Siam, Mennatullah
Two-stage Joint Transductive and Inductive learning for Nuclei Segmentation
Ali, Hesham, Tondji, Idriss, Siam, Mennatullah
AI-assisted nuclei segmentation in histopathological images is a crucial task in the diagnosis and treatment of cancer diseases. It decreases the time required to manually screen microscopic tissue images and can resolve the conflict between pathologists during diagnosis. Deep Learning has proven useful in such a task. However, lack of labeled data is a significant barrier for deep learning-based approaches. In this study, we propose a novel approach to nuclei segmentation that leverages the available labelled and unlabelled data. The proposed method combines the strengths of both transductive and inductive learning, which have been previously attempted separately, into a single framework. Inductive learning aims at approximating the general function and generalizing to unseen test data, while transductive learning has the potential of leveraging the unlabelled test data to improve the classification. To the best of our knowledge, this is the first study to propose such a hybrid approach for medical image segmentation. Moreover, we propose a novel two-stage transductive inference scheme. We evaluate our approach on MoNuSeg benchmark to demonstrate the efficacy and potential of our method.
Adaptive Masked Weight Imprinting for Few-Shot Segmentation
Siam, Mennatullah, Oreshkin, Boris
Deep learning has mainly thrived by training on large-scale datasets. However, for a continual learning agent it is critical to incrementally update its model in a sample efficient manner. Learning semantic segmentation from few labelled samples can be a significant step toward such goal. We propose a novel method that constructs the new class weights from few labelled samples in the support set without back-propagation, while updating the previously learned classes. Inspiring from the work on adaptive correlation filters, an adaptive masked imprinted weights method is designed. It utilizes a masked average pooling layer on the output embeddings and acts as a positive proxy for that class. Our proposed method is evaluated on PASCAL-5i dataset and outperforms the state of the art in the 5-shot semantic segmentation. Unlike previous methods, our proposed approach does not require a second branch to estimate parameters or prototypes, and enables the adaptation of previously learned weights. Our adaptation scheme is evaluated on DAVIS video segmentation benchmark and our proposed incremental version of PASCAL and has shown to outperform the baseline model.
Deep Semantic Segmentation for Automated Driving: Taxonomy, Roadmap and Challenges
Siam, Mennatullah, Elkerdawy, Sara, Jagersand, Martin, Yogamani, Senthil
Semantic segmentation was seen as a challenging computer vision problem few years ago. Due to recent advancements in deep learning, relatively accurate solutions are now possible for its use in automated driving. In this paper, the semantic segmentation problem is explored from the perspective of automated driving. Most of the current semantic segmentation algorithms are designed for generic images and do not incorporate prior structure and end goal for automated driving. First, the paper begins with a generic taxonomic survey of semantic segmentation algorithms and then discusses how it fits in the context of automated driving. Second, the particular challenges of deploying it into a safety system which needs high level of accuracy and robustness are listed. Third, different alternatives instead of using an independent semantic segmentation module are explored. Finally, an empirical evaluation of various semantic segmentation architectures was performed on CamVid dataset in terms of accuracy and speed. This paper is a preliminary shorter version of a more detailed survey which is work in progress.