- concatenate(boxlists: List[NpBoxList], fields: Optional[List[str]] = None) NpBoxList #
Concatenate list of BoxLists.
This op concatenates a list of input BoxLists into a larger BoxList. It also handles concatenation of BoxList fields as long as the field tensor shapes are equal except for the first dimension.
- A BoxList with number of boxes equal to
sum([boxlist.num_boxes() for boxlist in BoxList])
- Return type
ValueError – If boxlists is invalid (i.e., is not a list, is empty, or contains non BoxList objects), or if requested fields are not contained in all boxlists