GB2528462A

GB2528462A - A camera mounting apparatus, a camera assembly, and a method of mounting cameras

Info

Publication number: GB2528462A
Application number: GB1412950.6A
Authority: GB
Inventors: Sergi Sagas; Joan Bennassar; Antoine Valverde; Gerard Torrent
Original assignee: MediaProduccion SL
Current assignee: MediaProduccion SL
Priority date: 2014-07-22
Filing date: 2014-07-22
Publication date: 2016-01-27
Also published as: GB201412950D0

Abstract

A camera assembly (10) having video cameras (200) received in a camera mounting apparatus (100) and a method of mounting cameras for panoramic video production. The apparatus (100) comprises a plurality of modules (102), each arranged to be rotatable about a first rotational axis, and each arranged to a video camera (200) having a lens in a position in which the entrance pupil of the lens of the received video camera (200) coincides with the first rotational axis.

Description

A Camera Mounting Apparatus, A Camera Assembly, And A Method Of Mounting Cameras The present invention relates to a camera mounting apparatus, a camera assembly, and a method of mounting cameras.

In embodiments, the present invention relates to a camera mounting apparatus for mounting a plurality of video cameras for panoramic video production, a camera assembly for panoramic video production, and a method of mounting video cameras for panoramic video production.

Television coverage of many events of public interest, including sporting events such as football (soccer) matches, typically requires many video cameras at different locations, each requiring a camera operator. In the example of a football (soccer) match, each cameraman operating a camera would follow the action on and off the playing field, either by panning or zooming the video camera to track the ball, players, or spectators as they move around on and off the playing field. Such a broadcast operation necessarily requires a large amount of manpower, equipment, and technical support; all of which adds to the financial costs of producing the broadcast. In particular, equipment such as wide-angle optics used to capture a wide field-of-view of an event can be prohibitively expensive.

In order to reduce the resources required to capture events of public interest for broadcast, it is known to employ systems that use a combination of several cameras, each capturing an overlapping point-of-view of the event. The captured video images are then processed by computationally stitching them together to create a video with images that have a wide field-of-view. Such systems require fewer operators than systems that employ separate cameras, and the wide field-of-view video images obtained have a sufficiently high image quality to enable an editor of the broadcast to select portions of field-of-view of the video images for broadcast, effectively recreating the results that would be obtained from systems with separate cameras.

In a known system that uses a combination of several video cameras, a number of video cameras are arranged in an arc-shaped formation so that each video camera points towards a different point-of-view as compared to an adjacent video camera. The video cameras are also arranged so that the field-of-view of each video camera overlaps with the field-of-view of an adjacent video camera by a small portion. In another known system, a number of video cameras are arranged in a circular formation, directed up towards an inverted polygonal pyramid having mirrored exterior surfaces. The mirrors and cameras are angled so that each video camera captures a section of the horizontal panorama that overlaps by a small portion with the section of the horizontal panorama captured by an adjacent video camera. In these known systems, the captured video images of one video camera are stitched together with the video images captured by an adjacent video camera at the overlapping portion to create panoramic video images that have has a much wider field-of-view as compared to the field-of-view of the video images captured by an individual video camera.

The stitching process is commonly carried out using computer software to create a smooth stitch. However, due to the physical arrangement of the video cameras of these known systems, the videos obtained comprise images that are captured from different perspectives, meaning that overlapping portions of the images from adjacent video cameras do not align. As such, image-matching algorithms are often required to manipulate the overlapping portions so as to match the different parts of the overlapping portions. Such manipulation of the video images generally results in distorted images, rendering the stitched parts of the panoramic image unusable for broadcast.

There is therefore a need for an improved apparatus and for an improved camera assembly for capturing video images for panoramic video production.

According to the first aspect of the present invention, there is provided a camera mounting apparatus for panoramic video production, the apparatus comprising a plurality of modules, each arranged to be rotatable about a first rotational axis, and each arranged to receive a video camera having a lens in a position in which the entrance pupil of the lens of the received video camera coincides with the first rotational axis.

The present invention therefore provides an apparatus that enables a plurality of video cameras to be placed in positions that share a no-parallax point, thereby enabling the video cameras to capture video images that have no parallax. Video images captured in this manner can be stitched together seamlessly and with no distortion to generate panoramic video images for video production.

In some embodiments, each module includes adjustment means for moving a received video camera into said position. Preferably, the adjustment means include rails on which a received video camera moves. Additionally or alternatively, the adjustment means include an adjustment mechanism actuatable to move a received video camera into said position. The apparatus may further comprise an adjustment unit arranged to control the adjustment mechanism. The adjustment unit may be arranged to be communicatively coupled to a computer and may be arranged to control the adjustment mechanism based on signals received from the computer.

In some embodiments, the apparatus further comprises panning means for rotating a received video camera within a module. Preferably, the panning means include a panning mechanism actuatable to rotate a received video camera within the modules.

Additionally or alternatively, the apparatus further comprises a panning unit arranged to control the panning mechanism. The panning unit may be additionally or alternatively arranged to be communicatively coupled to a computer and may be arranged to control the panning mechanism based on signals received from the computer.

In embodiments the modules are arranged in tandem along the first rotational axis.

In embodiments, the modules are arranged to be independently rotatable.

In embodiments, each module includes a casing within which a video camera is housed.

In embodiments, the apparatus further comprises a support stand for fixing the apparatus to a surface.

In embodiments, the apparatus further includes rotatable connections arranged to enable the plurality of modules to rotate about a second rotation axis.

According to the second aspect of the present invention, there is provided a camera mounting apparatus for panoramic video production, the apparatus comprising a first module and a second module, the first module being rotatable about a first axis, the second module being rotatable about a second axis, and each module being arranged to receive a video camera having a lens in a position in which the entrance pupils of the lenses of the received video cameras coincide with a third axis, wherein the first axis, the second axis, and the third axis are parallel.

In an embodiment, the first axis, the second axis, and the third axis are collinear.

According to the third aspect of the present invention, there is provided a camera assembly for panoramic video production, the assembly comprising: a camera mounting apparatus according to the first aspect; and a plurality of video cameras, each having a lens; wherein each video camera is received in one of the plurality of modules and is positioned in which the entrance pupil of its lens coincides with the first rotational axis.

The camera assembly of the present invention enables video cameras to be mounted in a position in which there is no parallax. This enables the video images captured by a video camera that is mounted on the apparatus to be stitched seamlessly and without distortion to the video images captured by another video camera that is mounted on the apparatus.

According to a fourth aspect of the present invention, there is provided a method of mounting video cameras for panoramic video production, comprising: providing a camera mounting apparatus having a plurality of modules, each arranged to be rotatable about a first rotational axis; receiving, in each of the plurality of modules, a video camera having a lens; and positioning the received video cameras in a position in which the entrance pupil of the lens of the received video cameras coincides with the first rotational axis.

Embodiments of the present invention will hereinafter be described by way of examples, with references to the accompanying drawings, in which: Figule 1 is an illustiation of an example of a cameia assembly having a camera mounting apparatus and two video cameras; Figure 2 is an illustration of another example of a camera assembly having a camera mounting apparatus and two video cameras; Figure 3a and 3b are respectively a plan view and a cross-sectional view of a top support element; Figure 4a and 4b are respectively a plan view and a cross-sectional view of a bottom support element; Figure 5 is an illustration of yet another example of a camera assembly having a camera mounting apparatus and two video cameras; Referring to Figure 1, an embodiment of a camera assembly for panoramic video production is shown. The camera assembly 10 broadly comprises a camera mounting apparatus 100 and a number of video cameras 200 mounted on the apparatus 100. In particular, the apparatus 100 shown in Figure 1 is suitable for mounting digital or analogue video cameras. Typically, the video camera 200 comprises a lens and a body provided with film or an image sensor. In the embodiment of the assembly 10 shown in Figure 1, the two video cameras 200 are identical digital video cameras. In addition, the lens of each video camera 200 has the same focal length.

The embodiment of the apparatus 100 shown in Figure 1 comprises two camera mounting modules 102 removably attached together. A rotation fixture 103 such as, but not limited to, a ball-and-socket joint, ball bearings, or any other suitable types of fixture is provided to connect the modules 102 together and each module 102 is arranged to be rotatable about a first rotational axis indicated by the broken line in Figure 1. As shown in this figure, and as referred to hereinafter, the first rotational axis is a vertical rotational axis. However, it will be appreciated that the first rotational axis may have any other suitable orientation.

In some examples of the apparatus 100, the modules 102 are arranged to be rotatable within a plane perpendicular to the vertical rotational axis. Each module 102 is also arranged to receive a video camera 200 and to secure the received video camera 200 in a position (herein after referred to as the no-parallax position) in which the entrance pupil of the lens of the received video camera 200 coincides with the vertical rotational axis.

In use, the modules 102 are each provided with a video camera 200 and are arranged so that one module 102 is atop the other module 102 (i.e. in tandem). Each video camera 200 is secured in its no-parallax position within the module 102. The modules 102 are rotated relative to each other so that the optical axes of the lens of each video camera 200 are angled apart such that the field-of-view of one video camera 200 overlaps with the field-of-view of the other video camera 200.

By securing the video cameras 200 in their no-parallax positions and angling the modules 102 apart in this manner, the video cameras 200 are effectively placed in the same perspective, meaning that the overlapping portions of the video images captured by the two video cameras 200 will appear identical. This allows the video images obtained by the video cameras 200 to be stitched together seamlessly with minimal image manipulation to create panoramic images with no perceptible misalignment. The stitching together of the video images is carried out using suitable computer software.

The vertical displacement between the two video cameras 200 has little effect in practical applications where the video cameras 200 are positioned sufficiently far from the field of interest and can be compensated for using computer software.

Each module 102 of the example of the apparatus 100 shown in Figure 1 includes a frame 104 and a stage 106. The frame 104 provides structural support for the apparatus 100 and provides protection for the video camera 200 received within the frame 104. The stage 106 provides a platform on which the video camera 200 is received. However, it will be appreciated that the video camera 200 can be mounted directly onto the frame 104 of the module 102.

The modules 102 of the apparatus 100 are also provided with adjustment means 108, such as rails or a translation stage, to allow forward, backward and sideways movement of the video camera 200 within the module 102 so that fine adjustment of the position of the video camera can be made easily and conveniently.

Video cameras with identical specifications are often fractionally different in practice.

Fol example, video cameras with lenses having identically specified focal lengths may in practice have focal lengths that are different by a small amount. The adjustment means 108 provide a simple and convenient way to adjust the position of the video camera 200 within the module 102 to take into account this small difference. The adjustment means 108 also allow the apparatus 100 to be conveniently adapted for use with cameras having different specifications. For example, the adjustment means 108 enables an apparatus 100 that is setup for use with a set of video cameras 200 of one focal length to be quickly and simply adapted for use with another set of video cameras 200 of a different focal length.

In an example of this embodiment, the adjustment means 108 are provided on the frame 104 and the stage 106 is provided on the adjustment means 108. In some examples, mounting fixtures (not shown) are provided for fixing the video camera 200 onto the adjustment means 108. The adjustment means 108 include an adjustment mechanism 110. The adjustment mechanism 110 is actuatable, for example manually by an operator of the apparatus 100, to move the adjustment means 108, thereby moving the video camera 200 into the no-parallax position. In examples, the adjustment mechanism 110 comprises knobs and gears coupled in conventional ways to the adjustment means 108. In other examples, the adjustment mechanism 110 comprises simple sliders. Clamping means 112 are optionally provided to hold the adjustment means 108 in position so as to secure the video camera 200 in the no-parallax position.

A support stand 114 is optionally provided to allow the apparatus 100 to be mounted onto a surface. For example, in the embodiment shown in Figure 1, the support stand 114 includes a base 116 connected to a column 118. In turn, the column 118 is connected to one of the modules 102 of the apparatus. Optionally, a rotation fixture is provided for connecting the modules 102 to the support stand 114 to enable the modules 102 to rotate horizontally relative to the support stand 114.

In an alternative example as shown in Figures 2, instead of each module 102 having a frame 104 and a stage 106, each module 102 includes a stage 106 and the apparatus includes a single frame 104. The modules 102 are attached to the frame 104 by way of rotation fixtures (not shown), such as the rotation fixture 103 provided in the example shown in Figure 1, to enable the modules 102 to rotate horizontally relative to each other about a vertical rotational axis when the apparatus 100 is in use.

In the embodiments shown in Figures 1 and 2, the adjustment mechanism 110 is actuatable manually, for example by an operator of the apparatus 100. In some alternative embodiments, the adjustment mechanism 110 is operable electronically by means of an adjustment unit 122. The adjustment unit 122 includes suitable forms of known electrical-mechanical transducer, such as but not limited to motors and piezoelectric transducers, to actuate the adjustment mechanism 110. The adjustment unit 122 is coupled to a power source, such as a battery or mains power supply to provide a source of power to the transducers. The adjustment unit 122 is also coupled to a central processing unit (CPU), which is programmed to transmit signals to the adjustment unit 122 to control the electrical-mechanical transducers, which in turn actuates the adjustment mechanism 110. The adjustment mechanism 110 then moves the adjustment means 108, thereby moving the video cameras 200 into their respective no-parallax positions. For example, the CPU may store data that is indicative of the position of the video cameras 200. In addition, the CPU may also store data corresponding to the characteristics of the lens of the video cameras 200, such as the focal length and the position of entrance pupil. When activated, the CPU transmits signals based on the stored data to control the electrical-mechanical transducers of the adjustment unit 122 to move the adjustment mechanism 110.

In the embodiments shown in Figures 1 and 2, the frame 104 includes a top support element 124 joined by rods with a bottom support element 126. Figures 3a and 3b respectively show a plan view and a cross-sectional view of the top support element 124. Figures 4a and 4b respectively show a plan view and a cross-sectional view of the bottom support element 126. The top support element 124 includes a socket 103a and the bottom support element 126 includes a plug 103b. For example, the socket 103a as shown in Figure 3a is a circular recess and the plug 103b as shown in Figure 4a is a complementarily shaped protrusion. When the apparatus 100 is assembled, the socket 103a and plug 103b form the rotation fixture 103, which allows the modules 102 as shown in Figure 1 to rotate relative to each other. In the embodiment shown in Figure 1, the plug 103a of the bottom support element 126 of the module 102 that is connected to the support stand 114 is arranged to form one part of the rotation fixture in a similar manner as rotation fixture 103.

Panning means 128 are provided, couple to or operating in conjunction with the rotation fixtures 103 and 120, to enable the video camera received within a module 102 to rotate about the vertical rotational axis. The panning means 128 include a panning mechanism, which is separate in some examples or part of the adjustment mechanism in other examples. The panning mechanism is actuatable, for example manually by an operator of the apparatus 100, to move the panning means 128, thereby to enable the video camera 200 received within the module 102 to rotate about the vertical rotational axis. In examples where it is separate, the panning mechanism comprises knobs and gears coupled in conventional ways to the panning means 128 similar to the adjustment mechanism 110. Clamping means (not shown) are optionally provided to hold the panning means 128 in position so as to fix the relative field-of-view of the video cameras 200.

In examples where it is separate, the panning mechanism is alternatively operable electronically by means of a panning unit, similar to the adjustment mechanism 110.

The panning unit, which is part of the adjustment unit 122 in some examples or is separate in other examples, includes suitable forms of known electrical-mechanical transducer, such as but not limited to motors and piezoelectric transducers, to actuate the panning mechanism. The panning unit is coupled to the same power source as the power source to which the adjustment unit 122 is connected or a separate power source to provide a source of power to the transducers. The panning unit is also coupled to a CPU, either the same as that to which the adjustment unit 122 is connected or a separate CPU. The CPU is programmed to transmit signals to the panning unit to control the electrical-mechanical transducers, which in turn actuates the panning mechanism. The panning mechanism then moves the panning means 128, thereby enabling the video cameras 200 to rotate about the vertical rotational axis. For example, the CPU may store data that is indicative of the position of the video cameras 200. In addition, the CPU may also store data corresponding to the characteristics of the lens of the video cameras 200, such as the orientation of the optical axis. When activated, the CPU transmits signals based on the stored data to control the electrical-mechanical transducers of the panning unit to move the panning mechanism.

Referring to Figure 5, each module 102 of some examples of the apparatus 100 is further provided with a casing 130 within which the video camera 200 is housed. The casing 130 provides the video camera 200 with protection against damage such as impact damage and water damage. In some alternative examples (not shown), the camera assembly 10 includes a casing to house the apparatus 100.

Still referring to Figure 5, the frame 104 of some embodiments of the apparatus 100 further includes a tilting mechanism 132 arranged to enable the modules 102 to rotate about a second rotational axis. In some examples, such as that shown in Figure 4, the tilting mechanism 132 includes rotatable connections such as hinges. The frame 104 is connected to the support stand 114 via the hinges to enable the frame 104, including the modules 102, to tilt forwards or backwards. In the example shown in Figure 4, tilting mechanism 132 enables the frame 104 and modules 102 to rotate about a -10 -horizontal axis, i.e. an axis perpendicular to the vertical axis. However, it will be appreciated that the second axis may have any suitable orientation.

In use, video cameras 200 are mounted on the modules 102 of the apparatus 100 to form the assembly 10. The adjustment mechanism 110 is actuated to move the video cameras 200 into their respective no-parallax positions. The panning mechanism 130 is actuated to rotate the video cameras 200 such that the field-of-view of one video camera 200 overlaps with the field-of-view of the other video camera 200 by a small portion.

In the embodiments and examples described above, the apparatus 100 comprises two modules 102. However, it will be appreciated that the apparatus 100 may have more than two modules 102.

In some alternative embodiments, instead of each module 102 being rotatable about a common rotational axis, each module 102 is arranged to be rotatable to about separate parallel axes. Each module 102 of these embodiments are arranged to receive a video camera 20 having a lens such that when the assembly 10 is assembled, the video cameras 200 are in a no-parallax position. This arrangement allows each module 102 to rotate relatively in parallel plains to adjust the angle of view.

The apparatus 100 enables two or more video cameras 200 to be mounted in no-parallax positions and be adjusted so that the video images captured by the video cameras 200 overlap by small portions that are identical. Video images captured by one video camera 200 can then be stitched, seamlessly and without distortion, with the video images captured by another video camera 200 to create panoramic video images to generate panoramic videos for broadcasting.

Embodiments of the present invention have been described with particular reference to the examples illustrated. However, it will be appreciated that variations and modifications may be made to the examples described within the scope of the appending claims.

Claims

-11 -Claims: 1. A camera mounting apparatus fol panoramic video production, the apparatus comprising a plurality of modules, each arranged to be rotatable about a first rotational S axis, and each arranged to receive a video camera having a lens in a position in which the entrance pupil of the lens of the received video camera coincides with the first rotational axis.
2. An apparatus as claimed in claim 1, wherein each module includes adjustment means for moving a received video camera into said position.
3. An apparatus as claimed in claim 2, wherein the adjustment means include rails on which a received video camera moves.
4. An apparatus as claimed in claim 2 or 3, wherein the adjustment means include an adjustment mechanism actuatable to move a received video camera into said position.
5. An apparatus as claimed in claim 3 or 4, wherein the apparatus further comprises an adjustment unit arranged to control the adjustment mechanism.
6. An apparatus as claimed in claim 5, wherein the adjustment unit is arranged to be communicatively coupled to a computer and is arranged to control the adjustment mechanism based on signals received from the computer.
7. An apparatus as claimed in any preceding claim, wherein the apparatus further comprises panning means for rotating a leceived video camera within a module.
8. An apparatus as claimed in claim 7, wherein the panning means include a panning mechanism actuatable to rotate a received video camera within the modules.
9. An apparatus as claimed in claim 7 or 8, wherein the apparatus further comprises a panning unit arranged to control the panning mechanism.

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10. An apparatus as claimed in claim 8 or 9, wherein the panning unit is arranged to be communicatively coupled to a computer and is arranged to control the panning mechanism based on signals received from the computer.
11. An apparatus as claimed in any preceding claim, wherein the modules are arranged in tandem along the first rotational axis.
12. An apparatus as claimed in any preceding claim, wherein the modules are arranged to be independently rotatable. I0
13. An apparatus as claimed in any preceding claim, wherein each module includes a casing within which a video camera is housed.
14. An apparatus as claimed in any preceding claim, wherein the apparatus further comprises a support stand for fixing the apparatus to a surface.
15. An apparatus as claimed in any preceding claim, wherein the apparatus further includes tilting mechanism arranged to enable the plurality of modules to rotate about a second rotational axis.
16. A camera mounting apparatus for panoramic video production, the apparatus comprising a first module and a second module, the first module being rotatable about a first axis, the second module being rotatable about a second axis, and each module being arranged to receive a video camera having a lens in a position in which the entrance pupils of the lenses of the received video cameras coincide with a third axis, wherein the first axis, the second axis, and the third axis are parallel.
17. An apparatus as claimed in claim 16, wherein the first axis, the second axis, and the third axis are collinear.
18. A camera assembly for panoramic video production, the assembly comprising: a camera mounting apparatus according to any previous claim; and a plurality of video cameras, each having a lens; wherein each video camera is received in one of the plurality of modules and is positioned in which the entrance pupil of its lens coincides with the first rotational axis.

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19. A method of mounting cameras for panoramic video production, comprising: providing a camera mounting apparatus having a plurality of modules, each arranged to be rotatable about a first rotational axis; receiving, in each of the plurality of modules, a video camera having a lens; and positioning the received video cameras in a position in which the entrance pupil of the lens of the received video cameras coincides with the first rotational axis.
20. A camera mounting apparatus substantially as described hereinabove with reference to the accompanying drawings. I0
21. A camera assembly substantially as described hereinabove with reference to the accompanying drawings.
22. A method of mounting video cameras substantially as described hereinabove with reference to the accompanying drawings.