60 lines
2.4 KiB
60 lines
2.4 KiB
2 months ago
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from pathlib import Path
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import torch
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from tinygrad import nn
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from tinygrad.tensor import Tensor
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from tinygrad.helpers import fetch, get_child
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class DownsampleBlock:
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def __init__(self, c0, c1, stride=2):
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self.conv1 = [nn.Conv2d(c0, c1, kernel_size=(3,3,3), stride=stride, padding=(1,1,1,1,1,1), bias=False), nn.InstanceNorm(c1), Tensor.relu]
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self.conv2 = [nn.Conv2d(c1, c1, kernel_size=(3,3,3), padding=(1,1,1,1,1,1), bias=False), nn.InstanceNorm(c1), Tensor.relu]
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def __call__(self, x):
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return x.sequential(self.conv1).sequential(self.conv2)
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class UpsampleBlock:
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def __init__(self, c0, c1):
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self.upsample_conv = [nn.ConvTranspose2d(c0, c1, kernel_size=(2,2,2), stride=2)]
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self.conv1 = [nn.Conv2d(2 * c1, c1, kernel_size=(3,3,3), padding=(1,1,1,1,1,1), bias=False), nn.InstanceNorm(c1), Tensor.relu]
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self.conv2 = [nn.Conv2d(c1, c1, kernel_size=(3,3,3), padding=(1,1,1,1,1,1), bias=False), nn.InstanceNorm(c1), Tensor.relu]
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def __call__(self, x, skip):
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x = x.sequential(self.upsample_conv)
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x = Tensor.cat(x, skip, dim=1)
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return x.sequential(self.conv1).sequential(self.conv2)
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class UNet3D:
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def __init__(self, in_channels=1, n_class=3):
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filters = [32, 64, 128, 256, 320]
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inp, out = filters[:-1], filters[1:]
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self.input_block = DownsampleBlock(in_channels, filters[0], stride=1)
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self.downsample = [DownsampleBlock(i, o) for i, o in zip(inp, out)]
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self.bottleneck = DownsampleBlock(filters[-1], filters[-1])
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self.upsample = [UpsampleBlock(filters[-1], filters[-1])] + [UpsampleBlock(i, o) for i, o in zip(out[::-1], inp[::-1])]
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self.output = {"conv": nn.Conv2d(filters[0], n_class, kernel_size=(1, 1, 1))}
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def __call__(self, x):
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x = self.input_block(x)
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outputs = [x]
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for downsample in self.downsample:
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x = downsample(x)
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outputs.append(x)
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x = self.bottleneck(x)
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for upsample, skip in zip(self.upsample, outputs[::-1]):
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x = upsample(x, skip)
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x = self.output["conv"](x)
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return x
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def load_from_pretrained(self):
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fn = Path(__file__).parents[1] / "weights" / "unet-3d.ckpt"
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fetch("https://zenodo.org/record/5597155/files/3dunet_kits19_pytorch.ptc?download=1", fn)
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state_dict = torch.jit.load(fn, map_location=torch.device("cpu")).state_dict()
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for k, v in state_dict.items():
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obj = get_child(self, k)
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assert obj.shape == v.shape, (k, obj.shape, v.shape)
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obj.assign(v.numpy())
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if __name__ == "__main__":
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mdl = UNet3D()
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mdl.load_from_pretrained()
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