执行eval_voc,Expected 4-dimensional input for 4-dimensional weight 64 3 7 7, but got 3-dimensional input of size [3, 448, 448] instead

[Major Roszel]

Expected 4-dimensional input for 4-dimensional weight 64 3 7 7, but got 3-dimensional input of size [3, 448, 448] instead
增加了下面一行代码 ，出现了更多的问题。感谢感谢!!!
def predict_gpu(model,image_name,root_path=''):

result = []
image = cv2.imread(root_path+image_name)
h,w,_ = image.shape
img = cv2.resize(image,(448,448))
img = cv2.cvtColor(img,cv2.COLOR_BGR2RGB)
mean = (123,117,104)#RGB
img = img - np.array(mean,dtype=np.float32)

transform = transforms.Compose([transforms.ToTensor(),])
img = transform(img)
img = img.cuda()

**img = torch.unsqueeze(img, dim=0)**


pred = model(img) #1x7x7x30
pred = pred.cpu()
boxes,cls_indexs,probs =  decoder(pred)

for i,box in enumerate(boxes):
    x1 = int(box[0]*w)
    x2 = int(box[2]*w)
    y1 = int(box[1]*h)
    y2 = int(box[3]*h)
    cls_index = cls_indexs[i]
    cls_index = int(cls_index) # convert LongTensor to int
    prob = probs[i]
    prob = float(prob)
    result.append([(x1,y1),(x2,y2),VOC_CLASSES[cls_index],image_name,prob])
return result