# US 5,347,598 A · Image processing apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,347,598 A - Document ID: US5347598A - Status: Granted - Kind: A - Application number: 08/047,354 - Filed: 1993-04-19 - Granted: 1994-09-13 - Earliest claimed: 1987-03-20 - Assignees: Canon Kabushiki Kaisha - Inventors: Masami Ogawa - Web page: https://patentgrep.com/patent/US5347598A ## CPC - G06V 10/44: Local feature extraction by analysis of parts of the pattern, e.g. by detecting edges, contours, loops, corners, strokes or intersections; Connectivity analysis, e.g. of connected components - G06V: IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING ## Abstract In an image processing apparatus, an original image is extracted in the form of line segments divided by characteristic points, the extracted line segments are classified in accordance with the lengths of line segments connected to the characteristic points, and a frame is made in accordance with classification results. ## Claims ### Claim 1 An image processing apparatus comprising: line segment extracting means for extracting from an original image a plurality of line segments including characteristic points; classifying means for classifying the line segments extracted by said line segment extracting means in accordance with angles between the line segments connected to the characteristic points, wherein said classifying means classifies the line segments into parallel lines, other parallel lines, and tilted lines in accordance with the angles formed between the line segments connected to the characteristic points; frame making means for making a frame in accordance with the classification results of said classifying means; and numerical operating means for performing an operation on numerical information within the frame made by said frame making means. ### Claim 2 (depends on 1) An apparatus according to claim 1, further comprising a scanner for inputting the original image. ### Claim 3 (depends on 1) An apparatus according to claim 1, further comprising a keyboard for instructing the inputting of the original image. ### Claim 4 (depends on 1) An apparatus according to claim 1, further comprising a cathode ray tube for displaying the frame. ### Claim 5 (depends on 1) An apparatus according to claim 1, further comprising a printer for printing the frame. ### Claim 6 An image processing apparatus comprising: vector forming means for converting an original image into a set of vector line segments having initial and terminal points corresponding to characteristic points comprising end points, contact points, intersections, and branching points; rectangle extracting means for extracting vectors defining a rectangle on the basis of a connecting relationship between vector line segments belonging to the set of vector line segments, wherein said rectangle extracting means comprises: vector retrieving means for retrieving a horizontal or vertical vector from the vector line segments; vector tracing means for tracing a vertical or horizontal vector connected to the horizontal or vertical vector retrieved by said vector retrieving means, thereby extracting the vectors defining the rectangle; and numerical operating means for performing an operation on numerical information within each rectangle extracted by said rectangle extracting means in accordance with the position of said each rectangle. ### Claim 7 (depends on 6) An image processing apparatus according to claim 6, wherein said rectangular extracting means further extracts a tilted line. ### Claim 8 (depends on 6) An apparatus according to claim 6, further comprising a scanner for inputting the original image. ### Claim 9 (depends on 6) An apparatus according to claim 6, further comprising a keyboard for instructing the inputting of the original image. ### Claim 10 (depends on 6) An apparatus according to claim 6, further comprising frame making means for making a frame in accordance with the extracted rectangle. ### Claim 11 (depends on 10) An apparatus according to claim 10, further comprising a cathode ray tube for displaying the frame. ### Claim 12 (depends on 10) An apparatus according to claim 10, further comprising a printer for printing the frame. ### Claim 13 An image processing apparatus comprising: line segment extracting means for extracting from an original image a plurality of line segments including characteristic points; line segments selecting means for selecting line segments connected to one of the plurality of extracted characteristic points; classifying means for classifying the line segments selected by said line segments selecting means in accordance with angles between the selected line segments; storage means for storing classification results of said classifying means with the respective extracted line segments; frame making means for making a frame in accordance with the stored classification result; and numerical operating means for performing an operation on numerical information within the frame made by said frame making means. ### Claim 14 (depends on 13) An apparatus according to claim 13, wherein said classifying means classifies the line segments into parallel lines and tilted lines. ### Claim 15 (depends on 13) An apparatus according to claim 13, wherein the one of the plurality of characteristic points is a bent point. ### Claim 16 (depends on 13) An apparatus according to claim 13, wherein the one of the plurality of characteristic points is an intersection point. ### Claim 17 (depends on 13) An apparatus according to claim 13, wherein the one of the plurality of characteristic points is a branching point. ### Claim 18 (depends on 13) An apparatus according to claim 13, further comprising a scanner for inputting the original image. ### Claim 19 (depends on 13) An apparatus according to claim 13, further comprising a keyboard for instructing the inputting of the original image. ### Claim 20 (depends on 13) An apparatus according to claim 13, further comprising a cathode ray tube for displaying the frame. ### Claim 21 (depends on 13) An apparatus according to claim 13, further comprising a printer for printing the frame. ### Claim 22 An image processing apparatus comprising: line segment extracting means for extracting from an original image a plurality of line segments including characteristic points; line segments selecting means for selecting line segments connected to one of the plurality of extracted characteristic points; classifying means for classifying the line segments selected by said line segments selecting means in accordance with lengths of the selected line segments; storage means for storing classification results of said classifying means with the respective extracted line segments; frame making means for making a frame in accordance with the stored classification result; and numerical operating means for performing an operation on numerical information within the frame made by said frame making means. ### Claim 23 (depends on 22) An apparatus according to claim 22, wherein said classifying means classifies the line segments into parallel lines and tilted lines. ### Claim 24 (depends on 22) An apparatus according to claim 22, wherein the one of the plurality of characteristic points is a bent point. ### Claim 25 (depends on 22) An apparatus according to claim 22, wherein the one of the plurality of characteristic points is an intersection point. ### Claim 26 (depends on 22) An apparatus according to claim 22, wherein the one of the plurality of characteristic points is a branching point. ### Claim 27 (depends on 22) An apparatus according to claim 22, further comprising a scanner for inputting the original image. ### Claim 28 (depends on 22) An apparatus according to claim 22, further comprising a keyboard for instructing the inputting of the original image. ### Claim 29 (depends on 22) An apparatus according to claim 22, further comprising a cathode ray tube for displaying the frame. ### Claim 30 (depends on 22) An apparatus according to claim 22, further comprising a printer for printing the frame. ### Claim 31 An image processing apparatus comprising: vector forming means for converting an original image into a plurality of vector line segments; vector storing means for storing characteristic points including an initial point and a terminal point of each vector line segment converted by said vector forming means; rectangle extracting means for extracting vectors defining a rectangle on the basis of a connecting relationship between vector line segments belonging to the stored vector line segments, wherein said rectangle extracting means comprises: vector retrieving means for retrieving a horizontal or vertical vector from the vector line segments; vector tracing means for tracing a vector having the same point data as the characteristic points of the retrieved vector, thereby extracting the vectors defining the rectangle; and numerical operation means for performing an operation on numerical information within each rectangle extracted by said rectangle extracting means in accordance with the position of said each rectangle. ### Claim 32 (depends on 31) An apparatus according to claim 31, further comprising frame making means for making a frame in accordance with the extracted rectangle. ### Claim 33 (depends on 31) An apparatus according to claim 31, wherein the one of the plurality of characteristic points is a bent point. ### Claim 34 (depends on 31) An apparatus according to claim 31, wherein the one of the plurality of characteristic points is an intersection point. ### Claim 35 (depends on 31) An apparatus according to claim 31, wherein the one of the plurality of characteristic points is a branching point. ### Claim 36 (depends on 31) An apparatus according to claim 31, further comprising a scanner for inputting the original image. ### Claim 37 (depends on 31) An apparatus according to claim 31, further comprising a keyboard for instructing the inputting of the original image. ### Claim 38 (depends on 32) An apparatus according to claim 32, further comprising a cathode ray tube for displaying the frame. ### Claim 39 (depends on 32) An apparatus according to claim 32, further comprising a printer for printing the frame. ### Claim 40 A method for processing an image comprising the steps of: extracting from an original image a plurality of line segments including characteristic points; classifying the line segments extracted in said line segment extracting step in accordance with angles between the line segments connected to the characteristic points, wherein said classifying step classifies the line segments into parallel lines, other parallel lines, and tilted lines in accordance with the angles formed between the line segments connected to the characteristic points; making a frame in accordance with the classification results of said classifying step; and performing an operation on numerical information within the frame made in said frame making step. ### Claim 41 (depends on 40) A method according to claim 40, further comprising the step of inputting the original image with a scanner. ### Claim 42 (depends on 40) A method according to claim 40, further comprising the step of instructing the inputting of the original image with a keyboard. ### Claim 43 (depends on 40) A method according to claim 40, further comprising the step of displaying the frame with a cathode ray tube. ### Claim 44 (depends on 40) A method according to claim 40, further comprising the step of printing the frame with a printer. ### Claim 45 An image processing method comprising the steps of: converting an original image into a set of vector line segments having initial and terminal points corresponding to characteristic points comprising end points, contact points, intersections, and branching points; extracting vectors defining a rectangle on the basis of a connecting relationship between vector line segments belonging to the set of vector line segments, wherein said rectangle extracting step comprises the steps of: retrieving a horizontal or vertical vector from the vector line segments; and tracing a vertical or horizontal vector connected to the horizontal or vertical vector retrieved in said vector retrieving step, thereby extracting the vectors defining the rectangle; and performing an operation on numerical information within each rectangle extracted in said rectangle extracting step in accordance with the position of each rectangle. ### Claim 46 (depends on 45) A method according to claim 45, further comprising the step of inputting the original image with a scanner. ### Claim 47 (depends on 45) A method according to claim 45, further comprising the step of instructing the inputting of the original image with a keyboard. ### Claim 48 (depends on 45) A method according to claim 45, further comprising the step of making a frame in accordance with the extracted rectangle. ### Claim 49 (depends on 48) A method according to claim 48, further comprising the step of displaying the frame with a cathode ray tube. ### Claim 50 (depends on 48) A method according to claim 48, further comprising the step of printing the frame with a printer. ### Claim 51 (depends on 45) A method according to claim 45, wherein said rectangular extracting step further comprises the step of extracting a tilted line. ### Claim 52 An image processing method comprising the steps of: extracting from an original image a plurality of line segments including characteristic points; selecting line segments connected to one of the plurality of extracted characteristic points; classifying the line segments selected in said line segments selecting step in accordance with angles between the selected line segments; storing classification results of said classifying step with the respective extracted line segments; making a frame in accordance with the stored classification result; and performing an operation on numerical information within the frame made in said frame making step. ### Claim 53 (depends on 52) A method according to claim 52, wherein said classifying step classifies the line segments into parallel lines and tilted lines. ### Claim 54 (depends on 52) A method according to claim 52, wherein the one of the plurality of characteristic points is a bent point. ### Claim 55 (depends on 52) A method according to claim 52, wherein the one of the plurality of characteristic points is an intersection point. ### Claim 56 (depends on 52) A method according to claim 52, wherein the one of the plurality of characteristic points is a branching point. ### Claim 57 (depends on 52) A method according to claim 52, further comprising the step of inputting the original image with a scanner. ### Claim 58 (depends on 52) A method according to claim 52, further comprising the step of instructing the inputting of the original image with a keyboard. ### Claim 59 (depends on 52) A method according to claim 52, further comprising the step of displaying the frame with a cathode ray tube. ### Claim 60 (depends on 59) A method according to claim 59, further comprising the step of printing the frame with a printer. ### Claim 61 An image processing method comprising the steps of: extracting from an original image a plurality of line segments including characteristic points; selecting line segments connected to one of the plurality of extracted characteristic points; classifying the line segments selected in said line segments selecting step in accordance with lengths of the selected line segments; storing classification results of said classifying step with the respective extracted line segments; making a frame in accordance with the stored classification result; and performing an operation on numerical information within the frame made in said frame making step. ### Claim 62 (depends on 61) A method according to claim 61, wherein said classifying step classifies the line segments into parallel lines and tilted lines. ### Claim 63 (depends on 63) A method apparatus according to claim 63, wherein the one of the plurality of characteristic points is a bent point. ### Claim 64 (depends on 61) A method according to claim 61, wherein the one or the plurality of characteristic points is an intersection point. ### Claim 65 (depends on 61) A method according to claim 61, wherein the one of the plurality of characteristic points is a branching point. ### Claim 66 (depends on 61) A method according to claim 61, further comprising the step of inputting the original image with a scanner. ### Claim 67 (depends on 61) A method according to claim 61, further comprising the step of instructing the inputting of the original image with a keyboard. ### Claim 68 (depends on 61) A method according to claim 61, further comprising the step of displaying the frame with a cathode ray tube. ### Claim 69 (depends on 61) A method according to claim 61, further comprising the step of printing the frame with a printer. ### Claim 70 An image processing method comprising the steps of: converting an original image into a plurality of vector line segments; storing characteristic points including an initial point and a terminal point of each vector line segment converted in said vector forming step; extracting vectors defining a rectangle on the basis of a connecting relationship between vector line segments belonging to the stored vector line segments, wherein said rectangle extracting step comprises the steps of: retrieving a horizontal or vertical vector from the vector line segments; tracing a vector having the same point data as the characteristic points of the retrieved vector, thereby extracting the vectors defining the rectangle; and performing an operation on numerical information within each rectangle extracted in said rectangle extracting step in accordance with the position of each rectangle. ### Claim 71 (depends on 70) A method according to claim 70, further comprising the step of making a frame in accordance with the extracted rectangle. ### Claim 72 (depends on 70) A method according to claim 70, wherein the one of the plurality of characteristic points is a bent point. ### Claim 73 (depends on 70) A method according to claim 70, wherein the one of the plurality of characteristic points is an intersection point. ### Claim 74 (depends on 70) A method according to claim 70, wherein the one of the plurality of characteristic points is a branching point. ### Claim 75 (depends on 70) A method according to claim 70, further comprising the step of inputting the original image with a scanner. ### Claim 76 (depends on 70) A method according to claim 70, further comprising the step of instructing the inputting of the original image with a keyboard. ### Claim 77 (depends on 71) A method according to claim 71, further comprising the step of displaying the frame with a cathode ray tube. ### Claim 78 (depends on 71) A method according to claim 71, further comprising the step of printing the frame with a printer.