Computer vision and mapping for audio applications

[0001] Examples set forth in the present disclosure relate to portable electronic devices, including wearable devices such as eyewear. More particularly, but not by way of limitation, the present disclosure describes computer vision and mapping systems and methods for audio applications, such as playing musical sounds.

[0002] Many types of computers and electronic devices available today, including mobile devices (e.g., smartphones, tablets, and laptops), and wearable devices (e.g., smartglasses, digital eyewear, headwear, headgear, and head-mounted displays), include digital cameras, display screens, and interfaces through which a user can interact with displayed content.

[0015] Various implementations and details are described with reference to an example: a computer vision engine for playing a musical composition on a portable electronic device using a digital color image of a note matrix on a map. A mobile device, such as a smartphone, includes a processor, a memory, a camera, a loudspeaker, and a display screen. The computer vision engine, in an example implementation, includes a mapping module, a color detection module, and a music playback module. The camera captures a color image of the map, including a marker and a note matrix (in rows and columns, similar to standard musical notation, with a note in each field). From the color image, the computer vision engine detects a token color value associated with each field. Each token color value is associated with a sound sample from a specific musical instrument. A global state map is stored in memory, including the token color value and location of each field in the note matrix. The music playback module, for each column, in order, plays the notes associated with one or more the rows, using the corresponding sound sample, according to the global state map.

[0016] The following detailed description includes systems, methods, techniques, instruction sequences, and computing machine program products illustrative of examples set forth in the disclosure. Numerous details and examples are included for the purpose of providing a thorough understanding of the disclosed subject matter and its relevant teachings. Those skilled in the relevant art, however, may understand how to apply the relevant teachings without such details. Aspects of the disclosed subject matter are not limited to the specific devices, systems, and method described because the relevant teachings can be applied or practice in a variety of ways. The terminology and nomenclature used herein is for the purpose of describing particular aspects only and is not intended to be limiting. In general, well-known instruction instances, protocols, structures, and techniques are not necessarily shown in detail.

[0017] The term “coupled” or “connected” as used herein refers to any logical, optical, physical, or electrical connection, including a link or the like by which the electrical or magnetic signals produced or supplied by one system element are imparted to another coupled or connected system element. Unless described otherwise, coupled or connected elements or devices are not necessarily directly connected to one another and may be separated by intermediate components, elements, or communication media, one or more of which may modify, manipulate, or carry the electrical signals. The term “on” means directly supported by an element or indirectly supported by the element through another element integrated into or supported by the element.

[0018] The orientations of the eyewear device, the handheld device, associated components and any other complete devices incorporating a camera and/or an inertial measurement unit such as shown in any of the drawings, are given by way of example only, for illustration and discussion purposes. In operation, the eyewear device may be oriented in any other direction suitable to the particular application of the eyewear device; for example, up, down, sideways, or any other orientation. Also, to the extent used herein, any directional term, such as front, rear, inward, outward, toward, left, right, lateral, longitudinal, up, down, upper, lower, top, bottom, side, horizontal, vertical, and diagonal are used by way of example only, and are not limiting as to the direction or orientation of any camera and/or inertial measurement unit as constructed as otherwise described herein.

[0019] Additional objects, advantages and novel features of the examples will be set forth in part in the following description, and in part will become apparent to those skilled in the art upon examination of the following and the accompanying drawings or may be learned by production or operation of the examples. The objects and advantages of the present subject matter may be realized and attained by means of the methodologies, instrumentalities and combinations particularly pointed out in the appended claims.

[0020] Reference now is made in detail to the examples illustrated in the accompanying drawings and discussed below.

[0021] FIG. 1A is a side view (right) of an example hardware configuration of an eyewear device 100 which includes a touch-sensitive input device or touchpad 181. As shown, the touchpad 181 may have a boundary that is subtle and not easily seen; alternatively, the boundary may be plainly visible and/or include a raised or otherwise tactile edge that provides feedback to the user about the location and boundary of the touchpad 181. In other implementations, the eyewear 100 may include a touchpad on the left side.

[0022] The surface of the touchpad 181 is configured to detect finger touches, taps, and gestures (e.g., moving touches) for use with a GUI displayed by the eyewear, on a display, to allow the user to navigate through and select menu options in an intuitive manner, which enhances and simplifies the user experience.

[0023] Detection of finger inputs on the touchpad 181 can enable several functions. For example, touching anywhere on the touchpad 181 may cause the GUI to display and/or highlight an item on the screen of the image display, which may be projected onto at least one of the optical assemblies 180A, 180B. Double tapping on the touchpad 181 may select an item or icon. Sliding or swiping a finger in a particular direction (e.g., from front to back, back to front, up to down, or down to) may cause the items or icons to slide or scroll in a particular direction; for example, to move to a next item, icon, video, image, page, or slide. Sliding the finger in another direction may slide or scroll in the opposite direction; for example, to move to a previous item, icon, video, image, page, or slide. The touchpad 181 can be virtually anywhere on the eyewear device 100.

[0024] In one example, when the identified finger gesture is a single tap on the touchpad 181, this initiates selection or pressing of a graphical user interface element in the image presented on the image display of the optical assembly 180A, 180B. An adjustment to the image presented on the image display of the optical assembly 180A, 180B based on the identified finger gesture can be a primary action which selects or submits the graphical user interface element on the image display of the optical assembly 180A, 180B for further display or execution.

[0025] As shown, the eyewear 100 includes a right visible-light camera 114B. As further described herein, two cameras 114A, 114B capture image information for a scene from two separate viewpoints. The two captured images may be used to project a three-dimensional display onto a screen for viewing with 3D glasses.

[0026] The eyewear device 100 includes a right optical assembly 180B with an image display to present images, such as depth images. As shown in FIGS. 1A and 1B, the eyewear device 100 includes the right visible-light camera 114B. The eyewear device 100 can include multiple visible-light cameras 114A, 114B that form a passive type of three-dimensional camera, such as stereo camera, of which the right visible-light camera 114B is located on a right chunk 110B. As shown in FIGS. 1C-D, the eyewear device 100 also includes a left visible-light camera 114A.

[0027] Left and right visible-light cameras 114A, 114B are sensitive to the visible-light range wavelength. Each of the visible-light cameras 114A, 114B have a different frontward facing field of view which are overlapping to enable generation of three-dimensional depth images, for example, right visible-light camera 114B depicts a right field of view 111B. Generally, a “field of view” is the part of the scene that is visible through the camera at a particular position and orientation in space. The fields of view 111A and 111B have an overlapping field of view 813. Objects or object features outside the field of view 111A, 111B when the visible-light camera captures the image are not recorded in a raw image (e.g., photograph or picture). The field of view describes an angle range or extent, which the image sensor of the visible-light camera 114A, 114B picks up electromagnetic radiation of a given scene in a captured image of the given scene. Field of view can be expressed as the angular size of the view cone, i.e., an angle of view. The angle of view can be measured horizontally, vertically, or diagonally.

[0028] In an example, visible-light cameras 114A, 114B have a field of view with an angle of view between 15° to 30°, for example 24°, and have a resolution of 480×480 pixels. The “angle of coverage” describes the angle range that a lens of visible-light cameras 114A, 114B or infrared camera 220 (see FIG. 2A) can effectively image. Typically, the camera lens produces an image circle that is large enough to cover the film or sensor of the camera completely, possibly including some vignetting toward the edge. If the angle of coverage of the camera lens does not fill the sensor, the image circle will be visible, typically with strong vignetting toward the edge, and the effective angle of view will be limited to the angle of coverage.

[0029] Examples of such visible-light cameras 114A, 114B include a high-resolution complementary metal-oxide-semiconductor (CMOS) image sensor and a digital VGA camera (video graphics array) capable of resolutions of 640p (e.g., 640×480 pixels for a total of 0.3 megapixels), 720p, or 1080p. Other examples of visible-light cameras 114A, 114B that can capture high-definition (HD) still images and store them at a resolution of 1642 by 1642 pixels (or greater); and/or record high-definition video at a high frame rate (e.g., thirty to sixty frames per second or more) and store the recording at a resolution of 1216 by 1216 pixels (or greater).

[0030] The eyewear device 100 may capture image sensor data from the visible-light cameras 114A, 114B along with geolocation data, digitized by an image processor, for storage in a memory. The left and right raw images captured by respective visible-light cameras 114A, 114B are in the two-dimensional space domain and comprise a matrix of pixels on a two-dimensional coordinate system that includes an X-axis for horizontal position and a Y-axis for vertical position. Each pixel includes a color attribute value (e.g., a red pixel light value, a green pixel light value, and/or a blue pixel light value); and a position attribute (e.g., an X-axis coordinate and a Y-axis coordinate).

[0031] In order to capture stereo images for later display as a three-dimensional projection, the image processor 912 (shown in FIG. 4) may be coupled to the visible-light cameras 114A, 114B to receive and store the visual image information. A timestamp for each image may be added by the image processor 912 or another processor which controls operation of the visible-light cameras 114A, 114B, which act as a stereo camera to simulate human binocular vision. The timestamp on each pair of images allows the images to be displayed together as part of a three-dimensional projection. Three-dimensional projections create an immersive, life-like experience that is desirable in a variety of contexts, including virtual reality (VR) and video gaming.

[0032] FIG. 3 is a diagrammatic depiction of a three-dimensional scene 715, a left raw image 858A captured by a left visible-light camera 114A, and a right raw image 858B captured by a right visible-light camera 114B. The left field of view 111A may overlap, as shown, with the right field of view 111B. The overlapping field of view 813 represents that portion of the image captured by both cameras 114A, 114B. The term ‘overlapping’ when referring to field of view means the matrix of pixels in the generated raw images overlap by thirty percent (30%) or more. ‘Substantially overlapping’ means the matrix of pixels in the generated raw images—or in the infrared image of scene—overlap by fifty percent (50%) or more. As described herein, the two raw images 858A, 858B may be processed to include a timestamp, which allows the images to be displayed together as part of a three-dimensional projection.

[0033] For the capture of stereo images, as illustrated in FIG. 3, a pair of raw red, green, and blue (RGB) images are captured of a real scene 715 at a given moment in time—a left raw image 858A captured by the left camera 114A and right raw image 858B captured by the right camera 114B. When the pair of raw images 858A, 858B are processed (e.g., by the image processor 912), depth images are generated. The generated depth images may be viewed on an optical assembly 180A, 180B of an eyewear device, on another display (e.g., the image display 880 on a mobile device 890), or on a screen.

[0034] The generated depth images are in the three-dimensional space domain and can comprise a matrix of vertices on a three-dimensional location coordinate system that includes an X axis for horizontal position (e.g., length), a Y axis for vertical position (e.g., height), and a Z axis for depth (e.g., distance). Each vertex may include a color attribute (e.g., a red pixel light value, a green pixel light value, and/or a blue pixel light value); a position attribute (e.g., an X location coordinate, a Y location coordinate, and a Z location coordinate); a texture attribute and/or a reflectance attribute. The texture attribute quantifies the perceived texture of the depth image, such as the spatial arrangement of color or intensities in a region of vertices of the depth image.

[0035] In one example, the system described herein includes the eyewear device 100, which includes a frame 105 and a left temple 125A extending from a left lateral side 170A of the frame 105 and a right temple 125B extending from a right lateral side 170B of the frame 105. The eyewear device 100 may further include at least two visible-light cameras 114A, 114B which may have overlapping fields of view. In one example, the eyewear device 100 includes a left visible-light camera 114A with a left field of view 111A, as illustrated in FIG. 3. The left camera 114A is connected to the frame 105 or the left temple 125A to capture a left raw image 858A from the left side of scene 715. The eyewear device 100 further includes a right visible-light camera 114B with a right field of view 111B. The right camera 114B is connected to the frame 105 or the right temple 125B to capture a right raw image 858B from the right side of scene 715.

[0036] FIG. 1B is a top cross-sectional view of a right chunk 110B of the eyewear device 100 of FIG. 1A depicting the right visible-light camera 114B of the camera system, and a circuit board. FIG. 1C is a side view (left) of an example hardware configuration of an eyewear device 100 of FIG. 1A, which shows a left visible-light camera 114A of the camera system. FIG. 1D is a top cross-sectional view of a left chunk 110A of the eyewear device of FIG. 1C depicting the left visible-light camera 114A of the three-dimensional camera, and a circuit board. Construction and placement of the left visible-light camera 114A is substantially similar to the right visible-light camera 114B, except the connections and coupling are on the left lateral side 170A. As shown in the example of FIG. 1B, the eyewear device 100 includes the right visible-light camera 114B and a circuit board 140B, which may be a flexible printed circuit board (PCB). The right hinge 226B connects the right chunk 110B to a right temple 125B of the eyewear device 100. In some examples, components of the right visible-light camera 114B, the flexible PCB 140B, or other electrical connectors or contacts may be located on the right temple 125B or the right hinge 226B.

[0037] The right chunk 110B includes chunk body 211 and a chunk cap, with the chunk cap omitted in the cross-section of FIG. 1B. Disposed inside the right chunk 110B are various interconnected circuit boards, such as PCBs or flexible PCBs, that include controller circuits for right visible-light camera 114B, microphone(s), low-power wireless circuitry (e.g., for wireless short-range network communication via Bluetooth™), high-speed wireless circuitry (e.g., for wireless local area network communication via WiFi).

[0038] The right visible-light camera 114B is coupled to or disposed on the flexible PCB 140B and covered by a visible-light camera cover lens, which is aimed through opening(s) formed in the frame 105. For example, the right rim 107B of the frame 105, shown in FIG. 2A, is connected to the right chunk 110B and includes the opening(s) for the visible-light camera cover lens. The frame 105 includes a front side configured to face outward and away from the eye of the user. The opening for the visible-light camera cover lens is formed on and through the front or outward-facing side of the frame 105. In the example, the right visible-light camera 114B has an outward-facing field of view 111B (shown in FIG. 3) with a line of sight or perspective that is correlated with the right eye of the user of the eyewear device 100. The visible-light camera cover lens can also be adhered to a front side or outward-facing surface of the right chunk 110B in which an opening is formed with an outward-facing angle of coverage, but in a different outwardly direction. The coupling can also be indirect via intervening components.

[0039] As shown in FIG. 1B, flexible PCB 140B is disposed inside the right chunk 110B and is coupled to one or more other components housed in the right chunk 110B. Although shown as being formed on the circuit boards of the right chunk 110B, the right visible-light camera 114B can be formed on the circuit boards of the left chunk 110A, the temples 125A, 125B, or the frame 105.

[0040] FIGS. 2A and 2B are perspective views, from the rear, of example hardware configurations of the eyewear device 100, including two different types of image displays. The eyewear device 100 is sized and shaped in a form configured for wearing by a user; the form of eyeglasses is shown in the example. The eyewear device 100 can take other forms and may incorporate other types of frameworks; for example, a headgear, a headset, or a helmet.

[0041] In the eyeglasses example, eyewear device 100 includes a frame 105 including a left rim 107A connected to a right rim 107B via a bridge 106 adapted to be supported by a nose of the user. The left and right rims 107A, 107B include respective apertures 175A, 175B, which hold a respective optical element 180A, 180B, such as a lens and a display device. As used herein, the term “lens” is meant to include transparent or translucent pieces of glass or plastic having curved and/or flat surfaces that cause light to converge/diverge or that cause little or no convergence or divergence.

[0042] Although shown as having two optical elements 180A, 180B, the eyewear device 100 can include other arrangements, such as a single optical element (or it may not include any optical element 180A, 180B), depending on the application or the intended user of the eyewear device 100. As further shown, eyewear device 100 includes a left chunk 110A adjacent the left lateral side 170A of the frame 105 and a right chunk 110B adjacent the right lateral side 170B of the frame 105. The chunks 110A, 110B may be integrated into the frame 105 on the respective sides 170A, 170B (as illustrated) or implemented as separate components attached to the frame 105 on the respective sides 170A, 170B. Alternatively, the chunks 110A, 110B may be integrated into temples (not shown) attached to the frame 105.

[0043] In one example, the image display of optical assembly 180A, 180B includes an integrated image display. As shown in FIG. 2A, each optical assembly 180A, 180B includes a suitable display matrix 177, such as a liquid crystal display (LCD), an organic light-emitting diode (OLED) display, or any other such display. Each optical assembly 180A, 180B also includes an optical layer or layers 176, which can include lenses, optical coatings, prisms, mirrors, waveguides, optical strips, and other optical components in any combination. The optical layers 176A, 176B, . . . 176N (shown as 176A-N in FIG. 2A and herein) can include a prism having a suitable size and configuration and including a first surface for receiving light from a display matrix and a second surface for emitting light to the eye of the user. The prism of the optical layers 176A-N extends over all or at least a portion of the respective apertures 175A, 175B formed in the left and right rims 107A, 107B to permit the user to see the second surface of the prism when the eye of the user is viewing through the corresponding left and right rims 107A, 107B. The first surface of the prism of the optical layers 176A-N faces upwardly from the frame 105 and the display matrix 177 overlies the prism so that photons and light emitted by the display matrix 177 impinge the first surface. The prism is sized and shaped so that the light is refracted within the prism and is directed toward the eye of the user by the second surface of the prism of the optical layers 176A-N. In this regard, the second surface of the prism of the optical layers 176A-N can be convex to direct the light toward the center of the eye. The prism can optionally be sized and shaped to magnify the image projected by the display matrix 177, and the light travels through the prism so that the image viewed from the second surface is larger in one or more dimensions than the image emitted from the display matrix 177.

[0044] In one example, the optical layers 176A-N may include an LCD layer that is transparent (keeping the lens open) unless and until a voltage is applied which makes the layer opaque (closing or blocking the lens). The image processor 912 on the eyewear device 100 may execute programming to apply the voltage to the LCD layer in order to create an active shutter system, making the eyewear device 100 suitable for viewing visual content when displayed as a three-dimensional projection. Technologies other than LCD may be used for the active shutter mode, including other types of reactive layers that are responsive to a voltage or another type of input.

[0045] In another example, the image display device of optical assembly 180A, 180B includes a projection image display as shown in FIG. 2B. Each optical assembly 180A, 180B includes a laser projector 150, which is a three-color laser projector using a scanning mirror or galvanometer. During operation, an optical source such as a laser projector 150 is disposed in or on one of the temples 125A, 125B of the eyewear device 100. Optical assembly 180B in this example includes one or more optical strips 155A, 155B, . . . 155N (shown as 155A-N in FIG. 2B) which are spaced apart and across the width of the lens of each optical assembly 180A, 180B and/or across a depth of the lens between the front surface and the rear surface of the lens.

[0046] As the photons projected by the laser projector 150 travel across the lens of each optical assembly 180A, 180B, the photons encounter the optical strips 155A-N. When a particular photon encounters a particular optical strip, the photon is either redirected toward the user's eye, or it passes to the next optical strip. A combination of modulation of laser projector 150, and modulation of optical strips, may control specific photons or beams of light. In an example, a processor controls optical strips 155A-N by initiating mechanical, acoustic, or electromagnetic signals. Although shown as having two optical assemblies 180A, 180B, the eyewear device 100 can include other arrangements, such as a single or three optical assemblies, or each optical assembly 180A, 180B may have arranged different arrangement depending on the application or intended user of the eyewear device 100.

[0047] As further shown in FIGS. 2A and 2B, eyewear device 100 includes a left chunk 110A adjacent the left lateral side 170A of the frame 105 and a right chunk 110B adjacent the right lateral side 170B of the frame 105. The chunks 110A, 110B may be integrated into the frame 105 on the respective lateral sides 170A, 170B (as illustrated) or implemented as separate components attached to the frame 105 on the respective sides 170A, 170B. Alternatively, the chunks 110A, 110B may be integrated into temples 125A, 125B attached to the frame 105.

[0048] In another example, the eyewear device 100 shown in FIG. 2B may include two projectors, a left projector 150A (not shown) and a right projector 150B (shown as projector 150). The left optical assembly 180A may include a left display matrix 177A (not shown) and/or a left set of optical strips 155′A, 155′B, . . . 155′N (155 prime, A through N, not shown) which are configured to interact with light from the left projector 150A. Similarly, the right optical assembly 180B may include a right display matrix 177B (not shown) and/or a right set of optical strips 155″A, 155″B, . . . 155″N (155 double-prime, A through N, not shown) which are configured to interact with light from the right projector 150B. In this example, the eyewear device 100 includes a left display and a right display.

[0049] FIG. 4 is a functional block diagram of an example system that includes a wearable device 100 (e.g., an eyewear device), a mobile device 890, and a server system 998 connected via various networks 995 such as the Internet. The system, as shown, includes a low-power wireless connection 925 and a high-speed wireless connection 937 between the eyewear device 100 and a mobile device 890.

[0050] A computer vision engine 600, including a mapping module 601, a color detection module 602, and a music playback module 603, are stored in memory 934 for execution by one of the processors 932, 922 of the eyewear 100. The eyewear device 100 further includes a user input device 991 (e.g., a touch sensor or touchpad 181, as shown in FIG. 1) to receive input from a user.

[0051] The eyewear device 100 includes one or more visible-light cameras 114A, 114B which may be capable of capturing still images and/or video, as described herein. The cameras 114A, 114B may have a direct memory access (DMA) to high-speed circuitry 930. A pair of cameras 114A, 114B may function as a stereo camera, as described herein. The cameras 114A, 114B may be used to capture initial-depth images that may be rendered into three-dimensional (3D) models that are texture-mapped images of a red, green, and blue (RGB) imaged scene. The device 100 may also include a depth sensor 213, which uses infrared signals to estimate the position of objects relative to the device 100. The depth sensor 213 in some examples includes one or more infrared emitter(s) 215 and infrared camera(s) 220.

[0052] The eyewear device 100 further includes two image displays of each optical assembly 180A, 180B (one associated with the left side 170A and one associated with the right side 170B). The eyewear device 100 also includes an image display driver 942, an image processor 912, low-power circuitry 920, and high-speed circuitry 930. The image displays of each optical assembly 180A, 180B are for presenting images, including still images and video. The image display driver 942 is coupled to the image displays of each optical assembly 180A, 180B in order to control the images displayed.

[0053] The components shown in FIG. 4 for the eyewear device 100 are located on one or more circuit boards, for example a PCB or flexible PCB, located in the rims or temples. Alternatively, or additionally, the depicted components can be located in the chunks, frames, hinges, or bridge of the eyewear device 100. Left and right visible-light cameras 114A, 114B can include digital camera elements such as a complementary metal-oxide-semiconductor (CMOS) image sensor, a charge-coupled device, a lens, or any other respective visible or light capturing elements that may be used to capture data, including still images or video of scenes with unknown objects.

[0054] As shown in FIG. 4, high-speed circuitry 930 includes a high-speed processor 932, a memory 934, and high-speed wireless circuitry 936. In the example, the image display driver 942 is coupled to the high-speed circuitry 930 and operated by the high-speed processor 932 in order to drive the left and right image displays of each optical assembly 180A, 180B. High-speed processor 932 may be any processor capable of managing high-speed communications and operation of any general computing system needed for eyewear device 100. High-speed processor 932 includes processing resources needed for managing high-speed data transfers on high-speed wireless connection 937 to a wireless local area network (WLAN) using high-speed wireless circuitry 936. In certain examples, the high-speed processor 932 executes an operating system such as a LINUX operating system or other such operating system of the eyewear device 100 and the operating system is stored in memory 934 for execution. In addition to any other responsibilities, the high-speed processor 932 executes a software architecture for the eyewear device 100 that is used to manage data transfers with high-speed wireless circuitry 936. In certain examples, high-speed wireless circuitry 936 is configured to implement Institute of Electrical and Electronic Engineers (IEEE) 802.11 communication standards, also referred to herein as Wi-Fi. In other examples, other high-speed communications standards may be implemented by high-speed wireless circuitry 936.

[0055] The low-power circuitry 920 includes a low-power processor 922 and low-power wireless circuitry 924. The low-power wireless circuitry 924 and the high-speed wireless circuitry 936 of the eyewear device 100 can include short range transceivers (Bluetooth™) and wireless wide, local, or wide-area network transceivers (e.g., cellular or WiFi). Mobile device 890, including the transceivers communicating via the low-power wireless connection 925 and the high-speed wireless connection 937, may be implemented using details of the architecture of the eyewear device 100, as can other elements of the network 995.

[0056] Memory 934 includes any storage device capable of storing various data and applications, including, among other things, camera data generated by the left and right visible-light cameras 114A, 114B, the infrared camera(s) 220, the image processor 912, and images generated for display by the image display driver 942 on the image display of each optical assembly 180A, 180B. Although the memory 934 is shown as integrated with high-speed circuitry 930, the memory 934 in other examples may be an independent, standalone element of the eyewear device 100. In certain such examples, electrical routing lines may provide a connection through a chip that includes the high-speed processor 932 from the image processor 912 or low-power processor 922 to the memory 934. In other examples, the high-speed processor 932 may manage addressing of memory 934 such that the low-power processor 922 will boot the high-speed processor 932 any time that a read or write operation involving memory 934 is needed.

[0057] As shown in FIG. 4, the high-speed processor 932 of the eyewear device 100 can be coupled to the camera system (visible-light cameras 114A, 114B), the image display driver 942, the user input device 991, and the memory 934. As shown in FIG. 5, the CPU 830 of the mobile device 890 may be coupled to a camera system 870, a mobile display driver 882, a user input layer 891, and a memory 840A.

[0058] The eyewear device 100 can perform all or a subset of any of the functions described herein which result from the execution of the programming (e.g., the computer vision engine 600, as described herein) which is stored in the memory 934 and executed by one of the processors 932, 922 of the eyewear device 100. The mobile device 890 can perform all or a subset of any of the functions described herein which result from the execution of the programming in the flash memory 840A by the CPU 830 of the mobile device 890. Functions can be divided such that the mobile device 890 collects motion data using a face-tracking application and sends it to the eyewear device 100, which performs the rendering functions relative to the display of a virtual object.

[0059] The server system 998 may be one or more computing devices as part of a service or network computing system, for example, that include a processor, a memory, and network communication interface to communicate over the network 995 with an eyewear device 100 and a mobile device 890.

[0060] The output components of the eyewear device 100 include visual elements, such as the left and right image displays associated with each lens or optical assembly 180A, 180B as described in FIGS. 2A and 2B (e.g., a display such as a liquid crystal display (LCD), a plasma display panel (PDP), a light emitting diode (LED) display, a projector, or a waveguide). The eyewear device 100 may include a user-facing indicator (e.g., an LED, a loudspeaker, or a vibrating actuator), and/or an outward-facing signal (e.g., an LED, a loudspeaker). The image displays of each optical assembly 180A, 180B are driven by the image display driver 942. In some example configurations, the output components of the eyewear device 100 further include additional indicators such as audible elements (e.g., loudspeakers), tactile components (e.g., an actuator such as a vibratory motor to generate haptic feedback), and other signal generators. For example, the device 100 may include a user-facing set of indicators, and an outward-facing set of signals. The user-facing set of indicators are configured to be seen or otherwise sensed by the user of the device 100. For example, the device 100 may include an LED display positioned so the user can see it, a loudspeaker positioned to generate a sound the user can hear, or an actuator to provide haptic feedback the user can feel. The outward-facing set of signals are configured to be seen or otherwise sensed by an observer near the device 100. Similarly, the device 100 may include an LED, a loudspeaker, or an actuator that is configured and positioned to be sensed by an observer.

[0061] The input components of the eyewear device 100 may include alphanumeric input components (e.g., a touch screen or touchpad configured to receive alphanumeric input, a photo-optical keyboard, or other alphanumeric-configured elements), pointer-based input components (e.g., a mouse, a touchpad, a trackball, a joystick, a motion sensor, or other pointing instruments), tactile input components (e.g., a button switch, a touch screen or touchpad that senses the location and/or force of touches or touch gestures, or other tactile-configured elements), and audio input components (e.g., a microphone), and the like. The mobile device 890 and the server system 998 may include alphanumeric, pointer-based, tactile, audio, and other input components.

[0062] In some examples, the eyewear device 100 includes a collection of motion-sensing components referred to as an inertial measurement unit 972. The motion-sensing components may be micro-electro-mechanical systems (MEMS) with microscopic moving parts, often small enough to be part of a microchip. The inertial measurement unit (IMU) 972 in some example configurations includes an accelerometer, a gyroscope, and a magnetometer. The accelerometer senses the linear acceleration of the device 100 (including the acceleration due to gravity) relative to three orthogonal axes (x, y, z). The gyroscope senses the angular velocity of the device 100 about three axes of rotation (pitch, roll, yaw). Together, the accelerometer and gyroscope can provide position, orientation, and motion data about the device relative to six axes (x, y, z, pitch, roll, yaw). The magnetometer, if present, senses the heading of the device 100 relative to magnetic north. The position of the device 100 may be determined by location sensors, such as a GPS receiver, one or more transceivers to generate relative position coordinates, altitude sensors or barometers, and other orientation sensors. Such positioning system coordinates can also be received over the wireless connections 925, 937 from the mobile device 890 via the low-power wireless circuitry 924 or the high-speed wireless circuitry 936.

[0063] The IMU 972 may include or cooperate with a digital motion processor or programming that gathers the raw data from the components and compute a number of useful values about the position, orientation, and motion of the device 100. For example, the acceleration data gathered from the accelerometer can be integrated to obtain the velocity relative to each axis (x, y, z); and integrated again to obtain the position of the device 100 (in linear coordinates, x, y, and z). The angular velocity data from the gyroscope can be integrated to obtain the position of the device 100 (in spherical coordinates). The programming for computing these useful values may be stored in memory 934 and executed by the high-speed processor 932 of the eyewear device 100.

[0064] The eyewear device 100 may optionally include additional peripheral sensors, such as biometric sensors, specialty sensors, or display elements integrated with eyewear device 100. For example, peripheral device elements may include any I/O components including output components, motion components, position components, or any other such elements described herein. For example, the biometric sensors may include components to detect expressions (e.g., hand expressions, facial expressions, vocal expressions, body gestures, or eye tracking), to measure biosignals (e.g., blood pressure, heart rate, body temperature, perspiration, or brain waves), or to identify a person (e.g., identification based on voice, retina, facial characteristics, fingerprints, or electrical biosignals such as electroencephalogram data), and the like.

[0065] The mobile device 890 may be a smartphone, tablet, laptop computer, access point, or any other such device capable of connecting with eyewear device 100 using both a low-power wireless connection 925 and a high-speed wireless connection 937. Mobile device 890 is connected to server system 998 and network 995. The network 995 may include any combination of wired and wireless connections.

[0066] The system, as shown in FIG. 4, includes a computing device, such as mobile device 890, coupled to an eyewear device 100 and to a mobile device 890 over a network. Execution of the programming instructions by the processor 932 configures the eyewear device 100 to cooperate with the mobile device 890. The system may utilize the memory 934 of the eyewear device 100 and/or the memory elements 840A, 840B of the mobile device 890 (FIG. 5). Also, the system may utilize the processor elements 932, 922 of the eyewear device 100 and/or the central processing unit (CPU) 830 of the mobile device 890 (FIG. 5). Furthermore, the system may further utilize the memory and processor elements of the server system 998. In this aspect, the memory and processing functions can be shared or distributed across the eyewear device 100, the mobile device 890, and/or the server system 998.

[0067] FIG. 5 is a high-level functional block diagram of an example mobile device 890. Mobile device 890 includes a flash memory 840A which stores programming to be executed by the CPU 830 to perform all or a subset of the functions described herein. As shown, a computer vision engine 600 may reside on the CPU 830 and accessed for operating one or more applications or modules, one or more of which may be stored in the memory 840A. The mobile device 890 may include an IMU 872 and a loudspeaker 895 for playing sounds.

[0068] The mobile device 890 may include a camera 870 that comprises at least two visible-light cameras (first and second visible-light cameras with overlapping fields of view) or at least one visible-light camera and a depth sensor with substantially overlapping fields of view. Flash memory 840A may further include multiple images or video, which are generated via the camera 870.

[0069] As shown, the mobile device 890 includes an image display 880, a mobile display driver 882 to control the image display 880, and a controller 894. In the example of FIG. 4, the image display 880 includes a user input layer 891 (e.g., a touchscreen) that is layered on top of or otherwise integrated into the screen used by the image display 880.

[0070] Examples of touchscreen-type mobile devices that may be used include (but are not limited to) a smart phone, a personal digital assistant (PDA), a tablet computer, a laptop computer, or other portable device. However, the structure and operation of the touchscreen-type devices is provided by way of example; the subject technology as described herein is not intended to be limited thereto. For purposes of this discussion, FIG. 4 therefore provides a block diagram illustration of the example mobile device 890 with a user interface that includes a touchscreen input layer 891 for receiving input (by touch, multi-touch, or gesture, and the like, by hand, stylus or other tool) and an image display 880 for displaying content.

[0071] As shown in FIG. 4, the mobile device 890 includes at least one digital transceiver (XCVR) 810, shown as WWAN XCVRs, for digital wireless communications via a wide-area wireless mobile communication network. The mobile device 890 also includes additional digital or analog transceivers, such as short range XCVRs 820 for short-range network communication, such as via NFC, VLC, DECT, ZigBee, Bluetooth™, or WiFi. For example, short range XCVRs 820 may take the form of any available two-way wireless local area network (WLAN) transceiver of a type that is compatible with one or more standard protocols of communication implemented in wireless local area networks, such as one of the Wi-Fi standards under IEEE 802.11.

[0072] To generate location coordinates for positioning of the mobile device 890, the mobile device 890 can include a global positioning system (GPS) receiver. Alternatively, or additionally the mobile device 890 can utilize either or both the short range XCVRs 820 and WWAN XCVRs 810 for generating location coordinates for positioning. For example, cellular network, Wi-Fi, or Bluetooth™ based positioning systems can generate very accurate location coordinates, particularly when used in combination. Such location coordinates can be transmitted to the eyewear device over one or more network connections via XCVRs 810, 820.

[0073] The transceivers 810, 820 (i.e., the network communication interface) conforms to one or more of the various digital wireless communication standards utilized by modern mobile networks. Examples of WWAN transceivers 810 include (but are not limited to) transceivers configured to operate in accordance with Code Division Multiple Access (CDMA) and 3rd Generation Partnership Project (3GPP) network technologies including, for example and without limitation, 3GPP type 2 (or 3GPP2) and LTE, at times referred to as “4G.” For example, the transceivers 810, 820 provide two-way wireless communication of information including digitized audio signals, still image and video signals, web page information for display as well as web-related inputs, and various types of mobile message communications to/from the mobile device 890.

[0074] The mobile device 890 further includes a microprocessor that functions as a central processing unit (CPU); shown as CPU 830 in FIG. 4. A processor is a circuit having elements structured and arranged to perform one or more processing functions, typically various data processing functions. Although discrete logic components could be used, the examples utilize components forming a programmable CPU. A microprocessor for example includes one or more integrated circuit (IC) chips incorporating the electronic elements to perform the functions of the CPU. The CPU 830, for example, may be based on any known or available microprocessor architecture, such as a Reduced Instruction Set Computing (RISC) using an ARM architecture, as commonly used today in mobile devices and other portable electronic devices. Of course, other arrangements of processor circuitry may be used to form the CPU 830 or processor hardware in smartphone, laptop computer, and tablet.

[0075] The CPU 830 serves as a programmable host controller for the mobile device 890 by configuring the mobile device 890 to perform various operations, for example, in accordance with instructions or programming executable by CPU 830. For example, such operations may include various general operations of the mobile device, as well as operations related to the programming for applications on the mobile device. Although a processor may be configured by use of hardwired logic, typical processors in mobile devices are general processing circuits configured by execution of programming.

[0076] The mobile device 890 includes a memory or storage system, for storing programming and data. In the example, the memory system may include a flash memory 840A, a random-access memory (RAM) 840B, and other memory components, as needed. The RAM 840B serves as short-term storage for instructions and data being handled by the CPU 830, e.g., as a working data processing memory. The flash memory 840A typically provides longer-term storage.

[0077] Hence, in the example of mobile device 890, the flash memory 840A is used to store programming or instructions for execution by the CPU 830. Depending on the type of device, the mobile device 890 stores and runs a mobile operating system through which specific applications are executed. Examples of mobile operating systems include Google Android, Apple iOS (for iPhone or iPad devices), Windows Mobile, Amazon Fire OS, RIM BlackBerry OS, or the like.

[0078] Computer Vision and Mapping

[0079] FIG. 6 is an illustration of an example map 700, including a marker 730, a note matrix 710, a percussion matrix 770, and a tempo scale 750, suitable for use with the computer vision engine 600 described herein. The map 700 according to some implementations is part of a method of playing a musical composition.

[0080] The marker 730 is an icon or other indicia which provides a known starting point when an instrument such as a camera 870 captures a color image of the map 700. The marker 730 establishes a map coordinate system for all the elements on the map 700. For example, the location of the marker 730 can be used to locate the position of the note matrix 710, and other elements, relative to the map coordinate system. The size and scale of the map coordinate system may vary depending on the size of the map 700; for example, when the map 700 is printed onto a sheet of paper or another surface. In one example implementation, the act of capturing the marker 730 with a camera prompts the electronic device to download the computer vision engine 600.

[0081] The note matrix 710, as shown, includes a plurality of rows and columns. Each row is associated with a note; most often, a note in a musical scale. For example, a fourth row 712A is associated with a fourth note 714A (the note, F, in this example). Notes are different from sounds. Any of a variety of musical instruments can play a particular note, although each instrument will have a unique sound.

[0082] Each column in the note matrix 710 is associated with a beat duration. In music, a beat is the basic unit of time. A series of beats creates a rhythm, which is most often a steady rhythm made up of beats having the same duration. The speed of the beats is known as the tempo. The beat duration for the first column 716A, for example, may be one second.

[0083] The rows and columns of the note matrix 710 define a plurality of fields 720. For example, the note matrix 710 in FIG. 6 includes eight rows and eight columns, defining sixty-four fields. Each field in the note matrix 710 is characterized by a set of field coordinates relative to the map coordinate system (which is based on the marker 730). When a map 700 is printed on a sheet of paper and laid flat, or onto another flat surface, the map coordinate system may be two-dimensional.

[0084] The computer vision engine 600 in some implementations includes a mapping module 601 which may accomplish the steps of recognizing the marker 730, setting the map coordinate system, and then identifying the set of field coordinates associated with each field 720 in the note matrix 710.

[0085] A color image captured by a digital camera is used to detect the positions, colors, and other attributes of each field 720 and other elements on the map 700. The color image may be shown on the display screen of a mobile device 890, as described herein. The location of specific points in the color image, therefore, may be described using a two-dimensional display coordinate system that is associated with the display screen of the mobile device 890. The mapping module 601 in some implementations converts the set of field coordinates for each field to a pair of display coordinates. In this aspect, the coordinates for each field on paper are converted into coordinates for each field on the display.

[0086] Tokens 760 are placed on the note matrix 710 in order to create a musical composition. FIG. 7 is an illustration of a set of example tokens 760 which are ready to be cut and placed on a note matrix 710. In the example, a first token 760A is associated with a first sound sample for a keyboard instrument, such as a plano. A second token 760B is associated with a second sound sample for a brass instrument, such as a cornet. A third token 760C is associated with a third sound sample for a string instrument, such as a viola. Although illustrated as squares, the tokens 760 may be any size and shape suitable for a particular map 700. The tokens 760 are illustrated as shaded squares in FIG. 7; however, instead of shading, each type of token 760 has a particular token color. For example, the first token 760A may be red in color, such that a token color of red is associated with the first sound sample for a keyboard instrument.

[0087] The computer vision engine 600 in some implementations includes a color detection module 602 which may accomplish the step of detecting a token color value for each field 720 in the note matrix 710. The color detection module 602 analyzes the color image of the map 700 that was captured by the camera. The color image captured by a digital camera includes raw data about the color at each location or pixel. Each color may be expressed as a set of RGB values, also known as an RGB triplet. A color in the RGB color model is described by indicating how much of each of red (R), green (G), and blue (B) color is present. For a digital image, 8 bits per channel, the amount of each color is expressed as an integer between zero and 255. The color white, for example, is expressed as RGB (255, 255, 255); a mixture of all three colors. The color red is expressed as RGB (255, 0, 0). The numerical RGB values are useful when comparing colors based on their relative saturation and intensity.

[0088] The token color value for each field 720 determines the musical instrument sound to be played, the row where a token 760 is placed determines the note 712 to be played, and the column 716 determines the beat or time at which the sound is to be played.

[0089] For example, in the note matrix 710 shown in FIG. 6, a first token 760A is placed in the fourth row 712A and in the first column 716A. The first token 760A, as shown, is not perfectly centered in the field; in other words, the token may not be perfectly aligned with the pair of display coordinates for the field. The color detection module 602 detects the token color value that is near the display coordinates. According to the example note matrix 710, for the first beat of music (associated with the first column 716A), the presence of the first token 760A is detected in the fourth row 712A (associated with the fourth note 714A (note F)), and the first token color value of the first token 760A is detected as red (RGB 255, 0, 0; which is associated with the sounds of a keyboard instrument). During playback, as described herein, a sound sample for a keyboard instrument plays the note F on the first beat; and so on, for each beat (column) in sequence until completed.

[0090] In use, any number of tokens 760 of various colors may be placed anywhere on the note matrix 710. To record the position and color of each token, the computer vision engine 600 stores in memory a global state map, which includes the token color value (as detected by the color detection module 602) and the pair of display coordinates for each field in the note matrix 710. In this aspect, the global state map acts as a guide during playback (by the music playback module 603).

[0091] Each example token 760, as shown in FIG. 7, is associated with a sound sample associated with a particular musical instrument. The computer vision engine 600 in some implementations includes the step of storing in the memory a plurality of preset token color values, where each one is associated with a preset sound sample. The values may be stored in a table or database, for example. The first token 760A may be associated with a first preset token color value of pure red (RGB 255, 0, 0), with a first sound sample from a keyboard instrument. In use, the first sound sample will include, of course, the sound of each note in a musical scale (because a first token 760A may be placed in any row 712 of the note matrix 710).

[0092] The sound samples for each instrument, including a variety of notes, may be obtained from any of a variety of available sound libraries. The computer vision engine 600 in some examples may be configured to record user-created sounds, such as the user's singing voice, other vocal sounds, and percussive sounds such as hand claps and finger snaps.

[0093] Printing: The token color value of a token 760 printed in color on a paper usually does not have the same RGB value as the preset token color value. For example, the first preset token color value of pure red (RGB 255, 0, 0) when printed on paper may have different RGB values. Depending on the printer, ink colors, paper type, and a host of other variables, the actual token color value of a first token 760A printed on paper may not be pure red. The printed first token 760A may appear red on paper, but in the digital color image it may include other colors: for example, the red may be (RGB 231, 111, 96). The color detection module 602 in some implementations performs the step of calculating a difference between the token color value on paper (RGB 231, 111, 96) and one or more of the plurality of preset token color values (which includes pure red, RGB 255, 0, 0). The calculated difference is used to select the preset token color value that is closest to the token color value as it appears on paper.

[0094] The background color value also varies depending on the printer and it is usually not the same as pure white (RGB 255, 255, 255). The color detection module 602 in some implementations performs the step of detecting the background color value associated with an unmarked area 739 of the map 700 as printed in color on a sheet of paper or other surface. The unmarked area in some implementations is part of the marker 730. The color detection module 620 then calculates a ratio between the background color value on paper and the preset background color value (typically, pure white RGB 255, 255, 255).

[0095] For many printers, this ratio can be used to correct or otherwise adjust some or all of the other color values on the map 700. The color detection module 620 multiplies each token color value by the ratio to obtain a modified token color value. Using the modified values, the color detection module 620 calculates a variance between each modified token color value and one or more of the plurality of preset token color values. The variance is used to select the preset token color value that is closest to the token color value as it appears on paper.

[0096] Referring again to FIG. 4, the map 700 may also include a percussion matrix 770. The columns of the percussion matrix 770 are aligned with the columns of the note matrix 710, as shown. Each rhythm row 772 is associated with a percussion sound. For example, a second row 772B is associated with a hand-clap sound. The rhythm rows 772 do not refer to notes because percussion sounds are not associated with notes on a scale. The rows and columns define a plurality of rhythm fields. The mapping module 601 as described herein identifies the rhythm field coordinates associated with each rhythm field.

[0097] The color detection module 620 in some implementations detects whether a percussion token 778 is present or not at each rhythm field location. In this aspect, the rhythm attribute value for each rhythm field is a binary variable; either one or zero. The percussion token 778 may be a particular color or no color. According to the example percussion matrix 770 in FIG. 6, for the first beat of music (associated with the first column 716A), the presence of the percussion token 778 is detected in the second rhythm row 772B (associated with a hand-clap sound). During playback, as described herein, a percussion sound sample for a hand clap is played on the first beat—at the same time a sound sample for a keyboard instrument plays the note F on the first beat (based on the note matrix 710). In this aspect, the playing of percussion sounds is substantially correlated in time with said playing of the sound samples for instruments.

[0098] Referring again to FIG. 4, the map 700 may also include a pointer 752 located along a tempo scale 750 that extends lengthwise from a minimum speed to a maximum speed. The mapping module 601 as described herein may be used to identify the pointer coordinates relative to the tempo scale 750. The music playback module 603 may adjust the beat duration (associated with each column 716) according to the pointer coordinates, such that the relative location of the pointer 752 determines the playback tempo.

[0099] In some implementations, the music playback module 603 may be set to play the music in each column 716, in sequence, through and including the last column. The playing may be repeated in a continuing loop. The music playback module 603 uses the global state map to determine the selection and sequence of notes and sounds to be played. The global state map in some implementations is persistent; that is, it remains set unless and until the map 700 is changed. In this aspect, the mobile device 890 may be directed away from the map 700, so that the map 700 is not within the field of view of the camera 870; nevertheless, the stored global state map will persist and the playback will continue, as stored.

[0100] When changes are made to the map 700, the computer vision engine 600 is configured to periodically capture a subsequent color image (of the new map), store in the memory an updated global state map, and then play the music in accordance with the updated global state map.

[0101] In a related aspect, the computer vision engine 600 may include a hand detection algorithm that will pause the step of storing an updated global state map while and for as long as the algorithm detects a hand in any subsequent color image. In other words, if and when a hand is detected in a subsequent color image (of the new map), the computer vision engine 600 will not attempt to detect a color value for the hand or otherwise build an updated global state map.

[0102] In some implementations, the map 700 is placed in the field of view of a digital camera 870 of a mobile device 890. Accordingly, the color image of the map 700 is shown (continuously, in the usual case) on the display screen of the mobile device 890. The mobile device 890 may be mounted on a tripod or otherwise held in position relative to the map 700 during use. The music playback module 603 in some implementations is configured to project a virtual object on the display screen according to the global state map. The virtual object may include any of a variety of graphical elements, colors, or other indicia. For example, the virtual object may be a glowing square or other highlight that appears near the field of the note or sound when it is played.

[0103] In a related aspect, the map 700 may be located in the field of view of one or more lenses 180A, 180B of a wearable device, such as an eyewear device 100. The eyewear device 100 may include a projector and a semi-transparent display. The music playback module 603 in some implementations is configured to project a virtual object onto the semi-transparent display, using the global state map and the coordinates associated with the semi-transparent display to place the virtual object in a desired location. In this aspect, the computer vision engine 600 is configured to overlay the virtual object relative to a physical environment, as part of an augmented reality.

[0104] A wearable device, such as eyewear 100, may include a number of loudspeakers or other assemblies that provide spatial audio capability. In use, particular sounds may seem to originate from one or more locations in space relative to the wearer. Because the position of the map 700 relative to the eyewear 100 is known, the sounds of the instruments during playback may be spatialized.

[0105] Any of the functionality described herein for the eyewear device 100, the mobile device 890, and the server system 998 can be embodied in one or more computer software applications or sets of programming instructions, as described herein. According to some examples, “function,” “functions,” “application,” “applications,” “instruction,” “instructions,” or “programming” are program(s) that execute functions defined in the programs. Various programming languages can be employed to create one or more of the applications, structured in a variety of manners, such as object-oriented programming languages (e.g., Objective-C, Java, or C++) or procedural programming languages (e.g., C or assembly language). In a specific example, a third-party application (e.g., an application developed using the ANDROID™ or IOS™ software development kit (SDK) by an entity other than the vendor of the particular platform) may include mobile software running on a mobile operating system such as IOS™, ANDROID™, WINDOWS® Phone, or other mobile operating systems. In this example, the third-party application can invoke API calls provided by the operating system to facilitate functionality described herein.

[0106] Hence, a machine-readable medium may take many forms of tangible storage medium. Non-volatile storage media include, for example, optical or magnetic disks, such as any of the storage devices in any computer devices or the like, such as may be used to implement the client device, media gateway, transcoder, etc. shown in the drawings. Volatile storage media include dynamic memory, such as main memory of such a computer platform. Tangible transmission media include coaxial cables; copper wire and fiber optics, including the wires that comprise a bus within a computer system. Carrier-wave transmission media may take the form of electric or electromagnetic signals, or acoustic or light waves such as those generated during radio frequency (RF) and infrared (IR) data communications. Common forms of computer-readable media therefore include for example: a floppy disk, a flexible disk, hard disk, magnetic tape, any other magnetic medium, a CD-ROM, DVD or DVD-ROM, any other optical medium, punch cards paper tape, any other physical storage medium with patterns of holes, a RAM, a PROM and EPROM, a FLASH-EPROM, any other memory chip or cartridge, a carrier wave transporting data or instructions, cables or links transporting such a carrier wave, or any other medium from which a computer may read programming code and/or data. Many of these forms of computer readable media may be involved in carrying one or more sequences of one or more instructions to a processor for execution.

[0107] Except as stated immediately above, nothing that has been stated or illustrated is intended or should be interpreted to cause a dedication of any component, step, feature, object, benefit, advantage, or equivalent to the public, regardless of whether it is or is not recited in the claims.

[0108] It will be understood that the terms and expressions used herein have the ordinary meaning as is accorded to such terms and expressions with respect to their corresponding respective areas of inquiry and study except where specific meanings have otherwise been set forth herein. Relational terms such as first and second and the like may be used solely to distinguish one entity or action from another without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms “comprises,” “comprising,” “includes,” “including,” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises or includes a list of elements or steps does not include only those elements or steps but may include other elements or steps not expressly listed or inherent to such process, method, article, or apparatus. An element preceded by “a” or “an” does not, without further constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0109] Unless otherwise stated, any and all measurements, values, ratings, positions, magnitudes, sizes, and other specifications that are set forth in this specification, including in the claims that follow, are approximate, not exact. Such amounts are intended to have a reasonable range that is consistent with the functions to which they relate and with what is customary in the art to which they pertain. For example, unless expressly stated otherwise, a parameter value or the like may vary by as much as plus-or-minus ten percent relative to the stated value.

[0110] In addition, in the foregoing Detailed Description, it can be seen that various features are grouped together in various examples for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed examples require more features than are expressly recited in each claim. Rather, as the following claims reflect, the subject matter to be protected lies in less than all features of any single disclosed example. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separately claimed subject matter.

[0111] While the foregoing has described what are considered to be the best mode and other examples, it is understood that various modifications may be made therein and that the subject matter disclosed herein may be implemented in various forms and examples, and that they may be applied in numerous applications, only some of which have been described herein. It is intended by the following claims to claim any and all modifications and variations that fall within the true scope of the present concepts.