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m_4 = nn.CrossEntropyLoss(size_average=True, weight=alpha4)
loss = 0.0
'''
GWTA Loss
'''
for idx, (m, out, yss) in enumerate(zip([m_1, m_2, m_3, m_4], outputs, Yss_argmax)):
if idx != 0:
loss_ = self.gwta_loss(out, yss, m, grid_factor=np.power(2, idx))
else:
loss_ = m(out, yss)
loss += loss_
losses.append(loss_.item())
loss.backward()
self.optimizers.step()
# -- Histogram of boxes for weighting --
for out_idx, (out, yss) in enumerate(zip(outputs[::-1], Yss_out[::-1])):
out_argmax = torch.argmax(out, dim=1)
bin_ = np.bincount(out_argmax.cpu().data.numpy().flatten())
ii = np.nonzero(bin_)[0]
hist_boxes[ii+4*out_idx] += bin_[ii]
Yss_argmax = torch.argmax(yss, dim=1)
bin_gt = np.bincount(Yss_argmax.cpu().data.numpy().flatten())
ii_gt = np.nonzero(bin_gt)[0]
hist_boxes_gt[ii_gt+4*out_idx] += bin_gt[ii_gt]
return losses, hist_boxes, hist_boxes_gt
'''
Test function for LSC-CNN.
Parameters
-----------
X - (np.ndarray) Image patches (Bx3XHxW)
Y - (np.ndarray) Ground truth in highest scale (BX1XHXW)
Returns
---------
losses: (list of float) list of loss values of each scale.
upsample_pred: (list) list of torch tensor predictions for each scale ([Bx4xHxW] * number of scales)
upscaled to the prediction scale
upsample_gt: (list) list of torch tensor gt for each scale ([Bx4xHxW] * number of scales)
upscaled to the prediction scale
NOTE: Here 4 denotes the number of channels in prediction. In LSC-CNN 4 represents
[b_1, b_2, b_3, z] where b_i are boxes and z is the background.
'''
def test_function(X, Y, loss_weights, network):
Y = (Y>0).astype(np.float32)
if torch.cuda.is_available():
X = torch.autograd.Variable(torch.from_numpy(X)).cuda()
X_clone = X.clone()
Y = torch.autograd.Variable(torch.from_numpy(Y)).cuda()
Yss = [Y]
else:
assert(0)
network = network.cuda()
output = network(X, None)
for s in range(0, 3):
Yss.append(torch.nn.functional.avg_pool2d(Yss[s], (2, 2)) * 4)
assert(torch.sum(Yss[0]) == torch.sum(Yss[1]))
# Making 4 channel ground truth
Yss_out = self.get_box_gt(Yss)
Yss = Yss[::-1]
Yss_out = Yss_out[::-1]
Yss_argmax = [torch.argmax(yss, dim=1) for yss in Yss_out]
alpha1 = torch.cuda.FloatTensor(loss_weights[3]) # 1/16 scale
alpha2 = torch.cuda.FloatTensor(loss_weights[2]) # 1/8 scale
alpha3 = torch.cuda.FloatTensor(loss_weights[1]) # 1/4 scale
alpha4 = torch.cuda.FloatTensor(loss_weights[0]) # 1/2 scale
m_1 = nn.CrossEntropyLoss(size_average=True, weight=alpha1)
m_2 = nn.CrossEntropyLoss(size_average=True, weight=alpha2)
m_3 = nn.CrossEntropyLoss(size_average=True, weight=alpha3)
m_4 = nn.CrossEntropyLoss(size_average=True, weight=alpha4)
loss = 0.0
for (out, yss, m) in zip(output, Yss_argmax, [m_1, m_2, m_3, m_4]):
loss += m(out, yss)
out_softmax = [nn.functional.softmax(o, dim=1) for o in output]
out_argmax = [torch.argmax(o, dim=1) for o in out_softmax]
upsample_max = int(np.log2(16 // output_downscale))
upsample_gt = []
upsample_pred = []
for idx, (yss_out, out) in enumerate(zip(Yss_out, output)):
out = nn.functional.softmax(out, dim=1)
upsample_yss_out = yss_out
upsample_out = out
for n in range(upsample_max-idx):