structural similarity index
Revolutionizing Brain Tumor Imaging: Generating Synthetic 3D FA Maps from T1-Weighted MRI using CycleGAN Models
Du, Xin, Cozzi, Francesca M., Jena, Rajesh
Fractional anisotropy (FA) and direction-ally encoded colour (DEC) maps are essential for evaluating white matter integrity and structural connectivity in neu-roimaging. However, the spatial misalignment between FA maps and tractog-raphy atlases hinders their effective integration into predictive models. To address this issue, we propose a CycleGAN-based approach for generating FA and DEC maps directly from T1-weighted MRI scans, representing the first application of this technique to both healthy and tumor-affected tissues. Our model, trained on unpaired data, produces high-fidelity maps, which have been rigorously evaluated using Structural Similarity Index (SSIM) and Peak Signal-to-Noise Ratio (PSNR), demonstrating particularly robust performance in tumour regions. Radiological assessments further underscore the model's potential to enhance clinical workflows by providing an AI-driven alternative that reduces the necessity for additional scans.
Advancing Agentic Systems: Dynamic Task Decomposition, Tool Integration and Evaluation using Novel Metrics and Dataset
Gabriel, Adrian Garret, Ahmad, Alaa Alameer, Jeyakumar, Shankar Kumar
Advancements in Large Language Models (LLMs) are revolutionizing the development of autonomous agentic systems by enabling dynamic, context-aware task decomposition and automated tool selection. These sophisticated systems possess significant automation potential across various industries, managing complex tasks, interacting with external systems to enhance knowledge, and executing actions independently. This paper presents three primary contributions to advance this field: - Advanced Agentic Framework: A system that handles multi-hop queries, generates and executes task graphs, selects appropriate tools, and adapts to real-time changes. - Novel Evaluation Metrics: Introduction of Node F1 Score, Structural Similarity Index (SSI), and Tool F1 Score to comprehensively assess agentic systems. - Specialized Dataset: Development of an AsyncHow-based dataset for analyzing agent behavior across different task complexities. Our findings reveal that asynchronous and dynamic task graph decomposition significantly enhances system responsiveness and scalability, particularly for complex, multi-step tasks. Detailed analysis shows that structural and node-level metrics are crucial for sequential tasks, while tool-related metrics are more important for parallel tasks. Specifically, the Structural Similarity Index (SSI) is the most significant predictor of performance in sequential tasks, and the Tool F1 Score is essential for parallel tasks. These insights highlight the need for balanced evaluation methods that capture both structural and operational dimensions of agentic systems. Additionally, our evaluation framework, validated through empirical analysis and statistical testing, provides valuable insights for improving the adaptability and reliability of agentic systems in dynamic environments.
Novel Change Detection Framework in Remote Sensing Imagery Using Diffusion Models and Structural Similarity Index (SSIM)
Kiruluta, Andrew, Lundy, Eric, Lemos, Andreas
Change detection is a crucial task in remote sensing, enabling the monitoring of environmental changes, urban growth, and disaster impact. Conventional change detection techniques, such as image differencing and ratioing, often struggle with noise and fail to capture complex variations in imagery. Recent advancements in machine learning, particularly generative models like diffusion models, offer new opportunities for enhancing change detection accuracy. In this paper, we propose a novel change detection framework that combines the strengths of Stable Diffusion models with the Structural Similarity Index (SSIM) to create robust and interpretable change maps. Our approach, named Diffusion Based Change Detector, is evaluated on both synthetic and real-world remote sensing datasets and compared with state-of-the-art methods. The results demonstrate that our method significantly outperforms traditional differencing techniques and recent deep learning-based methods, particularly in scenarios with complex changes and noise.
Speckle Noise Analysis for Synthetic Aperture Radar (SAR) Space Data
R, Sanjjushri Varshini, Mahadevan, Rohith, S, Bagiya Lakshmi, Periasamy, Mathivanan, Raman, Raja CSP, M, Lokesh
This research tackles the challenge of speckle noise in Synthetic Aperture Radar (SAR) space data, a prevalent issue that hampers the clarity and utility of SAR images. The study presents a comparative analysis of six distinct speckle noise reduction techniques: Lee Filtering, Frost Filtering, Kuan Filtering, Gaussian Filtering, Median Filtering, and Bilateral Filtering. These methods, selected for their unique approaches to noise reduction and image preservation, were applied to SAR datasets sourced from the Alaska Satellite Facility (ASF). The performance of each technique was evaluated using a comprehensive set of metrics, including Peak Signal-to-Noise Ratio (PSNR), Mean Squared Error (MSE), Structural Similarity Index (SSIM), Equivalent Number of Looks (ENL), and Speckle Suppression Index (SSI). The study concludes that both the Lee and Kuan Filters are effective, with the choice of filter depending on the specific application requirements for image quality and noise suppression. This work provides valuable insights into optimizing SAR image processing, with significant implications for remote sensing, environmental monitoring, and geological surveying.
Advancing Melanoma Diagnosis with Self-Supervised Neural Networks: Evaluating the Effectiveness of Different Techniques
Vusirikala, Srivishnu, Rajendran, Suraj
We investigate the potential of self-supervision in improving the accuracy of deep learning models trained to classify melanoma patches. Various self-supervision techniques such as rotation prediction, missing patch prediction, and corruption removal were implemented and assessed for their impact on the convolutional neural network's performance. Preliminary results suggest a positive influence of self-supervision methods on the model's accuracy. The study notably demonstrates the efficacy of the corruption removal method in enhancing model performance. Despite observable improvements, we conclude that the self-supervised models have considerable potential for further enhancement, achievable through training over more epochs or expanding the dataset. We suggest exploring other self-supervision methods like Bootstrap Your Own Latent (BYOL) and contrastive learning in future research, emphasizing the cost-benefit trade-off due to their resource-intensive nature. The findings underline the promise of self-supervision in augmenting melanoma detection capabilities of deep learning models.
Build an Image Duplicate Finder System: A Guide
To start with, I need to define an important term. A query image is an image the user enters to obtain information. With the help of a similarity block, the system searches for similar images among a dataset, which computes how close the images are to each other. Image 1 illustrates the steps. In section 3, we will be looking into this similarity block and exploring the most common methods of achieving this functionality.
Theoretical Insights into the Use of Structural Similarity Index In Generative Models and Inferential Autoencoders
Ghojogh, Benyamin, Karray, Fakhri, Crowley, Mark
Generative models and inferential autoencoders mostly make use of $\ell_2$ norm in their optimization objectives. In order to generate perceptually better images, this short paper theoretically discusses how to use Structural Similarity Index (SSIM) in generative models and inferential autoencoders. We first review SSIM, SSIM distance metrics, and SSIM kernel. We show that the SSIM kernel is a universal kernel and thus can be used in unconditional and conditional generated moment matching networks. Then, we explain how to use SSIM distance in variational and adversarial autoencoders and unconditional and conditional Generative Adversarial Networks (GANs). Finally, we propose to use SSIM distance rather than $\ell_2$ norm in least squares GAN.
Principal Component Analysis Using Structural Similarity Index for Images
Ghojogh, Benyamin, Karray, Fakhri, Crowley, Mark
Despite the advances of deep learning in specific tasks using images, the principled assessment of image fidelity and similarity is still a critical ability to develop. As it has been shown that Mean Squared Error (MSE) is insufficient for this task, other measures have been developed with one of the most effective being Structural Similarity Index (SSIM). Such measures can be used for subspace learning but existing methods in machine learning, such as Principal Component Analysis (PCA), are based on Euclidean distance or MSE and thus cannot properly capture the structural features of images. In this paper, we define an image structure subspace which discriminates different types of image distortions. We propose Image Structural Component Analysis (ISCA) and also kernel ISCA by using SSIM, rather than Euclidean distance, in the formulation of PCA. This paper provides a bridge between image quality assessment and manifold learning opening a broad new area for future research.