Make_grid can not deal with C=1?

Hi, I have a batch of imgs

In [11]: a=torch.ones(4,1,8,8)

In [12]: b=make_grid(a)

In [13]: b.shape
Out[13]: torch.Size([3, 12, 42])

I dont understand why make_grid will modify the output channel?

I think it’s modifying the output channels for easy visualization and saving. If you visualize the image with a library (e.g. matplotlib) you will see it’s still black and white.