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Generate one hot labels from integer labels in PyTorch
def make_one_hot(labels, C=2):
Converts an integer label torch.autograd.Variable to a one-hot Variable.
labels : torch.autograd.Variable of torch.cuda.LongTensor
N x 1 x H x W, where N is batch size.
Each value is an integer representing correct classification.
C : integer.
number of classes in labels.
target : torch.autograd.Variable of torch.cuda.FloatTensor
N x C x H x W, where C is class number. One-hot encoded.
one_hot = torch.cuda.FloatTensor(labels.size(0), C, labels.size(2), labels.size(3)).zero_()
target = one_hot.scatter_(1,, 1)
target = Variable(target)
return target
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depthwise commented Nov 10, 2019

Note that PyTorch's one_hot expands the last dimension, so the resulting tensor is NHWC rather than PyTorch standard NCHW which your prediction is likely to come in. To turn it into NCHW, one would need to add .permute(0,3,1,2)

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