def add_mask(tracklets):
    '''
        input the pieces of tracklets, add the mask overit, the padded 
        positions are set to be True, False for where box exists
    '''
    p, l = tracklets.shape[:2]
    sum_cord = torch.sum(tracklets[:,:,1:4], dim=2)
    mask = (sum_cord==0)
    return NestedTensor(tracklets, mask)

        input the pieces of tracklets, add the mask overit, the padded 
        positions are set to be True, False for where box exists
    
utils/misc.py