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This article mainly introduces how to use python to calculate polygon IoU in 2D, the content is detailed and easy to understand, the operation is simple and fast, and it has a certain reference value. I believe you will get something after reading this article on how to use python to calculate polygon IoU in 2D. Let's take a look.

Suppose the points of each polygon are arranged clockwise in a circle. If we find that the signature area is negative, we can ensure this by increasing the angle w.r.t x-axis or reversing point.

Merge the points of two polygons into a single list to track which polygon each point belongs to. We also need to be able to determine the upper and next points of each point in the original polygon. L

Sort the w.r.t x axis by increasing the angle. L

If the input polygons intersect, the number of transitions from one polygon to another polygon will be greater than two. L

Traversing. If a continuous point belongs to a different polygon, the intersection of the line between the first point and its next point and the second point and its previous point will belong to the intersection between the two polygons. L

Add each point identified in step 4 to the new polygon. The integrals will be encountered sequentially. II

The sum of the area of each polygon will be equal to its alliance plus the area of the intersection, because this will be calculated twice.

Therefore, the value is represented by the sum of the areas of the two polygons minus the sum of the areas. IoUII

The only geometry required is to use the Shoelace formula to calculate the area of a simple polygon and to determine the point of intersection between the two segments required in step 5.

Here is some Java code (Ideone) to illustrate-you may be able to make it more compact in Python.

Double [] [] coords = {{- 0.708, 0.707, 0.309,-0.951, 0.587,-0.809}, {1, 0, 0, 1,-1, 0, 0,-1, 0.708,-0.708}}; double areaSum = 0 position list pts = new ArrayList (); for (int list 0; p

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