# US 10,311,580 B2 · Bed area extraction method and bed area extraction apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,311,580 B2 - Document ID: US10311580B2 - Status: Granted - Kind: B2 - Application number: 15/454,046 - Filed: 2017-03-09 - Published: 2017-10-19 - Granted: 2019-06-04 - Earliest claimed: 2016-04-18 - Assignees: Fujitsu Limited - Applicants: Fujitsu Limited - Inventors: Yasutaka Okada; Kimitaka Murashita - Web page: https://patentgrep.com/patent/US10311580B2 ## CPC - G06T 7/194: involving foreground-background segmentation - G06T 7/11: Region-based segmentation - G06T 7/12: Edge-based segmentation - G06T 7/60: Analysis of geometric attributes - G06T: IMAGE DATA PROCESSING OR GENERATION, IN GENERAL ## Abstract A bed area extraction method includes specifying, by a computer, a first part of a bed candidate area in an image based on a first line segment extracted from the image; setting a search range for searching a second line segment with reference to the bed candidate area which is determined based on the specified first part of the bed candidate area; and correcting the bed candidate area based on a disposition of the second line segment included in the set search range. ## Claims ### Claim 1 A non-transitory computer-readable recording medium having stored therein a program that causes a computer to execute a process, the process comprising: specifying a first part of a bed candidate area in an image based on first line segments which are extracted from the image; setting a search range for searching a second line segment with reference to the bed candidate area which is determined based on the specified first part of the bed candidate area; selecting the second line segment from among one or more first line segments, which are included in the first line segments and the search range, based on a disposition of the one or more first line segments; and correcting the bed candidate area based on a disposition of the second line, wherein the specifying includes specifying, as a part of the bed candidate area, a second part including one of short sides of the bed candidate area, the one of short sides corresponding to a head board attached to one end of a bed, wherein the head board has a certain thickness in a longitudinal direction of the bed candidate area, and wherein the setting includes setting, to the search range, an area surrounded by lines, the lines including a long side of the bed candidate area after rotation in which the bed candidate area is rotated by an angle depending on the thickness of the head board around a point corresponding to a midpoint of the one of short sides corresponding to a short side of the bed to which the head board is attached. ### Claim 2 (depends on 1) The non-transitory computer-readable recording medium according to claim 1, wherein the second part corresponding to the head board is a U-shaped portion. ### Claim 3 (depends on 1) The non-transitory computer-readable recording medium according to claim 1, further comprising acquiring a contour segment in the search range, the contour segment being determined to be a part of a contour of the bed in a case where an inclination of the contour segment with respect to a long side of the bed candidate area is equal to or larger than a predetermined angle, wherein the correcting includes correcting the bed candidate area in a case where the contour segment is acquired. ### Claim 4 (depends on 3) The non-transitory computer-readable recording medium according to claim 3, wherein the setting includes setting a search range for each of the long sides of the bed candidate area, and wherein the correcting includes correcting the bed candidate area in a case where the contour segment is acquired from each of the set search ranges when an angular difference between the inclination of the contour segment and a rotation angle of the bed candidate area is less than a predetermined value. ### Claim 5 (depends on 3) The non-transitory computer-readable recording medium according to claim 3, wherein the contour segment includes a line segment having a length equal to or longer than a predetermined length and being the longest line segment in the search range. ### Claim 6 (depends on 3) The non-transitory computer-readable recording medium according to claim 3, wherein the correcting includes correcting the bed candidate area by rotating the bed candidate area so that the long side is parallel to a direction of the contour segment. ### Claim 7 (depends on 1) The non-transitory computer-readable recording medium according to claim 1, wherein the angle depending on the thickness of the head board is an angle formed by a side, of the head board, corresponding to the one of short sides of the bed candidate area and a diagonal line in a cross section of the head board. ### Claim 8 (depends on 1) The non-transitory computer-readable recording medium according to claim 1, wherein a misalignment between a position, in the image, corresponding to the bed and the bed candidate area is represented by an angle of a difference between a direction of the head board and a direction of a line obtained by connecting two line segments which corresponds respectively to parts of two long sides of the head board, the two long sides being parallel to each other. ### Claim 9 A bed area extraction method, comprising: specifying, by a computer, a first part of a bed candidate area in an image based on first line segments which are extracted from the image; setting a search range for searching a second line segment with reference to the bed candidate area which is determined based on the specified first part of the bed candidate area; selecting the second line segment from among one or more first line segments, which are included in the first line segments and the search range, based on a disposition of the one or more first line segments; and correcting the bed candidate area based on a disposition of the second line segment, wherein the specifying includes specifying, as a part of the bed candidate area, a second part including one of short sides of the bed candidate area, the one of short sides corresponding to a head board attached to one end of a bed, wherein the head board has a certain thickness in a longitudinal direction of the bed candidate area, and wherein the setting includes setting, to the search range, an area surrounded by lines, the lines including a long side of the bed candidate area after rotation in which the bed candidate area is rotated by an angle depending on the thickness of the head board around a point corresponding to a midpoint of the one of short sides corresponding to a short side of the bed to which the head board is attached. ### Claim 10 (depends on 9) The bed area extraction method according to claim 9, wherein the second part corresponding to the head board is a U-shaped portion. ### Claim 11 (depends on 9) The bed area extraction method according to claim 9, further comprising: acquiring a contour segment in the search range, the contour segment being determined to be a part of a contour of the bed in a case where an inclination of the contour segment with respect to a long side of the bed candidate area is equal to or larger than a predetermined angle, wherein the correcting includes correcting the bed candidate area in a case where the contour segment is acquired. ### Claim 12 (depends on 9) The bed area extraction method according to claim 9, further comprising: wherein the setting includes setting a search range for each of the long sides of the bed candidate area, and wherein the correcting includes correcting the bed candidate area in a case where the contour segment is acquired from each of the set search ranges when an angular difference between the inclination of the contour segment and a rotation angle of the bed candidate area is less than a predetermined value. ### Claim 13 A bed area extraction apparatus, comprising: a processor configured to: specify a first part of a bed candidate area in an image based on first line segments which are extracted from the image; set a search range for searching a second line segment with reference to the bed candidate area which is determined based on the specified first part of the bed candidate area; select the second line segment from among one or more first line segments, which are included in the first line segments and the search range, based on a disposition of the one or more first line segments; and correct the bed candidate area based on a disposition of the second line segment, wherein the processor is configured to specify, as a part of the bed candidate area, a second part including one of short sides of the bed candidate area, the one of short sides corresponding to a head board attached to one end of a bed, wherein the head board has a certain thickness in a longitudinal direction of the bed candidate area, and wherein the computer configured to set, to the search range, an area surrounded by lines, the lines including a long side of the bed candidate area after rotation in which the bed candidate area is rotated by an angle depending on the thickness of the head board around a point corresponding to a midpoint of the one of short sides corresponding to a short side of the bed to which the head board is attached. ### Claim 14 (depends on 13) The bed area extraction apparatus according to claim 13, wherein the part including one of the short sides of the bed candidate area corresponding to the head board is a U-shaped portion.