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

Abstract

The embodiment of the application discloses an image acquisition device, a terminal, a method and a storage medium for a video conference, and relates to the technical field of camera terminals. The device comprises: a wide-angle lens for acquiring a first field of view area; a plurality of telephoto lenses symmetrically arranged with respect to the center of the wide-angle lens, the optical axes of the plurality of telephoto lenses intersecting with the optical axis of the wide-angle lens at the same virtual optical center, and the absolute value of the difference between the second field of view area obtained by merging the field of view areas of the plurality of telephoto lenses and the first field of view area being less than a field of view area threshold. The image acquisition device of the embodiment of the application combines the wide-angle lens and the telephoto lens, can improve the field of view coverage rate, can also fuse the telephoto lens and the wide-angle lens to perform lossless magnification on the picture, avoids image distortion caused by different focusing information of different lenses based on the setting of the virtual optical center and the field of view area, and can fuse the telephoto lens to perform magnification close-up in most of the field of view area of the wide-angle lens.

Description

Technical Field

[0001] This 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 Technology

[0002] Current video conferencing requires two things in terms of imaging quality: it needs to provide as much panoramic coverage as possible while also delivering clear close-up images of distant targets. Current equipment struggles to achieve both panoramic coverage and image clarity in video conferencing. Wide-angle cameras have a large field of view, allowing them to capture larger scenes, but this reduces the number of pixels per unit area, resulting in significant loss of image clarity when magnifying distant images. Telephoto lenses can obtain sufficiently clear images, but their narrow field of view fails to cover most of the scene.

[0003] In some related technologies, to improve the clarity of important areas in large-scene images captured by wide-angle cameras, more and more equipment manufacturers are equipping electronic devices with multiple lenses, using image matching algorithms to stitch together images captured by multiple lenses. However, existing lenses suffer from image distortion, resulting in low image quality from multiple lenses used to capture different scenes. This makes image stitching algorithms difficult and places high demands on the computing power of image acquisition equipment. Summary of the Invention

[0004] This application provides an image acquisition device, terminal, method, and storage medium for video conferencing, to address the shortcomings of the aforementioned related technologies that cannot simultaneously achieve panoramic image coverage and image clarity. The technical solution is as follows:

[0005] In a first aspect, embodiments of this application provide an image acquisition device for video conferencing, the device comprising:

[0006] A wide-angle lens, used to capture the first field of view;

[0007] 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 with the optical axis of the wide-angle lens at the same virtual optical center. The absolute value of the difference between the second field of view region obtained by merging the field of view regions of the multiple telephoto lenses and the first field of view region is less than the field of view region threshold.

[0008] In one alternative 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 of the field of view of the telephoto lens.

[0009] In one alternative of the first aspect, the telephoto lens at the same distance as the wide-angle lens has the same field of view.

[0010] In one alternative of the first aspect, all telephoto lenses have the same field of view.

[0011] In one alternative of the first aspect, there is an overlapping third field of view between the field of view of every two telephoto lenses, and the width of the projection of the third field of view onto the horizontal plane at a preset distance from the device is not less than the field of view width threshold.

[0012] In one alternative embodiment of the first aspect, the device further includes at least one annular rotating mechanism, the rotation axis of which coincides with the optical axis of the wide-angle lens. The annular rotating mechanism includes multiple rotating bases, each rotating base being equidistant from the axis of the wide-angle lens. A telephoto lens is disposed on each rotating base, and the rotating mechanism drives the telephoto lens to rotate around the optical axis of the wide-angle lens via the rotating bases.

[0013] In one alternative embodiment of the first aspect, the device further includes a rotating base on which a telephoto lens is detachably mounted. The plane containing the rotation axis of the rotating base is perpendicular to the plane containing the optical axis of the wide-angle lens. 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.

[0014] Secondly, embodiments of this application also provide a terminal, the terminal comprising:

[0015] A housing, the housing including a cavity, wherein the image acquisition device provided in any of the first aspects is installed;

[0016] Both the wide-angle and telephoto lenses have their object-side ends located outside the housing.

[0017] Thirdly, embodiments of this application also provide an image acquisition method, applied to the image acquisition device provided in any of the first aspects above, the method comprising the steps of:

[0018] Identify the target to be focused within the first field of view and obtain the distance between the target to be focused and the device;

[0019] If the distance between the target to be focused and the device is less than the first distance threshold, the target to be focused is magnified by the wide-angle lens to generate the first focused image;

[0020] 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. Then, the corresponding telephoto lens is switched to continue magnifying the target to be focused and a second focused image is generated.

[0021] 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 sequentially through the wide-angle lens and the telephoto lens until the magnification of the telephoto lens reaches the second magnification. Based on the focused image generated by the telephoto lens, digital magnification is performed to generate a third focused image.

[0022] Fourthly, this application also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method provided by the first aspect of the embodiments of this application or any implementation thereof.

[0023] The beneficial effects of the technical solutions provided in some embodiments of this application include at least the following:

[0024] This application provides an image acquisition device for video conferencing. It acquires a first field of view using a wide-angle lens, improving the viewing angle coverage in video conferencing scenarios. Multiple telephoto lenses are arranged symmetrically relative to the center of the wide-angle lens, with their optical axes intersecting at the same virtual optical center. This creates an overlapping area between the telephoto and wide-angle lenses, facilitating image synthesis. This allows for lossless magnification of the image by fusing the telephoto and wide-angle lenses, ensuring image quality and preventing distortion due to different focus information from different lenses. This reduces the algorithmic difficulty of image stitching and synthesis, eliminating the need for complex image algorithms. Furthermore, by setting the absolute value of the difference between the second field of view obtained by merging the field of view areas of the multiple telephoto lenses and the first field of view area to be less than a field of view area threshold, it ensures that the union of the field of view areas fitted by the telephoto lenses covers most of the field of view area corresponding to the wide-angle lens, allowing for magnified close-ups within most of the wide-angle lens's field of view area. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in this application or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This application embodiment of the image acquisition device is illustrated in the following diagram:

[0027] Figure 2 This is a schematic diagram of the structure of the image acquisition device according to an embodiment of this application;

[0028] Figure 3 This is a schematic diagram of the planar structure of the image acquisition device provided in the embodiments of this application;

[0029] Figure 4 This is a schematic diagram of the structure of the image acquisition device provided in the embodiments of this application;

[0030] Figure 5 This is a schematic diagram of the structure of the image acquisition device provided in the embodiments of this application;

[0031] Figure 6 This is a schematic diagram of the field of view of the image acquisition device provided in the embodiments of this application;

[0032] Figure 7 This is a schematic diagram of the field of view of the image acquisition device provided in the embodiments of this application;

[0033] Figure 8 This is a schematic diagram of the field of view of the image acquisition device provided in the embodiments of this application;

[0034] Figure 9 This is a schematic diagram of the structure of the image acquisition device provided in the embodiments of this application;

[0035] Figure 10 This is a schematic diagram of the structure of the image acquisition device provided in the embodiments of this application;

[0036] Figure 11 This is a schematic diagram of the structure of the image acquisition device provided in the embodiments of this application;

[0037] Figure 12 This is a schematic diagram of the structure of a terminal provided in an embodiment of this application;

[0038] Figure 13 This is a flowchart illustrating an image acquisition method provided in an embodiment of this application. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0040] The terms "comprising" and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or modules is not limited to the steps or modules listed, but may optionally include steps or modules not listed, or may optionally include other steps or modules inherent to such process, method, product, or apparatus.

[0041] It should be noted that the terms "first" and "second" used in this application are merely to distinguish similar objects and do not represent a specific ordering of the objects. It is understood that "first" and "second" can be interchanged in a specific order or sequence where permitted. It should be understood that the objects distinguished by "first" and "second" can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in an order other than those described or illustrated herein.

[0042] In related technologies, telephoto lenses, due to their long focal length and high sharpness, have a smaller field of view, while wide-angle lenses, with their shorter focal length and lower sharpness, have a larger field of view. In some special scenarios, using either a telephoto or wide-angle lens alone cannot meet the user's needs. Wide-angle and telephoto lenses can be integrated into the same image acquisition device. While a wide-angle lens can achieve a larger imaging range, the difference in magnification between the center and edge fields of view leads to image distortion at the edges. Furthermore, if the aperture of a wide-angle lens is set too large, stray light can easily interfere with the image, causing glare and fogging. When using both telephoto and wide-angle lenses for imaging, overlapping areas between the lenses can cause image information loss and distortion. To prevent image distortion, intermittent shooting is required, increasing the imaging time and failing to meet the real-time requirements of video conferencing.

[0043] Please refer to the following. Figure 1 , Figure 1 This is a schematic diagram illustrating an application scenario of an image acquisition device provided as an exemplary embodiment of this application.

[0044] like Figure 1 As shown, the image acquisition device 100 provided in this application embodiment is applicable to video conferencing scenarios, including but not limited to meeting rooms, conference halls, classrooms, and rooms. By setting the image acquisition device 100 at a preset position in the video conferencing scenario, the wide-angle lens in the image acquisition device 100 covers the main area of ​​the meeting scenario. 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 area covered by the wide-angle lens can be used to achieve close-up of the target through the telephoto lens. It can cover most of the field of view in the scene and also provide clear close-up of the people in the scene.

[0045] Furthermore, the image acquisition device provided in this application embodiment can also be applied to a remote video conferencing system to establish a network connection between at least two terminals participating in a remote meeting, allowing people in different locations to conduct remote meetings through the remote video conferencing system.

[0046] Please see below. Figure 2 , Figure 2 A schematic diagram of the structure of the image acquisition device provided in an embodiment of this application is shown. The device 200 includes a wide-angle lens 210 and multiple telephoto lenses 220.

[0047] Among them, the wide-angle lens 210 is used to acquire the first field of view;

[0048] Multiple telephoto lenses 220 are arranged symmetrically with respect to the wide-angle lens 210. The optical axis S of the multiple telephoto lenses 220 intersects 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 region obtained by merging the field of view regions of the multiple telephoto lenses 220 and the first field of view region is less than the field of view region threshold.

[0049] Specifically, both the wide-angle lens 210 and the telephoto lens 220 are 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.

[0050] Specifically, the area captured by the 220mm wide-angle lens is the first field of view, such as... Figure 2 The area shown by the thin solid line indicates that the size of the first field of view captured by the wide-angle lens 210 is positively correlated with the field of view of the selected wide-angle lens. The field of view of the wide-angle lens 210 is larger than that of the telephoto lens, and the resulting first field of view should cover most of the meeting scene. Each telephoto lens 220 captures its corresponding telephoto field of view, as shown below. Figure 2 The thick solid line area shown represents the second field of view, which is obtained by merging and fitting the field of view areas of multiple telephoto lenses. It can be understood as the union of the field of view areas of multiple telephoto lenses. The size of the second field of view depends on the field of view angle of each telephoto lens and the position of the virtual optical center. The final second field of view should roughly overlap with the first field of view area.

[0051] For example, taking two telephoto lenses as an example, combined Figure 3 The diagram shown is a planar structural schematic of the image acquisition device provided in this embodiment of the application. Figure 3 The diagram illustrates the projection of the field of view onto the horizontal plane. Telephoto lenses 320 and 330 are arranged symmetrically on either side of the wide-angle lens 310. The distances from the wide-angle lens 310 to the telephoto lenses 320 and 330 are the same. The optical axes of the telephoto lenses 320 and 330 intersect the optical axis of the wide-angle lens 310 at a virtual optical center O3. The optical axes of the telephoto lenses 320 and 330 and the optical axis of the wide-angle lens 310 are shown as follows: Figure 3 As shown by the dotted lines, the field of view areas of telephoto lens 320 and telephoto lens 330 are as follows: Figure 3 As shown by the thick solid line area, the first field of view of the wide-angle lens 310 is as follows: Figure 3As shown in the dashed area; the first field of view of the wide-angle lens is denoted as M1, and the second field of view obtained by fitting the field of view 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 of the wide-angle lens is to the second field of view obtained by fitting the telephoto lens, thereby enabling the telephoto lens to magnify the target in most of the field of view of the wide-angle lens. The field of view threshold can be set according to the scale of the meeting scene and the parameters of the selected lens. This application embodiment does not limit this.

[0052] Optionally, the overlap rate of the second field of view M2 obtained by fitting the first field of view M1 of the wide-angle lens and the field of view M2 of the telephoto lens with respect to the first field of view of the wide-angle lens can be calculated. The intersection of the first field of view M1 and the second field of view M2 is calculated and denoted as M1∩M2. Then, the overlap rate with respect to the first field of view of the wide-angle lens is (M1∩M2) / M2. Based on the magnitude of the overlap rate, the proportion of the first field of view of the wide-angle lens covered by the telephoto lens can be determined. If the overlap rate is lower than the set overlap rate threshold, it indicates that the field of view of the telephoto lens does not meet the requirements.

[0053] Understandably, the field of view and focal length of telephoto lenses, as well as those of wide-angle lenses, can be determined through optical simulation. The field of view and focal length of both wide-angle and telephoto lenses depend on the expected size of the video conferencing scene. Larger spaces require wider-angle lenses to cover the scene, while smaller spaces require narrower ones. Similarly, larger scenes necessitate telephoto lenses with longer focal lengths to capture close-ups of distant targets. The longer the focal length, the smaller the field of view. To match the field of view areas of the telephoto and wide-angle lenses, the number of telephoto lenses can be increased accordingly.

[0054] In one embodiment, multiple telephoto lenses can be arranged in a ring around a wide-angle lens and symmetrical about the center of the wide-angle lens.

[0055] For example, please see Figure 4 This is a schematic diagram of the structure of an image acquisition device provided in an embodiment of this 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.

[0056] Specifically, the distance from the axis O of the telephoto lens 420 to the wide-angle lens 410 is AO, the distance from the axis O of the telephoto lens 430 to the wide-angle lens 410 is BO, the distance from the axis O of the telephoto lens 440 to the wide-angle lens is CO, and the distance from the axis O of the telephoto lens 450 to the wide-angle lens 410 is DO. The optical axes S2, S3, S4, and S5 of the telephoto lens 420 and the wide-angle lens 450 intersect with the optical axis A4 of the wide-angle lens 410 at the same virtual optical center O4. Since the multiple telephoto lenses are arranged in a ring around the wide-angle lens and are symmetrical about 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 distances AO and CO can be different from the distances BO and DO. 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.

[0057] Optionally, when the distances AO, CO, BO, and DO are all equal, the angles between the optical axes of the telephoto lenses 420, 430, 440, and 450 and the optical axis of the wide-angle lens are all the same. In this case, the axes of the telephoto lenses 420, 430, 440, and 450 are located on the same circle with the wide-angle lens 410 as the axis.

[0058] In one embodiment, multiple telephoto lenses and wide-angle lenses are arranged in the same row or column and are symmetrical about the center of the wide-angle lens.

[0059] For example, please see Figure 5 This is a schematic diagram of the structure of an image acquisition device provided in an embodiment of this application. Taking four telephoto lenses and a wide-angle lens 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.

[0060] Specifically, the distance from the axis O' of the telephoto lens 520 to the wide-angle lens 510 is A'O', the distance from the telephoto lens 530 to the axis O' of the wide-angle lens 510 is B'O', the distance from the telephoto lens 550 to the axis O' of the wide-angle lens is C'O', and the distance from the telephoto lens 550 to the axis O' of the wide-angle lens 510 is D'O'. The optical axes S2' of the telephoto lens 520, S3' of the telephoto lens 530, S4' of the telephoto lens 540, and S5' of the telephoto lens 550 intersect with the optical axis A5 of the wide-angle lens 510 at the same virtual optical center O5. Since multiple telephoto lenses and wide-angle lenses are arranged in the same column and are symmetrical about 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, distances A'O' and D'O' are both greater than distances B'O' and C'O'. The optical axes of telephoto lenses 520 and 550 are at the same angle as the optical axis A5 of wide-angle lens 510, and the optical axes of telephoto lenses 530 and 550 are at the same angle as the optical axis A5 of wide-angle lens.

[0061] Understandably, the multiple telephoto lenses in the image acquisition device provided in this application embodiment can be as follows: Figure 4 As shown, it is arranged in a ring, or it can be arranged as follows: Figure 5 The arrangement shown is in the same column, and the embodiment of this application does not limit the arrangement of telephoto lenses.

[0062] 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, and this application embodiment does not limit this.

[0063] Preferably, each telephoto lens at the same distance from the wide-angle lens can be configured to have the same field of view parameter, while each telephoto lens at a different distance from the wide-angle lens can be configured to have a different field of view parameter. This application embodiment does not limit this.

[0064] Preferably, similarly, each telephoto lens equidistant from the wide-angle lens can have the same lens parameters, while each telephoto lens at a different distance from the wide-angle lens can have different lens parameters.

[0065] Preferably, each telephoto lens can be set to have the same field of view parameter, and similarly, each wide-angle lens can be set to have the same lens parameter. This application embodiment does not limit this.

[0066] Optionally, lens parameters include, but are not limited to, focal length, resolution, frame rate, etc., and the embodiments of this application do not limit these parameters.

[0067] Alternatively, the wide-angle lens and the telephoto lens can be mounted on a fixed bracket at a fixed angle to lock the relative positional relationship between the wide-angle lens and the telephoto lens.

[0068] In this embodiment, a first field of view is acquired using a wide-angle lens, which improves the viewing angle coverage in video conferencing scenarios. 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. This allows for lossless magnification of the image by fusing the telephoto and wide-angle lenses, ensuring the quality of the acquired image and preventing image distortion due to different focus information from different lenses, without the need for complex image algorithms. Furthermore, by setting the absolute value of the difference between the second field of view obtained by merging the field of view areas of multiple telephoto lenses and the first field of view area to be less than the field of view area threshold, it ensures that the union of the field of view areas fitted by the telephoto lenses can cover most of the field of view area corresponding to the wide-angle lens, thus enabling magnified close-ups within most of the field of view area of ​​the wide-angle lens.

[0069] The inventors discovered that the optical axis of a telephoto lens and the optical axis of a wide-angle lens form an angle. If the field of view of the telephoto lens is less than a certain value, the boundary line of the projection of the telephoto lens's field of view onto the horizontal plane will intersect with the optical axis of the wide-angle lens. This can easily lead to a blind spot in the second field of view obtained by the telephoto lens, located far from the first field of view of the wide-angle lens. For example, such as... Figure 6 As shown, two telephoto lenses are arranged symmetrically on both sides of a wide-angle lens. The two telephoto lenses have the same field of view, and their optical axes intersect at a common virtual optical center O6. Half of the field of view of the telephoto lens is θ1, and the angle between the optical axis of the telephoto lens and the optical axis of the wide-angle lens is θ2. According to geometric relationships, it is easy to determine that θ1 is less than θ2. The edges of the projections of the field of view regions of the two telephoto lenses onto the horizontal plane intersect at point O6'. The second field of view region obtained by fitting thus has a blind spot M3 after extending to a certain distance. Within the blind spot, the target cannot be magnified by the telephoto lens.

[0070] Based on this, this application embodiment also provides an image acquisition device in which multiple telephoto lenses are arranged symmetrically with respect to the center of a wide-angle lens. The optical axes of the multiple telephoto lenses intersect 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 of the telephoto lens. The absolute value of the difference between the second field of view region obtained by merging the field of view regions of the multiple telephoto lenses and the first field of view region is less than the field of view region threshold.

[0071] For example, please refer to Figure 7 , Figure 7An example is provided: a schematic diagram of the field of view of an image acquisition device. Taking two telephoto lenses with the same field of view on both sides of a wide-angle lens 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 θ3 of the telephoto lens, the edges of the projections of the field of view of the two telephoto lenses onto the horizontal plane are parallel to each other and parallel to the projection of the optical axis of the wide-angle lens onto the horizontal plane. The edges of the overlapping areas of the two telephoto lenses are also parallel to the projection of the optical axis of the wide-angle lens onto the horizontal plane. At this time, it is just enough to ensure that there is no blind spot at a certain distance from the image acquisition device.

[0072] Understandably, based on geometric analysis, it's not difficult to conclude that if the angle between the optical axis of a telephoto lens and the optical axis of a wide-angle lens decreases, then... Figure 6 As shown, the edges of the projections of the field of view of the two telephoto lenses onto the horizontal plane intersect at point O6'.

[0073] 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 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 of the telephoto lens, blind spots in the field of view at a certain distance from the image acquisition device can be avoided.

[0074] Understandably, if the image acquisition device is used in a small-scale scenario, such as only requiring image acquisition... Figure 6 The image in the area between O6' and the image acquisition device will not have a blind spot in the scene, even if the angle between the optical axis of the telephoto lens and the optical axis of the wide-angle lens is less than half the field of view of the telephoto lens.

[0075] Preferably, there is an overlapping third field of view area between every two telephoto lenses, and the width of the projection of the third field of view area onto the horizontal plane at a preset distance from the device is not less than the field of view width threshold.

[0076] Optionally, the preset distance and field-of-view threshold depend on the video conferencing scenario. 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 threshold depends on the size of the target to be magnified. For example, if the target is a speaker, the field-of-view threshold should be the shoulder width of an adult. If the target is a product to be displayed, the field-of-view threshold can be set to the outer dimensions of the product. For example, at a distance of 2.5m from the image acquisition device, the field-of-view threshold should not be less than 40cm. This application embodiment does not limit this.

[0077] For example, such as Figure 6As shown, the width of the projection of the third field of view region onto the horizontal plane at a preset distance from the device is PQ. Part of PQ is located in the blind zone M3 of the field of view. If the target corresponding to PQ is magnified by either telephoto lens, due to the parallax problem, neither telephoto lens can capture all the image information of PQ, which can easily lead to the image being fragmented and the target not being fully magnified.

[0078] For example, such as Figure 7 and Figure 8 As shown, Figure 7 and Figure 8 This is a schematic diagram of the field of view of the same image acquisition device provided in the embodiments of this application. Figure 8 The example shows 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 either telephoto lens.

[0079] Furthermore, if the width of PQ is greater than the field width threshold of the two telephoto lenses, but one end of PQ is located within the field of view of one of the telephoto lenses, and the other end is completely located within the third field of view of the two telephoto lenses overlapping, then PQ occupies a larger proportion within the field of view of one of the telephoto lenses, and the target PQ can be magnified by the telephoto lens that occupies a larger proportion.

[0080] Therefore, this embodiment of the 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 the field of view of the telephoto lens. This avoids blind spots in the second field of view obtained by the telephoto lens at long distances, ensures that there are overlapping areas between the field of view areas of the telephoto lenses, avoids parallax problems caused by blind spots, and allows for complete fusion and stitching of images within the depth of field within the overlapping area. By setting the width of the overlapping area at a preset distance from the distance device to be no less than the field of view width threshold, image distortion caused by a single telephoto lens not being able to fully magnify the target is avoided, which helps to ensure image integrity and improve imaging quality.

[0081] Please refer to the following. Figure 9-10 This is a schematic diagram of an image acquisition device provided in another embodiment of this application. The device further includes at least one annular rotating mechanism. The rotation axis of each annular rotating mechanism coincides with the optical axis of the wide-angle lens. Each annular rotating mechanism includes multiple rotating bases. Each rotating base is equidistant from the axis of the wide-angle lens. A telephoto lens is disposed 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.

[0082] Optionally, the telephoto lens can be detachably mounted on the corresponding rotating base.

[0083] Specifically, such as Figure 9 As shown, taking four telephoto lenses as an example, Figure 9 The image acquisition device shown includes a wide-angle lens 910 located in the center, and telephoto lenses 920, 930, 940, and 950. The telephoto lenses 920, 930, 940, and 950 are arranged symmetrically around the wide-angle lens 910. The four telephoto lenses are respectively mounted on the rotating bases 962, 963, 964, and 965 of the ring rotating mechanism 960.

[0084] Optionally, the rotating base is fixed relative to the annular rotating mechanism to ensure that the angle between the optical axis of the telephoto lens 920, telephoto lens 930, telephoto lens 940, and telephoto lens 950 and the optical axis of the wide-angle lens 910 remains unchanged.

[0085] Optionally, the ring-shaped rotating mechanism can be installed on the image acquisition device by a snap-fit, and the rotation can be achieved by gear transmission or bearings.

[0086] Optional, such as Figure 10 The diagram shows another image acquisition device provided in this application embodiment. The device 1000 has two annular rotating mechanisms. Annular rotating mechanism 1060 mounts telephoto lenses 1030 and 1050, while annular rotating mechanism 1070 mounts telephoto lenses 1020 and 1040. Both annular rotating mechanisms 1060 and 1070 are perfect circles and rotate around the axis of wide-angle lens 1010. The distance from the telephoto lens 1030 mounted on annular rotating mechanism 1060 to the wide-angle lens 1010 is equal to the distance from the telephoto lens 1050 to the wide-angle lens 1010. Similarly, the distance from the telephoto lens 1020 mounted on annular rotating mechanism 1070 to the wide-angle lens 1010 is equal to the distance from the telephoto lens 1040 to the wide-angle lens 1010. The radius of annular rotating mechanism 1060 is larger than the radius of annular rotating mechanism 1070.

[0087] Optionally, the rotation can be clockwise or counterclockwise, and this application embodiment does not limit this.

[0088] Understandably, several annular rotating mechanisms can be set according to actual usage needs, and this application embodiment does not limit this.

[0089] This embodiment of the application mounts a telephoto lens on a ring-shaped rotating mechanism. This mechanism allows the telephoto lens to rotate relative to the wide-angle lens, facilitating adjustment of the telephoto lens's orientation. After rotating the ring-shaped rotating mechanism, the projection of the telephoto lens's field of view onto the horizontal plane changes accordingly, allowing for adjustment of the telephoto lens's field of view. By setting multiple ring-shaped rotating mechanisms, the image acquisition device provided in this embodiment can be used in tiered conference rooms with varying heights. This avoids neglecting the vertical field of view when only considering the projection of the telephoto lens's field of view onto the horizontal plane, thus avoiding blind spots in the vertical direction and expanding the application range of the image acquisition device.

[0090] Please refer to the following. Figure 11 This is a schematic diagram of the structure of an image acquisition device provided in another embodiment of this application. The device also includes a rotating base, on which a telephoto lens is detachably mounted. The plane on which the rotation axis of the rotating base is located is perpendicular to the plane on which 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 in order to adjust the angle between the optical axis of the telephoto lens and the optical axis of the wide-angle lens.

[0091] For example, such as Figure 11 As shown, 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. Understandably, for ease of demonstration, Figure 11 Only one rotating mechanism 1140 is shown in the figure.

[0092] Optionally, the rotating base 1140 is provided with a through hole on the end face corresponding to the inner wall of the device 1100, so as to be rotatably connected to the device by means of a pin, or the rotating base 1140 can be rotated around the rotation axis R11 by means of hinge, rotating shaft or other means.

[0093] Understandably, the rotation axis R11 is perpendicular to the optical axis of the wide-angle lens A11. This can be understood as the plane containing the rotation axis R11 of the rotating base 1140 being perpendicular to the plane containing the optical axis A11 of the wide-angle lens 1110.

[0094] Preferably, in order to ensure that the telephoto lens is symmetrically arranged around the optical axis center of the wide-angle lens, and that the virtual optical center of the telephoto lens and the virtual optical center of the wide-angle lens coincide on the optical axis of the wide-angle lens, the telephoto lens with the same axial distance as the optical axis of the wide-angle lens can be set to rotate synchronously. This can be understood as the telephoto lens rotating at the same angle and direction of rotation when the corresponding telephoto lens is driven to rotate by the rotating base.

[0095] This embodiment of the application achieves the 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 axes of all telephoto lenses and the optical axes of the wide-angle lens can be easily adjusted by adjusting the rotating base so that the virtual optical centers coincide.

[0096] Furthermore, this application also provides a terminal based on the image processing apparatus described in the above embodiments. Please refer to [link to relevant documentation]. Figure 12 This is a schematic diagram of the structure of a terminal provided in an embodiment of this application.

[0097] Specifically, the terminal 1200 includes a housing 1210 and an image processing device 1220 installed inside the housing.

[0098] Specifically, the housing 1210 has a cavity 1211 for accommodating the image processing device 1220. The image processing device can be embedded in the cavity 1211 or installed in the cavity 1211 by means of glue, bayonet, etc. The size of the cavity 1211 depends on the size of the lens module selected by the image processing device 1220.

[0099] Understandably, the image processing device 1220 includes at least two telephoto lenses and one wide-angle lens. The lens is used to acquire image information, and the side facing the target is the object side. After the image processing device 1220 is embedded in the cavity 1210, the object side needs to be located on the outside of the housing to acquire image information. The other side relative to the object side is the target side. The target side can be set inside the housing 1210 of the terminal 1200.

[0100] Understandably, the terminal can be an electronic device such as a television or video conferencing device, and this application embodiment does not limit this.

[0101] Next, combine Figure 13 Taking a terminal equipped with the aforementioned device as an example to illustrate the image acquisition method provided in this application, the following description will be provided. For details, please refer to [link to relevant documentation]. Figure 13 , Figure 13 The illustration shows a flowchart of an image acquisition method provided in an embodiment of this application. The method includes the following steps:

[0102] S1301, Determine the target to be focused within the first field of view and obtain the distance between the target to be focused and the device.

[0103] Specifically, the wide-angle lens is the main lens, and the primary field of view is obtained through the main lens.

[0104] 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.

[0105] Optionally, the proportion of the target's outline within the image frame can be detected to determine the distance between the target and the device. For example, the size of a face; if the face occupies a large proportion of the image frame, it indicates that the target is close to the device. The distance between the target and the device can be a straight-line distance or a perpendicular distance to the device, and can be calculated using sensors and algorithms.

[0106] Furthermore, after determining the target to be focused, a close-up of the target can be taken to generate a focused image, also known as a close-up image.

[0107] Understandably, since the magnification of both wide-angle and telephoto lenses is limited, the image quality will degrade after the magnification exceeds a certain value. Therefore, it is necessary to select the appropriate lens based on the distance between the target and the device to take a close-up of the target in order to obtain a clear focused image.

[0108] Specifically, if the distance between the target to be focused and the device is less than a first distance threshold, then it includes:

[0109] S1302 magnifies the target to be focused using a wide-angle lens to generate the first focused image.

[0110] The first distance threshold depends on the parameters of the wide-angle lens. These parameters represent the distance at which the image sharpness is not lower than the minimum requirement when the image is magnified to the maximum magnification of the wide-angle lens. The sharpness of the lens can be evaluated using the MTF (modulation transfer function).

[0111] When the distance between the target to be focused and the device or lens is less than the first distance threshold, it is only necessary to magnify the image using a wide-angle lens.

[0112] 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, then it includes:

[0113] S1303 first magnifies the target to be focused using a wide-angle lens until the magnification of the wide-angle lens reaches the first magnification, then switches to the corresponding telephoto lens to continue magnifying the target to be focused, generating a second focused image.

[0114] Understandably, the second distance threshold depends on the parameters of the telephoto lens, which is the distance at which the image sharpness is not lower than the minimum requirement when the telephoto lens magnifies the image to the maximum magnification of the telephoto lens.

[0115] 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 by 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 by the telephoto lens.

[0116] Specifically, if the distance between the target to be focused and the device is greater than or equal to a second distance threshold, then it includes:

[0117] S1304 magnifies the target to be focused sequentially through a wide-angle lens and a telephoto lens until the telephoto lens reaches the second magnification. Based on the focused image generated by the telephoto lens, it performs digital magnification to generate a third focused image.

[0118] Specifically, for a target to be focused at a distance greater than or equal to the second distance threshold, the steps of S1302 and S1303 can be referred to sequentially to magnify it through a wide-angle lens and a telephoto lens, and then digital magnification is performed after magnification to the maximum magnification of the telephoto lens.

[0119] Understandably, for distant targets, even with a telephoto lens, it is difficult to continue magnifying without sacrificing sharpness. Therefore, it is necessary to introduce digital magnification to generate a third focused image and achieve a close-up of the target.

[0120] Optionally, digital amplification methods include, but are not limited to, nearest neighbor interpolation algorithms, bilinear interpolation algorithms, etc., and the embodiments of this application do not limit them.

[0121] This application embodiment determines the distance between the target to be focused and the device, and then selects the corresponding lens or lens and magnification algorithm to zoom in on the target. This can maximize the use of hardware resources. By using a wide-angle lens and a telephoto lens to zoom in sequentially, the position of the target to be focused is determined by the large imaging range of the wide-angle lens, and then the lens to zoom in on the target is determined. Combining a wide-angle lens and a telephoto lens can achieve zoom in on the target without sacrificing image clarity, which is beneficial to improving image quality.

[0122] This application also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the methods in any of the foregoing embodiments. The computer-readable storage medium may include, but is not limited to, any type of disk, including floppy disks, optical disks, DVDs, CD-ROMs, microdrives, as well as magneto-optical disks, ROMs, RAMs, EPROMs, EEPROMs, DRAMs, VRAMs, flash memory devices, magnetic cards or optical cards, nanosystems (including molecular memory ICs), or any type of medium or device suitable for storing instructions and / or data.

[0123] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the parts that contribute to the related technology, can be embodied in the form of software products. These computer software products can be stored in computer-readable storage media, such as ROM / RAM, magnetic disks, optical disks, etc., and include several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or certain parts of the embodiments.

[0124] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. An image acquisition device for video conferencing, characterized in that, include: A wide-angle lens, the wide-angle lens being used to acquire a first field of view; 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 the same virtual optical center. The absolute value of the difference between the second field of view region obtained by merging the field of view regions of the multiple telephoto lenses and the first field of view region is less than the field of view region threshold. There is an overlapping third field of view region between every two field of view regions of the telephoto lenses. The width of the projection of the third field of view region on the horizontal plane at a preset distance from the device is not less than the field of view width threshold.

2. The apparatus according to claim 1, characterized in that, 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 apparatus according to claim 1, characterized in that, The telephoto lens, at the same distance as the wide-angle lens, has the same field of view.

4. The apparatus according to claim 1, characterized in that, All the telephoto lenses mentioned have the same field of view.

5. The apparatus according to any one of claims 1-4, characterized in that, The device further includes at least one annular rotating mechanism, the rotation axis of which coincides with the optical axis of the wide-angle lens. The annular rotating mechanism includes multiple rotating bases, each of which is equidistant from the axis of the wide-angle lens. Each rotating base is provided with a telephoto lens. The annular rotating mechanism drives the telephoto lens to rotate around the optical axis of the wide-angle lens through the rotating bases.

6. The apparatus according to any one of claims 1-4, characterized in that, The device further includes a rotating base, on which the telephoto lens is detachably mounted. The plane containing the rotation axis of the rotating base is perpendicular to the plane containing the optical axis of the wide-angle lens. 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.

7. A terminal, characterized in that, include: A housing, the housing including a cavity, wherein the image acquisition device according to any one of claims 1-6 is installed in the cavity; The object-side ends of both the wide-angle lens and the telephoto lens are located outside the housing.

8. An image acquisition method based on the image acquisition device according to any one of claims 1-6, characterized in that, include: Identify the target to be focused within the first field of view and obtain the 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 target to be focused is magnified by the wide-angle lens 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 magnifying the target to be focused 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 sequentially by the wide-angle lens and the telephoto lens until the magnification of the telephoto lens reaches the second magnification. Based on the focused image generated by the telephoto lens, a third focused image is generated by digital magnification.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in claim 8.

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