diff --git a/.gitignore b/.gitignore index fedd499d..351e54b8 100644 --- a/.gitignore +++ b/.gitignore @@ -129,3 +129,5 @@ temp/ # VSCode .vscode/ *.zip +models/*/models/* +models/*/output/* diff --git a/ci/bundle_custom_data.py b/ci/bundle_custom_data.py index 0ac2bdef..6f20d112 100644 --- a/ci/bundle_custom_data.py +++ b/ci/bundle_custom_data.py @@ -22,6 +22,7 @@ "brats_mri_axial_slices_generative_diffusion", "maisi_ct_generative", "cxr_image_synthesis_latent_diffusion_model", + "brain_image_synthesis_latent_diffusion_model", ] # This list is used for our CI tests to determine whether a bundle contains the preferred files. @@ -45,6 +46,7 @@ "vista2d", "mednist_ddpm", "cxr_image_synthesis_latent_diffusion_model", + "brain_image_synthesis_latent_diffusion_model", ] # This list is used for our CI tests to determine whether a bundle needs to be tested after downloading diff --git a/ci/unit_tests/test_brain_image_synthesis_latent_diffusion_model.py b/ci/unit_tests/test_brain_image_synthesis_latent_diffusion_model.py new file mode 100644 index 00000000..93fa0c40 --- /dev/null +++ b/ci/unit_tests/test_brain_image_synthesis_latent_diffusion_model.py @@ -0,0 +1,47 @@ +# Copyright (c) MONAI Consortium +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# http://www.apache.org/licenses/LICENSE-2.0 +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +import os +import unittest + +from monai.bundle import ConfigWorkflow +from parameterized import parameterized +from utils import check_workflow + +TEST_CASE_1 = [ # inference + { + "bundle_root": "models/brain_image_synthesis_latent_diffusion_model", + "gender": 1.0, + "age": 0.7, + "ventricular_vol": 0.7, + "brain_vol": 0.5, + } +] + + +class BrainImageSynthesisLatentDiffusionModel(unittest.TestCase): + @parameterized.expand([TEST_CASE_1]) + def test_inference(self, params): + bundle_root = params["bundle_root"] + inference_file = os.path.join(bundle_root, "configs/inference.json") + trainer = ConfigWorkflow( + workflow_type="inference", + config_file=inference_file, + logging_file=os.path.join(bundle_root, "configs/logging.conf"), + meta_file=os.path.join(bundle_root, "configs/metadata.json"), + **params, + ) + check_workflow(trainer, check_properties=True) + + +if __name__ == "__main__": + loader = unittest.TestLoader() + unittest.main(testLoader=loader) diff --git a/ci/verify_bundle.py b/ci/verify_bundle.py index 7beca3e5..283c09b1 100644 --- a/ci/verify_bundle.py +++ b/ci/verify_bundle.py @@ -54,6 +54,8 @@ def _get_weights_names(bundle: str): if bundle == "pediatric_abdominal_ct_segmentation": # skip test for this bundle's ts file return "dynunet_FT.pt", None + if bundle == "brain_image_synthesis_latent_diffusion": + return "autoencoder.pt", "model.pt" if bundle == "cxr_image_synthesis_latent_diffusion_model": return "autoencoder.pt", None return "model.pt", "model.ts" diff --git a/models/brain_image_synthesis_latent_diffusion_model/LICENSE b/models/brain_image_synthesis_latent_diffusion_model/LICENSE new file mode 100644 index 00000000..261eeb9e --- /dev/null +++ b/models/brain_image_synthesis_latent_diffusion_model/LICENSE @@ -0,0 +1,201 @@ + Apache License + Version 2.0, January 2004 + http://www.apache.org/licenses/ + + TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION + + 1. 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We also recommend that a + file or class name and description of purpose be included on the + same "printed page" as the copyright notice for easier + identification within third-party archives. + + Copyright [yyyy] [name of copyright owner] + + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. diff --git a/models/brain_image_synthesis_latent_diffusion_model/configs/inference.json b/models/brain_image_synthesis_latent_diffusion_model/configs/inference.json new file mode 100644 index 00000000..206d1130 --- /dev/null +++ b/models/brain_image_synthesis_latent_diffusion_model/configs/inference.json @@ -0,0 +1,112 @@ +{ + "imports": [ + "$import torch", + "$from datetime import datetime", + "$from pathlib import Path" + ], + "bundle_root": ".", + "dataset_dir": "", + "dataset": "", + "evaluator": "", + "inferer": "", + "load_old": 1, + "model_dir": "$@bundle_root + '/models'", + "output_dir": "$@bundle_root + '/output'", + "create_output_dir": "$Path(@output_dir).mkdir(exist_ok=True)", + "gender": 0.0, + "age": 0.1, + "ventricular_vol": 0.2, + "brain_vol": 0.4, + "device": "$torch.device('cuda:0' if torch.cuda.is_available() else 'cpu')", + "conditioning": "$torch.tensor([[@gender, @age, @ventricular_vol, @brain_vol]]).to(@device).unsqueeze(1)", + "out_file": "$datetime.now().strftime('sample_%H%M%S_%d%m%Y') + '_' + str(@gender) + '_' + str(@age) + '_' + str(@ventricular_vol) + '_' + str(@brain_vol)", + "autoencoder_def": { + "_target_": "monai.networks.nets.AutoencoderKL", + "spatial_dims": 3, + "in_channels": 1, + "out_channels": 1, + "latent_channels": 3, + "channels": [ + 64, + 128, + 128, + 128 + ], + "num_res_blocks": 2, + "norm_num_groups": 32, + "norm_eps": 1e-06, + "attention_levels": [ + false, + false, + false, + false + ], + "with_encoder_nonlocal_attn": false, + "with_decoder_nonlocal_attn": false + }, + "network_def": "@autoencoder_def", + "load_autoencoder_path": "$@model_dir + '/autoencoder.pt'", + "load_autoencoder_func": "$@autoencoder_def.load_old_state_dict if bool(@load_old) else @autoencoder_def.load_state_dict", + "load_autoencoder": "$@load_autoencoder_func(torch.load(@load_autoencoder_path))", + "autoencoder": "$@autoencoder_def.to(@device)", + "diffusion_def": { + "_target_": "monai.networks.nets.DiffusionModelUNet", + "spatial_dims": 3, + "in_channels": 7, + "out_channels": 3, + "channels": [ + 256, + 512, + 768 + ], + "num_res_blocks": 2, + "attention_levels": [ + false, + true, + true + ], + "norm_num_groups": 32, + "norm_eps": 1e-06, + "resblock_updown": true, + "num_head_channels": [ + 0, + 512, + 768 + ], + "with_conditioning": true, + "transformer_num_layers": 1, + "cross_attention_dim": 4, + "upcast_attention": true, + "use_flash_attention": false + }, + "load_diffusion_path": "$@model_dir + '/model.pt'", + "load_diffusion_func": "$@diffusion_def.load_old_state_dict if bool(@load_old) else @diffusion_def.load_state_dict", + "load_diffusion": "$@load_diffusion_func(torch.load(@load_diffusion_path))", + "diffusion": "$@diffusion_def.to(@device)", + "scheduler": { + "_target_": "monai.networks.schedulers.DDIMScheduler", + "_requires_": [ + "@load_diffusion", + "@load_autoencoder" + ], + "beta_start": 0.0015, + "beta_end": 0.0205, + "num_train_timesteps": 1000, + "schedule": "scaled_linear_beta", + "clip_sample": false + }, + "noise": "$torch.randn((1, 3, 20, 28, 20)).to(@device)", + "set_timesteps": "$@scheduler.set_timesteps(num_inference_steps=50)", + "sampler": { + "_target_": "scripts.sampler.Sampler", + "_requires_": "@set_timesteps" + }, + "sample": "$@sampler.sampling_fn(@noise, @autoencoder, @diffusion, @scheduler, @conditioning)", + "saver": { + "_target_": "SaveImage", + "_requires_": "@create_output_dir", + "output_dir": "@output_dir", + "output_postfix": "@out_file" + }, + "run": "$@saver(@sample[0][0])" +} diff --git a/models/brain_image_synthesis_latent_diffusion_model/configs/logging.conf b/models/brain_image_synthesis_latent_diffusion_model/configs/logging.conf new file mode 100644 index 00000000..91c1a21c --- /dev/null +++ b/models/brain_image_synthesis_latent_diffusion_model/configs/logging.conf @@ -0,0 +1,21 @@ +[loggers] +keys=root + +[handlers] +keys=consoleHandler + +[formatters] +keys=fullFormatter + +[logger_root] +level=INFO +handlers=consoleHandler + +[handler_consoleHandler] +class=StreamHandler +level=INFO +formatter=fullFormatter +args=(sys.stdout,) + +[formatter_fullFormatter] +format=%(asctime)s - %(name)s - %(levelname)s - %(message)s diff --git a/models/brain_image_synthesis_latent_diffusion_model/configs/metadata.json b/models/brain_image_synthesis_latent_diffusion_model/configs/metadata.json new file mode 100644 index 00000000..40da5460 --- /dev/null +++ b/models/brain_image_synthesis_latent_diffusion_model/configs/metadata.json @@ -0,0 +1,77 @@ +{ + "schema": "https://github.com/Project-MONAI/MONAI-extra-test-data/releases/download/0.8.1/meta_schema_20240725.json", + "version": "1.0.0", + "changelog": { + "1.0.0": "Initial release" + }, + "monai_version": "1.4.0", + "pytorch_version": "2.5.1", + "numpy_version": "1.26.4", + "required_packages_version": { + "nibabel": "5.3.2" + }, + "task": "Brain image synthesis", + "description": "A generative model for creating high-resolution 3D brain MRI based on UK Biobank", + "authors": "Walter H. L. Pinaya, Petru-Daniel Tudosiu, Jessica Dafflon, Pedro F Da Costa, Virginia Fernandez, Parashkev Nachev, Sebastien Ourselin, and M. Jorge Cardoso", + "copyright": "Copyright (c) MONAI Consortium", + "data_source": "https://www.ukbiobank.ac.uk/", + "data_type": "nibabel", + "image_classes": "T1w head MRI with 1x1x1 mm voxel size", + "eval_metrics": { + "fid": 0.0076, + "msssim": 0.6555, + "4gmsssim": 0.3883 + }, + "intended_use": "This is a research tool/prototype and not to be used clinically", + "references": [ + "Pinaya, Walter HL, et al. \"Brain imaging generation with latent diffusion models.\" MICCAI Workshop on Deep Generative Models. Springer, Cham, 2022." + ], + "network_data_format": { + "inputs": { + "image": { + "type": "tabular", + "num_channels": 1, + "dtype": "float32", + "value_range": [ + 0, + 1 + ], + "format": "nii", + "spatial_shape": [ + 160, + 224, + 160 + ], + "is_patch_data": false, + "channel_def": { + "0": "Gender", + "1": "Age", + "2": "Ventricular volume", + "3": "Brain volume" + } + } + }, + "outputs": { + "pred": { + "type": "image", + "format": "image", + "num_channels": 1, + "spatial_shape": [ + 160, + 224, + 160 + ], + "dtype": "float32", + "value_range": [ + 0, + 1 + ], + "modality": "MR", + "is_patch_data": false, + "channel_def": { + "0": "T1w" + } + } + } + } +} diff --git a/models/brain_image_synthesis_latent_diffusion_model/docs/README.md b/models/brain_image_synthesis_latent_diffusion_model/docs/README.md new file mode 100644 index 00000000..3d80474b --- /dev/null +++ b/models/brain_image_synthesis_latent_diffusion_model/docs/README.md @@ -0,0 +1,75 @@ +# Brain Imaging Generation with Latent Diffusion Models + +### **Authors** + +Walter H. L. Pinaya, Petru-Daniel Tudosiu, Jessica Dafflon, Pedro F Da Costa, Virginia Fernandez, Parashkev Nachev, +Sebastien Ourselin, and M. Jorge Cardoso + +### **Tags** +Synthetic data, Latent Diffusion Model, Generative model, Brain Imaging + +## **Model Description** +This model is trained using the Latent Diffusion Model architecture [1] and is used for the synthesis of conditioned 3D +brain MRI data. The model is divided into two parts: an autoencoder with a KL-regularisation model that compresses data +into a latent space and a diffusion model that learns to generate conditioned synthetic latent representations. This +model is conditioned on age, sex, the volume of ventricular cerebrospinal fluid, and brain volume normalised for head size. + +![](./figure_1.png)
+

+Figure 1 - Synthetic image from the model.

+ + +## **Data** +The model was trained on brain data from 31,740 participants from the UK Biobank [2]. We used high-resolution 3D T1w MRI with voxel size of 1mm3, resulting in volumes with 160 x 224 x 160 voxels + +#### **Preprocessing** +We used UniRes [3] to perform a rigid body registration to a common MNI space for image pre-processing. The voxel intensity was normalised to be between [0, 1]. + +## **Performance** +This model achieves the following results on UK Biobank: an FID of 0.0076, an MS-SSIM of 0.6555, and a 4-G-R-SSIM of 0.3883. + +Please, check Table 1 of the original paper for more details regarding evaluation results. + + +## **commands example** + +Execute sampling: + +```shell +python -m monai.bundle run --config_file configs/inference.json --gender 1.0 --age 0.7 --ventricular_vol 0.7 --brain_vol 0.5 +``` + +All conditioning are expected to have values between 0 and 1 + +## Using a new version of the model + +If you want to use the checkpoints from a newly fine-tuned model, you need to set parameter load_old to 0 when you run inference, +to avoid the function load_old_state_dict being called instead of load_state_dict to be called, currently default, as it is +required to load the checkpoint from the original GenerativeModels repository. + +```shell +python -m monai.bundle run --config_file configs/inference.json --gender 1.0 --age 0.7 --ventricular_vol 0.7 --brain_vol 0.5 --load_old 0 +``` + +## **Citation Info** + +```bibtex +@inproceedings{pinaya2022brain, + title={Brain imaging generation with latent diffusion models}, + author={Pinaya, Walter HL and Tudosiu, Petru-Daniel and Dafflon, Jessica and Da Costa, Pedro F and Fernandez, Virginia and Nachev, Parashkev and Ourselin, Sebastien and Cardoso, M Jorge}, + booktitle={MICCAI Workshop on Deep Generative Models}, + pages={117--126}, + year={2022}, + organization={Springer} +} +``` + +## **References** + +Example: + +[1] Pinaya, Walter HL, et al. "Brain imaging generation with latent diffusion models." MICCAI Workshop on Deep Generative Models. Springer, Cham, 2022. + +[2] Sudlow, Cathie, et al. "UK biobank: an open access resource for identifying the causes of a wide range of complex diseases of middle and old age." PLoS medicine 12.3 (2015): e1001779. + +[3] Brudfors, Mikael, et al. "MRI super-resolution using multi-channel total variation." Annual Conference on Medical Image Understanding and Analysis. Springer, Cham, 2018. diff --git a/models/brain_image_synthesis_latent_diffusion_model/docs/figure_1.png b/models/brain_image_synthesis_latent_diffusion_model/docs/figure_1.png new file mode 100644 index 00000000..b3bed96a Binary files /dev/null and b/models/brain_image_synthesis_latent_diffusion_model/docs/figure_1.png differ diff --git a/models/brain_image_synthesis_latent_diffusion_model/large_files.yml b/models/brain_image_synthesis_latent_diffusion_model/large_files.yml new file mode 100644 index 00000000..5dbed08f --- /dev/null +++ b/models/brain_image_synthesis_latent_diffusion_model/large_files.yml @@ -0,0 +1,9 @@ +large_files: + - path: "models/autoencoder.pt" + url: "https://drive.google.com/uc?export=download&id=1CZHwxHJWybOsDavipD0EorDPOo_mzNeX" + hash_val: "329e97b3085643ff235f11f049856242" + hash_type: "md5" + - path: "models/model.pt" + url: "https://drive.google.com/uc?export=download&id=1XO-ak93ZuOcGTCpgRtqgIeZq3dG5ExN6" + hash_val: "21c3047556fb671caf0556f1cce6ef22" + hash_type: "md5" diff --git a/models/brain_image_synthesis_latent_diffusion_model/scripts/__init__.py b/models/brain_image_synthesis_latent_diffusion_model/scripts/__init__.py new file mode 100644 index 00000000..e69de29b diff --git a/models/brain_image_synthesis_latent_diffusion_model/scripts/sampler.py b/models/brain_image_synthesis_latent_diffusion_model/scripts/sampler.py new file mode 100644 index 00000000..3058c470 --- /dev/null +++ b/models/brain_image_synthesis_latent_diffusion_model/scripts/sampler.py @@ -0,0 +1,45 @@ +from __future__ import annotations + +import torch +import torch.nn as nn +from monai.utils import optional_import +from torch.cuda.amp import autocast + +tqdm, has_tqdm = optional_import("tqdm", name="tqdm") + + +class Sampler: + def __init__(self) -> None: + super().__init__() + + @torch.no_grad() + def sampling_fn( + self, + input_noise: torch.Tensor, + autoencoder_model: nn.Module, + diffusion_model: nn.Module, + scheduler: nn.Module, + conditioning: torch.Tensor, + ) -> torch.Tensor: + if has_tqdm: + progress_bar = tqdm(scheduler.timesteps) + else: + progress_bar = iter(scheduler.timesteps) + + image = input_noise + cond_concat = conditioning.squeeze(1).unsqueeze(-1).unsqueeze(-1).unsqueeze(-1) + cond_concat = cond_concat.expand(list(cond_concat.shape[0:2]) + list(input_noise.shape[2:])) + for t in progress_bar: + with torch.no_grad(): + model_output = diffusion_model( + torch.cat((image, cond_concat), dim=1), + timesteps=torch.Tensor((t,)).to(input_noise.device).long(), + context=conditioning, + ) + image, _ = scheduler.step(model_output, t, image) + + with torch.no_grad(): + with autocast(): + sample = autoencoder_model.decode_stage_2_outputs(image) + + return sample