Source code for cellpose.resnet_torch

"""
Copyright © 2023 Howard Hughes Medical Institute, Authored by Carsen Stringer and Marius Pachitariu.
"""

import os, sys, time, shutil, tempfile, datetime, pathlib, subprocess
import numpy as np
import torch
import torch.nn as nn
from torch import optim
import torch.nn.functional as F
import datetime

from . import transforms, io, dynamics, utils


def batchconv(in_channels, out_channels, sz, conv_3D=False):
    conv_layer = nn.Conv3d if conv_3D else nn.Conv2d
    batch_norm = nn.BatchNorm3d if conv_3D else nn.BatchNorm2d
    return nn.Sequential(
        batch_norm(in_channels, eps=1e-5, momentum=0.05),
        nn.ReLU(inplace=True),
        conv_layer(in_channels, out_channels, sz, padding=sz // 2),
    )


def batchconv0(in_channels, out_channels, sz, conv_3D=False):
    conv_layer = nn.Conv3d if conv_3D else nn.Conv2d
    batch_norm = nn.BatchNorm3d if conv_3D else nn.BatchNorm2d
    return nn.Sequential(
        batch_norm(in_channels, eps=1e-5, momentum=0.05),
        conv_layer(in_channels, out_channels, sz, padding=sz // 2),
    )


[docs]class resdown(nn.Module): def __init__(self, in_channels, out_channels, sz, conv_3D=False): super().__init__() self.conv = nn.Sequential() self.proj = batchconv0(in_channels, out_channels, 1, conv_3D) for t in range(4): if t == 0: self.conv.add_module("conv_%d" % t, batchconv(in_channels, out_channels, sz, conv_3D)) else: self.conv.add_module("conv_%d" % t, batchconv(out_channels, out_channels, sz, conv_3D)) def forward(self, x): x = self.proj(x) + self.conv[1](self.conv[0](x)) x = x + self.conv[3](self.conv[2](x)) return x
[docs]class downsample(nn.Module): def __init__(self, nbase, sz, conv_3D=False, max_pool=True): super().__init__() self.down = nn.Sequential() if max_pool: self.maxpool = nn.MaxPool3d(2, stride=2) if conv_3D else nn.MaxPool2d( 2, stride=2) else: self.maxpool = nn.AvgPool3d(2, stride=2) if conv_3D else nn.AvgPool2d( 2, stride=2) for n in range(len(nbase) - 1): self.down.add_module("res_down_%d" % n, resdown(nbase[n], nbase[n + 1], sz, conv_3D)) def forward(self, x): xd = [] for n in range(len(self.down)): if n > 0: y = self.maxpool(xd[n - 1]) else: y = x xd.append(self.down[n](y)) return xd
[docs]class batchconvstyle(nn.Module): def __init__(self, in_channels, out_channels, style_channels, sz, conv_3D=False): super().__init__() self.concatenation = False self.conv = batchconv(in_channels, out_channels, sz, conv_3D) self.full = nn.Linear(style_channels, out_channels) def forward(self, style, x, mkldnn=False, y=None): if y is not None: x = x + y feat = self.full(style) for k in range(len(x.shape[2:])): feat = feat.unsqueeze(-1) if mkldnn: x = x.to_dense() y = (x + feat).to_mkldnn() else: y = x + feat y = self.conv(y) return y
[docs]class resup(nn.Module): def __init__(self, in_channels, out_channels, style_channels, sz, conv_3D=False): super().__init__() self.concatenation = False self.conv = nn.Sequential() self.conv.add_module("conv_0", batchconv(in_channels, out_channels, sz, conv_3D=conv_3D)) self.conv.add_module( "conv_1", batchconvstyle(out_channels, out_channels, style_channels, sz, conv_3D=conv_3D)) self.conv.add_module( "conv_2", batchconvstyle(out_channels, out_channels, style_channels, sz, conv_3D=conv_3D)) self.conv.add_module( "conv_3", batchconvstyle(out_channels, out_channels, style_channels, sz, conv_3D=conv_3D)) self.proj = batchconv0(in_channels, out_channels, 1, conv_3D=conv_3D) def forward(self, x, y, style, mkldnn=False): x = self.proj(x) + self.conv[1](style, self.conv[0](x), y=y, mkldnn=mkldnn) x = x + self.conv[3](style, self.conv[2](style, x, mkldnn=mkldnn), mkldnn=mkldnn) return x
[docs]class make_style(nn.Module): def __init__(self, conv_3D=False): super().__init__() self.flatten = nn.Flatten() self.avg_pool = F.avg_pool3d if conv_3D else F.avg_pool2d def forward(self, x0): style = self.avg_pool(x0, kernel_size=x0.shape[2:]) style = self.flatten(style) style = style / torch.sum(style**2, axis=1, keepdim=True)**.5 return style
[docs]class upsample(nn.Module): def __init__(self, nbase, sz, conv_3D=False): super().__init__() self.upsampling = nn.Upsample(scale_factor=2, mode="nearest") self.up = nn.Sequential() for n in range(1, len(nbase)): self.up.add_module("res_up_%d" % (n - 1), resup(nbase[n], nbase[n - 1], nbase[-1], sz, conv_3D)) def forward(self, style, xd, mkldnn=False): x = self.up[-1](xd[-1], xd[-1], style, mkldnn=mkldnn) for n in range(len(self.up) - 2, -1, -1): if mkldnn: x = self.upsampling(x.to_dense()).to_mkldnn() else: x = self.upsampling(x) x = self.up[n](x, xd[n], style, mkldnn=mkldnn) return x
[docs]class CPnet(nn.Module): """ CPnet is the Cellpose neural network model used for cell segmentation and image restoration. Args: nbase (list): List of integers representing the number of channels in each layer of the downsample path. nout (int): Number of output channels. sz (int): Size of the input image. mkldnn (bool, optional): Whether to use MKL-DNN acceleration. Defaults to False. conv_3D (bool, optional): Whether to use 3D convolution. Defaults to False. max_pool (bool, optional): Whether to use max pooling. Defaults to True. diam_mean (float, optional): Mean diameter of the cells. Defaults to 30.0. Attributes: nbase (list): List of integers representing the number of channels in each layer of the downsample path. nout (int): Number of output channels. sz (int): Size of the input image. residual_on (bool): Whether to use residual connections. style_on (bool): Whether to use style transfer. concatenation (bool): Whether to use concatenation. conv_3D (bool): Whether to use 3D convolution. mkldnn (bool): Whether to use MKL-DNN acceleration. downsample (nn.Module): Downsample blocks of the network. upsample (nn.Module): Upsample blocks of the network. make_style (nn.Module): Style module, avgpool's over all spatial positions. output (nn.Module): Output module - batchconv layer. diam_mean (nn.Parameter): Parameter representing the mean diameter to which the cells are rescaled to during training. diam_labels (nn.Parameter): Parameter representing the mean diameter of the cells in the training set (before rescaling). """ def __init__(self, nbase, nout, sz, mkldnn=False, conv_3D=False, max_pool=True, diam_mean=30.): super().__init__() self.nbase = nbase self.nout = nout self.sz = sz self.residual_on = True self.style_on = True self.concatenation = False self.conv_3D = conv_3D self.mkldnn = mkldnn if mkldnn is not None else False self.downsample = downsample(nbase, sz, conv_3D=conv_3D, max_pool=max_pool) nbaseup = nbase[1:] nbaseup.append(nbaseup[-1]) self.upsample = upsample(nbaseup, sz, conv_3D=conv_3D) self.make_style = make_style(conv_3D=conv_3D) self.output = batchconv(nbaseup[0], nout, 1, conv_3D=conv_3D) self.diam_mean = nn.Parameter(data=torch.ones(1) * diam_mean, requires_grad=False) self.diam_labels = nn.Parameter(data=torch.ones(1) * diam_mean, requires_grad=False) @property def device(self): """ Get the device of the model. Returns: torch.device: The device of the model. """ return next(self.parameters()).device
[docs] def forward(self, data): """ Forward pass of the CPnet model. Args: data (torch.Tensor): Input data. Returns: tuple: A tuple containing the output tensor, style tensor, and downsampled tensors. """ if self.mkldnn: data = data.to_mkldnn() T0 = self.downsample(data) if self.mkldnn: style = self.make_style(T0[-1].to_dense()) else: style = self.make_style(T0[-1]) style0 = style if not self.style_on: style = style * 0 T1 = self.upsample(style, T0, self.mkldnn) T1 = self.output(T1) if self.mkldnn: T0 = [t0.to_dense() for t0 in T0] T1 = T1.to_dense() return T1, style0, T0
[docs] def save_model(self, filename): """ Save the model to a file. Args: filename (str): The path to the file where the model will be saved. """ torch.save(self.state_dict(), filename)
[docs] def load_model(self, filename, device=None): """ Load the model from a file. Args: filename (str): The path to the file where the model is saved. device (torch.device, optional): The device to load the model on. Defaults to None. """ if (device is not None) and (device.type != "cpu"): state_dict = torch.load(filename, map_location=device) else: self.__init__(self.nbase, self.nout, self.sz, self.mkldnn, self.conv_3D, self.diam_mean) state_dict = torch.load(filename, map_location=torch.device("cpu")) if state_dict["output.2.weight"].shape[0] != self.nout: for name in self.state_dict(): if "output" not in name: self.state_dict()[name].copy_(state_dict[name]) else: self.load_state_dict( dict([(name, param) for name, param in state_dict.items()]), strict=False)