How to indexing IValue in java? (my case : tuple of [1,496,640,2])

Hi, I have java.torch.Size([1, 496, 640, 2]) <- outputs

IValue[] outputs = model.forward(inputs).toTuple()

which is IValue

I want to get [1,:,:,1] and [1,:,:,2] by java command…
how can I get this? also…what is the correspondence of the np.array in java?
I want to get [1,:,:,1] and [1,:,:,2] as float.array in java.

why pytorch has very few examples??