Function approximation processing method and image processing method
First Claim
Patent Images
1. A function approximation processing method comprising:
- performing by a processor the following steps;
an input step of inputting image data;
a binarization step of binarizing the input image data;
a contour extraction step of extracting line segments of horizontal and vertical directions from the binarized image data;
a tangent line segment extraction step of extracting, as a tangent line segment, a line segment that has a length satisfying predetermined conditions from the extracted line segments of horizontal and vertical directions;
an anchor point extraction step of extracting, as an anchor point, a point on the extracted tangent line segment, wherein the anchor point is an endpoint on the extracted tangent line segment in a case where a line segment adjacent to the extracted tangent line segment is a tangent line segment, or the anchor point is a point that corresponds to an end point on the extracted tangent line segment that is shifted, in a case where the line segment adjacent to the extracted tangent line segment is not a tangent line segment;
a curve approximation processing step of performing curve approximation processing in which a line segment between anchor points that are respectively extracted in the anchor point extraction step is approximated to a curve; and
a correction step of replacing the curve approximated in the curve approximation processing step with a diagonal straight line in a case where the line segment approximated in the curve approximation processing step was originally a diagonal straight line.
1 Assignment
0 Petitions
Accused Products
Abstract
A function approximation processing method comprises inputting and binarizing image data, extracting contour from the binarized image data, estimating tangent points in horizontal and vertical directions from the contour, and approximating contour between adjacent tangent points among the estimated tangent points with a predetermined function, thereby an input object such as a character or a figure can be processed at high speed, and outline data with high image quality can be generated with a reduced number of points.
16 Citations
10 Claims
-
1. A function approximation processing method comprising:
-
performing by a processor the following steps; an input step of inputting image data; a binarization step of binarizing the input image data; a contour extraction step of extracting line segments of horizontal and vertical directions from the binarized image data; a tangent line segment extraction step of extracting, as a tangent line segment, a line segment that has a length satisfying predetermined conditions from the extracted line segments of horizontal and vertical directions; an anchor point extraction step of extracting, as an anchor point, a point on the extracted tangent line segment, wherein the anchor point is an endpoint on the extracted tangent line segment in a case where a line segment adjacent to the extracted tangent line segment is a tangent line segment, or the anchor point is a point that corresponds to an end point on the extracted tangent line segment that is shifted, in a case where the line segment adjacent to the extracted tangent line segment is not a tangent line segment; a curve approximation processing step of performing curve approximation processing in which a line segment between anchor points that are respectively extracted in the anchor point extraction step is approximated to a curve; and a correction step of replacing the curve approximated in the curve approximation processing step with a diagonal straight line in a case where the line segment approximated in the curve approximation processing step was originally a diagonal straight line. - View Dependent Claims (2, 3, 4, 5, 6, 7, 9, 10)
-
-
8. A function approximation processing apparatus comprising:
-
input means for inputting image data; binarization means for binarizing the input image data; contour extraction means for extracting line segments of horizontal and vertical directions from the binarized image data; tangent line segment extraction means for extracting, as a tangent line segment, a line segment that has a length satisfying predetermined conditions from the extracted line segments of horizontal and vertical directions; anchor point extraction means for extracting, as an anchor point, a point on the extracted tangent line segment, wherein the anchor point is an end point on the extracted tangent line segment in a case where a line segment adjacent to the extracted tangent line segment is a tangent line segment, or the anchor point is a point that corresponds to an end point on the extracted tangent line segment that is shifted, in a case where the line segment adjacent to the extracted tangent line segment is not a tangent line segment; curve approximation processing means for performing curve approximation processing in which a line segment between anchor points that are respectively extracted in the anchor point extraction step is approximated to a curve; and correction means for replacing the curve approximated in the curve approximation processing step with a diagonal straight line in a case where the line segment approximated in the curve approximation processing step was originally a diagonal straight line.
-
Specification