RuntimeError: non-empty 3D or 4D (batch mode) tensor expected for input

[GitSwar90]

from convcrf import convcrf

config = convcrf.default_conf
shape = [3,416,416]
nclasses = 15

crf = convcrf.GaussCRF(config, shape, nclasses)
crf.cuda()

img = torch.randn(1,3,416,416).cuda()
un = torch.randn(1,15,416,416).cuda()
un = torch.softmax(un,dim=1)

pred = crf.forward(un, img)

ERROR:
Traceback (most recent call last):

File "", line 1, in
pred = crf.forward(un, img)

File "...\anaconda3\lib\site-packages\convcrf-1.0-py3.7.egg\convcrf\convcrf.py", line 202, in forward
compats, conf['merge'])

File "...\anaconda3\lib\site-packages\convcrf-1.0-py3.7.egg\convcrf\convcrf.py", line 574, in add_pairwise_energies
pyinn=self.pyinn)

File "...\anaconda3\lib\site-packages\convcrf-1.0-py3.7.egg\convcrf\convcrf.py", line 311, in init
gaussian = self._create_convolutional_filters(feats)

File "...\anaconda3\lib\site-packages\convcrf-1.0-py3.7.egg\convcrf\convcrf.py", line 353, in _create_convolutional_filters
count_include_pad=False)

RuntimeError: non-empty 3D or 4D (batch mode) tensor expected for input