Dimension mismatch in box_coder.py

[chrisliu54]

torchcv/torchcv/models/ssd/box_coder.py

Line 119 in 2ee9c46

box = box_preds[mask.nonzero().squeeze()]

In normal cases, mask.nonzero().squeeze() squeezes out the non zero terms in mask, which makes box is of the same shape as box_preds(2d tensor).
However, when there is only one True element in mask, box turns out to be a 1d tensor, which leads to dimension mismatch error in the lines below.

torchcv/torchcv/utils/box.py

Lines 102 to 105 in 6291f3e

	x1 = bboxes[:,0]
	y1 = bboxes[:,1]
	x2 = bboxes[:,2]
	y2 = bboxes[:,3]

I suggest to modify the mask operation like this below:

box = box_preds[mask]