Background

[0001] Reference marks may be a representation of data. Reference marks may include markings that may be scanned by a computing device to extract payload information.

[0002] Figure 1 illustrates an example controller for reference mark

verifications consistent with the disclosure.

[0003] Figure 2 illustrates an example reference mark including expected location information consistent with the disclosure.

[0004] Figure 3 illustrates an example flow chart for reference mark verifications consistent with the disclosure.

[0005] Figure 4 illustrates an example processing resource and a memory resource for reference mark verifications consistent with the disclosure.

[0008] Figure 5 illustrates an example method for reference mark verifications consistent with the disclosure.

Detailed Description

[0007] Reference marks may be generated to include information relating to multiple entities. For example, reference marks may include information relating to entities such as, objects, locations, businesses, utilities, directions, instructions, data, etc. As used herein, the term“reference mark” refers to a mark that may be generated to include information related to the entities. Some examples of reference marks may be fiducial marks, 1 D barcodes (e.g., Code 128, Code 39, UPC, etc.), 2D bar codes (e.g., Data Matrix, PDF417, Aztec, Quick Response (QR) codes,

Maxicode, etc.), and images carrying digital watermarks (e.g., digital fingerprinting techniques). In some examples, reference marks may be embedded with location information.

[0008] For example, a reference mark may be embedded with information (e.g., a payload) such as latitude and longitude of a particular location. In other examples, the reference mark may include information relating to a specific portion of a building to indicate a particular location or object. For example, a reference mark may be affixed to a support post in a building to indicate the presence of a utility contained within the support post, and the reference mark may include information such as,“Building 4, Floor 2, Post J2, water line”. In an instance where the reference mark becomes dislodged, and/or subsequently remounted in a different location, the information regarding the location of the water line becomes inaccurate.

[0009] For example, reference marks may become dislodged over time, initially mispositioned, mispositioned by well-meaning and/or nefarious individuals.

In these incidences, the mispositioned reference mark is no longer useful and may cause error by misidentifying locations because the information included in the reference mark is no longer relevant to its current (mispositioned) location. As used herein, the term“current location” refers to the location of a reference mark at the time it is scanned. Said differently, a mispositioned reference mark may cause error, wasted time, and resources if it is scanned and interpreted as if it is correctly positioned.

[0010] Examples herein describe including placement information with the payload of the reference mark, which may be verified when the reference mark is scanned. As used herein, the term“verify” refers to a determination of whether the reference mark is positioned where it is expected to be positioned, or if the reference mark is mispositioned. For example, a reference mark may be scanned at a current location to verify whether the reference mark has been mispositioned (or is currently in the expected, original, location). As used herein, the term“scan” and“scanned” refers to observing, detecting, regarding, examining, extracting, identifying, etc. features and/or characteristics of an entity (e.g., a location and/ or an area). The term“scan” and“scanned” also refers to a controller (and/or a user/administrafor) extracting information from a reference mark. As used herein, the term“controller” refers to a computing device that may contain a processing resource or a memory resource to execute instructions.

[0011] For example, an area may be scanned by a controller (e.g., a computing device) and/or an administrator (e.g., a user) to determine where a reference mark can be placed. As mentioned, the determined location may correspond to the information contained in the reference mark. For example, a reference mark including information about a gas line in a building may be positioned

7 at a specific location in the building such that the gas line may be located when the reference mark is scanned. Thus, the area may be scanned, and the location to place the reference mark may be selected based on the location of the gas line in the building; and the selected location for the reference mark may be included as expected location information (ELI) with the reference mark.

[0012] As used herein, the term“expected location information” and/or“ELI” refers to information embedded into the reference mark to communicate where the reference mark is supposed to be positioned. For example, the ELI may include an expected location and expected features of the expected location. As used herein, the term“expected location” refers to the original location selected for placement of the reference mark and the“expected features” refer to the features of the expected location.

[0013] For example, the selected area for the reference mark may include a selected location of a north facing wall (which becomes the expected location in the ELI). In this example, the features to identify the placement of the reference mark may be one meter from the floor and one meter to the right of an outlet on the north facing wail (which become the expected features of the ELI). Thus, In this example, the ELI may include the expected location“north facing wall” and the expected features“one meter from the floor and one meter to the right of an outlet”. In this way, the reference mark may be scanned for specific information (e.g., the location of the gas line) and verified that the information is relevant based on a comparison between the ELI and the current location of the reference mark. Specifically, if the reference mark at the time it is scanned (at its current location) is located on a north facing wall, one meter from the floor and one meter to the right of an outlet, the reference mark is likely in the intended location. In contrast, if the information in the ELI and the location features of the current location of the reference mark do not match, the location of the reference mark is not valid (e.g., it has been

mispositioned).

[0014] In this way, a current location of a reference mark may be validated by extracting the ELI from the reference mark and comparing the features of the current location of the reference mark to the ELL If there is a match between these features, the reference mark has not been mispositioned, and the information included in the reference mark may be accurate if there are discrepancies between the ELI of the reference mark and the current location features, the reference mark may have been mispositioned, thus the information included in the reference mark may be inaccurate. While examples described herein describe specific measurement values and/or qualitative values, many different values are contemplated herein, and the quantifies and values may be more or less than those mentioned by example.

[001 S] Figure 1 illustrates an example controller 100 for reference mark verifications consistent with the disclosure. The controller 100 may scan an area 106 for a location 108 including location features 1 10 to position a reference mark 1 12. The reference mark 1 12 may include a payload 1 14 and expected location information (ELI) 1 16. The ELI 116 may include expected features 1 18 related to an expected location 120. The controller 100 may include a processing resource to execute instructions stored on a memory resource to verify whether the expected location 120 and the location 108 are the same location.

[0016] As mentioned herein, the controller 100 may include a processing resource. For example, the processing resource may be central processing units (CPUs), semiconductor-based microprocessors, and/or other hardware devices suitable for retrieval and execution of instructions stored in a memory resource (e.g., in a non-transitory computer readable medium). The example processing resource may fetch, decode, and execute instructions. As an alternative, or in addition to, retrieving and executing instructions, the example processing resource may include an electronic circuit that may include electronic components for performing the functionality of executed instructions

[0017] In some examples, the processing resource may be a plurality of hardware processing units that may cause machine-readable instructions to be executed. The processing resource may include central processing units (CPUs) among other types of processing units. The memory resource may be any type of volatile or non-volatile memory or storage, such as random-access memory (RAM), flash memory, storage volumes, a hard disk, or a combination thereof.

[0018] In addition to, or in place of, the execution of executable instructions, various examples of the disclosure can be performed via one or more devices (e.g., one or more controllers) having logic. As used herein,“logic” is an alternative or additional processing resource to execute the actions and/or functions, etc., described herein, which includes hardware (e.g., various forms of transistor logic, application specific integrated circuits (ASICs), Field Programmable gate Array (FPGA), etc.), as opposed to computer executable instructions (e.g., software, firmware, etc.) stored in memory and executable by a processor. It is presumed that logic similarly executes instructions for purposes of the embodiments of the present disclosure. In some examples, the controller 100 may determine a location 108 of an area 106 to place a reference mark 112.

[0019] As used herein, the term“area” refers to a region that may be delineated into portions with multiple levels of specificity. For example, an area 106 may be a building which may include multiple locations 108 (e.g , floors of the building). As used herein, the term“location” refers to a portion of an area 106. For example, an area 106 may be a particular room in a building and the particular room may include multiple desks within the room where each desk in the room may be a location 108. In some examples, a reference mark 112 may be placed in a location 108 such that the payload 114 of the reference mark 112 may provide information specific to the location 108.

[0020] As used herein, the term“payload” refers to data that may be transmitted which may include a message. In some examples, the payload 114 may include information relating to the location 108 where the reference mark 112 is placed. For example, a payload 114 of a reference mark 112 may include information relating to the site of a gas line within an area 106 (e.g., a room). In this example, the location 108 (e.g., a particular wall) within the area 106 (e.g., the room) where the gas line is located may be where the reference mark 112 is placed. Thus, the reference mark 112 may be placed in the location 108 such that when the payload 114 is scanned, the site of the gas line may be communicated via the payload 114 of the reference mark 112. The location 108 where the reference mark 112 is placed may include features which may be added to the reference mark 112 to verify that the reference mark 112 is in the intended location 108. Thus, the payload 114 is relevant to the location 108 when the reference mark is correctly positioned at the location 108. The location features 110 of the location 108 may be identified to verify the location of the reference mark 112.

[0021] As used herein, the term“features of the location” and/or location features” are characteristics relating to the specific location 108 where the reference mark 112 is to be placed. The location features 110 may be a plurality of location features 110 and may be referred herein collectively as location features 110. Some examples of location features 110 may be physical location features, location characteristics, and/or qualitative features. As used herein, the term“physical location features” refers to features such as electrical outlets, an adjacent structure, a doorway, a floor, a wall, a vent, a doorstop, a window, and/or a distance between the reference mark 112 and the physical feature, etc. In other examples, the location features 110 may be location characteristics. As used herein, the term“location characteristics” refer to a description of the location (e.g., a cardinal direction, and/or GPS location, a longitude and latitude, etc.). Some examples of location

characteristics may be a type of the location 108. For example, a permanent wall, a moveable wail (e.g., a cubical wall), a material of the location (e.g., concrete, piaster, brick, fabric, plastic, etc.) in another example, the location features 110 may be qualitative features. As used herein, the term“qualitative features” refer to characteristics of the location that may be expressed categorically or as

approximate. Some examples of qualitative features may be a color of a background where the reference mark is located, a color of a location feature (e.g., a physical feature), a color of an adjacent feature of the location, a general position at a location (e.g., low, medium, high, beginning, middle, end, etc.).

[0022] When a location 108 is selected for placement of a reference mark 112, the controller 100 may generate the reference mark 112 to include the payload 114 and the ELI 116. The controller 100 and/or an administrator may print the reference mark 112 to include the selected location 108. The ELI 116 may be included as part of the payload 114 or as a separate portion of the reference mark 112 that is scanned when the payload 114 is scanned. As mentioned, the ELI 116 refers to information embedded into the reference mark 112 to communicate where the reference mark 112 is supposed to be positioned. For example, the ELI 116 may include an expected location 120 and expected features 118 of the expected location 120, where the expected location 120 refers to the original location selected for placement of the reference mark 112, and the expected features 118 refer to the features of the expected location 120. For example, the ELI 116 may include a distance between a physical feature (e.g., an expected feature 118) included in the expected location 120 and the position of the reference mark 112 within the expected location 120. In some examples, the location characteristics (e.g., location features 110) of the location 108 and the ELI 116 may both include qualitative features corresponding to a color of the location 108 (e.g., and the expected location 120. In other words, the expected location 120 is the same as the original location 108 when the reference mark 112 has not been moved or altered. Similarly, the expected features 118 may be the same as the location features 110 when the reference mark 112 has not been moved or altered.

[0023] For example, assume the reference mark 112 may be determined to be placed on a particular wall (e g., a location 108), one meter from a floor, and one meter to the right of an outlet (e.g., a location feature 110 of the location 108). In this example, the ELI 116 may be the expected location 120 is the particular wail and the expected features 118 are the reference mark 112 being one meter from the floor, and one meter to the right of the outlet. As mentioned, the ELI 116 may be included with the payload 114 and/or a separate portion of the payload 114, and the reference mark 112 may be generated by an imaging device within the area 106 or remote from the area 106. The generated reference mark 112 may include a payload 114 that is relevant to the determined location 108, thus the ELI 116 reflects the expected location 120 as the location 108 when the reference mark 112 is generated. The generated reference mark 116 may be positioned at the location 108 and verified.

[0024] As mentioned, a location 108 and location features 110 of a correctly positioned reference mark 112 may match the ELI 116 when the reference mark is correctly positioned. In the event that a reference mark 112 is moved,

mispositioned, becomes dislodged, etc. the location 108 and the location features 110 may change and therefore no longer match the ELI 116. in this instance, the payload 114 may no longer be relevant to the location 108, thus the reference mark 112 may be useless. To avoid error that may be caused by a mispositioned reference mark 112, the controller 100 may scan the reference mark 112 to verify the location. Based on a comparison of the ELI 116, and observations of the location features 110 of the location 108 of the reference mark 112 at the time of scanning, determine if the payload 114 may be considered accurate.

[0025] For example, to verify the location of the reference mark 112 and determine that the payload 114 information is relevant to the current location 108, the controller 100 may extract the ELI 116 from the reference mark 112 positioned at the location 108. For example, since the ELI 116 includes the expected location 120 at the time the reference mark 112 was generated, the payload 114 may be relevant to the expected location 120. Thus, the controller 100 may identify location features 110 of the current location 108 to compare to the ELI 116. For example, the identified location features 110 may include a distance between a physical location features 110 of the location 108 and the position of the reference mark 112 within the location 108 (at the time of scanning). Specifically, the controller 100 may identify that at the time the reference mark 112 was scanned, the location features 110 included the reference mark 112 being on a particular wail, one meter from the floor, and one meter to the right of a doorway. Using this information, the controller 100 may compare the ELI 116 to the identified location features 110 of the location 108, where the ELI 116 includes information related to expected features 118 of an expected location 120 of the reference mark 112. Specifically, the controller 100 may determine that the expected location 120 is a particular wail, and the expected features 118 are that the reference mark may be one meter from the floor, and one meter to the right of a doorway. Thus, the controller 100 may verify the location 108 of the reference mark 112 based on the comparison of the identified location features 110 of the location 108 and the ELI 116.

[0026] For example, based on the comparison of the identified location features 110 of the location 108 at the time the reference mark 112 was scanned, and the ELI 116, the controller 100 may determine that the identified location features 110 and the expected features 118 of the ELI 116 are the same features based on the comparison in this way, the payload 114 of the reference mark 112 at the time it was scanned may be considered accurate and relevant to its current location. Said differently, because the controller 100 has verified that the expected location 120 and the location 108 are the same, the controller may determine that the payload 114 includes information corresponding to the expected location 120 and the location 108 at the time the reference mark 112 was scanned for verification. While examples described in connection with Figure 1 describe specific

measurement value (e.g., one meter, etc.), many different values are contemplated herein and the quantities and values may be more or less than those mentioned by example.

[0027] Reference mark verifications according to the disclosure may verify if a reference mark 112 has been misposifioned or if the reference mark 112 is currently in the intended location by comparing the ELI 116 to the current location of the reference mark in this way, the accuracy of the information included in the reference mark 112 may be determined by observing the location features 110 where the reference mark 112 is currently located to the ELI 116 This may prevent error caused by assuming a reference mark 112 is in the intended location when in fact it may have been misposifioned. [0028] Figure 2 illustrates an example reference mark 212 including expected location information (ELI) 216 consistent with the disclosure. Although not shown in Figure 2 for clarity and so as not to obscure examples of the disclosure, a controller (e.g., the controller 100) may be included in examples described in Figure 2. Figure 2 illustrates a location 208 where a reference mark 112 (note: not illustrated to scale) may be positioned on a wall 213 (e.g., a location feature 110 of the location 108) adjacent to an outlet 210 (e.g , a location feature 110), where the distance between the reference mark 212 and the outlet 210 is a distance 211 (e.g., location feature 110). The reference mark 212 may include a payload 214 that may be relevant to the location 208.

[0029] For example, the payload 214 may include information about a utility behind the wail 213 of the location 208. As used herein, the term“utility” refers to an component used for a specific function. Examples of utilities may include water pipes, electrical wiring, natural gas lines etc. Thus, the information included in the payload 214 is relevant when the reference mark 212 remains at the location 208. The location 208 of the reference mark 212, and therefore the information of the payload 214 may be verified by scanning the reference mark 212 and comparing the ELI 216 to observed features of the current location of the reference mark 212.

[0030] For example, the reference mark 212 may be scanned and the ELI

216 may be extracted. For example, a reference mark 212 may be scanned to determine a location of a utility which may be included on the payload 214 of the reference mark. The physical features of the expected location 218 may include the wail 213 and the outlet 210 where the outlet 210 is the distance 211 to the right of the reference mark 212. In this example, the controller (e.g., the controller 100) and/or an administrator may observe the current location of the reference mark 212 at the time of scanning (in this instance, the location 208) and determine that the ELI 216 and the location features (the wall 213, the distance 211 , and the outlet 210) match the EL! 216. Said another way, the controller may determine, based on the ELI 216, a first distance between the physical feature of the expected location 218 and the position of the reference mark 212 within the expected location, and determine a second distance 211 between the physical feature of the location (e.g., the outlet 210) and the position of the reference mark within the location 208, and determine if the first distance and the second distance are the same. In this example, the first distance and the second distance are the same when the first distance and the second distance are within a predetermined threshold.

[0031] For example, assume that the ELI 218 may include that the physical feature of the expected location 218 is an outlet located 0.8 meters to the right of the expected location of the reference mark 212. The controller may include a threshold quantity of 0.2 meters that the distance 211 of the location 208 may be over and/or under. Specifically, the controller may determine the ELI 216 distance is 0.8 meters and the distance 211 is 1 meter, thus the outlet is positioned to the right of the reference mark 212 within a threshold distance in this instance, the controller may verify that the reference mark 212 is in the expected location, and the payload 214 may be accurate in contrast, if the ELI 216 includes that the physical feature of the expected location 218 is an outlet that is 0.5 meters to the right of the reference mark, and the controller determines that the distance 211 is one meter, the controller may verify that the reference mark has been mispositioned, thus the payload 214 may not be reliable as the ELI 218 and the distance 211 are outside the threshold distance. In some examples, the ELI 216 may include qualitative physical features of the expected location 218.

[0032] For example, the ELI 216 may include information that the wall 213 is of the color red. In this example, the controller may compare the color of the wall 213 where the reference mark 212 is currently located to the color of the wail 213 in the ELL The controller may include a database to compare the color of the wail 213 to colors (and/or other qualitative features) stored in the database. For example, the controller may include a database of the International Commission on Illumination (Cl BLAB) color information, or a database of colors corresponding to wavelengths and/or to a digital numerical value, etc. in this way, the controller may determine a color of the wail 213 and compare if to the ELI 216 utilizing a database in the controller. In other words, the controller may determine that the ELI 216 indicates that the reference mark is expected to be located on a red background, the controller may scan the current location 208 of the reference mark 212 and determine that the wail 213 is green. The controller may utilize the database to determine that the red background in the ELI 216 is not the same as the green wall 213, thus the reference mark may be mispositioned, and the payload 214 may no longer be relevant. In other examples, the distance 211 may refer to a general position and/or the distance 211 may be approximate (e.g., within a threshold level of accuracy). [0033] For example, the ELI 216 may include that the physical feature of the expected location 218 is an outlet located in a middle of a hallway. The ELI 216 may include information to which general quantities correspond. In some examples, the payload 214 may include information relating to a general location, where the location 208 of the reference mark 212 may be within the general location.

Specifically, the payload 214 of a reference mark 212 may refer to the middle of a 30 meter hallway. In this example, the controller may scan the reference mark 212 to extract the ELI 216 form the reference mark 212 and reference a database which may include quantities corresponding to general terms (e.g., low, medium, high, beginning, middle, and end, etc.), where the middle of a 30 meter hallway corresponds to a range of 11 meters to 20 meters from one end of the 30 meter hallway. When the current location of the reference mark 212 is determined to be between 11 and 20 meters, the controller may determine that the reference mark 212 is in the intended location, thus the payload 214 may be relied upon for the information contained thereon.

[0034] Reference mark verifications according to the disclosure provide examples to determine if a payload 214 may be accurate. In some instances, the information in the ELI 216 is qualitative and may be compared to the qualitative information of the current location 208 of the reference mark 212. Examples where the qualitative information of the ELI 216 and the qualitative information of the current location 208 do not match may indicate that the reference mark may have been dislodged, and/or subsequently remounted in a different location, thus the information of the payload 114 may be inaccurate.

[0035] Figure 3 illustrates an example flow chart for reference mark verifications consistent with the disclosure. Figure 3 illustrates a controller 300 which may include similar features of the controller 100 of Figure 1. The controller 300 (and/or an administrator) may scan an area (e.g., the area 106) to determine a location (e.g., the location 108) to place a reference mark (e.g., the reference mark 112).

[0036] The reference mark may include a payload (e.g., the payload 114) that may include information relevant to the specific location to be selected. For example, the payload may include information about a utility within a building. The controller 300 may scan the location including the utility for location features (e.g., the location features 110) to determine a location to place the reference mark. The controller 300 may include the determined location and the location features to create an ELI (e.g., the ELI 116} to be included in the reference mark. The controller 300 may generate the reference mark and the reference mark may be placed at the determined location. For example, the controller 300 may execute Instructions to print the reference mark using an imaging device within the area or remote from the area, and the generated reference mark may be attached at the determined location. In this example, at the time when the generated reference mark is generated and placed at the intended location the determined location and the ELI are the same. The controller 300 may scan the reference mark to verify whether the reference mark is in the intended location.

[0037] For example, at block 330 the controller 300 may extract the ELI from the reference mark and at block 334 the controller may scan the current location of the reference mark. At block 332, the controller 300 may determine the expected location feature (e.g., the expected features 118) from the ELL For example, the expected features may be the location features that were scanned when a location was originally determined for placement of the reference mark, in this instance assume that the expected feature is an outlet that is a first distance one meter to the right of the reference mark. At block 336, the controller 300 may determine location features of the location where the reference mark currently located. For example, the controller may scan the current location of the reference mark to determine if there are any features that match the ELI. The controller 300 may compare the expected location feature (box 332) to the determined location feature (block 336) to verify the reference mark.

[0038] For example, at block 338, the controller 300 may compare the expected location feature from the ELI (the outlet, a first distance one meter to the right of the reference mark), to the location features of the current location. The controller 300, at block 340, may verify whether the current location and the expected location (from the ELI) are the same based on the comparison. For example, assume that the controller 300 determined that an outlet exists at a second distance within the current location of the reference mark. The controller 300 may compare the second distance (between the outlet in the current location) and the first distance one meter to the right of the reference mark.

[0039] If the controller 300 determines that the first distance and the second distance are not the same within a threshold amount (“No” at 342) the controller 300 may determine that the reference mark is not at the expected location. This may indicate that the reference mark has been repositioned, moved, altered, or otherwise tampered with and the payload of the reference mark may not be reliable as the reference mark is not at the originally determined location. If, however, the controller 300 determines that the first distance and the second distance are the same within a threshold amount (“Yes” at 348) the controller 300 may determine that the reference mark is at the expected location. This may indicate that the reference mark has not been repositioned, moved, altered, or otherwise tampered with and the payload of the reference mark may be reliable as the reference mark is currently located at the originally determined location.

[0040] Reference mark verifications according to the disclosure provide examples to quickly determine if a payload is accurate. The reference mark may include a payload that corresponds to a particular location. When the reference mark is placed at that location, the reference mark verification described in connection with Figure 3 provide examples to determine of the reference mark is in the intended location.

[0041] Figure 4 illustrates an example processing resource and a memory resource for reference mark verifications consistent with the disclosure. Figure 4 includes a processing resource 402 and a memory resource 404. The processing resource 402 may be a hardware processing unit such as a microprocessor, microcontroller, application specific instruction set processor, coprocessor, network processor, or similar hardware circuitry that may cause machine-readable instructions to be executed. In some examples, the processing resource 402 may be a plurality of hardware processing units that may cause machine-readable instructions to be executed. The processing resource 402 may include central processing units (CPUs) among other types of processing units. The memory resource 404 may be any type of volatile or non-volatile memory or storage, such as random-access memory (RAM), flash memory, read-only memory (ROM), storage volumes, a hard disk, or a combination thereof.

[0042] The memory resource 404 may store instructions thereon, such as instructions 452, 454, 458, and 458. WTien executed by the processing resource 402, the instructions may cause a controller (e.g , the controller 100 of Figure 1) to perform specific tasks and/or functions. For example, the memory resource 404 may store instructions 452 which may be executed by the processing resource 402 to cause the controller to determine ELI (e.g., the ELI 116) from a reference mark (e g., the reference mark 112) positioned at a location (e.g., the location 108), where the ELI includes information related to an expected physical feature (e.g., the expected features 118) of an expected location (e.g., the expected location 120) of the reference mark. For example, the expected location may be a moveable cubicle wail, and the expected physical features may be that the wail is covered in fabric and oriented facing a north window. The controller may verify that the expected location of the reference mark and the current location of the reference mark are the same such that the payload (e.g., the payload 114) may be accurate.

[0043] For example, the memory resource 404 may store instructions 454 which may be executed by the processing resource 402 to cause the controller to identify a physical feature of the location (e.g., the location features 110), where the location is the current location of the reference mark. For example, the controller (or a user/ administrator) may determine that the features of the current location are a wail covered in fabric and oriented facing a south window. The controller may compare the expected physical features with the determined physical features.

[0044] For example, the memory resource 404 may store instructions 456 which may be executed by the processing resource 402 to cause the controller to compare the expected physical location feature of the expected location to the identified physical location features. For example, the controller may determine that the identified physical features are different based on the comparison.

[0045] For example, the memory resource 404 may store instructions 458 which may be executed by the processing resource 402 to cause the controller to verify the location of the reference mark based on the based on the comparison of the identified physical feature of the location and the physical feature included in the ELI. In this example, the controller may verify that the reference mark is not where it is expected to be located because the identified physical features indicated that the reference mark is oriented facing a south window and the expected physical feature indicated that the reference mark to be oriented facing a north window. This may indicate that the cubical walls have been rearranged, and/or the reference marks have been otherwise moved. In response to that verification, the payload of the reference mark may not be reliable.

[0046] Reference mark verifications according to the disclosure may verify if a reference mark has been mispositioned or if the reference mark is in the intended location by comparing ELI to the current location of the reference mark in this way, the accuracy of the information include in the reference mark may be quickly determined by observing the location features where the reference mark was currently located to the ELI. This may prevent error cause my assuming a reference mark is in the intended location when in fact it has been mispositioned.

[0047] Figure 5 illustrates an example method for reference mark verifications consistent with the disclosure. A controller (e.g , the controller 100) may verify the current location (e.g., the location 108) of a fiduciary mark (e.g., the reference mark 112) by scanning the area (e.g., the area 108} around the fiduciary mark and comparing the current location of the fiduciary mark to the ELI (e.g., the ELI 118) to determine if the payload (e.g., the payload 114) of the fiduciary mark is relevant to the current location of the fiduciary mark. For example, at 572, the method 570 may include identifying location characteristics (e.g., the location features 110) of a location by scanning an area around the location. For example, the controller may determine that the fiduciary mark is affixed to a purple background. The controller may scan the fiduciary mark to extract the ELI from the fiduciary mark.

[0048] For example, at 574, the method 570 may include determining ELI from the fiduciary mark positioned in the location (the current location affixed to the purple wall). For example, the controller may determine that the ELI includes expected features (e.g., the expected features 118) of a green background. The controller may include a database to compare the color schemes against known values, thus determining the difference between purple and green. Thus, the controller may compare the identified location characteristics to the ELI.

[0049] For example, at 576, the method 570 may include comparing the expected location characteristics (the green background) of the expected location to the location characteristics (the purple background) of the location based on the scan of the location. For example, the controller may determine based on known values stored in a database that the colors purple and green are not the same. Based on this comparison the controller may determine that the payload of the fiduciary mark cause an error if relied upon.

[0050] For example, at 578, the method 570 may include determining that the fiduciary mark has moved based on the comparison of the expected location (green background) characteristics and the location characteristics (purple background) identified by the scan. For example, the controller may determine that the fiduciary

13 mark has been moved, was incorrectly positioned, etc. Thus, the payload may not be reliable.

[0051] In the foregoing detailed description of the disclosure, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration how examples of the disclosure may be practiced. These examples are described in sufficient detail to enable those of ordinary skill In the art to practice the examples of this disclosure, and it is to be understood that other examples may be utilized and that process, electrical, and/or structural changes may be made without departing from the scope of the disclosure.

[0052] The figures herein follow a numbering convention in which the first digit corresponds to the drawing figure number and the remaining digits identify an element or component in the drawing. Similar elements or components between different figures may be identified by the use of similar digits. For example, 102 may reference element“02” in Figure 1 , and a similar element may be referenced as 202 in Figure 2.

[0053] Elements illustrated in the various figures herein can be added, exchanged, and/or eliminated so as to provide a plurality of additional examples of the disclosure. In addition, the proportion and the relative scale of the elements provided in the figures are intended to illustrate the examples of the disclosure and should not be taken in a limiting sense. As used herein, the designator“N”, particularly with respect to reference numerals in the drawings, indicates that a plurality of the particular feature so designated can be included with examples of the disclosure. The designators can represent the same or different numbers of the particular features. Further, as used herein, "a plurality of an element and/or feature refers to more than one of such elements and/or features.

[0054] The above specification, examples and data provide a description of the method and applications and use of the system and method of the present disclosure. Since many examples can be made without departing from the spirit and scope of the system and method of the present disclosure, this specification merely sets forth some of the many possible example configurations and implementations.