CenterNet2 Xingyi Zhou, Vladlen Koltun, Philipp Krhenbhl UT Austin - - PowerPoint PPT Presentation

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CenterNet2 Xingyi Zhou, Vladlen Koltun, Philipp Krhenbhl UT Austin - - PowerPoint PPT Presentation

CenterNet2 Xingyi Zhou, Vladlen Koltun, Philipp Krhenbhl UT Austin & Intel Labs 1 Conventional two-stage detector Backbone Classifier BB regression ROIAlign Stage 1 Stage 2 45ms 8ms Ren et. al, Faster R-CNN: Towards


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CenterNet2

Xingyi Zhou, Vladlen Koltun, Philipp Krähenbühl UT Austin & Intel Labs

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Conventional two-stage detector

Backbone

Classifier BB regression

ROIAlign

Stage 1 45ms Stage 2 8ms

Ren et. al, Faster R-CNN: Towards Real-Time Object Detection with Region Proposal Networks, NIPS 2015

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Cascade detector

Backbone

Classifier BB regression

ROIAlign

Stage 1 45ms Stage 2 8ms Stage 3 8ms

ROIAlign …

Classifier BB regression

… … Cai et. al, Cascade R-CNN: Delving into High Quality Object Detection, CVPR 2018

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One-stage detector

Backbone Classifier BB regression Stage 1 53ms

Lin et. al, Focal Loss for Dense Object Detection, ICCV 2017

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CenterNet

Backbone keypoint detection size regression Stage 1 53ms

Zhou et. al, Objects as Points, arXiv 2019

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CenterNet2

Backbone keypoint detection size regression Stage 1 51ms

Classifier BB regression

ROIAlign

Stage 2 2ms Stage 3 2ms

… ROIAlign

Classifier BB regression

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Results

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COCO box mAP

38 39.75 41.5 43.25 45 CenterNet-FPN CascadeRCNN CenterNet2

42.9 42.1 39.6 COCO runtime (ms)

20 40 60 80 CenterNet-FPN CascadeRCNN CenterNet2

60 70 53 LVIS box mAP

20 22.5 25 27.5 30 CascadeRCNN CenterNet2

26.9 24

  • Res50, Multi-scale, 1x
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Federated datasets

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… Negatives Positives … Unlabeled …

Gupta et. al, LVIS: A Dataset for Large Vocabulary Instance Segmentation, CVPR 2019

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Cross entropy

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… Positives … … Negatives

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Equalization loss (Tan et al. 2020)

  • For frequent classes
  • Sigmoid cross entropy
  • For rare classes
  • Ignore negative loss from

foreground

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Tan et. al, Equalization Loss for Long-Tailed Object Recognition CVPR 2020

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Federated Loss (ours)

  • Positive classes
  • Sigmoid cross entropy
  • Negative or unlabeled classes
  • Sampled to apply negative

loss

  • Sample based on frequency

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Results

7 14 21 28 35 Box AP Box APr Box APc Box APf

33.3 26 16.1 27.1 31.5 24.6 15.5 25.7 31.5 21.9 8.2 23.3 32.7 22.9 7.6 24

Softmax-CE Sigmoid-CE EQL FedLoss

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Challenge model

mAP 24 28 32 36 40 CenterNet2 +Mask +2x +FPN2-6 +X101 +DCN +PointRend +Larger input +Test-aug

27.2 36.1 34.9 34 32.1 30.3 28.2 27.4 25.3 38.5 37.3 36.7 35.9 33.9 31.5 30.6 28.6 28.2

Box mAP Mask mAP Official baseline

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Thanks!