label format

[xiyufeng2]

    Box coordinates are in normalized xywh format (from 0 - 1). If your boxes are in pixels, divide x_center and w by image width, and y_center and h by image height.
    The image height here refers to the original size of the image or the resized size 416？？thank you！

[github-actions]

👋 Hello @xiyufeng2, thank you for your interest in 🚀 YOLOv5! Please visit our ⭐️ Tutorials to get started, where you can find quickstart guides for simple tasks like Custom Data Training all the way to advanced concepts like Hyperparameter Evolution.

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[glenn-jocher]

@xiyufeng2 to normalize labels you would simply divide the existing coordinate system by its max value. The tutorial shows an example:
https://docs.ultralytics.com/yolov5/tutorials/train_custom_data/_edit

2. Create Labels

After using a tool like CVAT, makesense.ai or Labelbox to label your images, export your labels to YOLO format, with one *.txt file per image (if no objects in image, no *.txt file is required). The *.txt file specifications are:

• One row per object
• Each row is class x_center y_center width height format.
• Box coordinates must be in normalized xywh format (from 0 - 1). If your boxes are in pixels, divide x_center and width by image width, and y_center and height by image height.
• Class numbers are zero-indexed (start from 0).

The label file corresponding to the above image contains 2 persons (class 0) and a tie (class 27):

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[LiberiFatali]

    Box coordinates are in normalized xywh format (from 0 - 1). If your boxes are in pixels, divide x_center and w by image width, and y_center and h by image height.
    The image height here refers to the **original size of the image or the resized size 416**？？thank you！

So I think it is the original size of the image.

[glenn-jocher]

@LiberiFatali yes, you are correct. The image height refers to the original size of the image, not the resized size of 416. If your boxes are in pixels, divide x_center and width (w) by the original image width, and y_center and height (h) by the original image height. Thank you!