Prepare Yolo v3 Custom Dataset

Hi all,

I am planning to explore Yolo model and use my custom dataset. I have all the images but quite confuse to prepare the dataset. I notice I must feed my model with data with specific format like below:

object-id center_x center_y width height

I do not understand with this setting. I understand that object-id is the class id and both width and height is images width and height but how can I calculate center_x and center_y? I understand there is a tool called LabelIMG but I want to do it manually.

Please advise

The Yolo format required params normalised wrt. the dimensions of the image.

So an object of class 3 with its center 20% of the way down from the top of the image and 30% of the way across from the left with a width equal to 10% of the image width and a height equal to 15% of the image height would be labelled as:

3 0.3 0.2 0.1 0.15

See here for more description: