Detectron: I meet this question:“not enough values to unpack (expected 3, got 2)”?

[qiguming]

File "/home/qifengliang/detectron/detectron/utils/vis.py", line 332, in vis_one_image
e.copy(), cv2.RETR_CCOMP, cv2.CHAIN_APPROX_NONE)
ValueError: not enough values to unpack (expected 3, got 2)

[ChuhuaW]

I have encountered the same issue when running:
python tools/infer_simple.py \ --cfg configs/12_2017_baselines/e2e_mask_rcnn_R-101-FPN_2x.yaml \ --output-dir /tmp/detectron-visualizations \ --image-ext jpg \ --wts https://dl.fbaipublicfiles.com/detectron/35861858/12_2017_baselines/e2e_mask_rcnn_R-101-FPN_2x.yaml.02_32_51.SgT4y1cO/output/train/coco_2014_train:coco_2014_valminusminival/generalized_rcnn/model_final.pkl \ demo
According to https://stackoverflow.com/questions/54164630/want-to-find-contours-valueerror-not-enough-values-to-unpack-expected-3-go, the cv2.findContours() has changed.
Go to /detectron/detectron/utils/vis.py in line 331, change it into:
contour, hier = cv2.findContours( e.copy(), cv2.RETR_CCOMP, cv2.CHAIN_APPROX_NONE)
My problem solved.

[ling-cv]

Opencv change returns of function cv2.findContours from image, contour, hier (since 3.2.0) to contour, hier, in the latest 4.0.0 version

[qiguming]

Opencv change returns of function cv2.findContours from image, contour, hier (since 3.2.0) to contour, hier, in the latest 4.0.0 version

Thank you, I have solved this problem after I changed the version of cv2.

[ir413]

Hi all, please see my comment in #809.