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Polyline Annotation Case Study

There are signs on the road surface in a driving area that uses lines, arrows, text, elevation signs, bump signs, and contour signs to convey guidance, restrictions, warnings, and other traffic information. Their role is to control and direct traffic.

Next, we’d like to share a lane annotation case study.

Actually, lanes are labeled with point sets, that is, each example of a lane line is represented as a set of points. The pixel and precision requirements of the annotated image are relatively high.

  1. Each lane line

(1) Outer contour

Closed form. If there is an occluded part in the middle, it is necessary to imagine and complete it.

(2) Categories

a) Lane line type

b) Color

c) Whether it is occluded

d) Whether it can be crossed

(1) Lane line type:

Classify the type based on whether it is solid or dashed, such as:

  • Solid line
  • Dashed line
  • Solid-solid lines
  • Dashed-dashed lines
  • Solid-dashed lines
  • Dashed-solid lines
  • Dashed-dashed-dashed lines
  • Others

(2) Color:

Name by color, such as:

  • White
  • Yellow
  • White-yellow
  • White-white
  • Others

(3) Occlusion:

  • True: The outer contour is occluded
  • False: The outer contour is not occluded

(4) Cross over:

  • Left: can be passed from the left
  • Right: can be crossed from the right
  • Both: can be crossed from both sides
  • False: cannot be crossed

(1) Double or triple lines are labeled together

(2) Y or V shape into three or two

(3) The start point is from the position of the ego vehicle or the bottom boundary of the image

(4) The endpoint extends to the furthest lane that can be seen.

(5) Label two lines with different shapes

(1) Weather

(2) Road condition

(3) Time


(1) Image standard

No missed line, no mislabeled line, no extra line.

(2) Line standard

The line should be drawn in the center, with pixel error within 2px.

(3) All attributes should be chosen correctly.

Only Three Steps to go

  • Log in with your email
  • Upload the sample
  • Tell us what to label: tell us the minimum labeling size and the precision you need.

You can send the requirement to us, and we will handle the configuration job.

Then it’s our turn.

Demo and quote would be ready in less than 24h on weekdays.


ByteBridge Lane Annotation

JSON Output

ByteBridge Lane Annotation JSON

Outsource your data labeling tasks to ByteBridge, you can get high-quality ML training datasets cheaper and faster!

  • Free Trial Without Credit Card: you can get your sample result in a fast turnaround, check the output, and give feedback directly to our project manager.
  • 100% Human Validated
  • Transparent & Standard Pricing: clear pricing is available(labor cost included)



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