pretrained 3d resnet

[JianJuly]

Describe the bug
i intend to use pretrained resnet50 for feature extraction.
so first i tried the following codes

from monai.networks import nets
model = nets.resnet50(pretrained=True)

It raises NotImplementedError: Currently not implemented, see comments in source code

then i manually download the pretrained weights from https://github.com/Tencent/MedicalNet, and load it.
Yet it raises size mismatch for conv1.weight: copying a param with shape torch.Size([64, 1, 7, 7, 7]) from checkpoint, the shape in current model is torch.Size([64, 3, 7, 7, 7]).

I found that the first conv of resnet50 we import here is of shape 3×7×7×7, while it of pretrained weights if 1×7×7×7.
How can i address it?

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[Nic-Ma]

Hi @JianJuly ,

Thanks for your interest and experiments here.
I think to use the pretrained weights, maybe you need to set your input channel of resnet50 to 1 channel:

resnet50(..., n_input_channels=1)

Add @yiheng-wang-nv for further discussion.

Thanks.

[JianJuly]

@Nic-Ma Thank you for your quick reply. Another question is when will model = nets.resnet50(pretrained=True) accessible? or is there any easier way to use pretrained resnet (on 23 medical datasets) ?

[Nic-Ma]

Hi @JianJuly ,

I think it's still under discussion, we plan to provide some model zoo features in the short future.
@yiheng-wang-nv is there any easier way to use pretrained resnet (on 23 medical datasets)?

Thanks.

[wyli]

this becomes a duplicate of Project-MONAI/model-zoo#48, I'm closing this for now.

[Borda]

I have tried to work with the referred weights but getting a compatibility issue: Project-MONAI/model-zoo#48