 is coupled with the communication circuit 310 for detecting whether there is an obstruction in the projection field of the projector 300, and the communication circuit 310 is further used for when the infrared sensor 340 detects that there is an obstruction in the projection field of the projector 300, The first image information output by the projector 300 and the second image information projected and displayed on the projection screen at the same time are acquired.

In this embodiment, the processor 320 is also used to determine whether the obstruction is a human face, and if the determination result is yes, the processor 320 performs dark field processing on the image received by the projector 300 according to the dark field area.

In this embodiment, the processor 320 is also configured to use image edge detection technology to process the second image information projected and displayed on the projection screen to determine whether the obstruction is a human head. At the same time, when it is determined that the obstruction is a human head, the processor 320 uses The image feature extraction and recognition technology processes the second image information displayed on the projection screen to further determine whether the obstruction is a human face.

In this embodiment, the first image information is a first image matrix, and the second image information is a second image matrix; the processor 320 is configured to calculate the difference between the second image matrix and the first image matrix to obtain the dark field matrix, Then the data in the dark field matrix whose value is less than the numerical threshold is set to 0, and the data whose value is greater than or equal to the numerical threshold is set to 1, and then the normalized dark field matrix is obtained. Finally, the image matrix of the image received by the projector 300 Performing an AND operation with the normalized dark field matrix realizes dark field processing on the image received by the projector 300.

The projector 300 in this embodiment executes the steps in the human eye protection method in any one of the above embodiments. For the detailed method, please refer to the above embodiment, which will not be repeated here.

Refer to FIG. 4, which is a schematic structural diagram of another embodiment of a projector 400 of the present application. In this embodiment, the projector 400 includes an image acquisition module 410, a dark field calculation module 420, and a dark field processing module 430.

The image acquisition module 410 is configured to acquire the first image information output by the projector 400 and the second image information projected and displayed on the projection screen corresponding to the projector 400 at the same time.

The dark field calculation module 420 is coupled to the image acquisition module 410, and is used to compare the first image information and the second image information to determine the dark field area.

The dark field processing module 430 is coupled to the dark field calculation module 420, and is used to perform dark field processing on the image received by the projector 400 according to the dark field area, so that the brightness of the corresponding dark field area in the image output by the projector 400 is less than the brightness Threshold.

In an application scenario, the image acquisition module 410 includes a camera for shooting a projection screen, so as to acquire the second image information projected and displayed on the projection screen.

In this embodiment, the projector 400 further includes an infrared detection module 440.

The infrared detection module 440 is coupled to the image acquisition module 410 for detecting whether there is an obstruction in the projection field of the projector 400; when the infrared detection module 440 detects that there is an obstruction in the projection field of the projector 400, the image is acquired The module 410 obtains the first image information output by the projector 400 and the second image information projected and displayed on the projection screen corresponding to the projector 400 at the same time.

In this embodiment, the projector 400 further includes a face detection module 450.

The face detection module 450 is coupled to the infrared detection module 440, and is used to determine whether the obstruction is a face; when the face detection module 450 determines that the obstruction is a face, the dark field processing module 430 receives the information from the projector 400 according to the dark field area. The image undergoes dark field processing.

Wherein, the face detection module 450 is specifically configured to use image edge detection technology to process the second image information projected and displayed on the projection screen, and then determine whether the obstructing object is a human head;

When it is determined that the obstructing object is a human head, image feature extraction and recognition technology is used to process the second image information displayed on the projection screen to further determine whether the obstructing object is a human face.

In this embodiment, the first image information is a first image matrix, and the second image information is a second image matrix; the dark field calculation module 420 calculates the difference between the second image matrix and the first image matrix to obtain the dark field matrix; The dark field processing module 430 sets the data in the dark field matrix whose value is less than the numerical threshold value to 0, and sets the data whose value is greater than or equal to the numerical threshold value to 1, thereby obtaining the normalized dark field matrix; at the same time, the dark field processing module 430 The image matrix of the image received by the projector 400 and the normalized dark field matrix are ANDed to implement dark field processing on the image received by the projector 400.

The projector 400 in this embodiment executes the steps in the human eye protection method in any one of the above embodiments. For details, please refer to the above embodiment, which will not be repeated here.

Refer to FIG. 5, which is a schematic structural diagram of an embodiment of the computer-readable storage medium of the present application. The computer-readable storage medium 500 includes instructions 510. When the instructions 510 are executed on a computer, the computer executes any of the above-mentioned methods. For detailed methods, please refer to the above-mentioned embodiments, which will not be repeated here.

The computer-readable storage medium 500 may be various devices such as a server, a USB flash drive, a mobile hard disk, a read-only memory (ROM, Random Access Memory), a random access memory (RAM), a magnetic disk, or an optical disk.

The above are only implementations of this application, and do not limit the scope of this application. Any equivalent structure or equivalent process transformation made using the content of the description and drawings of this application, or directly or indirectly applied to other related technologies In the same way, all fields are included in the scope of patent protection of this application.

Claims

A human eye protection method for a projector, characterized in that the human eye protection method includes:

Acquiring the first image information output by the projector and the second image information projected and displayed on the projection screen corresponding to the projector at the same time;

Comparing the first image information and the second image information to determine a dark field area;

Perform dark field processing on the image received by the projector according to the dark field area, so that the brightness of the portion corresponding to the dark field area in the image output by the projector is less than a brightness threshold.
The eye protection method according to claim 1, wherein the first image information output by the projector and the second image information projected and displayed on the projection screen corresponding to the projector at the same time of the acquisition Before, it also included:

Detecting whether there are obstructions in the projection field of view of the projector;

If it is detected that the obstruction is present in the projection field of view of the projector, the acquisition of the first image information output by the projector at the same time and the first image information projected and displayed on the projection screen corresponding to the projector is executed. 2. The steps of image information.
The method for protecting human eyes according to claim 2, wherein before the dark field processing is performed on the image received by the projector according to the dark field area, the method further comprises:

Judging whether the occluder is a human face;

If the result of the determination is yes, execute the step of performing dark field processing on the image received by the projector according to the dark field area.
The method for protecting human eyes according to claim 3, wherein the step of judging whether the obstructing object is a human face comprises:

Processing the second image information projected and displayed on the projection screen by using image edge detection technology to determine whether the obstruction is a human head;

When it is determined that the obstruction is a human head, image feature extraction and recognition technology is used to process the second image information displayed on the projection screen to further determine whether the obstruction is a human face.
The human eye protection method according to claim 1, wherein the first image information is a first image matrix, and the second image information is a second image matrix;

The step of comparing the first image information and the second image information to determine a dark field area includes:

Calculating the difference between the second image matrix and the first image matrix to obtain a dark field matrix;

The step of performing dark field processing on the image received by the projector according to the dark field area so that the brightness of the portion of the image output by the projector corresponding to the dark field area is less than a brightness threshold includes:

Set data in the dark field matrix with a value less than a numerical threshold to 0, and set data with a value greater than or equal to the numerical threshold to 1, to obtain a normalized dark field matrix;

The image matrix of the image received by the projector and the normalized dark field matrix are ANDed to implement dark field processing on the image received by the projector.
A projector, characterized by comprising a coupled communication circuit and a processor, the communication circuit is used to obtain the first image information output by the projector at the same time and the projection screen corresponding to the projector The second image information displayed, the processor is used to compare the first image information and the second image information to determine a dark field area, and further darken the image received by the projector according to the dark field area Field processing, so that the brightness of the part corresponding to the dark field area in the image output by the projector is less than a brightness threshold.
The projector according to claim 6, wherein the projector further comprises:

The infrared sensor is coupled with the communication circuit, and is used to detect whether there is an obstruction in the projection field of view of the projector, and the communication circuit is further used to detect the memory of the projection field of the projector when the infrared sensor detects In the case of the obstruction, the first image information output by the projector and the second image information projected and displayed on the projection screen at the same time are acquired.
The projector according to claim 7, wherein the processor is further configured to determine whether the obstruction is a human face, and if the result of the determination is yes, the processor performs a check on the The image received by the projector undergoes dark field processing.
The projector according to claim 8, wherein the processor is further configured to use image edge detection technology to process the second image information projected and displayed on the projection screen to determine whether the obstruction is Human head, and when it is determined that the obstructing object is a human head, the processor uses image feature extraction and recognition technology to process the second image information displayed on the projection screen to further determine whether the obstructing object is a human face.
The projector according to claim 6, wherein the first image information is a first image matrix, and the second image information is a second image matrix;

The processor is configured to calculate the difference between the second image matrix and the first image matrix to obtain a dark field matrix, and then set the data in the dark field matrix whose value is less than the value threshold to 0, and set the value to be greater than or The data equal to the numerical threshold is set to 1, and then the normalized dark field matrix is obtained. Finally, the image matrix of the image received by the projector and the normalized dark field matrix are ANDed to realize the The image received by the projector undergoes dark field processing.