what is the target means in def forward(self, img, target=None)

[john81923]

def forward(self, img, target=None):

what does the target stand for in this function argument?
Is there a sample or description?
thanks

[taohan10200]

The target is a dict packaged from the annotation, you can find its specific meaning in this script dataset.py

def HT21_ImgPath_and_Target(base_path,i):
    img_path = []
    labels=[]
    root  = osp.join(base_path, i + '/img1')
    img_ids = os.listdir(root)
    img_ids.sort()
    gts = defaultdict(list)
    with open(osp.join(root.replace('img1', 'gt'), 'gt.txt'), 'r') as f:
        lines = f.readlines()
        for lin in lines:
            lin_list = [float(i) for i in lin.rstrip().split(',')]
            ind = int(lin_list[0])
            gts[ind].append(lin_list)
    for img_id in img_ids:
        img_id = img_id.strip()
        single_path = osp.join(root, img_id)
        annotation  = gts[int(img_id.split('.')[0])]
        annotation = torch.tensor(annotation,dtype=torch.float32)
        box = annotation[:,2:6]
        points =   box[:,0:2] + box[:,2:4]/2
        sigma = torch.min(box[:,2:4], 1)[0] / 2.
        ids = annotation[:,1].long()
        img_path.append(single_path)
        labels.append({'scene_name':i,'frame':int(img_id.split('.')[0]), 'person_id':ids, 'points':points,'sigma':sigma})
    return img_path, labels