| 摘要 |
The disclosure provides an image processing device, image processing method, scanner and storage medium. The image processing device is used for tracing a boundary of an object image in an image, the boundary being continuous and the rate of change in slope between adjacent points on the boundary being slow. The image processing device includes: a boundary estimation unit, adapted to estimate the location of the boundary of the object image; an interfering gradient processing unit, adapted to process an interfering gradient near the estimated boundary, so as to reduce the interfering gradient or remove the interfering gradient from the image; and a boundary tracing unit, adapted to trace the boundary in the image having the interfering gradient processed. By using the technique of the disclosure, the accuracy of tracing a boundary of an image is improved significantly. |
| 主权项 |
1. An image processing device for tracing a boundary of an object image in an image, the boundary being continuous and the rate of change in slope between adjacent points on the boundary being slow, the image processing device comprising:
a boundary estimation unit, adapted to estimate the location of the boundary of the object image; an interfering gradient processing unit, adapted to process an interfering gradient near the estimated boundary, so as to reduce the interfering gradient or remove the interfering gradient from the image; and a boundary tracing unit, adapted to trace the boundary in the image having the interfering gradient processed; wherein the boundary estimation unit comprises: a segmentation unit, adapted to segment a portion of the image between two corners on the boundary into a predetermined number of segments; a segment boundary estimation unit, adapted to estimate the location of the boundary respectively in each of the segments; wherein the segment boundary estimation unit comprises a boundary approximation unit for approximating the boundary in each of the segments using a straight line segment, wherein the boundary approximation unit is adapted to, for at least one of outermost segments where the corners are in respectively, set the corner in the outermost segment as a start point of a first straight line segment used to approximate the boundary in the outermost segment, and select an end point for the first straight line segment on a first segmentation line resulting in the outermost segment, so that in a gradient histogram of a narrow band covering the first straight line segment, pixels exhibit the greatest degree of concentration with respect to the greatest gradient; and the boundary approximation unit is further adapted to set the obtained end point of the boundary-approximating straight line segment as a start point of a second straight line segment used to approximate the boundary in a next, adjacent segment, and select an end point for the second straight line segment on a second segmentation line which results in the next segment and is not common to the next segment and the segment for which the boundary-approximating straight line segment has been obtained, so that in a gradient histogram of a narrow band covering the second straight line segment, pixels exhibit the greatest degree of concentration with respect to the greatest gradient. |
