Question about torchvision.utils.make_grid ()

Hello,

In the tutorials of “VISUALIZING MODELS, DATA, AND TRAINING WITH TENSORBOARD”,Use iterator to view data,as follow:

testiter = iter(testloader)
images, labels = testiter.next()
images.shape
Out:
torch.Size([4, 1, 28, 28])

Why after the function torchvision.utils.make_grid (), the output becomes like this.:

torchvision.utils.make_grid(images).shape
Out:
torch.Size([3, 32, 122])

I don’t understand why the channel changed from 1 to 3.

Thank you.