Machine learning: IOU of concept understanding

IoU(Intersection over Union)： Occurring simultaneously than , stay SSD In my paper, it is also called Jaccard Overlap, It means the same thing . Literally, it is the ratio of intersection and union .

The calculation method is shown in the figure below ：

IoU Calculate in the target detection algorithm mAP Important functions of , By calculating the predicted value and the true value box IoU, And compare with a threshold to determine the correctness of the prediction frame .
As shown in the two boxes in the following figure IoU It's worth a lot , You will get good test results