position, colour, and background colour of text labels in draw_bounding_boxes

🚀 The feature

Text labels from torchvision.utils.draw_bounding_boxes are currently always inside the box with origin at the top left corner of the box, without a background colour, and the same colour as the bounding box itself. These are three things that would be nice to control.

Motivation, pitch

The problem with the current implementation is that it makes it hard to read the label, particularly when the bounding box is filled (because the text has the same colour as the filling colour and is placed inside the box.

For example, this is the results from the current implementation:

Moving the label to outside the box already makes things better:

But by controlling those three things (placement of label, background colour behind the label, and text colour) one could fit to whatever they have. For what is worth, in the original issue for this feature, the only example image had labels outside the box, text coloured different from the box (black), and background of the same colour as the box. See https://github.com/pytorch/vision/issues/2556#issuecomment-671344086

I'm happy to contribute this but want to know if this will be accepted and with what interface.

Start with the torchvision.utils.draw_bounding_boxes entry point and review the related discussion in issue 2556. Confirm the accepted interface with maintainers for label placement, text colour, and background colour; done means all three aspects are controllable without harming existing usage.