Polyline Annotation Case Study

General Rules for Drawing Lines
1. The line needs to be drawn in the center of the lane line, with left and right excursion of no more than 2px. Deformation caused by uneven road surfaces also needs to be labeled in the center of the line.
2. The curb is labeled near the middle edge, that is, the lower edge of the labeled curb.
3. The line needs to be close to where the current car is, far away to where it can be seen, and the line needs to pass through the occlusions. But the imagination or extension length cannot exceed the visible length.
4. When the visible part of the lane line is smaller than the diameter of the circular ruler, the lane line does not need to be labeled.
5. When the dashed part of the lane line is smaller than the diameter of the inner circle of the ruler, the dashed end of the line does not need to be labeled.
6. All lines in the field of view should be labeled.