Method and apparatus for calibrating a projector

Abstract

Embodiments of the present application relate to a projection picture correction method and device, the method comprising: obtaining a first image and a second image of the projection picture collected by a camera, wherein the first image comprises an image of a reference object on a projection surface at a first time, the second image comprises an image of the reference object on the projection surface at a second time, and the reference object is a shape pattern facilitating identification of spatial changes; determining a first pose of the reference object in the first image and a second pose of the reference object in the second image; and correcting the projection picture based on a change feature between the first pose and the second pose. Thus, the projection picture can be corrected by the change feature of the image poses of the reference object at different times. In this way, in a scenario in which a correction object is required to participate in projection picture correction, the correction complexity of the correction object can be reduced.

Description

Technical Field

[0001] This application relates to the field of projector technology, and more particularly to a projector calibration method and apparatus. Background Technology

[0002] Currently, most projectors on the market use sensors to measure the angle of the projector relative to the projection plane for automatic correction. However, due to limitations in usage scenarios and accuracy, even with factory calibration, the automatic correction effect can still be unsatisfactory, causing inconvenience for users. Furthermore, collisions or drops during transport or user use can further worsen the automatic correction performance.

[0003] Therefore, most projectors offer a user-involved calibration solution, such as manual calibration. However, current manual calibration methods often rely on a specific page covering the entire screen. Users need to navigate to a specific menu and repeatedly switch coordinate points, adjusting directional keys at each point. Furthermore, adjusting one coordinate point may cause another to shift, requiring repeated adjustments at multiple points until the entire image reaches a satisfactory rectangle. This process is time-consuming, cumbersome, and provides a poor user experience. Summary of the Invention

[0004] In view of this, in order to solve the technical problem of how to reduce the calibration complexity of the calibration object in scenarios where the calibration object needs to participate in the calibration of the projected image, the embodiments of this application provide a calibration method and apparatus for a projector.

[0005] In a first aspect, embodiments of this application provide a method for calibrating a projector, the method comprising:

[0006] Acquire a first image and a second image of the projected image captured by the camera, wherein the first image includes the image of the reference object on the projection surface at a first moment, and the second image includes the image of the reference object on the projection surface at a second moment, and the reference object is a shape or pattern that facilitates the identification of spatial changes.

[0007] Determine the first pose of the reference object in the first image and the second pose of the reference object in the second image;

[0008] Based on the change characteristics between the first pose and the second pose, the projected image is corrected.

[0009] In one possible implementation, the aforementioned change features represent movement information of the second pose relative to the aforementioned first pose; and

[0010] The above-mentioned correction of the projected image based on the change characteristics between the first pose and the second pose includes:

[0011] Determine the movement information of the second position relative to the first position, wherein the second position is the position represented by the second pose, and the first position is the position represented by the first pose;

[0012] Based on the aforementioned motion information, the projected image is corrected.

[0013] In one possible implementation, the aforementioned variation features represent rotation information of the second pose relative to the first pose.

[0014] The above-mentioned correction of the projected image based on the change characteristics between the first pose and the second pose includes:

[0015] Determine the rotation information of the second pose relative to the first pose, wherein the second pose is the pose represented by the second pose and the first pose is the pose represented by the first pose.

[0016] Based on the rotation information mentioned above, the projected image is corrected.

[0017] In one possible implementation, the projected image includes a preset number of image areas; and

[0018] The aforementioned camera captures the first image and the second image using the following method:

[0019] During the movement of the image of the aforementioned reference object, at preset time intervals, the first image and the second image of the projected screen are acquired respectively. The image movement process is the movement of the image of the aforementioned reference object within the target screen area.

[0020] In one possible implementation, the above-mentioned correction of the projected image based on the change characteristics between the first pose and the second pose includes:

[0021] Determine the target correction strategy corresponding to the aforementioned target image area;

[0022] The projected image is corrected based on the change characteristics between the first pose and the second pose, and the target correction strategy, which includes rotating the projected image and / or moving the projected image.

[0023] In one possible implementation, the target correction strategy for determining the target image region includes:

[0024] When the region type of the target image area is the first type, the target correction strategy corresponding to the target image area is determined as the first correction strategy, wherein the first correction strategy means rotating the entire projected image.

[0025] When the region type of the target image area is the second type, the target correction strategy corresponding to the target image area is determined to be the second correction strategy, wherein the second correction strategy means moving the corner point of the projected image.

[0026] When the region type of the target image area is the third type, the target correction strategy corresponding to the target image area is determined to be the third correction strategy, wherein the third correction strategy means moving the entire projected image.

[0027] In one possible implementation, the camera acquires the first image and the second image in the following manner:

[0028] In response to the projector receiving a trigger signal for a calibration operation, the camera is controlled to capture an image of the projected screen of the projector at preset time intervals, and the two images captured by the camera consecutively are used as the first image and the second image, respectively.

[0029] The preset duration is determined based on the frame rate of the camera.

[0030] In one possible implementation, the color of the image of the reference object on the projection surface is a first color; and

[0031] Before acquiring the first and second images of the projected image captured by the camera, the method further includes:

[0032] Receive the trigger signal for the correction operation of the above-mentioned projected image;

[0033] In response to the aforementioned trigger signal, a light signal of the second color is projected onto the projection screen of the projector.

[0034] Wherein, the contrast between the second color and the first color is greater than a preset contrast threshold.

[0035] In one possible implementation, the reference object is the projection of a laser beam emitted by the laser device onto the projection surface of the projector, and / or the shape of the image of the reference object is cross-shaped.

[0036] Secondly, embodiments of this application provide a calibration device for a projector, the device comprising:

[0037] The acquisition unit is used to acquire a first image and a second image of the projected image captured by the camera, wherein the first image includes the image of the reference object on the projection surface at a first moment, and the second image includes the image of the reference object on the projection surface at a second moment, and the reference object is a shape or pattern that facilitates the identification of spatial changes.

[0038] The determining unit is used to determine the first pose of the reference object in the first image and the second pose of the reference object in the second image.

[0039] The correction unit is used to correct the projected image based on the change characteristics between the first pose and the second pose.

[0040] In one possible implementation, the aforementioned change features represent movement information of the second pose relative to the aforementioned first pose; and

[0041] The above-mentioned correction of the projected image based on the change characteristics between the first pose and the second pose includes:

[0042] Determine the movement information of the second position relative to the first position, wherein the second position is the position represented by the second pose, and the first position is the position represented by the first pose;

[0043] Based on the aforementioned motion information, the projected image is corrected.

[0044] In one possible implementation, the aforementioned variation features represent rotation information of the second pose relative to the first pose.

[0045] The above-mentioned correction of the projected image based on the change characteristics between the first pose and the second pose includes:

[0046] Determine the rotation information of the second pose relative to the first pose, wherein the second pose is the pose represented by the second pose and the first pose is the pose represented by the first pose.

[0047] Based on the rotation information mentioned above, the projected image is corrected.

[0048] In one possible implementation, the projected image includes a preset number of image areas; and

[0049] The aforementioned camera captures the first image and the second image using the following method:

[0050] During the movement of the image of the aforementioned reference object, at preset time intervals, the first image and the second image of the projected screen are acquired respectively. The image movement process is the movement of the image of the aforementioned reference object within the target screen area.

[0051] In one possible implementation, the above-mentioned correction of the projected image based on the change characteristics between the first pose and the second pose includes:

[0052] Determine the target correction strategy corresponding to the aforementioned target image area;

[0053] The projected image is corrected based on the change characteristics between the first pose and the second pose, and the target correction strategy, which includes rotating the projected image and / or moving the projected image.

[0054] In one possible implementation, the target correction strategy for determining the target image region includes:

[0055] When the region type of the target image area is the first type, the target correction strategy corresponding to the target image area is determined as the first correction strategy, wherein the first correction strategy means rotating the entire projected image.

[0056] When the region type of the target image area is the second type, the target correction strategy corresponding to the target image area is determined to be the second correction strategy, wherein the second correction strategy means moving the corner point of the projected image.

[0057] When the region type of the target image area is the third type, the target correction strategy corresponding to the target image area is determined to be the third correction strategy, wherein the third correction strategy means moving the entire projected image.

[0058] In one possible implementation, the camera acquires the first image and the second image in the following manner:

[0059] In response to the projector receiving a trigger signal for a calibration operation, the camera is controlled to capture an image of the projected screen of the projector at preset time intervals, and the two images captured by the camera consecutively are used as the first image and the second image, respectively.

[0060] The preset duration is determined based on the frame rate of the camera.

[0061] In one possible implementation, the color of the image of the reference object on the projection surface is a first color; and

[0062] Before acquiring the first and second images of the projected image captured by the camera, the device further includes:

[0063] The receiving unit is used to receive the trigger signal for the correction operation of the above-mentioned projected image;

[0064] The projection unit is used to project a second color light signal onto the projection screen of the projector in response to the trigger signal mentioned above.

[0065] Wherein, the contrast between the second color and the first color is greater than a preset contrast threshold.

[0066] In one possible implementation, the reference object is the projection of a laser beam emitted by the laser device onto the projection surface of the projector, and / or the shape of the image of the reference object is cross-shaped.

[0067] Thirdly, embodiments of this application provide an electronic device, including:

[0068] Memory, used to store computer programs;

[0069] A processor is configured to execute a computer program stored in the aforementioned memory, and when the aforementioned computer program is executed, to implement the method of any embodiment of the projector calibration method of the first aspect of this application.

[0070] Fourthly, embodiments of this application provide a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, it implements the method of any embodiment of the projector calibration method of the first aspect described above.

[0071] Fifthly, embodiments of this application provide a computer program product including computer-readable code that, when executed on a device, causes a processor in the device to implement the method of any embodiment of the projector calibration method of the first aspect described above.

[0072] The projector calibration method provided in this application can acquire a first image and a second image of the projected image captured by a camera. The first image includes an image of a reference object on the projection surface at a first moment, and the second image includes an image of the reference object on the projection surface at a second moment. The reference object is a shape or pattern that facilitates the identification of spatial changes. Then, a first pose of the reference object in the first image and a second pose of the reference object in the second image are determined. Finally, the projected image is calibrated based on the change characteristics between the first and second poses. Thus, projected image calibration can be achieved by utilizing the change characteristics of the image pose of the reference object at different times. This reduces the calibration complexity of the calibration object in scenarios where calibration is required. Attached Figure Description

[0073] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0074] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0075] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0076] Figure 1 A schematic flowchart illustrating a projector calibration method provided in an embodiment of this application;

[0077] Figure 2 A schematic flowchart illustrating another projector calibration method provided in this application embodiment;

[0078] Figure 3A Figure K is a schematic diagram of an application scenario of a projector calibration method provided in an embodiment of this application;

[0079] Figure 3L A schematic flowchart illustrating another projector calibration method provided in this application embodiment;

[0080] Figure 4 A schematic diagram of the structure of a projector calibration device provided in an embodiment of this application;

[0081] Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0082] Various exemplary embodiments of this application will now be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of this application.

[0083] Those skilled in the art will understand that the terms "first" and "second" in the embodiments of this application are only used to distinguish different steps, devices or modules, and do not represent any specific technical meaning, nor do they indicate the logical order between them.

[0084] It should also be understood that in this embodiment, "multiple" can refer to two or more, and "at least one" can refer to one, two or more.

[0085] It should also be understood that any component, data or structure mentioned in the embodiments of this application can generally be understood as one or more unless explicitly defined or given contrary guidance in the context.

[0086] Furthermore, the term "and / or" in this application is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this application generally indicates that the preceding and following related objects have an "or" relationship.

[0087] It should also be understood that the description of the various embodiments in this application emphasizes the differences between the various embodiments, and the similarities or similarities can be referred to each other. For the sake of brevity, they will not be described in detail.

[0088] The following description of at least one exemplary embodiment is merely illustrative and is not intended to limit the scope of this application or its application or use.

[0089] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0090] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0091] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. To facilitate understanding of the embodiments of this application, the application will be described in detail below with reference to the accompanying drawings and embodiments. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0092] To address the technical problem of reducing the calibration complexity of a calibration object in scenarios where the object needs to be calibrated in the projection image calibration, this application provides a calibration method and apparatus for a projector, which can reduce the calibration complexity of the object in scenarios where the object needs to be calibrated in the projection image calibration.

[0093] Figure 1 This is a flowchart illustrating a projector calibration method provided in an embodiment of this application. This method can be applied to one or more electronic devices such as projectors, smartphones, laptops, desktop computers, portable computers, and servers. Furthermore, the execution entity of this method can be hardware or software. When the execution entity is hardware, it can be one or more electronic devices. For example, a single electronic device can execute this method, or multiple electronic devices can cooperate with each other to execute this method. When the execution entity is software, this method can be implemented as multiple software programs or software modules, or as a single software program or software module. No specific limitations are made here.

[0094] like Figure 1 As shown, the method specifically includes:

[0095] Step 101: Acquire a first image and a second image of the projected image captured by the camera. The first image includes the image of the reference object on the projection surface at a first moment, and the second image includes the image of the reference object on the projection surface at a second moment. The reference object is a shape or pattern that facilitates the identification of spatial changes.

[0096] In this embodiment, the projected image can be the image formed on the projection surface after the projector projects an image or video. The projection surface can be used to display the projected image formed by the projector. For example, the projection surface can be a plane or curved surface where the projector projects the image or video.

[0097] The first moment and the second moment can be two different moments. The duration between the first moment and the second moment can be a preset fixed duration or a variable duration.

[0098] The reference object can be the projection of the laser beam emitted by the laser device onto the projection surface of the projector. The shape of the image of the reference object can be a dot, a line, or other shapes.

[0099] Step 102: Determine the first pose of the reference object in the first image and the second pose of the reference object in the second image.

[0100] In this embodiment, the first pose may include the position and / or orientation of the first image (i.e., the image of the reference object on the projection surface at the first moment). The position of the first image may represent the position of the first image in the projected image. The orientation of the first image may represent the angle, direction, etc., of the first image's rotation relative to the first preset image of the reference object.

[0101] The second pose may include the position and / or orientation of the second image (i.e., the image of the reference object on the projection surface at the second moment). The position of the second image may represent the position of the second image in the projected image. The orientation of the second image may represent the angle, direction, etc., of the second image's rotation relative to a second preset image of the reference object.

[0102] The first preset image and the second preset image can be the same or different.

[0103] Step 103: Correct the projected image based on the change characteristics between the first pose and the second pose.

[0104] In this embodiment, after obtaining the first pose and the second pose, the change characteristics between the first pose and the second pose can be determined. The projected image can then be corrected accordingly.

[0105] In some optional implementations of this embodiment, the change feature represents the movement information of the second pose relative to the first pose.

[0106] Based on this, the projected image can be corrected using the following method, based on the change characteristics between the first and second poses:

[0107] The first step is to determine the movement information of the second position relative to the first position.

[0108] Wherein, the second position is the position represented by the second pose, and the first position is the position represented by the first pose.

[0109] The movement information can be information that moves from a first position to a second position, or information that moves from a second position to a first position.

[0110] In some cases, when the acquisition time of the first image is before the acquisition time of the second image, the motion information can be related information about moving from the first position to the second position; when the acquisition time of the first image is after the acquisition time of the second image, the motion information can be related information about moving from the second position to the first position.

[0111] The second step is to correct the projected image based on the motion information.

[0112] Here, the projected image can be corrected based on motion information by pre-setting a correspondence.

[0113] The preset correspondence represents the correspondence between motion information and the projector's correction method.

[0114] It is understandable that, in the optional implementation, the projected image can be corrected by the movement information of the second position relative to the first position. In this way, the object to be corrected only needs to move the projection of the reference object in the projected image to achieve the correction of the projected image, thereby further reducing the correction complexity of the object to be corrected.

[0115] In some optional implementations of this embodiment, the change feature represents the rotation information of the second pose relative to the first pose.

[0116] Based on this, the projected image can be corrected using the following method, based on the change characteristics between the first and second poses:

[0117] The first step is to determine the rotation information of the second pose relative to the first pose.

[0118] The second pose is the pose represented by the second position, and the first pose is the pose represented by the first position.

[0119] Rotation information can be information about rotating from a first attitude to a second attitude, or information about rotating from a second attitude to a first attitude.

[0120] In some cases, when the acquisition time of the first image is before the acquisition time of the second image, the motion information can be related to the attitude from the first attitude to the second attitude; when the acquisition time of the first image is after the acquisition time of the second image, the motion information can be related to the rotation from the second attitude to the first attitude.

[0121] The second step is to correct the projected image based on the rotation information.

[0122] Here, the projected image can be corrected based on rotation information by pre-setting a correspondence.

[0123] The preset correspondence represents the correspondence between rotation information and the projector's correction method.

[0124] It is understandable that, in the optional implementation, the projected image can be corrected by using the rotation information of the second posture relative to the first posture. In this way, the object to be corrected only needs to rotate the projection of the reference object in the projected image to achieve the projected image correction, thereby further reducing the correction complexity of the object to be corrected.

[0125] In some optional implementations of this embodiment, the projected image includes a preset number of image areas.

[0126] Here, the projected image can be divided into a preset number of regions, thus obtaining a preset number of image regions.

[0127] The shape and size of each of the preset number of screen areas can be the same or different. For example, the preset number of screen areas can be... Figure 3B The image shows six areas. These include five circular areas and one irregular area in the projected image, excluding the five circular areas.

[0128] Based on this, the camera can acquire the first image and the second image in the following way: during the movement of the image of the reference object, the first image and the second image of the projected screen are acquired at preset time intervals, wherein the image movement process is: the movement process of the image of the reference object in the target screen area.

[0129] The target screen area is defined as any screen area selected and adjusted from among a preset number of screen areas, which is a reference object.

[0130] The preset duration can be, for example, 16 milliseconds, 20 milliseconds, etc.

[0131] In addition, the number of cameras can be one or two.

[0132] It is understandable that, in the optional implementation, the first and second images can be acquired while the image of the reference object moves within the target image area. Therefore, the target image area can be corrected using the first and second poses, thus improving the precision of the projected image correction compared to overall image correction.

[0133] In some application scenarios among the optional implementation methods, the projected image can be corrected based on the change characteristics between the first pose and the second pose, as follows:

[0134] The first step is to determine the target correction strategy corresponding to the target image area.

[0135] Among them, the target correction strategy can be the correction strategy corresponding to the target image area.

[0136] Here, different image areas (including the target image area) may, but do not necessarily, correspond to different correction strategies.

[0137] For example, correction strategies can represent moving the entire projected image, rotating the entire projected image, or moving the corner points of the projected image.

[0138] The second step is to correct the projected image based on the change characteristics between the first and second poses and the target correction strategy, which includes rotating and / or moving the projected image.

[0139] Here, after determining the target correction strategy, the projected image can be corrected according to the change characteristics between the first pose and the second pose.

[0140] It is understandable that in the above application scenarios, the projected image can be calibrated according to the target image area corresponding to the target image area. Therefore, by associating different calibration strategies with different image areas, the calibration complexity of the target image can be further reduced.

[0141] In some of the above application scenarios, the following methods can be used to determine the target correction strategy corresponding to the target image area:

[0142] If the region type of the target image area is Type 1, then the target correction strategy corresponding to the target image area is determined as the first correction strategy.

[0143] The first correction strategy involves rotating the entire projected image.

[0144] When the region type of the target image area is the second type, the target correction strategy corresponding to the target image area is determined to be the second correction strategy.

[0145] The second correction strategy involves moving the corner points of the projected image.

[0146] When the target image area is of type 3, the target correction strategy corresponding to the target image area is determined to be the third correction strategy.

[0147] The third correction strategy involves moving the entire projected image.

[0148] Here, the second, third, and fourth types can be three different region types. For example, as shown... Figure 3BAs shown, with a preset quantity of 6, the region type of the central circular screen area can be determined as the first type, the region type of the circular screen areas located at the four corners can be determined as the second type, and the region type of another irregular screen area can be determined as the third type.

[0149] The correspondence between screen areas and correction strategies can be set by the user or by the developers.

[0150] It is understandable that in the above situations, at least three types of correction strategies can be set to achieve overall rotation and movement of the projected image, as well as movement of the corner points of the projected image. This can improve the accuracy of the projected image correction and enrich the correction methods of the projector.

[0151] In some optional implementations of this embodiment, the camera acquires the first image and the second image in the following manner:

[0152] In response to the projector receiving a trigger signal for a calibration operation, the camera is controlled to capture an image of the projected image of the projector at preset time intervals, and the two images captured by the camera in succession are used as the first image and the second image, respectively.

[0153] The preset duration is determined based on the camera's frame rate.

[0154] Trigger signals can be used to trigger calibration operations. For example, a trigger signal can be generated when the calibration target outputs a preset voice message, or when a preset button on the remote control is pressed, and the projector can then receive this trigger signal.

[0155] Furthermore, the preset duration can be negatively correlated with the camera's frame rate. For example, if the camera's frame rate is 30 FPS (Frames Per Second), the preset duration could be 33 milliseconds; if the camera's frame rate is 60 FPS, the preset duration could be 16 milliseconds.

[0156] It is understandable that, in the optional implementation, when the projector receives the trigger signal for the correction operation, it can control the camera to capture an image of the projected image at preset intervals. This allows for multiple corrections of the projected image based on the first and second images during the correction operation. Therefore, the timeliness of the correction effect presentation can be improved.

[0157] In some optional implementations of this embodiment, the reference object is the projection of a laser beam emitted by a laser device onto the projection surface of a projector.

[0158] The laser unit can be installed in the projector's remote control or outside of it.

[0159] It is understandable that, among the optional implementation methods, the projection image can be corrected by using the laser beam emitted by the laser device, which can further reduce the complexity of projection image correction.

[0160] In some optional implementations of this embodiment, the shape of the image of the reference object is cross-shaped.

[0161] It is understandable that, in the optional implementation, since the shape of the reference object's image is cross-shaped, the movement and rotation of the reference object can be identified more accurately through the first and second images compared to point-like or line-like images, thereby improving the accuracy of the projected image correction.

[0162] It should be noted that, where there is no conflict, the technical features described in different alternative implementations can be included in the same embodiment. For the sake of brevity, they will not be elaborated here.

[0163] The projector calibration method provided in this application can acquire a first image and a second image of the projected image captured by a camera. The first image includes the image of a reference object on the projection surface at a first moment, and the second image includes the image of the reference object on the projection surface at a second moment. The reference object is a shape or pattern that facilitates the identification of spatial changes. Then, the first pose of the reference object in the first image and the second pose of the reference object in the second image are determined. Finally, the projected image is calibrated based on the change characteristics between the first and second poses. Thus, projected image calibration can be achieved by utilizing the change characteristics of the image pose of the reference object at different times. This reduces the calibration complexity of the calibration object in scenarios where calibration is required.

[0164] Figure 2 This is a schematic flowchart illustrating another projector calibration method provided in an embodiment of this application. Figure 2 As shown, the method specifically includes:

[0165] Step 201: Receive a trigger signal for a correction operation on the projected image.

[0166] In this embodiment, the trigger signal can be used to trigger the calibration operation. As an example, a trigger signal can be generated when the calibration object outputs a preset voice or when a preset button in the remote control is pressed, and the execution subject can then receive the trigger signal.

[0167] Step 202: In response to the trigger signal, project a light signal of the second color onto the projection screen of the projector.

[0168] In this embodiment, after receiving the trigger signal, the executing entity can project a light signal of the second color onto the projection screen of the projector so that the projection screen displays an image of the second color.

[0169] Step 203: Obtain the first image and the second image of the projected image captured by the camera. The first image includes the image of the reference object on the projection surface at a first moment, and the second image includes the image of the reference object on the projection surface at a second moment. The reference object is a shape or pattern that facilitates the identification of spatial changes, and the color of the image of the reference object on the projection surface is the first color.

[0170] In this embodiment, the color of the image of the reference object on the projection surface is the first color.

[0171] The contrast between the second color and the first color is greater than the preset contrast threshold.

[0172] As an example, the first color can be black and the second color can be white; or the first color can be white and the second color can be black. Alternatively, the first color can be green and the second color can be red; or the first color can be red and the second color can be green.

[0173] As another example, the first color and the second color can be complementary colors, that is, colors opposite each other on the color wheel.

[0174] As another example, the first color and the second color can be warm or cool colors.

[0175] Furthermore, the implementation method of step 203 can be found in [reference needed]. Figure 1 Step 101 in the corresponding embodiment will not be repeated here.

[0176] Step 204: Determine the first pose of the reference object in the first image and the second pose of the reference object in the second image.

[0177] In this embodiment, step 204 and Figure 1 Step 102 in the corresponding embodiment is basically the same, and will not be repeated here.

[0178] Step 205: Correct the projected image based on the change characteristics between the first pose and the second pose.

[0179] In this embodiment, step 205 and Figure 1 Step 103 in the corresponding embodiment is basically the same, and will not be repeated here.

[0180] It should be noted that, in addition to the contents described above, this embodiment may also include... Figure 1 The corresponding technical features described in the corresponding embodiments, thereby achieving Figure 1For details on the technical effectiveness of the projector calibration method shown, please refer to [link / reference needed]. Figure 1 The relevant descriptions are presented concisely and will not be elaborated upon here.

[0181] In the projector calibration method provided in this application embodiment, the first image and the second image may respectively contain a first color and a second color with high contrast. In this way, the pose change of the reference object can be identified through the first image and the second image, and then the projection screen can be calibrated in a corresponding manner, thereby further improving the accuracy of the projection screen calibration.

[0182] The following describes the embodiments of this application by way of example. However, it should be noted that the following content is only used to understand the technical solutions of the embodiments of this application and does not constitute a limitation on the protection scope of the embodiments of this application.

[0183] Before introducing this plan, the following explanations are provided for the technical terms used in it:

[0184] Laser beam: Used to project horizontal or vertical lines. Green laser beams are especially easier to see in daylight and bright environments, so this solution can use green lasers to improve visibility and accuracy.

[0185] Camera: refers to a camera, which is a device that uses optical lenses to focus light onto a photosensitive element to record images.

[0186] DMD (Digital Micromirror Device): An optical semiconductor device and a core component of DLP (Digital Light Processing) technology.

[0187] Main services: The core software processes that automatically start in the background after power-on as described in this solution include service threads such as high-brightness color projection screen edge, pattern image display, T-calibration (i.e., keystone correction), button monitoring, camera recognition, and image algorithm analysis.

[0188] In related technologies, projectors can automatically perform keystone correction by calculating the angle of the projector relative to the projection surface based on camera recognition, G-sensor (Gravity-sensor), or ToF (Time-of-Flight) sensors. However, due to limitations in usage scenarios and accuracy, even if the relative position is calibrated at the factory, the automatic correction still results in poor performance, causing inconvenience to users. Furthermore, the automatic correction effect will be further worse due to collisions or drops during machine transportation or user use. Therefore, projectors can provide a manual correction solution. However, the currently provided manual compensation solutions are based on specific pages covering the entire screen. Users need to enter a specific menu first, and during the adjustment process, users need to switch coordinate points at least four times, adjusting the directional keys multiple times to move the coordinate point. When adjusting one coordinate point, it may cause another coordinate point to shift, requiring adjustments to four coordinate points until the entire image approaches a rectangle that satisfies the user. The whole process is time-consuming, cumbersome, and has a poor user experience.

[0189] This solution describes a method that uses a remote control paired with the projector, featuring a built-in laser beam and a specific button (named the T-calibration button). After the projector is powered on, the user activates the T-calibration button, and the remote control emits a green laser beam. Simultaneously, the main service receives this button press and initiates a camera recognition service to identify whether the laser beam is on the screen and its relative displacement, thus adjusting the T-calibration in real time. This solution is applicable to projectors with camera recognition, whose remote controls have a dedicated button for emitting a green laser beam, and where users want to manually adjust the T-calibration or perform manual compensation after automatic adjustment.

[0190] Specifically, refer to Figure 3L The steps of this solution are as follows:

[0191] 1. After the projector is powered on, the "main service" will automatically start and run in the background, listening for input of the T-key key.

[0192] 2. When the user presses the T-correction button on the remote control, the remote control sends the button value to the projector and simultaneously activates the laser beam on the remote control.

[0193] Here, the emitted laser beam is in a cross pattern, which is more conducive to the camera recognizing up, down, left, right movement and determining the direction of rotation. The laser beam itself (commonly green or red laser beams) can be a dot pattern, but it is not conducive to rotation detection; it can be a line, but it is not conducive to detecting movement in the parallel direction.

[0194] 3. After receiving the T-key button event, the main service starts the camera to continuously capture images, and at the same time, the main service fills the edges of the projected image with a highlight color.

[0195] Here, the 33ms interval is determined based on the selected camera specifications. Projectors commonly use a 30FPS camera frame rate, requiring 33ms to capture a single image. This can be adjusted according to specifications; for example, a 60FPS frame rate can capture an image in 16ms.

[0196] Here, this solution uses pure red (i.e., the first color) to fill the four sides of the projection area, which means that the border of the projected image becomes a bright red frame. The bright red contrasts strongly with the bright green (i.e., the second color) laser beam, making it easier for the camera to recognize and process the image.

[0197] 3.1 Determine whether the cross falls within the projection area:

[0198] Similar graphic contour detection is performed by taking pictures with a camera to detect and identify the coordinates of four points of the projected image on the camera image. Edge information detection is used to find the coordinates of the cross on the camera image (i.e., the first and second positions). Simultaneously, the Hough Circle Transform is used to detect rings (i.e., image regions) in the image and find the center coordinates and radius of each ring, facilitating subsequent calculations of which ring the cross falls within.

[0199] In practice, users may not be pointing the remote control at the projected image. In this case, the laser beam may not be within the projected image. However, the camera's FOV (Field of View) is larger than the projected image, so the image captured by the camera includes the projected image. Regardless of whether the laser beam is within the projected image, it can be recognized. The main service analyzes the continuous image captures by the camera and, based on the analysis results, pops up relevant interactive prompts to guide the user to move the laser beam.

[0200] The general formula for the Hough circle transformation is: (xa) 2 +(yb) 2 =r 2 , where (a,b) are the coordinates of the center of the circle and r is the radius of the circle.

[0201] 3.2 If the laser beam is not within the projected image, a pop-up window will prompt the user to "move the laser beam into the image" (e.g., ...). Figure 3A If the laser beam is within the projected image, a semi-transparent ring will be displayed at the center and four vertices of the image, with a cross pattern inside the ring (e.g., ...). Figure 3B ).

[0202] 4. Perform screen adjustment operations:

[0203] 4.1 When the user presses the Enter key, a trigger signal is generated, which starts the screen adjustment service in the main service.

[0204] 4.2 Analyze which ring the current laser beam cross is located inside or outside, and adjust the image accordingly based on the area.

[0205] 4.3 Identify the direction of movement, distance of movement, direction of rotation, and angle of rotation of the cross.

[0206] Here, a camera can be used to capture images of the cross before and after its movement. First, the corner information and features of the cross are detected by corner point detection, and feature matching is performed. The transformation matrix of the cross from the first image (i.e., the first image) to the second image (i.e., the second image) is calculated. Movement and rotation information are extracted from the transformation matrix, and the movement direction, movement distance, rotation direction, and rotation angle are finally output.

[0207] 4.4 Move and rotate the crosshair in tandem to adjust the visuals:

[0208] When the laser beam is within the screen but not within the circular pattern, the user is prompted to direct the laser beam within the circular pattern on the screen (e.g., ...). Figure 3C When the laser beam is located at the center of a certain ring, the corresponding ring and cross are highlighted, and a text prompts the user to press the Enter key to perform the corresponding operation. For example, when it is located in the center ring, the user is prompted that they can perform horizontal, vertical, and overall screen rotation (e.g., ...). Figure 3D If it is located in one of the other four points of the ring, then the corresponding point is adjusted vertically or horizontally. For example, when it is at the top left vertex, ... Figure 3E As shown, the other three vertices are operated on in a similar manner.

[0209] 4.4.1 When the laser beam is located in the central ring, the camera takes real-time pictures, identifies the offset or rotation direction of the laser beam relative to the ring, and performs horizontal, vertical, or rotation operations on the image, such as... Figure 3F As shown.

[0210] a. When the user lifts the remote control upwards, the laser beam moves upwards, and the image relative to the screen... Figure 3D The effect of the change is as follows Figure 3F As shown.

[0211] b. When the user moves the remote control downwards, the laser beam moves downwards, and the image relative to the screen... Figure 3D The effect of the change is as follows Figure 3G As shown.

[0212] c. Moving left and right has a similar effect to moving up and down, but the change is in the vertical direction.

[0213] d. When the user rotates the projector, the laser beam also rotates relative to the crosshair on the screen, and the screen rotates relative to... Figure 3D The effect of the change is as follows Figure 3H As shown.

[0214] 4.4.2 When the laser beam forms a ring around any vertex, the camera takes a real-time picture, identifies the laser beam's offset direction relative to the ring (up, down, left, right), and adjusts the coordinates of the corresponding vertex. For example, if the laser beam is located at the top left vertex, when the user moves the laser beam to the left, the position relative to the ring will be adjusted. Figure 3E Changes such as Figure 3I As shown. (Similarly, adjust the other vertical directions, as well as the other three vertices).

[0215] 4.4.3 When the laser beam is not located in any circular ring, pressing and holding the Enter key will move the entire screen up, down, left, and right. Figure 3B The effect of the change is as follows Figure 3J As shown.

[0216] 5. After any of the above adjustments are completed, the user releases the Enter key. At this time, moving the laser beam will not make any adjustments to the screen. The user can adjust the position of the laser beam projected on the screen to switch the area to be adjusted. For example, after adjusting the top left corner, the user releases the Enter key, moves the laser beam to the bottom left corner, and then presses the Enter key again to switch to adjusting the bottom left corner position.

[0217] 6. Once the adjustment is complete, the user releases the Enter key to exit the adjustment, then presses the T-calibration button again to turn off the laser beam. The projector will receive this button press, exit the camera recognition service, and a pop-up message will indicate "Adjustment complete." All adjustment-related patterns will then be closed. Figure 3K As shown.

[0218] It should be noted that, in addition to the contents described above, this embodiment may also include the technical features described in the above embodiments, thereby achieving the technical effect of the projector correction method shown above. Please refer to the above description for details. For the sake of brevity, it will not be elaborated here.

[0219] The projector calibration method provided in this application reduces the complexity of manually adjusting T-calibration and improves user operability. It also reduces screen obstruction during viewing, integrating T-calibration, screen rotation, and screen movement into a single operation. Furthermore, T-calibration, screen movement, and screen rotation are performed by recognizing the movement of an external movable reference frame (such as a laser beam) relative to the screen using the camera.

[0220] Figure 4 This is a schematic diagram of the structure of a projector calibration device provided in an embodiment of this application. Specifically, it includes:

[0221] The acquisition unit 401 is used to acquire a first image and a second image of the projected image captured by the camera. The first image includes the image of the reference object on the projection surface at a first moment, and the second image includes the image of the reference object on the projection surface at a second moment. The reference object is a shape or pattern that is easy to identify spatial changes.

[0222] The determining unit 402 is used to determine the first pose of the reference object in the first image and the second pose of the reference object in the second image;

[0223] The correction unit 403 is used to correct the projected image based on the change characteristics between the first pose and the second pose.

[0224] In one possible implementation, the change features represent movement information of the second pose relative to the first pose; and

[0225] Based on the change characteristics between the first pose and the second pose, the projected image is corrected, including:

[0226] Determine the movement information of the second position relative to the first position, wherein the second position is the position represented by the second pose, and the first position is the position represented by the first pose;

[0227] The projected image is corrected based on motion information.

[0228] In one possible implementation, the variation feature represents rotation information of the second pose relative to the first pose;

[0229] Based on the change characteristics between the first pose and the second pose, the projected image is corrected, including:

[0230] Determine the rotation information of the second pose relative to the first pose, where the second pose is the pose represented by the second pose and the first pose is the pose represented by the first pose.

[0231] The projected image is corrected based on rotation information.

[0232] In one possible implementation, the projected image includes a preset number of image areas; and

[0233] The camera captures the first and second images in the following manner:

[0234] During the movement of the reference object's image, at preset time intervals, the first and second images of the projected screen are captured respectively. The image movement process is the movement of the reference object's image within the target screen area.

[0235] In one possible implementation, the projected image is corrected based on the change characteristics between the first pose and the second pose, including:

[0236] Determine the target correction strategy corresponding to the target image area;

[0237] The projected image is corrected based on the change characteristics between the first pose and the second pose, as well as the target correction strategy, which includes rotating the projected image and / or moving the projected image.

[0238] In one possible implementation, determining a target correction strategy corresponding to the target image area includes:

[0239] When the region type of the target image area is the first type, the target correction strategy corresponding to the target image area is determined as the first correction strategy, wherein the first correction strategy means rotating the entire projected image.

[0240] When the region type of the target image area is the second type, the target correction strategy corresponding to the target image area is determined to be the second correction strategy, wherein the second correction strategy means moving the corner points of the projected image.

[0241] When the target image area is of type three, the target correction strategy corresponding to the target image area is determined to be the third correction strategy, where the third correction strategy means moving the entire projected image.

[0242] In one possible implementation, the camera acquires the first image and the second image in the following manner:

[0243] In response to the projector receiving a trigger signal for a calibration operation, the camera is controlled to capture an image of the projected image of the projector at preset time intervals, and the two images captured by the camera in succession are used as the first image and the second image, respectively.

[0244] The preset duration is determined based on the camera's frame rate.

[0245] In one possible implementation, the color of the image of the reference object on the projection surface is a first color; and

[0246] Before acquiring the first and second images of the projected image captured by the camera, the device also includes:

[0247] The receiving unit (not shown in the figure) is used to receive the trigger signal for the correction operation of the projected image;

[0248] The projection unit (not shown in the figure) is used to project a second color light signal onto the projection screen of the projector in response to a trigger signal.

[0249] Among them, the contrast between the second color and the first color is greater than the preset contrast threshold.

[0250] In one possible implementation, the reference object is: the projection of the laser beam emitted by the laser device onto the projection surface of the projector, and / or the shape of the image of the reference object is cross-shaped.

[0251] The projector calibration device provided in this embodiment can be as follows: Figure 4 The projector calibration device shown can perform all the steps of the above-mentioned projector calibration methods, thereby achieving the technical effects of the above-mentioned projector calibration methods. For details, please refer to the above descriptions. For the sake of brevity, further details are omitted here.

[0252] Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Figure 5 The illustrated electronic device 500 includes at least one processor 501, a memory 502, at least one network interface 504, and other user interfaces 503. The various components in the electronic device 500 are coupled together via a bus system 505. It is understood that the bus system 505 is used to implement communication between these components. In addition to a data bus, the bus system 505 also includes a power bus, a control bus, and a status signal bus. However, for clarity, ... Figure 5 The general designated all buses as Bus System 505.

[0253] The user interface 503 may include a display, keyboard, or clicking device (e.g., mouse, trackball, touchpad, or touchscreen).

[0254] It is understood that the memory 502 in the embodiments of this application can be volatile memory or non-volatile memory, or may include both volatile and non-volatile memory. The non-volatile memory can be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. The volatile memory can be random access memory (RAM), which is used as an external cache. By way of example, but not limitation, many forms of RAM are available, such as Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), Synchronous DRAM (SDRAM), Double Data Rate Synchronous DRAM (DDRSDRAM), Enhanced Synchronous DRAM (ESDRAM), Synchronous Link DRAM (SLDRAM), and Direct Rambus RAM (DRRAM). The memory 502 described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0255] In some implementations, memory 502 stores elements, executable units or data structures, or subsets thereof, or extended sets thereof: operating system 5021 and application program 5022.

[0256] The operating system 5021 includes various system programs, such as the framework layer, core library layer, and driver layer, used to implement various basic business functions and handle hardware-based tasks. The application program 5022 includes various applications, such as a media player and a browser, used to implement various application functions. Programs implementing the methods of this application embodiment can be included in application program 5022.

[0257] In this embodiment, by calling the program or instructions stored in memory 502, specifically the program or instructions stored in application program 5022, processor 501 executes the method steps provided in each method embodiment, including, for example:

[0258] Acquire a first image and a second image of the projected image captured by the camera, wherein the first image includes the image of the reference object on the projection surface at a first moment, and the second image includes the image of the reference object on the projection surface at a second moment, and the reference object is a shape or pattern that facilitates the identification of spatial changes.

[0259] Determine the first pose of the reference object in the first image and the second pose of the reference object in the second image;

[0260] The projected image is corrected based on the change characteristics between the first pose and the second pose.

[0261] The methods disclosed in the embodiments of this application can be applied to or implemented by processor 501. Processor 501 may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by the integrated logic circuit of the hardware in processor 501 or by instructions in the form of software. The processor 501 may be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this application can be directly embodied in the execution of a hardware decoding processor, or can be executed by a combination of hardware and software units in the decoding processor. The software units may be located in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. The storage medium is located in memory 502. Processor 501 reads the information in memory 502 and, in conjunction with its hardware, completes the steps of the above method.

[0262] It is understood that the embodiments described herein can be implemented in hardware, software, firmware, middleware, microcode, or a combination thereof. For hardware implementation, the processing unit can be implemented in one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), general-purpose processors, controllers, microcontrollers, microprocessors, other electronic units for performing the functions described above in this application, or combinations thereof.

[0263] For software implementation, the techniques described herein can be implemented by units that perform the functions described above. The software code can be stored in memory and executed by a processor. The memory can be implemented within the processor or external to the processor.

[0264] The electronic device provided in this embodiment may be as follows: Figure 5 The electronic device shown can perform all the steps of the above-mentioned projector calibration methods, thereby achieving the technical effects of the above-mentioned projector calibration methods. For details, please refer to the above descriptions. For the sake of brevity, further details are omitted here.

[0265] This application also provides a storage medium (computer-readable storage medium). This storage medium stores one or more programs. The storage medium may include volatile memory, such as random access memory; it may also include non-volatile memory, such as read-only memory, flash memory, hard disk, or solid-state drive; and it may also include combinations of the above types of memory.

[0266] When one or more programs in the storage medium can be executed by one or more processors to implement the above-described projector calibration method executed on the electronic device side.

[0267] The processor described above is used to execute the projector calibration program stored in the memory to implement the following steps of the projector calibration method executed on the electronic device side:

[0268] Acquire a first image and a second image of the projected image captured by the camera, wherein the first image includes the image of the reference object on the projection surface at a first moment, and the second image includes the image of the reference object on the projection surface at a second moment, and the reference object is a shape or pattern that facilitates the identification of spatial changes.

[0269] Determine the first pose of the reference object in the first image and the second pose of the reference object in the second image;

[0270] The projected image is corrected based on the change characteristics between the first pose and the second pose.

[0271] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0272] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented in hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0273] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “the above” as used herein may also mean including the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a specific order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0274] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for correcting a projected image, characterized in that, The method includes: Acquire a first image and a second image of the projected image captured by the camera, wherein the first image includes the image of the reference object on the projection surface at a first moment, and the second image includes the image of the reference object on the projection surface at a second moment, wherein the reference object is a shape or pattern that facilitates the identification of spatial changes. Determine the first pose of the reference object in the first image and the second pose of the reference object in the second image; The projected image is corrected based on the change characteristics between the first pose and the second pose.

2. The method according to claim 1, characterized in that, The change feature represents the movement information of the second pose relative to the first pose; as well as The step of correcting the projected image based on the change characteristics between the first pose and the second pose includes: Determine the movement information of the second position relative to the first position, wherein the second position is the position represented by the second pose, and the first position is the position represented by the first pose; The projected image is corrected based on the motion information.

3. The method according to claim 1, characterized in that, The change feature represents the rotation information of the second pose relative to the first pose; The step of correcting the projected image based on the change characteristics between the first pose and the second pose includes: Determine the rotation information of the second pose relative to the first pose, wherein the second pose is the pose represented by the second pose, and the first pose is the pose represented by the first pose; The projected image is corrected based on the rotation information.

4. The method according to claim 1, characterized in that, The projected image includes the target image area; and The camera acquires the first image and the second image in the following manner: During the movement of the image of the reference object, at preset time intervals, the first image and the second image of the projected screen are captured respectively, wherein the image movement process is: the movement process of the image of the reference object in the target screen area.

5. The method according to claim 4, characterized in that, The step of correcting the projected image based on the change characteristics between the first pose and the second pose includes: Determine the target correction strategy corresponding to the target image area; The projected image is corrected based on the change characteristics between the first pose and the second pose and the target correction strategy, which includes rotating the projected image and / or moving the projected image.

6. The method according to claim 5, characterized in that, The target correction strategy for determining the target image region includes: When the region type of the target image area is a first type, the target correction strategy corresponding to the target image area is determined to be the first correction strategy, wherein the first correction strategy means rotating the entire projected image; When the region type of the target image area is the second type, the target correction strategy corresponding to the target image area is determined to be the second correction strategy, wherein the second correction strategy indicates that the corner points of the projected image are moved; When the region type of the target image area is the third type, the target correction strategy corresponding to the target image area is determined to be the third correction strategy, wherein the third correction strategy means moving the entire projected image.

7. The method according to claim 2, characterized in that, The camera acquires the first image and the second image in the following manner: In response to the projector receiving a trigger signal for a calibration operation, the camera is controlled to capture an image of the projected screen at preset time intervals, and the two consecutive images captured by the camera are used as the first image and the second image, respectively. The preset duration is determined based on the frame rate of the camera.

8. The method according to claim 1, characterized in that, The color of the image of the reference object on the projection surface is the first color; as well as Before acquiring the first and second images of the projected image captured by the camera, the method further includes: Receive a trigger signal for a correction operation on the projected image; In response to the trigger signal, a light signal of the second color is projected onto the projection screen; Wherein, the contrast between the second color and the first color is greater than a preset contrast threshold.

9. The method according to any one of claims 1-8, characterized in that, The reference object is the projection of the laser beam emitted by the laser instrument onto the projection surface of the projector, and the shape of the image of the reference object is cross-shaped.

10. A calibration device for a projector, characterized in that, The device includes: The acquisition unit is used to acquire a first image and a second image of the projected image captured by the camera, wherein the first image includes the image of the reference object on the projection surface at a first moment, and the second image includes the image of the reference object on the projection surface at a second moment, and the reference object is a shape or pattern that facilitates the identification of spatial changes. The determining unit is used to determine the first pose of the reference object in the first image and the second pose of the reference object in the second image; The correction unit is used to correct the projected image based on the change characteristics between the first pose and the second pose.

Images