Some questions about image augmentation

[ws6125]

Hello, I'm a newbie of image captioning. I have some questions about the image augmentation in coco.py.

1. Flip and rotate will make the wrong position, such as "left & right" and "above & under", I think those augmentations are not good with image captioning. Could you please tell me why using flip and rotate?
2. Why the numerical ranges of brightness, contrast, and saturation in color jitter are [0.5, 1.3], [0.8, 1.5], and [0.2, 1.5]? Do you reference other works or papers? If yes, could you please tell me the reference?

Thank you.