# US 10,481,259 B2 · Tracking targets on a sonar image > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,481,259 B2 - Document ID: US10481259B2 - Status: Granted - Kind: B2 - Application number: 14/026,400 - Filed: 2013-09-13 - Published: 2015-03-19 - Granted: 2019-11-19 - Earliest claimed: 2013-09-13 - Assignees: Navico Holding AS - Applicants: Navico Holding AS - Inventors: Robert Langford-Wood - Web page: https://patentgrep.com/patent/US10481259B2 ## CPC - G01S 15/66: Sonar tracking systems - G01S 7/56: Display arrangements {(short-range imaging G01S7/52053)} - G01S 7/6218: {providing two-dimensional coordinated display of distance and direction} - G01S 7/6263: {in which different colours are used} - G01S 7/6272: {producing cursor lines and indicia by electronic means} - G01S 15/89: for mapping or imaging - G01S 15/93: for anti-collision purposes - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES ## Abstract Various implementations described herein are directed to a computer-implemented method for tracking one or more targets on a sonar image. The method may include displaying the sonar image on a computer screen, receiving a command to track the one or more targets on the sonar image, storing the locations of the one or more targets relative to a vessel and displaying a symbol around a respective one of the one or more targets. ## Claims ### Claim 1 A method for tracking one or more targets on a sonar image, the method comprising: receiving first sonar data from a sonar system of a vessel at a first time, wherein the first sonar data is generated from a plurality of sonar returns from an underwater environment relative to the vessel based on a first sweep of the underwater environment by the sonar system, wherein at least one transducer of the sonar system is configured to mechanically rotate 360 degrees during the first sweep; processing the first sonar data from the first sweep to form a first sonar image that shows a representative plan view of the underwater environment relative to the vessel, wherein the first sonar image is formed using pixel coordinates for each of the plurality of sonar returns of the first sonar data, wherein each pixel coordinate defines a color value that directly correlates to at least an amplitude of a corresponding sonar return; displaying the first sonar image on a computer screen; identifying one or more targets in the first sonar image by determining that a contrast between the color value of one or more pixel coordinates of the first sonar image and a background color value of the first sonar image is greater than a predetermined threshold; receiving user input to a user interface associated with the screen, wherein the user input indicates a desire to track the one or more targets on the first sonar image; determining a first location of the one or more targets based on the pixel coordinates of the first sonar image associated with the one or more targets; receiving second sonar data from the sonar system of the vessel at a second time following the first time, wherein the second sonar data is generated from a plurality of sonar returns from the underwater environment relative to the vessel based on a second sweep of the underwater environment by the sonar system, wherein the at least one transducer of the sonar system is configured to mechanically rotate 360 degrees during the second sweep; processing the second sonar data from the second sweep to form a second sonar image that shows a representative plan view of the underwater environment relative to the vessel, wherein the second sonar image is formed using pixel coordinates for each of the plurality of sonar returns of the second sonar data, wherein each pixel coordinate defines a color value that directly correlates to at least an amplitude of a corresponding sonar return; displaying the second sonar image on the computer screen; re-identifying the one or more targets within the second sonar image based on at least a contrast between the color value of one or more pixel coordinates of the second sonar image and a background color value of the second sonar image by identifying at least one of shape, size, color, or speed associated with one or more pixel coordinates that substantially matches one or more predetermined shapes, speeds, colors or sizes of the one or more targets; determining a second location of the one or more targets based on the pixel coordinates of the second sonar image associated with the one or more targets; and tracking the one or more targets by at least storing the first location and the second location of the one or more targets in a memory. ### Claim 2 (depends on 1) The method of claim 1, further comprising: displaying a first symbol around each of the identified one or more targets in the first sonar image; and displaying the same symbol around each of the corresponding identified one or more targets in the second sonar image. ### Claim 3 (depends on 2) The method of claim 2, wherein the symbol is an outline of a geometric shape. ### Claim 4 (depends on 1) The method of claim 1, wherein receiving the user input comprises receiving a selection of one or more pixel coordinates in the first sonar image. ### Claim 5 (depends on 4) The method of claim 4, wherein receiving the user input occurs prior to identifying the one or more targets. ### Claim 6 (depends on 1) The method of claim 1, further comprising steering the vessel toward the one or more targets. ### Claim 7 (depends on 6) The method of claim 6, wherein the vessel is steered by an autopilot system. ### Claim 8 (depends on 1) The method of claim 1, further comprising: comparing the second location of the one or more targets to one or more guard zones relative to the vessel; and providing, via the user interface, a warning in an instance in which the second location is within the one or more guard zones such that the one or more targets has entered at least one of the one or more guard zones. ### Claim 9 (depends on 1) The method of claim 1, wherein determining the first location comprises determining the first location relative to the earth, and wherein determining the second location comprises determining the second location relative to the earth. ### Claim 10 (depends on 1) The method of claim 1, wherein identifying the one or more targets comprises summing the contrasts of a plurality of pixel coordinates that are each within a predetermined minimum area. ### Claim 11 A non-transitory computer-readable medium having stored thereon computer-executable instructions which, when executed by a computer, cause the computer to: receive first sonar data from a sonar system of a vessel at a first time, wherein the first sonar data is generated from a plurality of sonar returns from an underwater environment relative to the vessel based on a first sweep of the underwater environment by the sonar system, wherein at least one transducer of the sonar system is configured to mechanically rotate 360 degrees during the first sweep; process the first sonar data from the first sweep to form a first sonar image that shows a representative plan view of the underwater environment relative to the vessel, wherein the first sonar image is formed using pixel coordinates for each of the plurality of sonar returns of the first sonar data, wherein each pixel coordinate defines a color value that directly correlates to at least an amplitude of a corresponding sonar return; display a first sonar image on a computer screen; identify one or more targets in the first sonar image by determining that a contrast between the color value of one or more pixel coordinates of the first sonar image and a background color value of the first sonar image is greater than a predetermined threshold; receive user input to a user interface associated with the screen, wherein the user input indicates a desire to track one or more targets on the first sonar image; determine a first location of the one or more targets based on the pixel coordinates of the first sonar image associated with the one or more targets; receive second sonar data from the sonar system of the vessel at a second time following the first time, wherein the second sonar data is generated from a plurality of sonar returns from the underwater environment relative to the vessel based on a second sweep of the underwater environment by the sonar system, wherein the at least one transducer of the sonar system is configured to mechanically rotate 360 degrees during the second sweep; process the second sonar data from the second sweep to form a second sonar image that shows a representative plan view of the underwater environment relative to the vessel, wherein the second sonar image is formed using pixel coordinates for each of the plurality of sonar returns of the second sonar data, wherein each pixel coordinate defines a color value that directly correlates to at least an amplitude of a corresponding sonar return; display the second sonar image on the computer screen; re-identify the one or more targets within the second sonar image based on at least a contrast between the color value of one or more pixel coordinates of the second sonar image and a background color value of the second sonar image by identifying at least one of shape, size, color, or speed associated with one or more pixel coordinates that substantially matches one or more predetermined shapes, speeds, colors or sizes of the one or more targets; determine a second location of the one or more targets based on the pixel coordinates of the second sonar image associated with the one or more targets; and tracking the one or more targets by at least storing the first location and the second location of the one or more targets in a memory. ### Claim 12 (depends on 11) The non-transitory computer-readable medium of claim 11, further comprising executable instructions which, when executed by a computer, further cause the computer to identify the one or more targets by summing the contrasts of a plurality of pixel coordinates that are each within a predetermined minimum area. ### Claim 13 (depends on 11) The non-transitory computer-readable medium of claim 11, further comprising executable instructions which, when executed by a computer, further cause the computer to receive the user input by receiving a selection of one or more pixel coordinates in the first sonar image. ### Claim 14 An apparatus, the apparatus comprising: one or more processors; a computer screen; and a memory having stored thereon a plurality of executable instructions which, when executed by the one or more processors, causes the one or more processors to: receive first sonar data from a sonar system of a vessel at a first time, wherein the first sonar data is generated from a plurality of sonar returns from an underwater environment relative to the vessel based on a first sweep of the underwater environment by the sonar system, wherein at least one transducer of the sonar system is configured to mechanically rotate 360 degrees during the first sweep; process the first sonar data from the first sweep to form a first sonar image that shows a representative plan view of the underwater environment relative to the vessel, wherein the first sonar image is formed using pixel coordinates for each of the plurality of sonar returns of the first sonar data, wherein each pixel coordinate defines a color value that directly correlates to at least an amplitude of a corresponding sonar return; display a first sonar image on the computer screen; identify one or more targets in the first sonar image by determining that a contrast between the color value of one or more pixel coordinates of the first sonar image and a background color value of the first sonar image is greater than a predetermined threshold; receive user input to a user interface associated with the screen, wherein the user input indicates a desire to track one or more targets on the first sonar image; determine a first location of the one or more targets based on the pixel coordinates of the first sonar image associated with the one or more targets; receive second sonar data from the sonar system of the vessel at a second time following the first time, wherein the second sonar data is generated from a plurality of sonar returns from the underwater environment relative to the vessel based on a second sweep of the underwater environment by the sonar system, wherein the at least one transducer of the sonar system is configured to mechanically rotate 360 degrees during the second sweep; process the second sonar data from the second sweep to form a second sonar image that shows a representative plan view of the underwater environment relative to the vessel, wherein the second sonar image is formed using pixel coordinates for each of the plurality of sonar returns of the second sonar data, wherein each pixel coordinate defines a color value that directly correlates to at least an amplitude of a corresponding sonar return; display the second sonar image on the computer screen; re-identify the one or more targets within the second sonar image based on at least a contrast between the color value of one or more pixel coordinates of the second sonar image and a background color value of the second sonar image by identifying at least one of shape, size, color, or speed associated with one or more pixel coordinates that substantially matches one or more predetermined shapes, speeds, colors or sizes of the one or more targets; determine a second location of the one or more targets based on the pixel coordinates of the second sonar image associated with the one or more targets; and tracking the one or more targets by at least storing the first location and the second location of the one or more targets in the memory. ### Claim 15 (depends on 14) The apparatus of claim 14, wherein the plurality of executable instructions, when executed by the one or more processors, further cause the one or more processors to receive the user input by receiving a selection of one or more pixel coordinates in the first sonar image. ### Claim 16 (depends on 14) The apparatus of claim 14, wherein the plurality of executable instructions, when executed by the one or more processors, further cause the one or more processors to identify the one or more targets by summing the contrasts of a plurality of pixel coordinates that are each within a predetermined minimum area.