Visual tracking of a rotating game show wheel

Abstract

The present disclosure relates to a method and device (102) of tracking a rotating game show wheel (100). In an aspect, a method of tracking a rotating game show wheel (100) is provided. The method comprises capturing (S101) a sequence of images of the rotating game show wheel (100) using an imaging device (102), identifying (S102) at least one distinguishing feature (101) of the rotating game show wheel (100) in each captured image, determining (S103), for each captured image, a rotational angle of the rotating game show wheel (100) relative to a reference angle by matching the identified at least one distinguishing feature (101) to a corresponding feature in a pre-stored set of reference images, each reference image being associated with a known rotational angle, and determining (S104) the rotational speed of the rotating game show wheel (100) from changes in the determined rotational angles in the sequence of captured images over time.

Description

VISUAL TRACKING OF A ROTATING GAME SHOW WHEELTECHNICAL FIELD

[0001] The present disclosure relates to a method and device of tracking a rotating game show wheel.BACKGROUND

[0002] In conventional systems for tracking the rotation of a game show wheel, sensors are commonly employed to determine the rotational angle and speed of the game show wheel.

[0003] Thus, in order to determine the rotational angle and speed of the rotating game show wheel, the game show wheel itself is arranged with one or more sensors capable of providing data indicating the rotational angle and speed of the game show wheel. Such sensors include for example optical sensors, magnetic sensors, inertial sensors, etc., which may suffer from sensitivity to dirt, dust, or other environmental factors, or may introduce limitations in resolution and / or be prone to drift over time, requiring frequent recalibration to maintain accuracy.

[0004] Thus, there is room for improvement in such systems configured to track rotation of a game show wheel.SUMMARY

[0005] One objective is to provide an improved method of tracking a rotating game show wheel.

[0006] This objective is attained in a first aspect by a method of tracking a rotating game show wheel. The method comprises capturing a sequence of images of the rotating game show wheel using an imaging device, identifying at least one distinguishing feature of the rotating game show wheel in each captured image, determining, for each captured image, a rotational angle of the rotating game show wheel relative to a reference angle by matching the identified at least one distinguishing feature to a corresponding feature in a pre-stored set of reference images, each reference image being associated with a known rotational angle, and determining the rotational speed of the rotating game show wheel from changes in the determined rotational angles in the sequence of captured images over time.

[0007] This objective is attained in a second aspect by an imaging device configured to track a rotating game show wheel. The imaging device comprises at least one processing unit configured to cause the imaging device to be operative to capture a sequence of images of the rotating game show wheel, identify at least one distinguishing feature of the rotating game show wheel in each captured image, determine, for each captured image, a rotational angle of the rotating game show wheel relative to a reference angle by matching the identified at least one distinguishing feature to a corresponding feature in a pre-stored set of reference images, each reference image being associated with a known rotational angle, and to determine the rotational speed of the rotating game show wheel from changes in the determined rotational angles in the sequence of captured images over time.

[0008] Thus, a rotational angle and speed of a rotating game show wheel is advantageously determined by controlling an imaging device to capture images of the rotating game show wheel and compare the captured images to pre-stored reference images each having a known rotational angle associated with it. If here is a match, the rotational angle is derived from the corresponding reference image. Beneficially, this is performed without any sensors attached to the rotating game show wheel.

[0009] In an embodiment, feedback is provided related to the determined rotational angle and rotational speed of the rotating game show wheel.

[0010] In an embodiment, the at least one distinguishing feature comprises a graphic symbol arranged at a peripheral section of the game show wheel.

[0011] In an embodiment, image data is rendered at a central section of the game show wheel, the rendered image data being dynamically adapted to the determined rotational angle and rotational speed of the game show wheel.

[0012] In an embodiment, the game show wheel comprises a surface at the central section, on which surface the image data is rendered using chroma keying.

[0013] In an embodiment, the rendering of the image data comprises rendering the image data with motion blur complying with the determined rotational speed of the game show wheel.

[0014] In an embodiment, interpolation is performed between a plurality of reference images to determine the rotational angle with greater precision in case neither of the plurality of reference images is considered to constitute a match.

[0015] In a third aspect, a computer program is provided comprising computerexecutable instructions for causing an imaging device to perform steps recited in the method of the first aspect when the computer-executable instructions are executed on a processing unit included in the imaging device.

[0016] In a fourth aspect, a computer program product is provided comprising a computer readable medium, the computer readable medium having the computer program according to the third aspect embodied thereon.

[0017] Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to "a / an / the element, apparatus, component, means, step, etc." are to be interpreted openly as referring to at least one instance of the element, apparatus, component, means, step, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated.BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Aspects and embodiments are now described, by way of example, with reference to the accompanying drawings, in which:

[0019] Figure 1 illustrates a prior art rotating object in the form of a game show wheel;

[0020] Figure 2 illustrates an imaging device configured to track rotation of a rotating object according to an embodiment;

[0021] Figure 3 illustrates a flow chart of a method of visually tracking rotation of an object according to an embodiment;

[0022] Figure 4 illustrates a game show the wheel being arranged with a green or blue surface at its central section for allowing application of chroma key technique to generate computer graphics on the surface according to an embodiment;

[0023] Figure 5 illustrates a flow chart of a method of visually tracking rotation of an object according to a further embodiment;

[0024] Figure 6 illustrates image data being rendered on a surface at the central section of the game show wheel of Figure 4;

[0025] Figures 7 and 8 illustrate a presenter moving from left to right in front of the game show wheel of Figure 6; and

[0026] Figure 9 illustrates a schematic diagram of an imaging device according to an embodiment.DETAILED DESCRIPTION

[0027] The aspects of the present disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which certain embodiments of the invention are shown.

[0028] These aspects may, however, be embodied in many different forms and should not be construed as limiting; rather, these embodiments are provided by way of example so that this disclosure will be thorough and complete, and to fully convey the scope of all aspects of the invention to those skilled in the art. Like numbers refer to like elements throughout the description.

[0029] As previously mentioned, in conventional systems for tracking the rotation of a game show wheel, sensors are commonly employed to determine the rotational angle and speed of the game show wheel.

[0030] In these conventional systems, the game show wheel itself is arranged with one or more sensors capable of providing data indicating the rotational angle and speed of the game show wheel.

[0031] Such sensors include for instance optical sensors where the rotating game show wheel may be arranged with patterns (e.g., stripes, grids, or perforations) that interact with a light source and a photodetector. The photodetector is positioned on the opposite side of the rotating game show wheel with respect to the light source (or adjacent to the light source for reflective systems) and senses interruptions in the light caused by the patterns on the disk. The detector thus captures interruptions or reflections of light to calculate the rotational angle and speed. Optical sensors typically require high precision in the placement of the patterns and may suffer from sensitivity to dirt, dust, or other environmental factors.

[0032] In another example, magnetic sensors detect changes in magnetic fields caused by rotating magnets or magnetic strips attached to the rotating game show wheel. These systems are robust in harsh environments but require specializedmagnetic materials and precise alignment. Further, magnetic sensors may introduce limitations in resolution, particularly for high-speed rotations.

[0033] In yet an example, inertial sensors such as accelerometers and gyroscopes may be mounted to the rotating game show wheel to measure angular velocity and acceleration. However, inertial sensors are generally prone to drift over time, hence requiring frequent recalibration to maintain accuracy.

[0034] Figure 1 illustrates a rotating game show wheel 100 for which embodiments of the invention maybe implemented. This particular type of wheel 100 is commonly also referred to as a spinning prize wheel, lucky wheel, money wheel, wheel of fortune, etc. This type of game show wheel may typically be used in broadcasted TV game shows or iGaming / live casino applications.

[0035] As can be seen in Figure 1, a peripheral section of the wheel 100 is arranged with graphic symbols 101 in the form of indicated prize money indications and / or symbols such as e.g. clubs, hearts or spades and even pieces of information such as “Bankrupt” or “Lose a turn “. A studio presenter no will typically host the game show / live casino session and cause the wheel 100 to spin. In other words, different types of graphic symbols 101, such as numbers, text, card denominations, etc., are typically fixedly arranged at the peripheral section of the wheel 100.

[0036] Instead of arranging the wheel 100 with sensors as discussed hereinabove, an imaging device such as a camera 102 is placed in front of the wheel 100, as illustrated in Figure 2 showing the camera 102 and the wheel 100 in a top view.

[0037] During a training phase, the camera 102 is operated to capture a sequence of images of the wheel 100 as the wheel is rotating. The number of captured images generally sets angular resolution of the system. For instance, assuming that 3000 images are captured for one full revolution of the wheel 100 with the wheel 100 rotating at a constant speed, then each image represents a change in rotational angle of 36o° / 3ooo = 0.120. In other words, the change in rotational angle between two consecutive images is 0.120.

[0038] For instance, with reference again to Figure 1, assuming that the images are captured of the rotating wheel 100 starting with number 5000 and the associated clubs symbol at the top (i.e. “twelve o’ clock”), then that image maybe associated with a rotational angle of zero and is set as a reference angle. As a result, the immediatelyfollowing images in the sequence are assigned rotational angles of 0.120, 0.240, 0.36°, and so on. For example, a later captured image in the sequence with number 5000 and the associated clubs symbol (being a unique combination for the wheel 100) located at “three o’ clock” is assigned a rotational angle of 90° and a still later captured image in the sequence with the combination of number 5000 and the clubs symbol located at “six o’ clock” is assigned a rotational angle of 180°, and so on.When having passed through a full revolution, the wheel is again positioned with a rotational angle of zero.

[0039] These 3000 reference images and data indicating the rotational angle associated with each image are then stored, e.g. locally in (or in connection to) the camera 102 or at more remote location such as a cloud server 120, to which the reference images maybe transferred wireless or via wire.

[0040] As is understood, interpolation techniques can be applied to create further images from a group of previously captured images.

[0041] Figure 3 illustrates a flow chart of a method of tracking position of a rotating game show wheel according to an embodiment.

[0042] In a first step S101, the camera 102 captures an image of the wheel 100. Any captured images may be filtered before further being processed e.g. to filter out irrelevant colours, highlight more relevant colour tones, enhance the contrast in the image, and so on.

[0043] Thereafter, in S102, at least one distinguishing feature 101 of the wheel is identified in the captured image. With reference to Figure 1, assuming in this example that number 5000 and the associated clubs symbol of the wheel 100 is identified with the wheel in the position illustrated in Figure 1. However, as is understood, any of the unique combinations of numbers and associated symbols may be identified as a distinguishing feature.

[0044] In S103, the rotational angle of the wheel 100 in the currently captured image (i.e. the captured image with number 5000 and the associated clubs symbol in the position illustrated in Figure 1) is determined by comparing the currently captured image to the above-mentioned pre-stored reference images to find a matching image among the reference images.

[0045] Thus, one of the pre-stored reference images will constitute a best match (i.e. the pre-stored reference image most resembling the captured image with which the pre-stored reference images are compared). As a result, the currently captured image is assigned the known rotational angle associated with the matching pre-stored reference image being the pre-stored reference image with number 5000 and the associated clubs symbol of the wheel 100 in the same position as in Figure 1.

[0046] Optionally, when performing the matching, interpolating between a plurality of reference images may be performed to determine the rotational angle with greater precision in case neither of the two reference images gives a “perfect” match.

[0047] This is repeated for each captured image in the sequence of images, wherein each captured image in the sequence is assigned the rotational angle of the pre-stored reference image for which there is match.

[0048] In S104, the rotational speed of the wheel 100 is determined from changes of the determined rotational angles in the sequence of captured images over time.

[0049] Assuming that one image is captured at time ti with a rotational angle of 01 and a subsequent image is captured at time t2 with a rotational angle of 02.

[0050] The rotational speed w is computed as the rate of change of the rotational angle with respect to time:A0 02 — 01a) = — = - At t2 - tl

[0051] Thus, the rotational angle and speed of the wheel 100 is advantageously determined by controlling the camera 102 to capture images of the rotating wheel 100 and comparing the captured images to pre-stored images each having a known rotational angle associated with it. As is understood, this comparison is not necessarily performed at the camera 102 itself, but may e.g. be performed at the cloud server 120.

[0052] Now, it may be desirable to provide feedback related to the determined rotational angle and rotational speed of the rotating game show wheel 100. For instance, such feedback may be utilized by the presenter no to improve his interaction with the game show wheel 100, such as for example with which speed he spins the wheel 100. Hence, rotational angle and speed data relating to historicalrotations or “spins” of the wheel 100 maybe stored at the camera 102 or the cloud server 120. For instance, an presenter no maybe trained to provide an optimal rotational speed of the wheel 100 based on the stored historical rotational speed data.

[0053] In an embodiment, with reference to Figure 4, the wheel 100 is arranged with a green or blue surface 103 at its central section, on which a chroma key technique can be applied for generating computer graphics on the surface 103. Thus, these graphics are visible to a viewer of a broadcast of the wheel 100 being rotated in a studio, but not to the presenter no. As is known, chroma keying is commonly used in e.g. weather broadcasting. The camera 102 maybe capable of controlling the chroma keying process to render graphics on the surface 103. The peripheral section with symbols 101 is retained.

[0054] Hence, in this embodiment, with reference to the flowchart of Figure 5, the camera 102 controls the rendering of graphics on the surface 103 in S105 (using chroma keying) relating to the determined rotational angle and rotational speed of the wheel 100.

[0055] With reference to Figure 6, in an example, image data in the form of graphic symbols 104 is rendered on the surface 103 at the central section of the wheel 100.

[0056] Thus, instead of the structure of the prior art spinning wheel 100 of Figure 1, where the numbers and the associated symbols are fixedly arranged on the wheel 100, it is now possible with the invention to adapt the information 104 rendered at the central surface 103 to the symbols 101 arranged at the peripheral section of the wheel 100. For instance, instead of associating the clubs symbol at twelve o’ clock with number 5000 as in Figure 1, the clubs symbol at twelve o’ clock is now associated with the text “Lemon”. Advantageously, the rendered image data 104 is dynamically adapted to the determined rotational angle and rotational speed of the rotating object such that the symbol is in alignment with its associated symbol. Other texts generated include “Fruit, “Apples”, Easter”, “Christmas”, etc., as shown in Figure 6, along with graphical data patterns in the form of e.g. stars, suns, moons, etc.

[0057] Advantageously, the camera 102 (or the cloud server 120) controls the rendering of the image data 104 on the surface 103 using chroma keying in S105 such that the image data 104 at all times is in alignment with its corresponding symbolioi, even as the rotational speed of the wheel 100 decreases or increases. In other words, the image data 104 is in synchronization with the rotation of the wheel 100. As is understood, any image data can be rendered on the surface 103.

[0058] A further advantage is that when using chroma keying to present the image data 104 on the green / blue surface 103 arranged at the central section of the wheel 100, the wheel 100 does not need to be equipped with a screen or display for rendering the imaged data 104.

[0059] Still a further advantage is that a first set of image data may be provided to viewers of a first operator, while a second set of image data may be provided to viewers of a second operator, and so on. In other words, different operators may render different image data.

[0060] Using chroma keying, as shown in Figures 7 and 8, a person no can pass in front of the wheel 100 without “disappearing” behind the computer-generated graphics being presented to a viewer. This is highly advantageous since in practice, the person needs to rotate the wheel 100 in different directions and in order to do so, the person has to move to alternating sides of the wheel 100. Thus, Figure 7 illustrates the presenter 110 being located at a left-hand side of the wheel 100 while

[0061] Another feature is that shadows from the person can be captured by the chroma keying technique and rendered on top of the computer-generated graphics, which gives a realistic impression.

[0062] In a further embodiment, the image data 104 rendered on the surface 103 is controlled to be rendered with motion blur complying with the rotational speed of the wheel 100. In other words, to viewer, the motional perception of the rendered imaged data 104 should comply with the actual motion of the wheel 100.

[0063] Figure 9 illustrates an imaging device 102 configured to track a rotating object according to an embodiment. The steps of the method performed by the imaging device 102 are in practice performed by a processing unit 105 embodied in the form of one or more microprocessors arranged to execute a computer program 106 downloaded to a storage medium 107 associated with the microprocessor, such as a Random Access Memory (RAM), a Flash memory or a hard disk drive. The processing unit 105 is arranged to cause the imaging device 102 to carry out the method according to embodiments when the appropriate computer program 106comprising computer-executable instructions is downloaded to the storage medium 107 and executed by the processing unit 105. The storage medium 107 may also be a computer program product comprising the computer program 106. Alternatively, the computer program 106 may be transferred to the storage medium 107 by means of a suitable computer program product, such as a Digital Versatile Disc (DVD) or a memory stick. As a further alternative, the computer program 106 maybe downloaded to the storage medium 107 over a network. The processing unit 105 may alternatively be embodied in the form of a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a complex programmable logic device (CPLD), etc. The imaging device 102 further comprises a communication interface 408 (wired or wireless) over which it is configured to transmit and receive data.

[0064] As mentioned, while the imaging device 102 maybe configured to captured images in step S101, a remotely located device such as the cloud server 120 maybe configured to perform one or more of steps S102-S104 and optionally S105. In other words, while the imaging device 102 captures images of the rotating wheel in S102, the captured images maybe sent from the imaging device 102 to the cloud server 120 which performs the steps of identifying (in S102) distinguishing features of the rotating wheel in each captured image, determines (in S103) a rotational angle of the rotating object by matching the identified distinguishing features to corresponding features in a pre-stored set of reference images previously having been transferred from the imaging device 102 to the cloud server 120, and finally determines (in S104) the rotational speed of the rotating wheel from changes in the determined rotational angles in the sequence of captured images over time. Optionally, the cloud server 120 may be configured to rendering (in S105) image data at a central section of the rotating wheel, wherein the rendered image pattern is dynamically adapted to the determined rotational angle and rotational speed of the game show wheel 100. The cloud server 120 would similarly to the imaging device 102 described hereinabove be equipped with a processing unit arranged to cause the cloud server 120 to carry out steps S102-S105, as well as a storage medium accommodating an appropriate computer program comprising computer-executable instructions.

[0065] The aspects of the present disclosure have mainly been described above with reference to a few embodiments and examples thereof. However, as is readilyappreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the invention, as defined by the appended patent claims.

[0066] Thus, while various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

Claims

CLAIMS1. A method of tracking a rotating game show wheel (100), the method comprising:capturing (Sioi) a sequence of images of the rotating game show wheel (100) using an imaging device (102);identifying (S102) at least one distinguishing feature (101) of the rotating game show wheel (100) in each captured image;determining (S103), for each captured image, a rotational angle of the rotating game show wheel (100) relative to a reference angle by matching the identified at least one distinguishing feature (101) to a corresponding feature in a pre-stored set of reference images, each reference image being associated with a known rotational angle; anddetermining (S104) the rotational speed of the rotating game show wheel (100) from changes in the determined rotational angles in the sequence of captured images over time.

2. The method of claim 1, further comprising:providing (S105) feedback related to the determined rotational angle and rotational speed of the rotating game show wheel.

3. The method of claims 1 or 2, the at least one distinguishing feature (101) comprising a graphic symbol arranged at a peripheral section of the game show wheel (100).

4. The method of claims 2 and 3, the providing (S105) of feedback comprising: rendering (S105) image data (104) at a central section (103) of the game show wheel (100), the rendered image data being dynamically adapted to the determined rotational angle and rotational speed of the game show wheel (100).

5. The method of claim 4, the game show wheel (100) comprising a surface (103) at said central section, on which surface (103) the image data (104) is rendered using chroma keying.

6. The method of claims 4 or 5, the rendering (S105) of the image data (104) comprising:rendering (S105) the image data (104) with motion blur complying with the determined rotational speed of the game show wheel (100).

7. The method of any one of the preceding claims, further comprising, when performing the matching:interpolating between a plurality of reference images to determine the rotational angle with greater precision in case neither of the plurality of reference images is considered to constitute a match.

8. A computer program (106) comprising computer-executable instructions for causing an imaging device (102) to perform steps recited in any one of claims 1-7 when the computer-executable instructions are executed on a processing unit (105) included in the imaging device (102).

9. A computer program product comprising a computer readable medium (107), the computer readable medium having the computer program (106) according to claim 8 embodied thereon.

10. An imaging device (102) configured to track a rotating game show wheel (100), the imaging device (102) comprising at least one processing unit (105) configured to cause the imaging device (102) to be operative to:capture (S101) a sequence of images of the rotating game show wheel (100); identify (S102) at least one distinguishing feature (101) of the rotating game show wheel (100) in each captured image;determine (S103), for each captured image, a rotational angle of the rotating game show wheel (100) relative to a reference angle by matching the identified at least one distinguishing feature (101) to a corresponding feature in a pre-stored set of reference images, each reference image being associated with a known rotational angle; and todetermine (S104) the rotational speed of the rotating game show wheel (100) from changes in the determined rotational angles in the sequence of captured images over time.

11. The imaging device (102) of claim 10, further being operative to:provide (S105) feedback related to the determine rotational angle and rotational speed of the rotating game show wheel (100).

12. The imaging device (102) of claims 10 or 11, the at least one distinguishing feature (101) comprising a graphic symbol arranged at a peripheral section of the game show wheel (100).13- The imaging device (102) of claims 10 or 11, further being operative to, upon providing (S105) the feedback:render (S105) image data (104) at a central section (103) of the game show wheel (100), the rendered image data being dynamically adapted to the determined rotational angle and rotational speed of the game show wheel (100).

14. The imaging device (102) of claim 13, the game show wheel (100) comprising a surface (103) at said central section, on which surface (103) the image data (104) is rendered using chroma keying.

15. The imaging device (102) of claims 13 or 14, further being operative to, upon rendering (S105) the image data (104):render (S105) the image data (104) with motion blur complying with the determined rotational speed of the game show wheel (100).

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