Should I give the id of each object on the same category when labelling images for tracking?

[anthonyweidai]

Hi, I want to create my dataset to track some objects. I am confused how to correctly label images. For example, if I want to track each people, should I label them with different id (0, 1, 2, 3) in the same frame on my dataset? I saw the video on the official website of mot. I found that their groundtruth has id in each objects on the same category.