Machine vision system and method for analyzing illumination lines in an image to determine characteristics of an object being inspected

A method for tracing a line in an image, wherein the line is displayed on a surface of an object in the image, wherein the tracing is performed to identify defects in the object, wherein the line includes a left edge and a right edge, the method comprising:

• projecting a pattern of lines on a surface of the object;
• generating an image of the surface of the object, wherein the image includes the pattern of lines projected on the surface of the object, wherein each line includes a left edge and right edge;
• a) determining left and right edge points of a line in the image;
• b) determining a local width of the line for the left and right edge points of the line;
• c) determining a local orientation of the first line for the left and right edge points of the line;
• repeating (a)-(c) a plurality of times to substantially trace the line and determine information regarding the line;
• determining whether a defect is present in the object using said local widths and said local orientations.

A method for analyzing an image of an object to identify defects in the object, the method comprising:

• projecting a pattern of lines on a surface of the object;
• generating an image of the surface of the object, wherein the image includes the pattern of lines projected on the surface of the object, wherein each line includes a left edge and right edge;
• for each respective line of a plurality of the lines, tracking left and right edges of the respective line in the image;
• determining whether a defect is present in the object using said left and right edge points of the plurality of the lines.

A method for tracing a line in an image, wherein the line is displayed on a surface of an object in the image, wherein the tracing is performed to identify defects in the object, wherein the line includes a left edge and a right edge, the method comprising:

• projecting a pattern of lines on a surface of the object;
• generating an image of the surface of the object, wherein the image includes the pattern of lines projected on the surface of the object, wherein each line includes a left edge and right edge;
• a) tracking left and right edges of the line in the image;
• b) determining a local width of the line for the left and right edge points of the line;
• c) determining a local orientation of the first line for the left and right edge points of the line;
• repeating steps (a)-(c) a plurality of times to substantially trace the line and determine information regarding the line;
• determining whether a defect is present in the object using said local widths and said local orientations.

A memory medium comprising program instructions for tracing a line in an image, wherein the line is displayed on a surface of an object in the image, wherein the tracing is performed to identify defects in the object, wherein the line includes a left edge and a right edge, wherein the program instructions are executable to implement:

• projecting a pattern of lines on a surface of the object;
• generating an image of the surface of the object, wherein the image includes the pattern of lines projected on the surface of the object, wherein each line includes a left edge and right edge;
• a) tracking left and right edges of the line in the image, wherein said tracking includes determining left and right edge points of the line;
• b) determining a local width of the line from the left and right edge points of the line;
• c) determining a local orientation of the first line for the left and right edge points of the line;
• repeating steps (a)-(c) a plurality of times to substantially trace the line and determine information regarding the line;
• determining whether a defect is present in the object using said local widths and said local orientations.

A machine vision system for analyzing an image of an object to identify defects in the object, the system comprising:

• a light source configured to project a pattern of lines on a surface of the object;
• a camera adapted to produce an image of the object, wherein the image includes the pattern of lines projected on the surface of the object, wherein each line includes a left edge and right edge;
• a computer system coupled to the camera and adapted to receive the image of the object, wherein the computer system includes a memory medium and a processor, wherein the memory medium stores a line analysis software program, wherein, for each line of at least a subset of the pattern of lines, the processor is operable to execute the line analysis software program to:
• a) determine left and right edge points of the line in the image;
• b) determine a local width of the line from the left and right edge points of the line;
• c) determine a local orientation of the first line for the left and right edge points of the line;
• repeat (a)-(c) a plurality of times to substantially trace the line and determine information regarding the line;
• and
• determine whether a defect is present in the object using said local widths and said local orientations.

A memory medium comprising program instructions for analyzing an image of an object to identify defects in the object,

• wherein a pattern of lines is operable to be projected on a surface of the object;
• and
• wherein an image of the surface of the object is operable to be generated, wherein the image includes the pattern of lines projected on the surface of the object, wherein each line includes a left edge and right edge;
• wherein the program instructions are executable to implement:
• for each respective line of a plurality of the lines, repeatedly determining left and right edge points of the respective line in the image, wherein said repeatedly determining operates to trace at least a portion of the respective line in the image;
• determining a local width of the respective line for at least a subset of the left and right edge points of the respective line;
• determining if at least one of a thinning or blooming of the respective line occurs which exceeds a threshold, wherein said determining if at least one of a thinning or blooming of the respective line occurs is based on one or more of the local widths of the respective line;
• wherein at least one of a determined thinning or blooming of the respective line which exceeds the threshold indicates a possible defect in the object.

A method for analyzing an image of an object to identify defects in the object, the method comprising:

• projecting a pattern of lines on a surface of the object;
• generating an image of the surface of the object, wherein the image includes the pattern of lines projected on the surface of the object, wherein each line includes a left edge and right edge;
• for each respective line of a plurality of the lines, repeatedly determining left and right edge points of the respective line in the image, wherein said repeatedly determining operates to trace at least a portion of the respective line in the image;
• determining a local width of the respective line for at least a subset of the left and right edge points of the respective line;
• and
• determining if a thinning of the respective line occurs which exceeds a threshold, wherein said determining if a thinning of the respective line occurs is based on one or more of the local widths of the respective line;
• wherein a determined thinning of the respective line which exceeds the threshold indicates a possible defect in the object.

A method for analyzing an image of an object to identify defects in the object, the method comprising:

• projecting a pattern of lines on a surface of the object;
• generating an image of the surface of the object, wherein the image includes the pattern of lines projected on the surface of the object, wherein each line includes a left edge and right edge;
• for each respective line of a plurality of the lines, repeatedly determining left and right edge points of the respective line in the image, wherein said repeatedly determining operates to trace at least a portion of the respective line in the image;
• determining a local width of the respective line for at least a subset of the left and right edge points of the respective line;
• and
• determining if a blooming of the respective line occurs which exceeds a threshold, wherein said determining if a blooming of the respective line occurs is based on one or more of the local widths of the respective line;
• wherein a determined blooming of the respective line which exceeds the threshold indicates a possible defect in the object.

A method for analyzing an image of an object to identify defects in the object, the method comprising:

• projecting a pattern of lines on a surface of the object;
• generating an image of the surface of the object, wherein the image includes the pattern of lines projected on the surface of the object, wherein each line includes a left edge and right edge;
• for each respective line of a plurality of the lines, repeatedly determining left and right edge points of the respective line in the image, wherein said repeatedly determining operates to trace at least a portion of the respective line in the image, wherein said repeatedly determining comprises:
• repeatedly determining left and right edge points of the respective line in the image in an upward path from at least one point in the respective line;
• repeatedly determining left and right edge points of the respective line in the image in a downward path from the at least one point;
• determining whether a defect is present in the object using said left and right edge points of the plurality of the lines.

A method for analyzing an image of an object to identify defects in the object, the method comprising:

• projecting a pattern of lines on a surface of the object;
• generating an image of the surface of the object, wherein the image includes the pattern of lines projected on the surface of the object, wherein each line includes a left edge and right edge;
• for each respective line of a plurality of the lines, repeatedly determining left and right edge points of the respective line in the image, wherein said repeatedly determining operates to trace at least a portion of the respective line in the image, wherein said repeatedly determining left and right edge points of the respective line in the image comprises:
• at a first point in the image, determining if the first point lies within the respective line;
• if the first point lies within the respective line, then performing an edge detection in a first direction away from the first point and parallel to an orientation of the respective line to determine a first edge of the respective line;
• if the first point lies outside of the respective line, then performing an edge detection in a second direction away from the first point and parallel to an orientation of the respective line to determine a second edge of the respective line, wherein the second direction is opposite of the first direction;
• and
• determining whether a defect is present in the object using said left and right edge points of the plurality of the lines.

A method for analyzing an image of an object to identify defects in the object, the method comprising:

• projecting a pattern of lines on a surface of the object;
• generating an image of the surface of the object, wherein the image includes the pattern of lines projected on the surface of the object, wherein each line includes a left edge and right edge;
• for each respective line of a plurality of the lines, repeatedly determining left and right edge points of the respective line in the image, wherein said repeatedly determining operates to trace at least a portion of the respective line in the image, wherein said repeatedly determining left and right edge points of the respective line in the image comprises:
• at a first point in the image, determining if the first point lies within the respective line;
• if the first point lies within the respective line, then:
• performing an edge detection in a first direction away from the first point and parallel to an orientation of the respective line to determine a first edge of the respective line;
• and
• performing an edge detection in a second direction away from the first edge and parallel to an orientation of the respective line to determine a second edge of the respective line, wherein the second direction is opposite of the first direction;
• if the first point lies outside of the respective line, then:
• performing an edge detection in the second direction away from the first point and parallel to an orientation of the respective line to determine the second edge of the respective line;
• and
• performing an edge detection in the first direction away from the second edge and parallel to an orientation of the respective line to determine the first edge of the respective line;
• and
• determining whether a defect is present in the object using said left and right edge points of the plurality of the lines.

A method for analyzing an image of an object to identify defects in the object, the method comprising:

• projecting a pattern of lines on a surface of the object;
• generating an image of the surface of the object, wherein the image includes the pattern of lines projected on the surface of the object, wherein each line includes a left edge and right edge;
• for each respective line of a plurality of the lines, repeatedly determining left and right edge points of the respective line in the image, wherein said repeatedly determining operates to trace at least a portion of the respective line in the image, wherein said repeatedly determining comprises:
• determining if two or more lines overlap;
• detecting when the two or more lines cease overlapping;
• and
• continuing said repeatedly determining after the two or more lines cease overlapping;
• determining whether a defect is present in the object using said left and right edge points of the plurality of the lines.