Interpretation of yolov3 key code

Before reading this article , Sort it out first VOC2007 How data is converted into yolo Data needed

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One . from loss set out ,tragets How to calculate it

Deduce ： When it comes to implementing this part , What does the iteratable object do internally

pbar = tqdm(enumerate(dataloader), total=nb)
for i, (imgs, targets, paths, _) in pbar:

Enter into dataset Object implemented __getitem__() Method （ The basis of python grammar ）

While reading the code , Find out yolov3, Adopted resize The picture strategy is , Start with the long side resize, Then fill up the short edge , Avoid image deformation .

Why are there mosaics