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KI-Atlas

Objekterkennung

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Der vollständige Artikel liegt auf Englisch vor; Titel und Zusammenfassung sind lokalisiert.

WAS DIESE FÄHIGKEIT BEDEUTET

Takes an image and outputs a set of bounding boxes, each with a class label and a confidence score. Unlike classification it is not content with one label for the whole image but must say what is where; unlike segmentation it gives rectangles rather than pixel-accurate outlines. Several instances of the same class can be detected at once.

Wie sie technisch umgesetzt wird

The mainstream is single-stage detection: anchors or centre points are densely predicted on a feature map and one forward pass regresses both box location and class at once, the YOLO line and SSD being the classic examples, fast enough for real time. Two-stage detectors first propose regions then classify each, slightly more accurate but slower. The loss optimises localisation and classification together, and non-maximum suppression merges overlapping boxes at the end.

Repräsentative Produkte

4

Beteiligte Organisationen

Typische Verwendungen

  • Vehicle and pedestrian perception for driving
  • Video surveillance and perimeter alerts
  • Shelf and inventory counting in retail
  • Object surveys in remote-sensing imagery

Wie sie bewertet wird

mAP
Mean of per-class average precision, usually at an IoU threshold
IoU
Intersection over union between predicted and true boxes, the hit criterion
Inference speed (FPS)
As important as accuracy in real-time settings

Grenzen und schwierige Punkte

  • Recall drops sharply for occluded, truncated and very small objects
  • In crowded scenes non-maximum suppression wrongly removes neighbours; two people side by side may become one
  • Objects outside the trained classes are either missed or forced into the nearest known class

Konzepte dahinter