Anatomical shape analysis plays a pivotal role in clinical research and hypothesis testing, where the relationship between form and function is paramount. Correspondence-based statistical shape modeling (SSM) facilitates population-level morphometrics but requires a cumbersome, potentially bias-inducing construction pipeline. Recent advancements in deep learning have streamlined this process in inference by providing SSM prediction directly from unsegmented medical images. However, the proposed approaches are fully supervised and require utilizing a traditional SSM construction pipeline to create training data, thus inheriting the associated burdens and limitations. To address these challenges, we introduce a weakly supervised deep learning approach to predict SSM from images using point cloud supervision. Specifically, we propose reducing the supervision associated with the state-of-the-art fully Bayesian variational information bottleneck DeepSSM (BVIB-DeepSSM) model. BVIB-DeepSSM is an effective, principled framework for predicting probabilistic anatomical shapes from images with quantification of both aleatoric and epistemic uncertainties. Whereas the original BVIB-DeepSSM method requires strong supervision in the form of ground truth correspondence points, the proposed approach utilizes weak supervision via point cloud surface representations, which are more readily obtainable. Furthermore, the proposed approach learns correspondence in a completely data-driven manner without prior assumptions about the expected variability in shape cohort. Our experiments demonstrate that this approach yields similar accuracy and uncertainty estimation to the fully supervised scenario while substantially enhancing the feasibility of model training for SSM construction.
In medical imaging, Class-Activation Map (CAM) serves as the main explainability tool by pointing to the region of interest. Since the localization accuracy from CAM is constrained by the resolution of the model's feature map, one may expect that segmentation models, which generally have large feature maps, would produce more accurate CAMs. However, we have found that this is not the case due to task mismatch. While segmentation models are developed for datasets with pixel-level annotation, only image-level annotation is available in most medical imaging datasets. Our experiments suggest that …
Hangzhou Dianzi University(杭州电子科技大学);Zhejiang University of Science and Technology(浙江科技学院)
Weakly-supervised learning has become a popular technology in recent years. In this paper, we propose a novel medical image classification algorithm, called Weakly-Supervised Generative Adversarial Networks (WSGAN), which only uses a small number of real images without labels to generate fake images or mask images to enlarge the sample size of the training set. First, we combine with MixMatch to generate pseudo labels for the fake images and unlabeled images to do the classification. Second, contrastive learning and self-attention mechanism are introduced into the proposed problem to enhance t…
SimTxtSeg: Weakly-Supervised Medical Image Segmentation with Simple Text Cues
School of Computer Science and Engineering, Southeast University(东南大学计算机科学与工程学院);Key Laboratory of New Generation Artificial Intelligence Technology and Its Interdisciplinary Applications, Ministry of Education, China(教育部新一代人工智能技术及交叉应用重点实验室);Nanjing University of Science and Technology(南京理工大学);Northwestern Polytechnical University(西北工业大学)
University of Haifa(海法大学);IBM Research(IBM研究院);Bar-Ilan University(巴伊兰大学)
This study presents a novel deep learning architecture for multi-class classification and localization of abnormalities in medical imaging illustrated through experiments on mammograms. The proposed network combines two learning branches. One branch is for region classification with a newly added normal-region class. Second branch is region detection branch for ranking regions relative to one another. Our method enables detection of abnormalities at full mammogram resolution for both weakly and semi-supervised settings. A novel objective function allows for the incorporation of local annotatio…
Annotation of medical images has been a major bottleneck for the development of accurate and robust machine learning models. Annotation is costly and time-consuming and typically requires expert knowledge, especially in the medical domain. Here, we propose to use minimal user interaction in the form of extreme point clicks in order to train a segmentation model that can, in turn, be used to speed up the annotation of medical images. We use extreme points in each dimension of a 3D medical image to constrain an initial segmentation based on the random walker algorithm. This segmentation is then …
University of Guelph(圭尔夫大学);Vector Institute(向量研究所)
In Digital Pathology (DP), labeled data is generally very scarce due to the requirement that medical experts provide annotations. We address this issue by learning transferable features from weakly labeled data, which are collected from various parts of the body and are organized by non-medical experts. In this paper, we show that features learned from such weakly labeled datasets are indeed transferable and allow us to achieve highly competitive patch classification results on the colorectal cancer (CRC) dataset [1] and the PatchCamelyon (PCam) dataset [2] while using an order of magnitude le…
CmFNet: Cross-modal Fusion Network for Weakly-supervised Segmentation of Medical Images
School of Physics, Peking University(北京大学物理学院);School of Computer Science, Peking University(北京大学计算机学院);Department of Radiotherapy, Peking University Cancer Hospital(北京大学肿瘤医院放疗科);Department of Radiation Oncology, Peking University Third Hospital(北京大学第三医院放疗科)
DExTeR: Weakly Semi-Supervised Object Detection with Class and Instance Experts for Medical Imaging
University of Strasbourg, CNRS, INSERM, ICube, UMR7357, France(斯特拉斯堡大学、法国国家科学研究中心、法国国家医学研究院、ICube、UMR7357、法国);University Hospital of Strasbourg, France(斯特拉斯堡大学医院、法国)
The University of Sheffield(谢菲尔德大学);University of East Anglia(东英吉利大学)
Magnetic Resonance Imaging (MRI) offers high-resolution \emph{in vivo} imaging and rich functional and anatomical multimodality tissue contrast. In practice, however, there are challenges associated with considerations of scanning costs, patient comfort, and scanning time that constrain how much data can be acquired in clinical or research studies. In this paper, we explore the possibility of generating high-resolution and multimodal images from low-resolution single-modality imagery. We propose the weakly-supervised joint convolutional sparse coding to simultaneously solve the problems of sup…
Weakly Supervised Medical Image Segmentation With Soft Labels and Noise Robust Loss
University of Calgary(卡尔加里大学);McCaig Institute for Bone and Joint Health(麦凯格骨骼与关节健康研究所);University of Alberta(阿尔伯塔大学);Alberta Machine Intelligence Institute (AMII)(阿尔伯塔机器智能研究所)
Southeast University(东南大学);Centre de Recherche en Information Biomédicale Sino-Français (CRIBs)(中法生物医学信息研究中心);Univ Rennes(雷恩大学);Inserm(法国国家健康与医学研究院);LTSI - UMR1099(信号与图像处理实验室)
Deep learning-based medical image registration and segmentation joint models utilize the complementarity (augmentation data or weakly supervised data from registration, region constraints from segmentation) to bring mutual improvement in complex scene and few-shot situation. However, further adoption of the joint models are hindered: 1) the diversity of augmentation data is reduced limiting the further enhancement of segmentation, 2) misaligned regions in weakly supervised data disturb the training process, 3) lack of label-based region constraints in few-shot situation limits the registration…
Shanghai Jiaotong University(上海交通大学);Shanghai AI Lab(上海人工智能实验室);University of Electronic Science and Technology of China(电子科技大学);Sensetime Research(商汤科技研究院)
Deep neural networks usually require accurate and a large number of annotations to achieve outstanding performance in medical image segmentation. One-shot segmentation and weakly-supervised learning are promising research directions that lower labeling effort by learning a new class from only one annotated image and utilizing coarse labels instead, respectively. Previous works usually fail to leverage the anatomical structure and suffer from class imbalance and low contrast problems. Hence, we present an innovative framework for 3D medical image segmentation with one-shot and weakly-supervised…
Hispathological image segmentation algorithms play a critical role in computer aided diagnosis technology. The development of weakly supervised segmentation algorithm alleviates the problem of medical image annotation that it is time-consuming and labor-intensive. As a subset of weakly supervised learning, Multiple Instance Learning (MIL) has been proven to be effective in segmentation. However, there is a lack of related information between instances in MIL, which limits the further improvement of segmentation performance. In this paper, we propose a novel weakly supervised method for pixel-l…
Recent advances of deep learning have achieved remarkable performances in various challenging computer vision tasks. Especially in object localization, deep convolutional neural networks outperform traditional approaches based on extraction of data/task-driven features instead of hand-crafted features. Although location information of region-of-interests (ROIs) gives good prior for object localization, it requires heavy annotation efforts from human resources. Thus a weakly supervised framework for object localization is introduced. The term "weakly" means that this framework only uses image-l…
Robert Bosch GmbH(罗伯特·博世有限公司);TU Dortmund University(多特蒙德工业大学);Max Planck Institute for Intelligent Systems(马克斯·普朗克智能系统研究所)
Convolutional neural networks (CNNs) show impressive performance for image classification and detection, extending heavily to the medical image domain. Nevertheless, medical experts are sceptical in these predictions as the nonlinear multilayer structure resulting in a classification outcome is not directly graspable. Recently, approaches have been shown which help the user to understand the discriminative regions within an image which are decisive for the CNN to conclude to a certain class. Although these approaches could help to build trust in the CNNs predictions, they are only slightly sho…
TWLR: Text-Guided Weakly-Supervised Lesion Localization and Severity Regression for Explainable Diabetic Retinopathy Grading
Guangdong Provincial Key Laboratory of Interdisciplinary Research and Application for Data Science(广东省级交叉学科研究与数据科学应用重点实验室);Department of Statistics and Data Science, Beijing Normal-Hong Kong Baptist University(北京师范大学-香港 Baptist大学统计与数据科学系);Faculty of Science, Hong Kong Baptist University(香港 Baptist大学科学学院);Data Science Research Center, Duke Kunshan University(杜克-昆山大学数据科学研究中心);Shanxi Provincial People’s Hospital(山西人民医院);The Fifth Clinical Medical school of Shanxi Medical University(山西医科大学第五临床医学院);Research Center for Mathematics, Beijing Normal University(北京师范大学数学研究中心);Department of Mathematics and Statistics, York University(约克大学数学与统计学系)
Neural Cellular Automata for Weakly Supervised Segmentation of White Blood Cells
Institute of AI for Health, Helmholtz Zentrum München – German Research Center for Environmental Health(人工智能与健康研究所,慕尼黑德国环境健康研究中心);TUM School of Computation, Information and Technology, Technical University Munich(技术大学慕尼黑计算、信息与技术学院);Institute of Chemical Epigenetics, Faculty of Chemistry and Pharmacy, Ludwig Maximilian University(化学表观遗传学研究所,路德维希-马克西米利安大学);Computer Aided Medical Procedures, Technical University of Munich(医学辅助程序研究所,技术大学慕尼黑)
School of Information Science and Technology, ShanghaiTech University(上海科技大学信息科学与技术学院);Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences(中国科学院上海微系统与信息技术研究所);University of Chinese Academy of Sciences(中国科学院大学);Shanghai Engineering Research Center of Intelligent Vision and Imaging(上海智能视觉与成像工程技术研究中心)
Weakly supervised segmentation is an important problem in medical image analysis due to the high cost of pixelwise annotation. Prior methods, while often focusing on weak labels of 2D images, exploit few structural cues of volumetric medical images. To address this, we propose a novel weakly-supervised segmentation strategy capable of better capturing 3D shape prior in both model prediction and learning. Our main idea is to extract a self-taught shape representation by leveraging weak labels, and then integrate this representation into segmentation prediction for shape refinement. To this end,…
Interpretability of deep learning (DL) systems is gaining attention in medical imaging to increase experts' trust in the obtained predictions and facilitate their integration in clinical settings. We propose a deep visualization method to generate interpretability of DL classification tasks in medical imaging by means of visual evidence augmentation. The proposed method iteratively unveils abnormalities based on the prediction of a classifier trained only with image-level labels. For each image, initial visual evidence of the prediction is extracted with a given visual attribution technique. T…
ToNNO: Tomographic Reconstruction of a Neural Network's Output for Weakly Supervised Segmentation of 3D Medical Images
TheraPanacea;University of Crete(克里特大学);IACM, FORTH(FORTH 应用与计算数学研究所);Archimedes, Athena RC(雅典研究中心阿基米德研究所);CentraleSupélec, University of Paris-Saclay(中央理工-高等电力学院,巴黎-萨克雷大学)
Kyushu University(九州大学);Kyoto University(京都大学);The University of Tokyo(东京大学)
Semi-supervised domain adaptation is a technique to build a classifier for a target domain by modifying a classifier in another (source) domain using many unlabeled samples and a small number of labeled samples from the target domain. In this paper, we develop a semi-supervised domain adaptation method, which has robustness to class-imbalanced situations, which are common in medical image classification tasks. For robustness, we propose a weakly-supervised clustering pipeline to obtain high-purity clusters and utilize the clusters in representation learning for domain adaptation. The proposed …
On-the-Fly Guidance Training for Medical Image Registration
University of Leeds(利兹大学);University of California, Irvine(加州大学欧文分校);Tongji University(同济大学);Huazhong University of Science and Technology(华中科技大学);Fudan Univeristy(复旦大学);University of California, San Diego(加州大学圣迭戈分校)
Deep Convolutional Neural Networks have proven effective in solving the task of semantic segmentation. However, their efficiency heavily relies on the pixel-level annotations that are expensive to get and often require domain expertise, especially in medical imaging. Weakly supervised semantic segmentation helps to overcome these issues and also provides explainable deep learning models. In this paper, we propose a novel approach to the semantic segmentation of medical chest X-ray images with only image-level class labels as supervision. We improve the disease localization accuracy by combinin…
SAM-Driven Weakly Supervised Nodule Segmentation with Uncertainty-Aware Cross Teaching
School of Software Engineering, Xi’an Jiaotong University(西安交通大学软件学院);University of Electronic Science and Technology of China(电子科技大学);Shanghai Artificial Intelligence Laboratory(上海人工智能实验室);Xiangya Hospital, Central South University(中南大学湘雅医院);Hunan Frontline Medical Technology Co., Ltd(湖南前沿医疗科技有限公司)
An efficient strategy for weakly-supervised segmentation is to impose constraints or regularization priors on target regions. Recent efforts have focused on incorporating such constraints in the training of convolutional neural networks (CNN), however this has so far been done within a continuous optimization framework. Yet, various segmentation constraints and regularization can be modeled and optimized more efficiently in a discrete formulation. This paper proposes a method, based on the alternating direction method of multipliers (ADMM) algorithm, to train a CNN with discrete constraints an…
LNQ 2023 challenge: Benchmark of weakly-supervised techniques for mediastinal lymph node quantification
Brigham and Women’s Hospital(布莱根妇女医院);Harvard Medical School(哈佛医学院);Massachusetts General Hospital(麻省总医院);Yunu, Inc.(尤努公司);Isomics Inc(伊索米克斯公司);Dana-Farber Cancer Institute(丹娜法伯癌症研究院);Technical University Munich(慕尼黑工业大学);Helmholtz Munich(慕尼黑亥姆霍兹中心);Munich Center of Machine Learning (MCML)(慕尼黑机器学习中心);King’s College London(伦敦国王学院);University of Lübeck(吕贝克大学);German Research Center for Artificial Intelligence(德国人工智能研究中心);Niigata University of Health and Welfare(新潟医疗福祉大学);Muroran Institute of Technology(室兰工业大学);Shanghai Jiao Tong University(上海交通大学);University of Electronic Science and Technology of China(电子科技大学);German Cancer Research Center (DKFZ)(德国癌症研究中心);University of Heidelberg(海德堡大学);Shanghai AI laboratory(上海人工智能实验室)
Case Western Reserve University(凯斯西储大学);IBM Almaden Research Center(IBM阿尔马登研究中心)
We explore a solution for learning disease signatures from weakly, yet easily obtainable, annotated volumetric medical imaging data by analyzing 3D volumes as a sequence of 2D images. We demonstrate the performance of our solution in the detection of emphysema in lung cancer screening low-dose CT images. Our approach utilizes convolutional long short-term memory (LSTM) to "scan" sequentially through an imaging volume for the presence of disease in a portion of scanned region. This framework allowed effective learning given only volumetric images and binary disease labels, thus enabling trainin…
University of California, Irvine(加州大学欧文分校);Lenovo AI Lab(联想人工智能实验室)
Recently deep learning has been witnessing widespread adoption in various medical image applications. However, training complex deep neural nets requires large-scale datasets labeled with ground truth, which are often unavailable in many medical image domains. For instance, to train a deep neural net to detect pulmonary nodules in lung computed tomography (CT) images, current practice is to manually label nodule locations and sizes in many CT images to construct a sufficiently large training dataset, which is costly and difficult to scale. On the other hand, electronic medical records (EMR) co…
The University of Texas at Austin(德克萨斯大学奥斯汀分校);Weill Cornell Medical College(威尔康奈尔医学院)
Before the recent success of deep learning methods for automated medical image analysis, practitioners used handcrafted radiomic features to quantitatively describe local patches of medical images. However, extracting discriminative radiomic features relies on accurate pathology localization, which is difficult to acquire in real-world settings. Despite advances in disease classification and localization from chest X-rays, many approaches fail to incorporate clinically-informed domain knowledge. For these reasons, we propose a Radiomics-Guided Transformer (RGT) that fuses \textit{global} image…
Carnegie Mellon University(卡内基梅隆大学);University of Pennsylvania(宾夕法尼亚大学)
We present a weakly supervised deep learning model for classifying thoracic diseases and identifying abnormalities in chest radiography. In this work, instead of learning from medical imaging data with region-level annotations, our model was merely trained on imaging data with image-level labels to classify diseases, and is able to identify abnormal image regions simultaneously. Our model consists of a customized pooling structure and an adaptive DenseNet front-end, which can effectively recognize possible disease features for classification and localization tasks. Our method has been validate…
Imperial College London(伦敦帝国学院);Aichi Cancer Center(爱知县癌症中心);Nagoya University(名古屋大学)
To efficiently establish training databases for machine learning methods, collaborative and crowdsourcing platforms have been investigated to collectively tackle the annotation effort. However, when this concept is ported to the medical imaging domain, reading expertise will have a direct impact on the annotation accuracy. In this study, we examine the impact of expertise and the amount of available annotations on the accuracy outcome of a liver segmentation problem in an abdominal computed tomography (CT) image database. In controlled experiments, we study this impact for different types of w…
The University of Adelaide(阿德莱德大学);Australian Institute for Machine Learning(澳大利亚机器学习研究所);Delft University of Technology(代尔夫特理工大学);Queensland University of Technology(昆士兰科技大学)
There is a heated debate on how to interpret the decisions provided by deep learning models (DLM), where the main approaches rely on the visualization of salient regions to interpret the DLM classification process. However, these approaches generally fail to satisfy three conditions for the problem of lesion detection from medical images: 1) for images with lesions, all salient regions should represent lesions, 2) for images containing no lesions, no salient region should be produced,and 3) lesions are generally small with relatively smooth borders. We propose a new model-agnostic paradigm to …
FMaMIL: Frequency-Driven Mamba Multi-Instance Learning for Weakly Supervised Lesion Segmentation in Medical Images
College of Computer Science and Technology (College of Data Science), Taiyuan University of Technology, Taiyuan, Shanxi, 030024, China(计算机科学与技术学院(数据科学学院),太原科技大学,太原,山西,030024,中国);College of Artificial Intelligence, Taiyuan University of Technology, Taiyuan, Shanxi, 030024, China(人工智能学院,太原科技大学,太原,山西,030024,中国);School of mathematics, Taiyuan University of Technology, Taiyuan, 030024, China(数学学院,太原科技大学,太原,030024,中国);School of Artificial Intelligence, Beijing Normal University, Beijing, 100875, China(人工智能学院,北京师范大学,北京,100875,中国);National Institute for Data Science in Health(健康数据科学国家研究院);the Department of Computer Science, School of Informatics, Xiammen, 361005, China(信息学院计算机科学系,厦门,361005,中国);School of Software, Dalian University of Technology, Dalian,116621, China(软件学院,大连理工大学,大连,116621,中国)
Skip and Skip: Segmenting Medical Images with Prompts
Academy for Engineering and Technology, Fudan University(复旦大学工程与技术学院);Engineering Research Center of AI and Robotics, Ministry of Education, China(教育部人工智能与机器人工程研究中心);Jilin Provincial Key Laboratory of Intelligence Science(吉林省智能科学重点实验室)
MILA(蒙特利尔学习算法研究所);Université de Montréal(蒙特利尔大学);Imagia Inc.(Imagia公司);School of Computing Science, Simon Fraser University(西蒙弗雷泽大学计算科学学院)
The scarcity of richly annotated medical images is limiting supervised deep learning based solutions to medical image analysis tasks, such as localizing discriminatory radiomic disease signatures. Therefore, it is desirable to leverage unsupervised and weakly supervised models. Most recent weakly supervised localization methods apply attention maps or region proposals in a multiple instance learning formulation. While attention maps can be noisy, leading to erroneously highlighted regions, it is not simple to decide on an optimal window/bag size for multiple instance learning approaches. In th…
Lesion segmentation in medical imaging serves as an effective tool for assessing tumor sizes and monitoring changes in growth. However, not only is manual lesion segmentation time-consuming, but it is also expensive and requires expert radiologist knowledge. Therefore many hospitals rely on a loose substitute called response evaluation criteria in solid tumors (RECIST). Although these annotations are far from precise, they are widely used throughout hospitals and are found in their picture archiving and communication systems (PACS). Therefore, these annotations have the potential to serve as a…
University of Electronic Science and Technology of China(电子科技大学);Shanghai Artificial Intelligence Laboratory(上海人工智能实验室);Johns Hopkins University(约翰斯·霍普金斯大学);West China Hospital, Sichuan University(四川大学华西医院)
Background and Objective: Open-source deep learning toolkits are one of the driving forces for developing medical image segmentation models. Existing toolkits mainly focus on fully supervised segmentation and require full and accurate pixel-level annotations that are time-consuming and difficult to acquire for segmentation tasks, which makes learning from imperfect labels highly desired for reducing the annotation cost. We aim to develop a new deep learning toolkit to support annotation-efficient learning for medical image segmentation. Methods: Our proposed toolkit named PyMIC is a modular de…
Microsoft Research(微软研究院);TuSimple(图森未来);Baidu Research(百度研究院);Tencent Medical AI Labs(腾讯医疗AI实验室);PingAn Tech(平安科技)
Medical imaging is an essential tool in many areas of medical applications, used for both diagnosis and treatment. However, reading medical images and making diagnosis or treatment recommendations require specially trained medical specialists. The current practice of reading medical images is labor-intensive, time-consuming, costly, and error-prone. It would be more desirable to have a computer-aided system that can automatically make diagnosis and treatment recommendations. Recent advances in deep learning enable us to rethink the ways of clinician diagnosis based on medical images. In this t…
Tencent Jarvis Lab, Tencent(腾讯杰维斯实验室,腾讯);National University of Defense Technology(国防科技大学)
Primary angle closure glaucoma (PACG) is the leading cause of irreversible blindness among Asian people. Early detection of PACG is essential, so as to provide timely treatment and minimize the vision loss. In the clinical practice, PACG is diagnosed by analyzing the angle between the cornea and iris with anterior segment optical coherence tomography (AS-OCT). The rapid development of deep learning technologies provides the feasibility of building a computer-aided system for the fast and accurate segmentation of cornea and iris tissues. However, the application of deep learning methods in the …
The University of Texas at Austin(德克萨斯大学奥斯汀分校);Weill Cornell Medicine(威尔康奈尔医学院)
Deep neural networks (DNNs) have rapidly become a \textit{de facto} choice for medical image understanding tasks. However, DNNs are notoriously fragile to the class imbalance in image classification. We further point out that such imbalance fragility can be amplified when it comes to more sophisticated tasks such as pathology localization, as imbalances in such problems can have highly complex and often implicit forms of presence. For example, different pathology can have different sizes or colors (w.r.t.the background), different underlying demographic distributions, and in general different …
Low-Rank Velocity Fields as a Structural Prior for Unsupervised 4D Medical Image Interpolation
Southern University of Science and Technology(南方科技大学);Shenzhen University of Advanced Technology(深圳先进技术研究院);Shenzhen University Medical School(深圳大学医学院);Shenzhen University(深圳大学);Research Institute of Trustworthy Autonomous Systems(可信自主系统研究院)
We consider the problem of abnormality localization for clinical applications. While deep learning has driven much recent progress in medical imaging, many clinical challenges are not fully addressed, limiting its broader usage. While recent methods report high diagnostic accuracies, physicians have concerns trusting these algorithm results for diagnostic decision-making purposes because of a general lack of algorithm decision reasoning and interpretability. One potential way to address this problem is to further train these models to localize abnormalities in addition to just classifying them…
The Hospital for Sick Children(病童医院);University of Toronto(多伦多大学);Vector Institute(Vector研究所)
Deep convolutional neural networks (CNNs) have become an essential tool in the medical imaging-based computer-aided diagnostic pipeline. However, training accurate and reliable CNNs requires large fine-grain annotated datasets. To alleviate this, weakly-supervised methods can be used to obtain local information from global labels. This work proposes the use of localized perturbations as a weakly-supervised solution to extract segmentation masks of brain tumours from a pretrained 3D classification model. Furthermore, we propose a novel optimal perturbation method that exploits 3D superpixels to…