Cited by 2,529Numerical methods in inverse problemsMedical Imaging Techniques and ApplicationsImage and Signal Denoising Methods

Deep Convolutional Neural Network for Inverse Problems in Imaging

Open access
Jin, Kyong Hwan, McCann, Michael T., Froustey, Emmanuel, Unser, Michael·2017·IEEE Transactions on Image Processing

Abstract

In this paper, we propose a novel deep convolutional neural network (CNN)-based algorithm for solving ill-posed inverse problems. Regularized iterative algorithms have emerged as the standard approach to ill-posed inverse problems in the past few decades. These methods produce excellent results, but can be challenging to deploy in practice due to factors including the high computational cost of the forward and adjoint operators and the difficulty of hyperparameter selection. The starting point of this paper is the observation that unrolled iterative methods have the form of a CNN (filtering followed by pointwise nonlinearity) when the normal operator (H*H, where H* is the adjoint of the forward imaging operator, H) of the forward model is a convolution. Based on this observation, we propose using direct inversion followed by a CNN to solve normal-convolutional inverse problems. The direct inversion encapsulates the physical model of the system, but leads to artifacts when the problem is ill posed; the CNN combines multiresolution decomposition and residual learning in order to learn to remove these artifacts while preserving image structure. We demonstrate the performance of the proposed network in sparse-view reconstruction (down to 50 views) on parallel beam X-ray computed tomography in synthetic phantoms as well as in real experimental sinograms. The proposed network outperforms total variation-regularized iterative reconstruction for the more realistic phantoms and requires less than a second to reconstruct a 512 × 512 image on the GPU.

AI snapshot

Written from the paper’s full text.

TL;DR

The paper proposes FBPConvNet, a deep CNN that takes a filtered back projection (FBP) reconstruction as input and learns to remove artifacts for inverse problems whose normal operator is a convolution, demonstrated on sparse-view X-ray CT. It reports competitive or better SNR than TV-regularized iterative reconstruction on realistic synthetic and real CT datasets, with sub-second GPU reconstruction.

Key findings

  • FBPConvNet outperformed TV-regularized iterative reconstruction on the biomedical synthetic dataset: at 143 views, SNR was 36.15 dB vs. 31.92 dB for TV; at 50 views, 28.83 dB vs. 25.20 dB.
  • On the real experimental CT dataset, FBPConvNet also had higher SNR than TV: 11.34 dB vs. 8.25 dB at 145 views, and 8.85 dB vs. 7.25 dB at 14× subsampling (table lists 51 views).
  • On the ellipsoidal synthetic dataset, TV outperformed FBPConvNet: 29.48 dB vs. 28.96 dB at 143 views, and 27.69 dB vs. 23.84 dB at 50 views; the paper attributes this to TV being optimal for piecewise-constant phantoms.
  • Reconstruction speed was about 200 ms for FBP plus 200–300 ms for the CNN on GPU for a 512 × 512 image, versus around 7 minutes for iterative reconstruction; the abstract states less than one second total.

Methods

  • Design: FBPConvNet applies discretized FBP to measurements, then a CNN based on U-net with multilevel decomposition, multichannel filtering, and residual learning via a skip connection; zero-padding is used and the final layer reduces 64 channels to a single output image. Training pairs low-view FBP images with full-view FBP images as input and output.
  • Data: three datasets—ellipsoid synthetic (500 images, sinograms 729 × 1,000), biomedical synthetic (500 real in-vivo CT images from the Mayo Clinic Low-dose Grand Challenge, sinograms 729 × 1,000), and experimental real CT (377 sinograms from the TOMCAT beamline, each 1,493 × 721, from rat brain z-slices). Synthetic data used 475 training and 25 test images; real data used 327 training and 25 test images with a 25-slice gap. Subsampling was ×7 and ×20 for synthetic (143 and 50 views) and ×5 and ×14 for real (145 and 52 views).
  • Analysis: SNR was the quantitative metric; FBP, TV-regularized iterative reconstruction [13], and FBPConvNet were compared. Training used MatConvNet, a Titan Black GPU, about 15 hours for 101 iterations, learning rate decreasing from 0.01 to 0.001, batch size 1, momentum 0.99, gradient clipping at 10⁻², and flip-flop augmentation. TV parameters were selected by golden-section search to optimize performance on the training set.

Limitations

  • Stated: the method lacks transfer between datasets; a network trained on ×7 subsampled sinograms retained artifacts when applied to ×20 subsampled sinograms, and different dimensions or subsampling factors require retraining.
  • Stated: the work focuses on X-ray CT; adapting to MRI or diffraction tomography is expected to be non-trivial experimentally, requiring large training sets and a high-quality iterative reconstruction for comparison, and complex-valued data would need a CNN architecture that correctly handles complex values.
  • Evident/acknowledged: TV outperformed FBPConvNet on the ellipsoidal piecewise-constant phantom, which the paper says is reasonable because TV regularization should be optimal there; the paper also notes TV parameters were tuned on the training set rather than learned from data, and the correct way to learn such parameters remains open.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1109/tip.2017.2713099

Cites

74 of 74 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 13 cited sources checked · 0 supported · 0 flagged

  • Findingnone given
    § Abstract · p. 1

    The proposed network requires less than a second to reconstruct a 512 × 512 image on the GPU.

    “requires less than a second to reconstruct a 512 × 512 image on the GPU.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: High-view FBP reconstructions can serve as ground truth for training and evaluation.
  • Findingown data
    § B. Biomedical Dataset · p. 13

    For the biomedical dataset, the sparse-view FBP contains line artifacts.

    “In Figure 5, again, the sparse-view FBP contains line artifacts.”
    Quote in the paperNot a substantial claim
  • Findingown data
    § A. Ellipsoidal Dataset · p. 11

    For the ellipsoidal dataset at 143 views, both the TV and FBPConvNet methods significantly reduce these artifacts, giving visually indistinguishable results.

    “Both the TV and FBPConvNet methods significantly reduce these artifacts, giving visually indistinguishable results.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: The training and test sets for the synthetic datasets are disjoint.
  • Findingnone given
    § Skip connection · p. 9

    Adding a skip connection between input and output (residual learning) yields a noticeable increase in performance compared to the same network without the skip connection.

    “This yields a noticeable increase in performance compared to the same network without the skip connection.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: High-view FBP reconstructions can serve as ground truth for training and evaluation.
  • Findingown data
    § Abstract · p. 1

    The proposed network outperforms total variation-regularized iterative reconstruction for the more realistic phantoms.

    “The proposed network outperforms total variation-regularized iterative reconstruction for the more realistic phantoms”
    Quote in the paperSubstantial claim
    • Rests on an assumption: High-view FBP reconstructions can serve as ground truth for training and evaluation.
  • May combine two claims. 20
  • Classified as probably not a substantial claim. 8
  • May combine two claims.

    Findingown data
    § A. Ellipsoidal Dataset · p. 12

    For the ellipsoidal dataset at 50 views, the average SNR was 8.44 dB for FBP, 27.69 dB for TV, and 23.84 dB for FBPConvNet.

    “| avg. SNR (dB) | 50 views (x20) | 8.44 | 27.69 | 23.84 |”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The training and test sets for the synthetic datasets are disjoint.
  • May combine two claims.

    Findingown data
    § A. Ellipsoidal Dataset · p. 11

    For the ellipsoidal dataset at 143 views, the full-view FBP shows nearly artifact-free ellipsoids, while the sparse-view FBP shows significant line artifacts.

    “In the seven times downsampling case, Figure 3, the full-view FBP (ground truth) shows nearly artifact-free ellipsoids, while the sparseview FBP shows significant line artifacts (most visible in the background).”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The training and test sets for the synthetic datasets are disjoint.
  • May combine two claims.

    Findingown data
    § A. Ellipsoidal Dataset · p. 12

    For the ellipsoidal dataset at 143 views, the average SNR was 16.09 dB for FBP, 29.48 dB for TV, and 28.96 dB for FBPConvNet.

    “| avg. SNR (dB) | 143 views (x7) | 16.09 | 29.48 | 28.96 |”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The training and test sets for the synthetic datasets are disjoint.
  • May combine two claims.

    Findingown data
    § A. Ellipsoidal Dataset · p. 11

    For the ellipsoidal dataset at 20x downsampling, both the TV and FBPConvNet reduce these artifacts, though the FBPConvNet retains some of the artifacts.

    “Both the TV and FBPConvNet reduce these artifacts, though the FBPConvNet retains some of the artifacts.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: The training and test sets for the synthetic datasets are disjoint.
  • Classified as probably not a substantial claim.

    Findingreasoning
    § C. Iterative Inversion · p. 6

    When the forward model is normal-convolutional and W is a convolution, ISTA consists of iteratively filtering by I-(1/L)W*H*HW, adding a bias (1/L)W*H*y, and applying a point-wise nonlinearity S_θ.

    “When the forward model is normal-convolutional and when W is a convolution, the algorithm consists of iteratively filtering by I -(1 /L ) W ∗ H ∗ HW , adding a bias, (1 /L ) W ∗ H ∗ y , and applying a point-wise nonlinearity, S θ .”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingown data
    § B. Biomedical Dataset · p. 13

    For the biomedical dataset at 50 views, the average SNR was 13.52 dB for FBP, 25.2 dB for TV, and 28.83 dB for FBPConvNet.

    “| avg. SNR (dB) | 50 views (x20) | 13.52 | 25.2 | 28.83 |”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingown data
    § C. Experimental Dataset · p. 15

    For the experimental dataset, the same trend as for the biomedical dataset is observed, where the TV method oversmooths and the FBPConvNet better preserves fine structures.

    “In Fig. 7, we observe the same trend as for the biomedical dataset, where the TV method oversmooths and the FBPConvNet better preserves fine structures.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingown data
    § VI. DISCUSSION · p. 16

    The FBPConvNet computation time is much faster than the iterative reconstruction, which requires around 7 minutes even after the regularization parameters have been selected.

    “This is much faster than the iterative reconstruction, which, in our case, requires around 7 minutes even after the regularization parameters have been selected.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S4 (based).

    Findingnone given
    § VII. CONCLUSION · p. 17

    After training, the computation time of the proposed network per one image is under a second.

    “Furthermore, after training, the computation time of the proposed network per one image is under a second.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingown data
    § VI. DISCUSSION · p. 16

    The conventional iterative algorithm with TV regularization outperformed the FBPConvNet in the ellipsoidal dataset, while the reverse was true for the biomedical and experimental datasets.

    “The conventional iterative algorithm with TV regularization outperformed the FBPConvNet in the ellipsoidal dataset, while the reverse was true for the biomedical and experimental datasets.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingown data
    § B. Biomedical Dataset · p. 15

    For the experimental dataset at 145 views, the average SNR was 5.38 dB for FBP, 8.25 dB for TV, and 11.34 dB for FBPConvNet.

    “| avg. SNR (dB) | 145 views (x5) | 5.38 | 8.25 | 11.34 |”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingown data
    § B. Biomedical Dataset · p. 13

    For the biomedical dataset at 143 views, the average SNR was 24.97 dB for FBP, 31.92 dB for TV, and 36.15 dB for FBPConvNet.

    “| avg. SNR (dB) | 143 views (x7) 24.97 | | 31.92 36.15 | |”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingown data
    § B. Biomedical Dataset · p. 13

    For the biomedical dataset, both TV and the proposed method remove streaking artifacts satisfactorily; however, the TV reconstruction shows cartoon-like artifacts typical of TV reconstructions.

    “Both TV and the proposed method remove streaking artifacts satisfactorily; however, the TV reconstruction shows the cartoon-like artifacts that are typical of TV reconstructions.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingown data
    § B. Biomedical Dataset · p. 15

    For the experimental dataset at 51 views, the average SNR was 3.29 dB for FBP, 7.25 dB for TV, and 8.85 dB for FBPConvNet.

    “| avg. SNR (dB) | 51 views (x14) | 3.29 | 7.25 | 8.85 |”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingown data
    § VI. DISCUSSION · p. 16

    The computation time for the FBPConvNet was about 200 ms for the FBP and 200 ∼ 300 ms in GPU for the CNN for a 512 × 512 image.

    “The computation time for the FBPConvNet was about 200 ms for the FBP and 200 ∼ 300 ms in GPU for the CNN for a 512 × 512 image.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Interpretationreasoning
    § A. Filtered Back Projection · p. 7

    In CT reconstruction, if the sinogram is used as input, the CNN must encode a change between polar and Cartesian coordinates, which is completely avoided when the FBP is used as input.

    “For example, in the case of CT reconstruction, if the sinogram is used as input, the CNN must encode a change between polar and Cartesian coordinates, which is completely avoided when the FBP is used as input.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Study design and conductreasoning
    § I. INTRODUCTION · p. 3

    Training is possible from real data without oracle knowledge because high-view FBP reconstructions are used for training.

    “We use high-view FBP reconstructions for training, meaning that training is possible from real data (without oracle knowledge).”
    Quote in the paperSubstantial claim
    • Rests on an assumption: High-view FBP reconstructions can serve as ground truth for training and evaluation.
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation
    § B. Training Procedure · p. 10

    The FBPConvNet training clips the computed gradients to a fixed range to prevent the divergence of the cost function.

    “We clip the computed gradients to a fixed range to prevent the divergence of the cost function [27], [46].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [27] [27] J. Kim, J. K. Lee, and K. M. Lee, 'Accurate image super-resolution using very deep convolutional networks,' in Proc. of IEEE Converence on Computer Vision and Pattern Recognition (CVPR) , 2016. - source

      Not checked in the free run.

    • cites [46] [46] R. Pascanu, T. Mikolov, and Y. Bengio, 'On the difficulty of training recurrent neural networks.' ICML (3) , vol. 28, pp. 1310-1318, 2013. - source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation
    § B. Training Procedure · p. 10

    The FBPConvNet training uses flip-flop data augmentation in both horizontal and vertical directions to reduce overfitting.

    “We use flip-flop data augmentation in both horizontal and vertical directions during the training phase to reduce overfitting [18].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [18] [18] A. Krizhevsky, I. Sutskever, and G. E. Hinton, 'Imagenet classification with deep convolutional neural networks,' in Advances in neural information processing systems , 2012, pp. 1097-1105. -

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § C. Iterative Inversion · p. 6

    Many other iterative methods for solving Eq. (5), including ADMM, FISTA, and SALSA, also rely on these basic building blocks.

    “Many other iterate methods for solving Eq. (5), including ADMM [40], FISTA [41], and SALSA [42], also rely on these basic building blocks.”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [40] [40] S. Boyd, N. Parikh, E. Chu, B. Peleato, and J. Eckstein, 'Distributed optimization and statistical learning via the alternating direction method of multipliers,' Found. Trends in Mach. Learn. , vol. 3, no. 1, pp. 1-122, 2011. -

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites [41] [41] A. Beck and M. Teboulle, 'A fast iterative shrinkage-thresholding algorithm for linear inverse problems,' SIAM journal on imaging sciences , vol. 2, no. 1, pp. 183-202, 2009. - source

      Not checked in the free run.

    • cites [42] [42] M. V. Afonso, J. M. Bioucas-Dias, and M. A. Figueiredo, 'Fast image recovery using variable splitting and constrained optimization,' IEEE Transactions on Image Processing , vol. 19, no. 9, pp. 2345-2356, 2010. - source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given
    § B. Training Procedure · p. 10

    For the biomedical dataset, the test data is chosen from a different subject than the training set.

    “In the case of the biomedical dataset, the test data is chosen from a different subject than the training set.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning
    § B. Training Procedure · p. 10

    The TV method's parameters were selected by optimizing performance on the training set via a golden-section search.

    “we instead simply select the parameters that optimize performance on the training set (via a golden-section search).”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation
    § I. INTRODUCTION · p. 3

    The class of normal-convolutional inverse problems includes denoising, deconvolution, MRI, X-ray CT, and diffraction tomography.

    “The class trivially includes denoising and deconvolution, but also includes MRI [35], X-ray CT [13], [16], and diffraction tomography (DT).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [35] [35] K. P. Pruessmann, M. Weiger, M. B. Scheidegger, P. Boesiger et al. , 'SENSE: sensitivity encoding for fast MRI,' Magn. Reson. Med. , vol. 42, no. 5, pp. 952-962, 1999. -

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites [13] [13] M. T. McCann, M. Nilchian, M. Stampanoni, and M. Unser, 'Fast 3D reconstruction method for differential phase contrast X-ray CT,' Opt. Express , vol. 24, no. 13, pp. 14 564-14 581, Jun 2016. - source

      Not checked in the free run.

    • cites [16] [16] E. Y. Sidky and X. Pan, 'Image reconstruction in circular cone-beam computed tomography by constrained, total-variation minimization,' Physics in medicine and biology , vol. 53, no. 17, p. 4777, 2008. - source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation
    § C. Iterative Inversion · p. 6

    In practice, inverse problems related with imaging are often ill-posed, which prohibits direct inversion because measurement noise causes severe perturbations in the solution.

    “In practice, inverse problems related with imaging are often ill-posed, which prohibits the use of direct inversion because measurement noise causes serve perturbations in the solution.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [2] [2] A. Chambolle, 'An algorithm for total variation minimization and applications,' J. Math. imaging and vision , vol. 20, no. 1-2, pp. 89-97, 2004. - source

      Not checked in the free run.

    • cites [9] [9] R. Tibshirani, 'Regression shrinkage and selection via the lasso,' Journal of the Royal Statistical Society. Series B (Methodological) , pp. 267-288, 1996. - source

      Not checked in the free run.

  • May combine two claims.

    Premisenone given
    § C. Iterative Inversion · p. 6

    The synthesis formulation of the inverse problem does not admit a closed form solution and is typically solved iteratively.

    “This formulation does not admit a closed form solution, and, therefore, is typically solved iteratively.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Interpretationreasoning
    § Skip connection · p. 8

    The U-net's multilevel decomposition is critical for the application because the filters corresponding to H*H (and its inverse) may have noncompact support, e.g. in CT; thus a CNN with a small, fixed filter size may not be able to effectively invert H*H.

    “This is critical for our application because the filters corresponding to H ∗ H (and its inverse) may have noncompact support, e.g. in CT. Thus, a CNN with a small, fixed filter size may not be able to effectively invert H ∗ H .”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given
    § B. Training Procedure · p. 10

    For the real data, the test data are obtained from the last z-slices with a gap of 25 slices left between testing and training data.

    “The test data are obtained from the last z-slices with the gap of 25 slices left between testing and training data.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Interpretationreasoning
    § VI. DISCUSSION · p. 16

    One advantage of the proposed method over iterative methods is that the iterative methods must explicitly impose regularization, while the FBPConvNet effectively learns a regularizer from the data.

    “This points to one advantage of the proposed method over iterative methods: the iterative methods must explicitly impose regularization, while the FBPConvNet effectively learns a regularizer from the data.”
    Quote in the paperSubstantial claim
28 of 28
  • The paper relies on this without support.

    High-view FBP reconstructions can serve as ground truth for training and evaluation.

    “We compute its FBP (standard high quality reconstruction) and take this as the ground truth.”
  • The paper relies on this without support.

    A twenty times reduction in the number of views corresponds to a twenty times reduction in the radiation dose received by the patient.

    “a twenty times reduction in the number of views corresponds to a twenty times reduction in the radiation dose received by the patient.”
  • The paper relies on this without support.

    The training and test sets for the synthetic datasets are disjoint.

    “In case of synthetic data, the total number of training images is 475. The number of test images is 25.”
3 of 3

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • U-net could effectively produce noiseless CT images from the subsampled sinogram.

    “Their study showed that U-net could effectively produce noiseless CT images from the subsampled sinogram.”

    From Convolutional neural networks: an overview and application in radiology (2018) · cites this paper as [54]

    The Experiments and Results section (p. 9) tests FBPConvNet on subsampled CT sinograms, and the Biomedical Dataset results (p. 13) report satisfactory removal of streaking artifacts and improved SNR. The network uses a modified U-net, but the paper does not claim its output is noiseless; the Discussion (p. 16) notes that artifacts can remain. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Experimental 14-fold case is reported as both 51 and 52 views

    Minor

    The data-preparation text says the 14-fold subsampling yields 52 views, but Table III labels that case as 51 views.

  • Experimental result is described as 20-fold rather than 14-fold downsampling

    Minor

    The discussion of Fig. 8 calls it a twenty-times downsampling case, whereas the experimental data-preparation text identifies the corresponding 52-view case as 14-fold downsampling.

2 of 2

Cites

Flagged first, then by citations

9 of the 83 references couldn’t be matched to a known paper.

Research works printed but not linked: 1

  1. epperson, 2013, Creation of fully sampled mr data repository for compressed sensing of the knee, Proc SMRT Conf

Cited by

Sorted by citations

Authors
Jin, K. H., McCann, M. T., Froustey, E., & Unser, M.
Affiliations
  • École Polytechnique Fédérale de Lausanne (CH)
  • Dassault Aviation (France) (FR)
Venue
IEEE Transactions on Image Processing
Published
2017-09
Volume
26
Issue
9
Pages
4509-4522
ISSN
  • 1057-7149 (ISSN-L)
  • 1941-0042
OpenAlex
W2574952845
Cited by
2,529
References
83
Citations by year
2026: 184 · 2025: 280 · 2024: 291 · 2023: 318 · 2022: 317 · 2021: 383 · 2020: 326 · 2019: 277 · 2018: 128 · 2017: 23 · 2016: 1 · 2012: 1
FWCI
228.23
Type
journal article
Language
en
Open access
Locations
  • IEEE Transactions on Image Processing (publishedVersion)
  • PubMed (publishedVersion)
  • arXiv (Cornell University) (submittedVersion)
  • DORA PSI (Paul Scherrer Institute) (submittedVersion)
  • Infoscience (Ecole Polytechnique Fédérale de Lausanne) (submittedVersion)
  • Infoscience (Ecole Polytechnique Fédérale de Lausanne) (submittedVersion, cc-by-nc-nd)
  • arXiv (Cornell University)
Funders
  • H2020 European Research Council (the European Research Council under Grant 692726 ()
  • Centre dImagerie BioMedicale
  • EPFL Fellows fellowship program co-funded by Marie Curie from the EuropeanUnions Horizon 2020 Framework Programme for Research and Innovation (665667)
Topics
  • Physical Sciences › Mathematics › Mathematical Physics › Numerical methods in inverse problems
  • Health Sciences › Medicine › Radiology, Nuclear Medicine and Imaging › Medical Imaging Techniques and Applications
  • Physical Sciences › Computer Science › Computer Vision and Pattern Recognition › Image and Signal Denoising Methods
Keywords
deep convolutional neural networks, ill-posed inverse problems, direct inversion, artifact removal, multiresolution decomposition, residual learning, sparse-view reconstruction, total variation regularization, image reconstruction

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