Image acquisition device, terminal and method for video conference, and storage medium

Abstract

Embodiments of the present application relate to the technical field of camera terminals. Disclosed are an image acquisition device, terminal and method for a video conference, and a storage medium. The device comprises: a wide-angle lens used for acquiring a first field of view area; and a plurality of telephoto lenses symmetrically arranged relative to the center of the wide-angle lens, wherein the optical axes of the plurality of telephoto lenses and the optical axis of the wide-angle lens intersect at a same virtual optical center, and the absolute value of the difference between a second field of view area obtained by combining field of view areas of the plurality of telephoto lenses and the first field of view area is smaller than a field of view area threshold. According to the image acquisition device in the embodiments of the present application, the wide-angle lens and the telephoto lenses are used in combination to increase the field of view coverage rate, and lossless picture zoom-in can be achieved by using the telephoto lenses and the wide-angle lens in combination; image distortion caused by different focusing information of different lenses is avoided by means of the settings of the virtual optical center and the field of view areas; and the telephoto lenses can be used in combination in most of the field of view area of the wide-angle lens for zoomed-in close-up.

Description

Image acquisition device, terminal, method and storage medium for video conferencing

[0001] Related applications

[0002] This application claims priority to Chinese patent application number 202311267503.0, filed on September 27, 2023, entitled “Image acquisition device, terminal, method and storage medium for video conferencing,” the entire text of which is incorporated herein by reference. Technical Field

[0003] The present application relates to the field of camera terminal technology, and in particular to an image acquisition device, terminal, method and storage medium for video conferencing. Background Art

[0004] Current video conferencing requires two key imaging qualities: panoramic coverage as much as possible while also providing clear close-ups of distant objects. Current video conferencing equipment struggles to achieve both panoramic coverage and image clarity. Wide-angle cameras offer a wider field of view, allowing for larger scenes, but the number of pixels per unit area is reduced, significantly reducing image clarity when zooming in on distant scenes. Telephoto lenses can produce sufficiently clear images, but their narrow field of view prevents them from covering most scenes.

[0005] In some related technologies, to improve the clarity of important areas in large scene images captured by wide-angle cameras, an increasing number of device manufacturers are equipping electronic devices with multiple lenses, stitching and synthesizing the images captured by these lenses using image matching algorithms. However, existing lenses produce image distortion, and the image quality captured by multiple lenses used to capture different scenes is low. This also makes the image stitching and synthesis algorithm difficult and requires high computing power from the image acquisition equipment.

[0006] Summary of the Invention

[0007] The present application provides an image acquisition device, terminal, method, and storage medium for video conferencing, which are used to address the defects of the above-mentioned related technologies in that both panoramic coverage and image clarity cannot be taken into account. The technical solution is as follows:

[0008] In a first aspect, an embodiment of the present application provides an image acquisition device for video conferencing, the device comprising:

[0009] a wide-angle lens, wherein the wide-angle lens is used to obtain a first field of view;

[0010] Multiple telephoto lenses are arranged symmetrically with respect to the center of the wide-angle lens, the optical axes of the multiple telephoto lenses intersect the optical axis of the wide-angle lens at a common virtual optical center, and the absolute value of the difference between a second field of view area obtained by combining the field of view areas of the multiple telephoto lenses and the first field of view area is less than a field of view area threshold.

[0011] In an optional solution of the first aspect, the angle between the optical axis of the telephoto lens and the optical axis of the wide-angle lens is not less than half the field of view angle of the telephoto lens.

[0012] In an optional solution of the first aspect, the telephoto lens at the same distance from the wide-angle lens has the same field of view angle.

[0013] In an optional solution of the first aspect, all telephoto lenses have the same field of view.

[0014] In an optional solution of the first aspect, the fields of view of every two telephoto lenses have an overlapping third field of view area, and the width of the projection of the third field of view area on the horizontal plane at a preset distance from the device is not less than a field of view width threshold.

[0015] In an optional scheme of the first aspect, the device also includes at least one annular rotating mechanism, the rotation axis of the annular rotating mechanism coincides with the optical axis of the wide-angle lens, the annular rotating mechanism includes a plurality of rotating bases, each rotating base is at the same distance from the axis of the wide-angle lens, a telephoto lens is provided on each rotating base, and the rotating mechanism drives the telephoto lens to rotate around the optical axis of the wide-angle lens through the rotating base.

[0016] In an optional solution of the first aspect, the device also includes a rotating base, on which the telephoto lens is detachably arranged, and the plane where the rotation axis of the rotating base is located is perpendicular to the plane where the optical axis of the wide-angle lens is located, and the rotating base is used to drive the telephoto lens to rotate around the rotation axis of the rotating base to adjust the angle between the optical axis of the telephoto lens and the optical axis of the wide-angle lens.

[0017] In a second aspect, an embodiment of the present application further provides a terminal, the terminal comprising:

[0018] A housing, the housing comprising a cavity, in which the image acquisition device provided by any one of the first aspects is installed;

[0019] The object side ends of the wide-angle lens and the telephoto lens are both located outside the housing.

[0020] In a third aspect, an embodiment of the present application further provides an image acquisition method, which is applied to the image acquisition device provided in any one of the first aspects above, and the method comprises the steps of:

[0021] Determine a target to be focused within the first field of view, and obtain a distance between the target to be focused and the device;

[0022] If the distance between the target to be focused and the device is less than a first distance threshold, the target to be focused is magnified by a wide-angle lens to generate a first focused image;

[0023] If the distance between the target to be focused and the device is greater than or equal to the first distance threshold and less than the second distance threshold, the target to be focused is first magnified using the wide-angle lens until the magnification of the wide-angle lens reaches the first magnification, and then the corresponding telephoto lens is switched to continue magnifying the target to be focused, thereby generating a second focused image;

[0024] If the distance between the target to be focused and the device is greater than or equal to the second distance threshold, the target to be focused is magnified by the wide-angle lens and the telephoto lens in sequence until the magnification of the telephoto lens reaches the second magnification. Digital amplification is performed on the basis of the focused image generated by the telephoto lens to generate a third focused image.

[0025] In a fourth aspect, the present application also provides a non-transitory computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, it implements the method provided by the first aspect of the embodiment of the present application or any one of the implementation methods of the first aspect.

[0026] The beneficial effects of the technical solutions provided by some embodiments of the present application include at least:

[0027] An embodiment of the present application provides an image acquisition device for video conferencing, which obtains a first field of view area through a wide-angle lens, thereby improving the viewing angle coverage in a video conferencing scenario; multiple telephoto lenses are arranged symmetrically relative to the center of the wide-angle lens, and the optical axes of the multiple telephoto lenses intersect with the optical axis of the wide-angle lens at the same virtual optical center, so that the multiple telephoto lenses and the wide-angle lens form an overlapping area, which is convenient for image synthesis, so that the telephoto lenses and the wide-angle lenses can be fused to losslessly magnify the picture, ensuring the quality of the collected image, and will not cause image distortion due to different focusing information of different lenses, which is beneficial to reducing the algorithm difficulty of image stitching and synthesis, and does not require the use of complex image algorithms; further, by setting the absolute value of the difference between the second field of view area obtained by merging the field of view areas of the multiple telephoto lenses and the first field of view area to be less than the field of view area threshold, it is ensured that the union of the field of view areas fitted by the telephoto lenses can cover most of the field of view areas corresponding to the wide-angle lens, so that zoom close-ups can be performed in most of the field of view areas of the wide-angle lens. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in this application or related technologies, the following briefly introduces the drawings required for use in the embodiments or related technical descriptions. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0029] FIG1 is a schematic diagram of an application scenario of an image acquisition device according to an embodiment of the present application;

[0030] FIG2 is a schematic structural diagram of an image acquisition device according to an embodiment of the present application;

[0031] FIG3 is a schematic diagram of the planar structure of an image acquisition device provided in an embodiment of the present application;

[0032] FIG4 is a schematic structural diagram of an image acquisition device provided in an embodiment of the present application;

[0033] FIG5 is a schematic structural diagram of an image acquisition device provided in an embodiment of the present application;

[0034] FIG6 is a plan view schematic diagram of the field of view area of ​​the image acquisition device provided in an embodiment of the present application;

[0035] FIG7 is a plan view schematic diagram of the field of view area of ​​the image acquisition device provided in an embodiment of the present application;

[0036] FIG8 is a plan view schematic diagram of the field of view area of ​​the image acquisition device provided in an embodiment of the present application;

[0037] FIG9 is a schematic structural diagram of an image acquisition device provided in an embodiment of the present application;

[0038] FIG10 is a schematic structural diagram of an image acquisition device provided in an embodiment of the present application;

[0039] FIG11 is a schematic structural diagram of an image acquisition device provided in an embodiment of the present application;

[0040] FIG12 is a schematic structural diagram of a terminal provided in an embodiment of the present application;

[0041] FIG13 is a flow chart of an image acquisition method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0042] To make the objectives, technical solutions, and advantages of this application more clear, the following will clearly and completely describe the technical solutions of this application in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of this application, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0043] The terms "including" and "having," and any variations thereof, in the specification and claims of this application and the accompanying drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or modules is not limited to the listed steps or modules, but may optionally include steps or modules not listed, or may optionally include other steps or modules inherent to the process, method, product, or apparatus.

[0044] It should be noted that the terms "first" and "second" used in this application are merely used to distinguish similar objects and do not represent a specific ordering of the objects. It is understood that the terms "first" and "second" may interchangeably represent a specific order or precedence, where permitted. It should be understood that the objects distinguished by "first" and "second" may interchangeably represent a specific order or precedence, where appropriate, such that the embodiments of the present application described herein can be implemented in an order other than that described or illustrated herein.

[0045] In the related art, since telephoto lenses have a relatively long focal length and high clarity, but a small field of view, while wide-angle lenses have a relatively short focal length and low clarity, but a large field of view, in some special scenarios, using either a telephoto lens or a wide-angle lens alone cannot meet the needs of users. Wide-angle lenses and telephoto lenses can be integrated into the same image acquisition device. A wider imaging range can be obtained through a wide-angle lens. However, because the imaging magnification of the central field of view and the edge field of view of a wide-angle lens is different, there will be image distortion problems at the edge of the image after imaging. If the light barrier of a wide-angle lens is set too large, stray light entering can easily cause interference and cause light spots and light fog problems. When imaging is performed together with a telephoto lens and a wide-angle lens, due to the overlapping imaging areas between multiple lenses, image information overlap will occur in the overlapping imaging areas, resulting in image information loss and image distortion. In order to prevent image distortion, it is necessary to interrupt the shooting for a certain period of time, thereby lengthening the imaging time and failing to meet the real-time performance of video conferencing.

[0046] Next, please refer to FIG1 , which is a schematic diagram of an application scenario of an image acquisition device provided by an exemplary embodiment of the present application.

[0047] As shown in Figure 1, the image acquisition device 100 provided in the embodiment of the present application is suitable for video conferencing scenarios, which include but are not limited to conference rooms, meeting rooms, classrooms, rooms and other places. By setting the image acquisition device 100 at a preset position in the video conferencing scene, the wide-angle lens in the image acquisition device 100 covers the main area of ​​the conference scene, and the field of view area obtained by merging the field of view areas of multiple telephoto lenses is roughly the same as the field of view area obtained by the wide-angle lens, that is, the telephoto lens can achieve a close-up of the target in the area covered by the wide-angle lens, which can not only cover most of the field of view in the scene, but also provide a clear close-up of the people in the scene.

[0048] Furthermore, the image acquisition device provided in the embodiment of the present application can also be applied to a remote video conferencing system to establish a network connection between at least two terminals participating in a remote conference, so that people in different locations can hold a remote conference through the remote video conferencing system.

[0049] Next, please refer to FIG2 , which shows a schematic structural diagram of an image acquisition device provided in an embodiment of the present application. The device 200 includes a wide-angle lens 210 and multiple telephoto lenses 220 .

[0050] The wide-angle lens 210 is used to obtain a first field of view area;

[0051] Multiple telephoto lenses 220 are arranged symmetrically with respect to the center of the wide-angle lens 210. The optical axes S of the multiple telephoto lenses 220 intersect with the optical axis A of the wide-angle lens 210 at the same virtual optical center O2. The absolute value of the difference between the second field of view area obtained by merging the field of view areas of the multiple telephoto lenses 220 and the first field of view area is less than the field of view area threshold.

[0052] Specifically, the wide-angle lens 210 and the telephoto lens 220 are both lenses with fixed focal length and fixed field of view. The parameters of the wide-angle lens 220 and the telephoto lens 210 are selected according to the video conferencing scenario in which the device is used.

[0053] Specifically, the area captured by the wide-angle lens 220 is the first field of view area, as shown in the thin solid line area in Figure 2. The size of the first field of view area captured by the wide-angle lens 210 is positively correlated with the field of view angle of the selected wide-angle lens. The field of view angle of the wide-angle lens 210 is greater than the field of view angle of the telephoto lens. The resulting first field of view area should cover most areas of the conference scene. Each telephoto lens 220 captures a corresponding telephoto field of view area, as shown in the thick solid line area in Figure 2. The field of view areas of multiple telephoto lenses are combined and fitted to obtain a second field of view area, which can be understood as the union of the field of view areas of multiple telephoto lenses. The size of the second field of view area depends on the field of view angle of each telephoto lens and the position of the virtual optical center. The resulting second field of view area should roughly overlap with the first field of view area.

[0054] For example, taking two telephoto lenses as an example, in combination with the schematic diagram of the planar structure of the image acquisition device provided by the embodiment of the present application shown in FIG3, FIG3 illustrates the projection of the field of view area on the horizontal plane, the telephoto lens 320 and the telephoto lens 330 are arranged on both sides of the wide-angle lens 310 in a centrally symmetrical manner, the telephoto lens 320 and the telephoto lens 330 are at the same distance from the wide-angle lens 310, the optical axes of the telephoto lens 320 and the telephoto lens 330 intersect with the optical axis of the wide-angle lens 310 at the virtual optical center O3, the optical axes of the telephoto lens 320 and the telephoto lens 330 and the optical axis of the wide-angle lens 310 are shown as the dotted lines in FIG3, and the optical axes of the telephoto lens 320 and the telephoto lens 330 are intersected with the optical axis of the wide-angle lens 310 at the virtual optical center O3. The field of view area is shown as the thick solid line area in Figure 3, and the first field of view area of ​​the wide-angle lens 310 is shown as the dotted line area in Figure 3; the first field of view area of ​​the wide-angle lens is denoted as M1, and the second field of view area obtained by fitting the field of view area of ​​the telephoto lens is denoted as M2. The difference between M1 and M2 is calculated. The smaller the difference between M1 and M2, the closer the first field of view area of ​​the wide-angle lens is to the second field of view area obtained by fitting the telephoto lens, so that the telephoto lens can magnify the target within most of the field of view area of ​​the wide-angle lens; among them, the field of view area threshold can be set according to the scale of the conference scene used and the parameters of the selected lens, and the embodiment of the present application does not limit this.

[0055] Optionally, the overlap rate of the second field of view area M2 obtained by fitting the first field of view area M1 of the wide-angle lens and the field of view area of ​​the telephoto lens relative to the first field of view area of ​​the wide-angle lens can be calculated, and the intersection of the first field of view area M1 and the second field of view area M2 is calculated and recorded as M1∩M2. The overlap rate relative to the first field of view area of ​​the wide-angle lens is (M1∩M2) / M2. According to the size of the overlap rate, the proportion of the first field of view area of ​​the wide-angle lens covered by the telephoto lens can be judged. If the overlap rate is lower than the set overlap rate threshold, it indicates that the field of view angle of the telephoto lens does not meet the requirements.

[0056] It is understandable that the field of view and focal length of the telephoto lens, and the field of view and focal length of the wide-angle lens can be determined by optical simulation. The field of view and focal length of the wide-angle lens and the telephoto lens depend on the expected spatial size of the video conferencing scene. If the space is large, a wide-angle lens with a larger field of view is required to cover the video conferencing scene. If the space is small, a wide-angle lens with a smaller field of view is required. Similarly, the larger the spatial scene, the longer the focal length of the telephoto lens, the smaller the field of view of the telephoto lens. In order to match the field of view areas corresponding to the field of view of the telephoto lens and the wide-angle lens, the number of telephoto lenses can also be increased accordingly.

[0057] In one embodiment, the multiple telephoto lenses may be arranged in a ring around the wide-angle lens and be symmetrical around the center of the wide-angle lens.

[0058] For example, please refer to Figure 4, which is a structural schematic diagram of an image acquisition device provided in an embodiment of the present application. Taking four telephoto lenses arranged in a ring around a wide-angle lens as an example, the device 400 includes a telephoto lens 420, a telephoto lens 430, a telephoto lens 440, a telephoto lens 450 and a wide-angle lens 410.

[0059] Specifically, the distance between telephoto lens 420 and the axis O of wide-angle lens 410 is AO, the distance between telephoto lens 430 and the axis O of wide-angle lens 410 is BO, the distance between telephoto lens 440 and the axis O of wide-angle lens 410 is CO, and the distance between telephoto lens 450 and the axis O of wide-angle lens 410 is DO. The optical axes S2, S3, S4, and S5 of telephoto lens 420, 430, 440, and 450 intersect with the optical axis A4 of wide-angle lens 410 at the same virtual optical center O4. Because the multiple telephoto lenses are arranged in a ring around the wide-angle lens and are symmetrical around the center of the wide-angle lens, the distance AO is equal to the distance CO, and the distance BO is equal to the distance DO. Among them, the distance AO, the distance CO and the distance BO, the distance DO may not be equal, the optical axes of the telephoto lenses 420 and 440 are at the same angle as the optical axis of the wide-angle lens 410, and the optical axes of the telephoto lenses 430 and 450 are at the same angle as the optical axis of the wide-angle lens.

[0060] Optionally, when the distances AO, CO, BO and DO are all equal, the angles between the optical axes of telephoto lens 420, telephoto lens 430, telephoto lens 440 and telephoto lens 450 and the optical axis of the wide-angle lens are all the same. At this time, the axes of telephoto lens 420, telephoto lens 430, telephoto lens 440 and telephoto lens 450 are located on the same circle with the wide-angle lens 410 as the axis.

[0061] In one embodiment, the multiple telephoto lenses and the wide-angle lenses are arranged in the same row or column and are symmetrical around the center of the wide-angle lens.

[0062] For example, please refer to Figure 5, which is a structural schematic diagram of an image acquisition device provided in an embodiment of the present application. Taking four telephoto lenses and wide-angle lenses arranged in the same column as an example, the device 500 includes a telephoto lens 520, a telephoto lens 530, a telephoto lens 540, a telephoto lens 550 and a wide-angle lens 510.

[0063] Specifically, the distance between telephoto lens 520 and the axis O' of wide-angle lens 510 is A'O', the distance between telephoto lens 530 and the axis O' of wide-angle lens 510 is B'O', the distance between telephoto lens 550 and the axis O' of wide-angle lens 510 is C'O', and the distance between telephoto lens 550 and the axis O' of wide-angle lens 510 is D'O'. The optical axes S2', S3', S4', and S5' of telephoto lens 520, 530, 540, and 550 intersect with the optical axis A5 of wide-angle lens 510 at the same virtual optical center O5. Because the multiple telephoto lenses and the wide-angle lens are arranged in the same row and symmetrically around the center of the wide-angle lens, the distance A'O is equal to the distance D'O', and the distance B'O' is equal to the distance C'O'. Among them, the distance A'O' and the distance D'O' are both greater than the distance B'O' and the distance C'O', the optical axes of the telephoto lens 520 and the telephoto lens 550 are at the same angle to the optical axis A5 of the wide-angle lens 510, and the optical axes of the telephoto lens 530 and the telephoto lens 550 are at the same angle to the optical axis A5 of the wide-angle lens.

[0064] It can be understood that the multiple telephoto lenses in the image acquisition device provided in the embodiment of the present application can be arranged in a ring shape as shown in Figure 4, or can be arranged in the same row as shown in Figure 5. The embodiment of the present application does not limit the arrangement of the telephoto lenses.

[0065] Optionally, the distance between the telephoto lens and the wide-angle lens should be as small as possible. The specific value depends on the volume of the telephoto lens module and the wide-angle lens module, which is not limited in the embodiment of the present application.

[0066] Preferably, each telephoto lens at the same distance from the wide-angle lens can be set to have the same field of view angle parameter, and each telephoto lens at a different distance from the wide-angle lens can be set to have a different field of view angle parameter, which is not limited in this embodiment of the present application.

[0067] Preferably, similarly, each telephoto lens at the same distance from the wide-angle lens can be set to have the same lens parameters, and each telephoto lens at a different distance from the wide-angle lens can be set to have different lens parameters.

[0068] Preferably, each telephoto lens may be set to have the same field of view angle parameters, and similarly, each wide-angle lens may be set to have the same lens parameters, which is not limited in this embodiment of the present application.

[0069] Optionally, lens parameters include but are not limited to focal length, resolution, frame rate, etc., which are not limited in the embodiments of the present application.

[0070] Optionally, the wide-angle lens and the telephoto lens may be placed on a fixed bracket with a fixed angle, thereby locking the relative positional relationship between the wide-angle lens and the telephoto lens.

[0071] In the embodiment of the present application, a first field of view area is obtained by a wide-angle lens, which can improve the viewing angle coverage in a video conferencing scenario; multiple telephoto lenses are arranged symmetrically relative to the center of the wide-angle lens, and the optical axes of the multiple telephoto lenses intersect with the optical axis of the wide-angle lens at the same virtual optical center, so that the telephoto lens and the wide-angle lens can be integrated to losslessly magnify the picture, thereby ensuring the quality of the collected image, and will not cause image distortion due to different focusing information of different lenses, and there is no need to use complex image algorithms; further, by setting the absolute value of the difference between the second field of view area obtained by merging the field of view areas of the multiple telephoto lenses and the first field of view area to be less than the field of view area threshold, it is ensured that the union of the field of view areas obtained by fitting the telephoto lenses can cover most of the field of view areas corresponding to the wide-angle lens, so that zoom close-ups can be performed in most of the field of view areas of the wide-angle lens.

[0072] The inventors discovered that an angle exists between the optical axis of the telephoto lens and the optical axis of the wide-angle lens. If the field of view angle of the telephoto lens is less than a certain value, the boundary line of the projection of the field of view of the telephoto lens on the horizontal plane will intersect with the optical axis of the wide-angle lens, which can easily cause the second field of view area obtained by fitting the telephoto lens to have a blind spot far away from the first field of view area of ​​the wide-angle lens. For example, as shown in FIG6 , two telephoto lenses are arranged symmetrically on both sides of the wide-angle lens. The two telephoto lenses have the same field of view angle. The optical axes of the two telephoto lenses and the wide-angle lens intersect at a common virtual optical center O6. Half of the field of view angle of the telephoto lens is θ1, and the angle between the optical axes of the telephoto lens and the wide-angle lens is θ2. Based on the geometric relationship, it is not difficult to determine that θ1 is less than θ2. One edge of the projection of the field of view of the two telephoto lenses on the horizontal plane intersects at point O6'. The second field of view area obtained by fitting thus has a blind spot M3 after extending to a certain distance. Within the blind spot, the telephoto lens cannot magnify the target.

[0073] Based on this, an embodiment of the present application also provides an image acquisition device, in which multiple telephoto lenses are arranged symmetrically relative to the center of the wide-angle lens, the optical axes of the multiple telephoto lenses intersect with the optical axis of the wide-angle lens at the same virtual optical center, and the angle between the optical axis of the telephoto lens and the optical axis of the wide-angle lens is not less than half of the field of view angle of the telephoto lens, and the absolute value of the difference between the second field of view area obtained by merging the field of view areas of the multiple telephoto lenses and the first field of view area is less than the field of view area threshold.

[0074] For example, please refer to Figure 7, which illustrates a planar schematic diagram of the field of view area of ​​an image acquisition device. Taking two telephoto lenses with the same field of view angle as an example, when the angle θ4 between the optical axis of the telephoto lens and the optical axis of the wide-angle lens is exactly equal to half of the field of view angle θ3 of the telephoto lens, one edge of the projection of the field of view area of ​​the two telephoto lenses on the horizontal plane is parallel to each other and parallel to the projection of the optical axis of the wide-angle lens on the horizontal plane, and the edges of the overlapping area of ​​the two telephoto lenses are parallel to the projection of the optical axis of the wide-angle lens on the horizontal plane. At this time, it is just ensured that there is no blind spot in the field of view at a certain distance from the image acquisition device.

[0075] It is understandable that, based on geometric analysis, if the angle between the optical axes of the telephoto lens and the wide-angle lens decreases, then as shown in FIG6 , the edges of the projections of the fields of view of the two telephoto lenses on the horizontal plane intersect at point O6′.

[0076] Therefore, by setting the angle between the optical axis of the telephoto lens and the optical axis of the wide-angle lens to be no less than half of the field of view angle of the telephoto lens, that is, the angle between the optical axis of the telephoto lens and the optical axis of the wide-angle lens should be greater than or equal to half of the field of view angle of the telephoto lens, a blind spot in the field of view at a certain distance from the image acquisition device can be avoided.

[0077] It can be understood that if the scene in which the image acquisition device is used is small, such as only the image of the area between O6' and the image acquisition device in Figure 6 needs to be captured, then even if the angle between the optical axis of the telephoto lens and the optical axis of the wide-angle lens should be less than half of the field of view angle of the telephoto lens, there will be no blind spot in the scene.

[0078] Preferably, the fields of view of each of the two telephoto lenses have an overlapping third field of view, and the width of the projection of the third field of view on the horizontal plane at a preset distance from the device is not less than a field of view width threshold;

[0079] Optionally, the preset distance and the field of view width threshold depend on the video conferencing scenario used, wherein the preset distance depends on the parameters of the wide-angle lens. The longer the focal length of the wide-angle lens, the larger the preset distance. The field of view width threshold depends on the size of the target to be magnified. For example, if the target to be magnified is a speaker, the field of view width threshold should be the shoulder width of an adult. If the target to be magnified is a product to be displayed, the field of view width threshold can be set to the outer dimensions of the product to be displayed. For example, at a distance of 2.5 meters from the image acquisition device, the field of view width threshold cannot be less than 40 cm. This embodiment of the present application is not limited to this.

[0080] For example, as shown in FIG6 , the width of the projection of the third field of view area on the horizontal plane at a preset distance from the device is PQ, and a portion of PQ is in the blind spot M3 of the field of view. At this time, if the target corresponding to PQ is magnified through any telephoto lens, due to the parallax problem, both telephoto lenses cannot capture all the image information of PQ, which may easily cause the image to be fragmented and the target cannot be fully magnified.

[0081] For example, as shown in Figures 7 and 8, Figures 7 and 8 are plan schematic diagrams of the field of view area of ​​the same image acquisition device provided in an embodiment of the present application. Figure 8 illustrates that the target PQ is at a preset distance from the device, and the width of PQ is exactly equal to the field of view width threshold of the two telephoto lenses. At this time, the target PQ can be magnified by any telephoto lens.

[0082] Furthermore, if the width of PQ is greater than the field of view width threshold of the two telephoto lenses, but one end of PQ is located in the field of view area of ​​one of the telephoto lenses, and the other end is completely located in the third field of view area where the two telephoto lenses overlap, then PQ occupies a larger area in the field of view area of ​​one of the telephoto lenses, and the target PQ can be magnified by the telephoto lens with a larger area.

[0083] Therefore, the embodiment of the present application sets the angle between the optical axis of the telephoto lens and the optical axis of the wide-angle lens to be greater than or equal to half of the field of view angle of the telephoto lens, thereby avoiding the existence of a blind spot in the second field of view area obtained by fitting the telephoto lens at a long distance, ensuring that there is an overlapping area between the field of view areas of the telephoto lens, avoiding the parallax problem caused by the blind spot of the field of view, and completely fusing and splicing images within the depth of field range within the overlapping area; by setting the width of the overlapping area at a preset distance from the device to be not less than the field of view width threshold, image distortion caused by the inability of a single telephoto lens to completely magnify the target is avoided, which is conducive to ensuring image integrity and improving imaging quality.

[0084] Next, please refer to Figures 9-10, which are schematic diagrams of an image acquisition device provided in another embodiment of the present application. The device also includes at least one annular rotation mechanism, the rotation axis of each annular rotation mechanism coincides with the optical axis of the wide-angle lens, each annular rotation mechanism includes multiple rotating bases, each rotating base is at the same distance from the axis of the wide-angle lens, and a telephoto lens is provided on each rotating base. The rotating mechanism drives the telephoto lens to rotate around the optical axis of the wide-angle lens through the rotating base.

[0085] Optionally, the telephoto lens is detachably mounted on the corresponding rotating base.

[0086] Specifically, as shown in Figure 9, taking four telephoto lenses as an example, the image acquisition device shown in Figure 9 includes a wide-angle lens 910 located in the center, a telephoto lens 920, a telephoto lens 930, a telephoto lens 940, and a telephoto lens 950. The telephoto lens 920, the telephoto lens 930, the telephoto lens 940, and the telephoto lens 950 are arranged symmetrically around the wide-angle lens 910. The four telephoto lenses are respectively mounted on a rotating base 962, a rotating base 963, a rotating base 964, and a rotating base 965 of a ring-shaped rotating mechanism 960.

[0087] Optionally, the rotating base is fixed relative to the annular rotating mechanism to ensure that the angles between the optical axes of telephoto lens 920 , telephoto lens 930 , telephoto lens 940 , and telephoto lens 950 and the optical axis of wide-angle lens 910 remain unchanged.

[0088] Optionally, the annular rotating mechanism can be mounted on the image acquisition device by snapping, and can be rotated by gear transmission or bearings.

[0089] Alternatively, FIG. 10 shows a schematic diagram of another image acquisition device provided in an embodiment of the present application. Device 1000 includes two annular rotation mechanisms: a telephoto lens 1030 and a telephoto lens 1050 are mounted on annular rotation mechanism 1060, and telephoto lenses 1020 and 1040 are mounted on annular rotation mechanism 1070. Both annular rotation mechanism 1060 and annular rotation mechanism 1070 are perfectly circular and rotate about the axis of a wide-angle lens 1010. The distance between the telephoto lens 1030 mounted on annular rotation mechanism 1060 and the wide-angle lens 1010 is equal to the distance between the telephoto lens 1050 and the wide-angle lens 1010. Similarly, the distance between the telephoto lens 1020 mounted on annular rotation mechanism 1070 and the wide-angle lens 1010 is equal to the distance between the telephoto lens 1040 and the wide-angle lens 1010. The radius of annular rotation mechanism 1060 is greater than the radius of annular rotation mechanism 1070.

[0090] Optionally, the rotation may be clockwise or counterclockwise, which is not limited in the embodiments of the present application.

[0091] It is understandable that several annular rotating mechanisms can be set according to actual use needs, and the embodiments of the present application do not limit this.

[0092] The embodiment of the present application installs the telephoto lens on the annular rotation mechanism, and the annular rotation mechanism can be used to realize the rotation of the telephoto lens relative to the wide-angle lens, which is convenient for adjusting the orientation of the telephoto lens. After rotating the annular rotation mechanism, the projection of the field of view area of ​​the telephoto lens on the horizontal plane changes accordingly, based on which the field of view area of ​​the telephoto lens can be adjusted; by setting up multiple annular rotation mechanisms, the image acquisition device provided by the embodiment of the present application can be used in a stepped conference room with a height difference, avoiding only considering the field of view area of ​​the telephoto lens on the horizontal plane and ignoring the field of view area in the vertical direction, avoiding the blind spot of the field of view in the vertical direction, and being conducive to expanding the application scope of the image acquisition device.

[0093] Next, please refer to Figure 11, which is a structural schematic diagram of an image acquisition device provided in another embodiment of the present application. The device also includes a rotating base, and the telephoto lens is detachably arranged on the rotating base. The plane where the rotation axis of the rotating base is located is perpendicular to the plane where the optical axis of the wide-angle lens is located. The rotating base is used to drive the telephoto lens to rotate around the rotation axis of the rotating base to adjust the angle between the optical axis of the telephoto lens and the optical axis of the wide-angle lens.

[0094] Exemplarily, as shown in FIG11 , taking two telephoto lenses as an example, the device 1100 includes a wide-angle lens 1110 , a telephoto lens 1120 , a telephoto lens 1130 and a rotating base 1140 . It is understandable that for ease of illustration, only one rotating mechanism 1140 is shown in FIG11 .

[0095] Optionally, a through hole is provided on the end face of the rotating base 1140 corresponding to the inner wall of the device 1100, so that it can be rotatably connected to the device by means of a pin, and the rotating base 1140 can also be rotated around the rotation axis R11 by means of a hinge, a rotating shaft, etc.

[0096] It can be understood that the rotation axis R11 is perpendicular to the optical axis space of the wide-angle lens A11, which can be understood as the plane where the rotation axis R11 of the rotating base 1140 is located is perpendicular to the plane where the optical axis A11 of the wide-angle lens 1110 is located.

[0097] Preferably, in order to ensure that the telephoto lens is symmetrically arranged around the optical axis center of the wide-angle lens, and the virtual optical center of the telephoto lens coincides with the virtual optical center of the wide-angle lens on the optical axis of the wide-angle lens, the telephoto lens with the same axial distance from the optical axis of the wide-angle lens can be set to rotate synchronously. It can be understood that when the corresponding telephoto lens is driven to rotate by rotating the base, the rotation angle and rotation direction of the telephoto lens are the same.

[0098] The embodiment of the present application achieves adjustment of the angle between the optical axis of the telephoto lens and the optical axis of the wide-angle lens by mounting each telephoto lens on a rotating base. When adjusting the virtual optical center position of the image acquisition device, the angle between the optical axis of all telephoto lenses and the optical axis of the wide-angle lens can be conveniently adjusted by adjusting the rotating base so that the virtual optical centers coincide.

[0099] Furthermore, an embodiment of the present application also provides a terminal based on the image processing device described in the above embodiment. Please refer to Figure 12, which is a structural diagram of a terminal provided in an embodiment of the present application.

[0100] Specifically, the terminal 1200 includes a housing 1210 and an image processing device 1220 installed in the housing.

[0101] Specifically, the shell 1210 has a cavity 1211, which is used to accommodate the image processing device 1220. The image processing device can be embedded in the cavity 1211 or installed in the cavity 1211 by glue, bayonet, etc. The size of the cavity 1211 depends on the size of the lens module selected by the image processing device 1220.

[0102] It can be understood that the image processing device 1220 includes at least two telephoto lenses and one wide-angle lens. The lenses are used to collect image information, and the side facing the shooting target is the object side. After the image processing device 1220 is embedded in the cavity 1210, the object side end needs to be located on the outside of the shell to collect image information. The other side relative to the object side end is the object side end. The object side end can be set inside the shell 1210 of the terminal 1200.

[0103] It is understandable that the terminal may be an electronic device such as a television or a video conferencing device, and this embodiment of the present application does not limit this.

[0104] Next, with reference to FIG13, the image acquisition method provided by the embodiment of the present application is described by taking the terminal equipped with the above-mentioned device executing the image acquisition method as an example. Specifically, please refer to FIG13, which shows a flow chart of an image acquisition method provided by the embodiment of the present application, and the method includes the following steps:

[0105] S1301: Determine a target to be focused within a first field of view, and obtain a distance between the target to be focused and the device.

[0106] Specifically, the wide-angle lens is the main lens, and the first field of view area is obtained through the main lens.

[0107] Optionally, the target to be focused can be determined by detecting a person's speech, gestures, etc., or the target to be focused can be actively selected.

[0108] Alternatively, the distance between the target and the device can be determined by measuring the proportion of the target's outline within the image. For example, the size of a human face. If the face occupies a larger proportion of the image, the target is closer to the device. The distance between the target and the device can be a straight-line distance or a vertical distance from the device. This distance can be calculated using sensors and algorithms.

[0109] Furthermore, after determining the target to be focused, the target to be focused can be taken in close-up to generate a focused image, also known as a close-up image;

[0110] Understandably, since the magnification of wide-angle lenses and telephoto lenses is limited, the image quality will deteriorate after the magnification exceeds a certain value. Therefore, it is necessary to select a lens corresponding to the distance between the target to be focused and the device to take a close-up of the target to be focused in order to obtain a clear focused image.

[0111] Specifically, if the distance between the target to be focused and the device is less than a first distance threshold, the method includes:

[0112] S1302: Enlarging the target to be focused by using a wide-angle lens to generate a first focused image.

[0113] The first distance threshold depends on the parameters of the wide-angle lens. This parameter is the distance at which the image clarity does not fall below the minimum requirement when the wide-angle lens magnifies the image to the maximum magnification of the wide-angle lens. The clarity of the lens can be evaluated using the modulation transfer function (MTF).

[0114] When the distance between the target to be focused and the device or the lens is lower than the first distance threshold, it is only necessary to magnify the image through the wide-angle lens.

[0115] Specifically, if the distance between the target to be focused and the device is greater than or equal to a first distance threshold and less than a second distance threshold, the method includes:

[0116] S1303 , first magnify the target to be focused by using the wide-angle lens until the magnification of the wide-angle lens reaches a first magnification, then switch to the corresponding telephoto lens to continue magnifying the target to be focused, and generate a second focused image.

[0117] It can be understood that the second distance threshold depends on the parameters of the telephoto lens, which is the distance corresponding to the image clarity not being lower than the minimum requirement when the telephoto lens magnifies the image to the maximum magnification of the telephoto lens.

[0118] When the distance between the target to be focused and the device is greater than or equal to the first distance threshold and less than the second distance threshold, the image within the first field of view is first magnified through the wide-angle lens. After magnification to the maximum magnification of the wide-angle lens, the image magnified to the maximum magnification by the wide-angle lens is mapped to the corresponding telephoto lens, and the target to be focused is magnified again through the telephoto lens.

[0119] Specifically, if the distance between the target to be focused and the device is greater than or equal to a second distance threshold, the method includes:

[0120] S1304 , sequentially magnifying the target to be focused by the wide-angle lens and the telephoto lens until the magnification of the telephoto lens reaches a second magnification, and digitally amplifying the focused image generated by the telephoto lens to generate a third focused image.

[0121] Specifically, for a target to be focused whose distance is greater than or equal to the second distance threshold, steps S1302 and S1303 may be referred to to sequentially magnify the target through the wide-angle lens and the telephoto lens, and digitally magnify the target after the target is magnified to the maximum magnification of the telephoto lens.

[0122] Understandably, for targets that are far away, it is difficult to continue to magnify them without losing clarity even through a telephoto lens. Therefore, digital magnification is needed to generate a third focused image to complete a close-up of the target.

[0123] Optionally, the digital amplification method includes but is not limited to a nearest point interpolation algorithm, a bilinear interpolation algorithm, etc., which is not limited in the embodiment of the present application.

[0124] The embodiment of the present application determines the distance between the target to be focused and the device, and then selects the corresponding lens or lens and magnification algorithm to take a close-up of the target to be focused, which can maximize the use of hardware resources. The wide-angle lens and the telephoto lens are used to magnify in sequence, and the large imaging range of the wide-angle lens is used to determine the position of the target to be focused, and then the lens for taking a close-up of the target to be focused is determined. The combination of the wide-angle lens and the telephoto lens can achieve a close-up of the target without sacrificing image clarity, which is conducive to improving imaging quality.

[0125] The present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method of any of the aforementioned embodiments. The computer-readable storage medium may include, but is not limited to, any type of disk, including a floppy disk, an optical disk, a DVD, a CD-ROM, a microdrive, a magneto-optical disk, a ROM, a RAM, an EPROM, an EEPROM, a DRAM, a VRAM, a flash memory device, a magnetic card or an optical card, a nanosystem (including a molecular memory IC), or any type of medium or device suitable for storing instructions and / or data.

[0126] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, or of course, by hardware. Based on this understanding, the above technical solution, in essence, or the part that contributes to the relevant technology, can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or certain parts of the embodiments.

[0127] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. An image acquisition device for video conferencing, wherein: include: A wide-angle lens, wherein the wide-angle lens is used to obtain a first field of view; A plurality of telephoto lenses are arranged symmetrically with respect to the center of the wide-angle lens, the optical axes of the plurality of telephoto lenses intersect with the optical axis of the wide-angle lens at a same virtual optical center, and an absolute value of a difference between a second field of view area obtained by combining the field of view areas of the plurality of telephoto lenses and the first field of view area is less than a field of view area threshold.

2. The device according to claim 1, wherein: The angle between the optical axis of the telephoto lens and the optical axis of the wide-angle lens is not less than half of the field of view of the telephoto lens.

3. The device according to claim 1, wherein: The telephoto lens at the same distance as the wide-angle lens has the same field of view.

4. The device according to claim 1, wherein: All of the telephoto lenses have the same field of view.

5. The device according to claim 1, wherein: There is an overlapping third field of view area between the fields of view areas of every two of the telephoto lenses, and the width of the projection of the third field of view area on the horizontal plane at a preset distance from the device is not less than a field of view width threshold.

6. The device according to any one of claims 1 to 5, wherein: The device also includes at least one annular rotating mechanism, the rotation axis of the annular rotating mechanism coincides with the optical axis of the wide-angle lens, the annular rotating mechanism includes a plurality of rotating bases, each of the rotating bases is at the same distance from the axis of the wide-angle lens, each of the rotating bases is provided with a telephoto lens, and the rotating mechanism drives the telephoto lens to rotate around the optical axis of the wide-angle lens through the rotating base.

7. The device according to any one of claims 1 to 5, wherein: The device also includes a rotating base, and the telephoto lens is detachably arranged on the rotating base. The plane where the rotating axis of the rotating base is located is perpendicular to the plane where the optical axis of the wide-angle lens is located. The rotating base is used to drive the telephoto lens to rotate around the rotating axis of the rotating base to adjust the angle between the optical axis of the telephoto lens and the optical axis of the wide-angle lens.

8. A terminal, wherein: include: A housing, the housing comprising a cavity, in which the image acquisition device according to any one of claims 1 to 7 is installed; Wherein, the object side ends of the wide-angle lens and the telephoto lens are both located outside the housing.

9. An image acquisition method based on the image acquisition device according to any one of claims 1 to 7, wherein: include: Determine a target to be focused within the first field of view, and obtain a distance between the target to be focused and the device; If the distance between the target to be focused and the device is less than a first distance threshold, the wide-angle lens is used to The head magnifies the target to be focused to generate a first focused image; If the distance between the target to be focused and the device is greater than or equal to the first distance threshold and less than the second distance threshold, the target to be focused is first magnified by the wide-angle lens until the magnification of the wide-angle lens reaches the first magnification, and then the corresponding telephoto lens is switched to continue to magnify the target to be focused, so as to generate a second focused image; If the distance between the target to be focused and the device is greater than or equal to the second distance threshold, the target to be focused is magnified by the wide-angle lens and the telephoto lens in sequence until the magnification of the telephoto lens reaches the second magnification, and digital magnification is performed on the basis of the focused image generated by the telephoto lens to generate a third focused image.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, wherein: When the computer program is executed by a processor, the steps of the method according to claim 9 are implemented.

Images