Closed remtav closed 3 years ago
That's true for satellite imagery. But since brightness and contrast shifts are only histograms modifications, there are a few considerations:
It's worth the discussion, tough. I think the first step would be to test the first hypothesis and work from there. I'll add this to our "tests wishlist".
Math
Augmentration techniques should be reviewed (noise, blur, geometric scaling, etc.). Overall, there could be a slight improvement of results if different augmentation strategies were tested. For example, test-time augmentation could be interesting to try out.
This paper deserves a look: https://link.springer.com/article/10.1186/s40537-019-0197-0
Edited June 25th 2020: Mathieu, the point you raised is important to keep in mind. Currently random radiometric trim augmentation is applied to all bands at once. We'll have to think at how it could be applied to only a portion of those bands. First, I imagine we'd have to inform GDL what bands it will be seeing by their name in what order (e.g. RGB, not band 012 or 123), then identify which bands will need to be augmented. To be discussed.
This implementation good be a good start: https://github.com/SpaceNetChallenge/SpaceNet_SAR_Buildings_Solutions/blob/master/2-MaksimovKA/predict/tta.py
Wouldn't trained models gain robustness if data augmentations (utils/augmentation.py) included brightness and contrast shifts (ex.: random, 10-15%)? I imagine it could also help with overfitting issues.