I tried RectLabel, it's working well, you can export in the correct format. https://apps.apple.com/fr/app/rectlabel/id1210181730?mt=12

Hi, I'm share my improvements. I've added some training data from a set found on the internet with very different colors and sizes. The results are better now, but not as I expect : Weird result : Good but incomplete Nothing : Good & bad :) Stats

Hi ! Thanks for your answer. Indeed, on some dice I've rotate the bounding box in the RectLabel app, but after exporting, the rotation is removed : { "image": "IMG_5653.HEIC", "annotations": [ { "label": "1", "coordinates": { "y": 2103, "x": 1571, "width": 952, "height": 962 } } ] }, Here is on the left, the real generated bounding box and on the right the visualization in RectLabel, so the boundingbox looks fine. but if you are using an annotation format that anchors to the upper left of the bounding boxes and the app is expecting the center of the bounding box, your model is going to be training on different areas than you expect. I'm not sure what is my anchor point with the above code. For now I don't have any app, I'm just trying to train the model. What's the next step ? Should I add more images for the training ? There is a "transfert learning" option, should I use it ? Actually I tried this option, the loss is very low (0.01) but the actual detection is not better.