About object features

[Chevalier1024]

Hi~, thank you for your great work. I have one question about the object features. The object features files just contain object features and objects' bounding boxes, how can I know the object class and attributes? I know that sceneGraphs.zip provides information about the objects, attributes and relations in the image, but how does this information correspond to the object features files?
Looking forward for your response, thank you~