Thanks for your answer.
I have another question.
I see the following lines of code of faster-rcnn in torchvision:

anchor_sizes = ((32,), (64,), (128,), (256,), (512,))
aspect_ratios = ((0.5, 1.0, 2.0),) * len(anchor_sizes)

I’m trying to detect manufacter logos/text labels.
They always have small enough size.
Does it mean that I should try to decrease my the rpn anchor_sizes for that case ( since at the moment I also have a problem finding small size bounding boxes) or this settings shouldn’t be changed?