Patent Publication Number: US-2022224744-A1

Title: Codec selection for end-to-end communication without intermediate transcoding

Description:
This application is a continuation of U.S. patent application Ser. No. 16/940,332, filed Jul. 27, 2020, now U.S. Pat. No. 11,209,512, which is a continuation of U.S. patent application Ser. No. 15/832,308, filed Dec. 5, 2017, now U.S. Pat. No. 10,728,303, both of which are herein incorporated by reference in their entirety. 
     The present disclosure relates generally to digital media distribution, and relates more particularly to devices, non-transitory computer-readable media, and methods for improving media quality at the network edge by encoding the media into a digital stream that is carried, end-to-end, to a peer edge device. 
    
    
     BACKGROUND 
     Mobile device users often pair other wireless electronic devices, such as Bluetooth headsets, speakers, cameras, fitness trackers, and wearable smart devices, with their mobile devices. For instance, when placing a call to a receiver&#39;s mobile phone, call data may be sent in a digital data stream from the sender&#39;s paired headset to his mobile phone, reduced to baseband audio and/or video, and then re-encoded for transmission over a cellular packet network. Subsequently, if the sender&#39;s and receiver&#39;s networks and/or mobile phone(s) are not compatible, then the digital data stream is transcoded (i.e., converted from one file format to another), sometimes via baseband, and then the transcoded digital data stream is forwarded to the receiver&#39;s mobile phone. The receiver&#39;s mobile phone may then extract the call data from the digital stream and encode the call data for use across the receiver&#39;s paired devices. 
     SUMMARY 
     In one example, the present disclosure describes a device, computer-readable medium, and method for improving media quality at the network edge by encoding the media into a digital stream that is carried, end-to-end, to a peer edge device. For instance, in one example, a method includes initiating, by a first computing device, a connection to a second computing device, selecting, by the first computing device, a codec for encoding data into a data stream, wherein the codec is selected such that the data stream can be decoded by the second computing device without being transcoded by an intermediary, encoding, by the first computing device, the data into the data stream using the codec, and sending, by the first computing device, the data stream to the second computing device. 
     In another example, a computer-readable medium stores instructions which, when executed by the processor, cause the processor to perform operations. The operations include initiating, by a first computing device, a connection to a second computing device, selecting, by the first computing device, a codec for encoding data into a data stream, wherein the codec is selected such that the data stream can be decoded by the second computing device without being transcoded by an intermediary, encoding, by the first computing device, the data into the data stream using the codec, and sending, by the first computing device, the data stream to the second computing device. 
     In another example, a method for improving media quality at the network includes initiating, by a first computing device, a connection to a second computing device, selecting, by the first computing device, a codec for encoding data into a data stream, wherein the codec is selected such that the data stream can be decoded by the second computing device without being transcoded by a lossy transcoder, encoding, by the first computing device, the data into the data stream using the codec, and sending, by the first computing device, the data stream to the second computing device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The teachings of the present disclosure can be readily understood by considering the following detailed description in conjunction with the accompanying drawings, in which: 
         FIG. 1  illustrates an example network, related to the present disclosure; 
         FIG. 2  illustrates a high-level block diagram of an example computing device specifically programmed to support end-to-end encoding of media in a digital stream; and 
         FIG. 3  illustrates a flowchart of an example method for encoding the media into a digital stream that is carried, end-to-end, to a peer edge device. 
     
    
    
     To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. 
     DETAILED DESCRIPTION 
     In one example, the present disclosure provides a means for improving media quality at the network edge by encoding the media into a digital stream that is carried, end-to-end, to a peer edge device. As discussed above, mobile device users often pair other wireless electronic devices, such as Bluetooth headsets, speakers, cameras, fitness trackers, and wearable smart devices, with their mobile devices in order to consume data. This often necessitates the transcoding—sometimes multiple times—of the data. For instance, even a simple mobile-to-mobile call may require transcoding in the event that the mobile devices use different codecs (e.g., universal mobile telecommunications system (UMTS) to voice over long-term evolution (VoLTE), general packet radio service to VoLTE, etc.). Calls involving additional or different communication devices may require even further transcoding (e.g., satellite phone to UMTS or VoLTE, additional transcoding between mobile devices and paired headsets, between a public switched telephone network (PSTN) and a speaker phone, or between the Internet and a computer phone). Transcoding introduces delay in addition to the normal and expected packet forwarding delays and can also cause a loss of fidelity in the data itself. This results in unsatisfactory customer experience. 
     Examples of the present disclosure provide for end-to-end encoding and decoding of media at the sending and receiving devices. In one example, the real-world media (e.g., image, video, or audio) is encoded into a digital data stream that is carried, end-to-end, to the receiving edge device without being brought back to baseband, re-encoded into another format, and decoded along the way. Thus, in some examples, encoding and decoding of the digital data stream happens only at the network edge or in the sending and receiving devices. A codec for encoding the digital data stream may be mutually selected by the sending and receiving devices in advance of the exchange of the media. For instance, a codec may be selected at connection setup or may be selected from pre-established profiles that define supported codecs for the sending and receiving devices (and potentially other intermediate devices in the path from the sending device to the receiving device). This eliminates or reduces the need for transcoding (i.e., either no transcoder is used, or a lossless transcoder is used), which in turn will minimize the latency of the resulting connection between the sending and receiving devices as well as minimize the loss of fidelity in the media being exchanged. Thus, the customer experience is improved. 
     Examples of the present disclosure may improve customer experience in a number of scenarios, including send-and-store and store-and-send communications, point-to-point and point-to-multipoint communications (e.g., push-to-talk communications between multiple parties, n-way conference calls, and the like), and half duplex and full duplex communications and combinations thereof. 
     To better understand the present disclosure,  FIG. 1  illustrates an example network  100 , related to the present disclosure. As shown in  FIG. 1 , the network  100  may comprise a content distribution network (e.g., data network) that connects mobile devices  157 A,  157 B,  167 A and  167 B, and devices such as router  165 , personal computer (PC)  166 , tablet computer  162 , home phone  164 , and paired accessories such as Bluetooth headsets  163 A and  163 B and so forth, with one another and with various other devices via a core network  110 , a wireless access network  150  (e.g., a cellular network), an access network  120 , other networks  140  (including additional servers  149 ) and/or the Internet  145 . Mobile devices  157 A,  157 B,  167 A and  167 B, and devices such as personal computer (PC)  166 , tablet computer  162 , home phone  164 , and paired accessories such as Bluetooth headsets  163 A and  163 B may also be referred to herein as “customer devices” or “user endpoint devices.” 
     In one example, wireless access network  150  comprises a radio access network implementing such technologies as: global system for mobile communication (GSM), e.g., a base station subsystem (BSS), or IS-95, a universal mobile telecommunications system (UMTS) network employing wideband code division multiple access (WCDMA), or a CDMA 3000  network, among others. In other words, wireless access network  150  may comprise an access network in accordance with any “second generation” (2G), “third generation” (3G), “fourth generation” (4G), Long Term Evolution (LTE) or any other yet to be developed future wireless/cellular network technology including “fifth generation” (5G) and further generations. While the present disclosure is not limited to any particular type of wireless access network, in the illustrative example, wireless access network  150  is shown as a UMTS terrestrial radio access network (UTRAN) subsystem. Thus, elements  152  and  153  may each comprise a Node B or evolved Node B (eNodeB). 
     In one example, each of mobile devices  157 A,  157 B,  167 A, and  167 B may comprise any subscriber/customer endpoint device configured for wireless communication such as a laptop computer, a Wi-Fi device, a Personal Digital Assistant (PDA), a mobile phone, a smartphone, an email device, a computing tablet, a messaging device, a global positioning system (GPS), a portable gaming device, a wearable smart device (e.g., a smart watch or a fitness tracker), a satellite radio receiver or satellite television receiver, or any other device having a user interface that is capable of receiving bandwidth from the network  100  in the form of streaming data. In one example, any one or more of mobile devices  157 A,  157 B,  167 A, and  167 B may have both cellular and non-cellular access capabilities and may further have wired communication and networking capabilities. Any one or more of mobile devices  157 A,  157 B,  167 A, and  167 B may have installed thereon a digital content distribution application that allows the user of the mobile device to access digital multimedia content such as videos, images, audio, web sites, and the like. 
     As illustrated in  FIG. 1 , network  100  includes a core network  110 . In one example, core network  110  may combine core network components of a cellular network with components of a triple play or n-play service network; where triple play services include telephone services, Internet services and television services to subscribers, and n-play services may include any one or more of the triple play services plus additional services (e.g., such as security monitoring, health monitoring, geo fencing, and the like). For example, core network  110  may functionally comprise a fixed mobile convergence (FMC) network, e.g., an IP Multimedia Subsystem (IMS) network. In addition, core network  110  may functionally comprise a telephony network, e.g., an Internet Protocol/Multi-Protocol Label Switching (IP/MPLS) backbone network utilizing Session Initiation Protocol (SIP) for circuit-switched and Voice over Internet Protocol (VoIP) telephony services. Core network  110  may also further comprise a broadcast television network, e.g., a traditional cable provider network or an Internet Protocol Television (IPTV) network, as well as an Internet Service Provider (ISP) network. The network elements  111 A- 111 D may serve as gateway servers or edge routers to interconnect the core network  110  with other networks  140 , Internet  145 , wireless access network  150 , access network  120 , and so forth. In one example, the network elements  111 A- 111 D comprise repositories of codecs that can be selected by and downloaded to the mobile devices  157 A,  157 B,  167 A and  167 B, and devices such as personal computer (PC)  166 , tablet computer  162 , home phone  164 . As shown in  FIG. 1 , core network  110  may also include a plurality of television (TV) servers  112 , a plurality of content servers  113 , a plurality of application servers  114 , an advertising server (AS)  117 , and a repository of connection parameters  115 . For ease of illustration, various additional elements of core network  110  are omitted from  FIG. 1 . 
     With respect to television service provider functions, core network  110  may include one or more third party television content (TV) servers  112  for the delivery of television content. In this regard, television servers  112  may interact with content servers  113  and advertising server  117  to select which video programs, or other content and advertisements to provide to the home network  160 , to the mobile devices  157 A,  157 B,  167 A, and  167 B, and to other downstream viewing locations. 
     In one example, content servers  113  may store scheduled television content for a number of third party television content providers, video-on-demand programming, local programming content, and so forth. For example, third party television content providers may upload various contents to the core network to be distributed to various subscribers. Alternatively, or in addition, third party television content providers may stream various contents to the core network for distribution to various subscribers, e.g., for live content, such as news programming, sporting events, and the like. In one example, advertising server  117  stores a number of advertisements that can be selected for presentation to viewers, e.g., in the home network  160 , via the mobile devices  157 A,  157 B,  167 A, and  167 B, and at other downstream viewing locations. For example, advertisers may upload various advertising content to the core network  110  to be distributed to various viewers. 
     The application server(s)  114  may include lossless transcoders for transcoding data. Within the context of the present disclosure, a “lossless” transcoder is understood to refer to a transcoder that is nearly lossless, or that is lossy but has minimal or limited impact on customer-perceived data quality. In some examples, rather than bypassing a transcoder completely, data being exchanged may be transcoded by a lossless transcoder (but bypass any lossy transcoders). 
     The repository of connection parameters  115  may store parameters relating to connections between mobile devices  157 A,  157 B,  167 A and  167 B, and devices such as personal computer (PC)  166 , tablet computer  162 , home phone  164 . These parameters may include, for example, preferred and/or supported codecs associated with mobile devices  157 A,  157 B,  167 A and  167 B, and devices such as personal computer (PC)  166 , tablet computer  162 , home phone  164 . As discussed in greater detail below, the repository of connection parameters  115  may be consulted during the setup of a connection between devices in order to support end-to-end encoding of exchanged data. 
     In one example, the access network  120  may comprise a Digital Subscriber Line (DSL) network, a Local Area Network (LAN), a cellular or wireless access network, a 3 rd  party network, and the like. In this regard, access network  120  may include a node  122 , e.g., a mini-fiber node (MFN), a video-ready access device (VRAD) or the like. However, in another example node  122  may be omitted, e.g., for fiber-to-the-premises (FTTP) installations. Access network  120  may also transmit and receive communications between home network  160  and core network  110  relating to communications with web servers via the Internet  145  and/or other networks  140 , and so forth. 
     In one example, home network  160  may include a router  165 , which receives data/communications associated with different types of media, e.g., television, phone, and Internet, and separates these communications for the appropriate devices. The data/communications may be received via access network  120 , for instance. In one example, Internet communications are sent to and received from router  165 , which may be capable of both wired and/or wireless communication. In turn, router  165  receives data from and sends data to the appropriate devices, e.g., tablet  162 , personal computer (PC)  166 , mobile devices  167 A, and  167 B, and so forth. Each of these devices may be configured to support media content of particular file formats. In one example, router  165  may further communicate with other devices in the home network  160 , such as set top boxes, smart televisions, or the like (not shown). In one example, router  165  may comprise a wired Ethernet router and/or an Institute for Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi) router, and may communicate with respective devices in home network  160  via wired and/or wireless connections. 
     It should be noted that as used herein, the terms “configure” and “reconfigure” may refer to programming or loading a computing device with computer-readable/computer-executable instructions, code, and/or programs, e.g., in a memory, which when executed by a processor of the computing device, may cause the computing device to perform various functions. Such terms may also encompass providing variables, data values, tables, objects, or other data structures or the like which may cause a computer device executing computer-readable instructions, code, and/or programs to function differently depending upon the values of the variables or other data structures that are provided. For example, mobile device  167 A and/or mobile device  167 B may be equipped with an application to send control signals to a paired device, such as a headset  163 A, via an infrared transmitter or transceiver, a transceiver for IEEE 802.11 based communications (e.g., “Wi-Fi”), IEEE 802.15 based communications (e.g., “Bluetooth”, “ZigBee”, etc.), and so forth, where the paired device is similarly equipped to receive such a signal. 
     Those skilled in the art will realize that the network  100  may be implemented in a different form than that which is illustrated in  FIG. 1 , or may be expanded by including additional endpoint devices, access networks, network elements, application servers, etc. without altering the scope of the present disclosure. For example, core network  110  is not limited to an IMS network. Wireless access network  150  is not limited to a UMTS/UTRAN configuration. Similarly, the present disclosure is not limited to an IP/MPLS network for VoIP telephony services, or any particular type of broadcast television network for providing television services, and so forth. 
       FIG. 2  illustrates a high-level block diagram of an example computing device  200  specifically programmed to support end-to-end encoding of media in a digital stream. For example, any of the mobile devices  157 A,  157 B,  167 A and  167 B, and devices such as personal computer (PC)  166 , tablet computer  162 , home phone  164  illustrated in  FIG. 1  may be configured as illustrated in  FIG. 2 . Alternatively, certain functions of the computing device  200  may be supported across one or more devices in the network  100  of  FIG. 1 , such as a repository of codecs (e.g., as embodied in network elements  111 A- 111 D) and/or the repository of connection parameters  115 . 
     As depicted in  FIG. 2 , the system  200  comprises a hardware processor element  202 , a memory  204 , a module  205  for encoding data into a digital stream, and various input/output (I/O) devices  206 . 
     The hardware processor  202  may comprise, for example, a microprocessor, a central processing unit (CPU), or the like. In one example, the processor  202  may include an encoder/decoder  212  that encodes and decodes data in conjunction with instructions stored by the module  205  for encoding data into a digital stream and codecs stored in the memory  204 . 
     The memory  204  may comprise, for example, volatile and/or non-volatile memory, such as random access memory (RAM), read only memory (ROM), static RAM (SRAM) memory, Flash memory, a disk drive, an optical drive, a magnetic drive, and/or a Universal Serial Bus (USB) drive. In one example, the memory  204  may store a set of contacts  208  and a set of codecs  210 . The set of contacts  208  may comprise, for instance, profiles for one or more other devices with which the computing device  200  communicates or has communicated. Each profile may be associated with a different device and may include, for that device, a nickname (e.g., “Mom&#39;s cell phone,” “James&#39;s tablet,” etc.), contact information (e.g., mobile phone number, IP address, MAC address, or the like), connection parameters (including, e.g., a list of supported or preferred codecs, connection diagnostics ,network(s) likely to be used, accessories or peripherals likely to be used, or other parameters), and/or other information. The set of codecs  210  may comprise one or more permanently and/or temporarily stored codecs that are accessible to the encoder/decoder  212  for encoding and decoding data. 
     The module  205  for encoding data into a digital stream may include circuitry and/or logic for performing special purpose functions described herein relating to encoding data into a digital stream for end-to-end transmission. The input/output devices  206  may include, for example, a camera, a video camera, storage devices (including but not limited to, a tape drive, a floppy drive, a hard disk drive or a compact disk drive), a receiver, a transmitter, a display, an output port, a speaker, a microphone, or a user input device (such as a keyboard, a keypad, a mouse, and the like). 
     Although only one processor element is shown, it should be noted that the general-purpose computer may employ a plurality of processor elements. Furthermore, although only one general-purpose computer is shown in the Figure, if the method(s) as discussed below is implemented in a distributed or parallel manner fora particular illustrative example, i.e., the steps of the below method(s) or the entire method(s) are implemented across multiple or parallel general-purpose computers, then the general-purpose computer of this Figure is intended to represent each of those multiple general-purpose computers. Furthermore, one or more hardware processors can be utilized in supporting a virtualized or shared computing environment. The virtualized computing environment may support one or more virtual machines representing computers, servers, or other computing devices. In such virtualized virtual machines, hardware components such as hardware processors and computer-readable storage devices may be virtualized or logically represented. 
     It should be noted that the present disclosure can be implemented in software and/or in a combination of software and hardware, e.g., using application specific integrated circuits (ASIC), a programmable logic array (PLA), including a field-programmable gate array (FPGA), or a state machine deployed on a hardware device, a general purpose computer or any other hardware equivalents, e.g., computer readable instructions pertaining to the method(s) discussed above can be used to configure a hardware processor to perform the steps, functions and/or operations of the below disclosed method(s). In one example, instructions and data for the present module or process  205  for encoding data into a digital stream (e.g., a software program comprising computer-executable instructions) can be loaded into memory  204  and executed by hardware processor element  202  to implement the steps, functions or operations as discussed below in connection with the example method  300 . Furthermore, when a hardware processor executes instructions to perform “operations,” this could include the hardware processor performing the operations directly and/or facilitating, directing, or cooperating with another hardware device or component (e.g., a co-processor and the like) to perform the operations. 
     The processor executing the computer readable or software instructions relating to the below described method(s) can be perceived as a programmed processor or a specialized processor. As such, the present module  205  for encoding data into a digital stream (including associated data structures) of the present disclosure can be stored on a tangible or physical (broadly non-transitory) computer-readable storage device or medium, e.g., volatile memory, non-volatile memory, ROM memory, RAM memory, magnetic or optical drive, device or diskette and the like. More specifically, the computer-readable storage device may comprise any physical devices that provide the ability to store information such as data and/or instructions to be accessed by a processor or a computing device such as a computer or an application server. 
     Thus, the codecs for end-to-end encoding of data may be stored locally in the customer devices. Two customer devices may negotiate, e.g., during connection setup, a preferred codec to be used for the connection. If one or both of the customer devices does not have the preferred codec stored locally, the preferred codec may be downloaded from a repository in the network (e.g., from one of network elements  111 A- 111 D of  FIG. 1 ). This eliminates or minimizes the need for transcoding of the data on the intermediary from the sender to the receiver, thereby minimizing delay and fidelity loss and improving the customer experience. It also minimizes the need for dedicated transcoding infrastructure in the network. Storage of preferred codecs and connection parameters associated with contacts may also accelerate the connection process when two customer devices are setting up a connection (e.g., by allowing the connection to default to the preferred codecs and connection parameters), which further improves the customer experience. Moreover, by sharing a set of codecs among a pool of customers, the operator of the network may save on codec licenses. 
     The repository of connection parameters  115  illustrated in  FIG. 1  may be used in place of or in addition to locally stored profile data to accelerate connections. For instance, as discussed above, a computing device may “remember” the preferred connection parameters and codecs of the other devices with which it has communicated. In one example, however, the repository of connection parameters  115  may pre-emptively load the computing device with the preferred connection parameters and/or codecs or computing devices with which it has not communicated. For instance, if a first computing device often communicates with a set of computing devices that also frequently communicate with a second computing device, the preferred connection parameters and codecs may be pre-emptively loaded to the first computing device in anticipation of a need to communicate with the second computing device (i.e., based on the first computing device and the second computing device having communicated with a common set of contacts/other computing devices). In this case, customers may opt in to share public and/or private information, such as information contained in social media profiles, device address books, and the like. 
     To further aid in understanding the present disclosure,  FIG. 3  illustrates a flowchart of an example method  300  for encoding the media into a digital stream that is carried, end-to-end, to a peer edge device. In one example, the method  300  may be performed by a customer computing device, such as the computing device  200  of  FIG. 2 . However, in other examples, the method  300  may be performed by another device or devices (e.g., one or more application servers  114  or other device(s)). As such, any references in the discussion of the method  300  to components of  FIG. 1 and/or 2  are not intended to limit the means by which the method  300  may be performed. 
     The method  300  begins in step  302 . In step  304 , a connection is initiated between a first computing device and a second computing device (e.g., either of the first computing device or the second computing device may initiate the connection or be the sender). Either or both of the first computing device and the second computing device may comprise, for instance, a mobile phone, a landline phone, a satellite phone, a speaker phone, a computer phone, a tablet computer, a laptop computer, a personal computer, or another type of communication device. Furthermore, one or both of the first computing device and the second computing device may be paired with another wireless device, such as a Bluetooth headset or speaker, a wearable smart device, a fitness tracker, or the like. The first computing device and the second computing device may connect to a core network via the same access network, or via different access networks. For instance, the first computing device may be mobile device  167 A of  FIG. 1 , while the second computing device is mobile device  157 A of  FIG. 1 . 
     In step  306 , a codec for encoding exchanged data via the connection is selected by the first computing device and the second computing device, e.g., as part of the connection setup process. In one example, the computing device initiating the connection (e.g., the sender) may unilaterally select a codec, for example based on a codec that is associated with a profile for the other computing device (e.g., the receiver). For instance, if the first computing device is initiating the connection, the first computing device may select a codec that it used in conjunction with a previous connection to the second computing device (e.g., as indicated in a locally stored profile for the second computing device), or that is associated with the second computing device in a remotely stored repository of connection parameters (e.g., repository of connection parameters  115  of  FIG. 1 ). The second computing device could then opt in to the use of the selected codec as part of the connection setup process. In another example, the selected codec may be mutually negotiated by the first and second computing devices as part of the connection setup process. In another example, the codec may be automatically selected based on an analysis of the profiles of the first and second computing devices (e.g., the codec best-suited for the profiles and/or the aggregate resources across the path between the first and second computing devices may be automatically selected). In one or example, selection of the codec may involve one or both of the first and second computing devices downloading the selected codec from the network (e.g., from one of the network elements  111 A- 111 D of  FIG. 1 ). Additional connection parameters may be selected or negotiated in a similar manner in step  306 . 
     In step  308 , the connection between the first computing device and the second computing device is established, based on the codec and connection parameters selected in step  306 . 
     In step  310 , data is exchanged over the connection between the first computing device and the second computing device, in accordance with the selected codec and connection parameters. In one example, the exchange of data is performed without performing any transcoding at an intermediary between the first computing device and the second computing device. For instance, the exchange of data in step  310  may involve the first computing device encoding data using the codec selected in step  306  into a digital data stream and sending the digital data stream to the second computing device. The exchange of data in step  310  may further involve the second computing device decoding the digital data stream using the codec selected in step  306  to retrieve the data. In another example, a lossless transcoder performs some amount of transcoding in between the sending of the data and the receipt of the digital data stream, but the digital data stream is exchanged without assistance or transcoding by a lossy transcoder. That is, the lossless transcoder may transcode the digital data stream after it is send by the sender, but before it is received by the receiver. 
     In step  312 , it is determined whether the connection should be terminated. If it is determined in step  312  that the connection should not be terminated, then the method  300  returns to step  310 , and the first and second computing devices continue to exchange data using the selected codec. If, however, it is determined in step  312  that the connection should be terminated, then the connection is terminated in step  314 . The method  300  then ends in step  316 . 
     Although not expressly specified above, one or more steps of the method  200  may include a storing, displaying and/or outputting step as required for a particular application. In other words, any data, records, fields, and/or intermediate results discussed in the method can be stored, displayed and/or outputted to another device as required for a particular application. Furthermore, operations, steps, or blocks in  FIG. 3  that recite a determining operation or involve a decision do not necessarily require that both branches of the determining operation be practiced. In other words, one of the branches of the determining operation can be deemed as an optional step. Furthermore, operations, steps, or blocks of the above described method(s) can be combined, separated, and/or performed in a different order from that described above, without departing from the examples of the present disclosure. 
     While various examples have been described above, it should be understood that they have been presented by way of example only, and not limitation. Thus, the breadth and scope of a preferred example should not be limited by any of the above-described examples, but should be defined only in accordance with the following claims and their equivalents.