Segmentation of mammograms pertains to assigning a meaningful label to each pixel found in the image. The segmented mammogram facilitates both the function of Computer Aided Diagnosis Systems and the development of tools used by radiologists during examination. Over the years many approaches to this problem have been presented. A surge in the popularity of new methods to image processing involving deep neural networks present new possibilities in this domain, and this thesis evaluates mammogram segmentation as an application of a specialized neural network architecture, U-net. Results are produced on publicly available datasets mini-MIAS and CBIS-DDSM. Using these two datasets together with mammograms from Hologic and FUJI, instances of U-net are trained and evaluated within and across the different datasets. A total of 10 experiments are conducted using 4 different models. Averaged over classes Pectoral, Breast and Background the best Dice scores are: 0.987 for Hologic, 0.978 for FUJI, 0.967 for mini-MIAS and 0.971 for CBIS-DDSM.

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We use a Fully Convolutional Neural Network (FCNN) to classify pixels in historical document images, enabling the extraction of high-quality, pixel-precise and semantically consistent layers of masked content. We also analyze a dataset of hand-labeled historical form images of unprecedented detail and complexity. The semantic categories we consider in this new dataset include handwriting, machine-printed text, dotted and solid lines, and stamps. Segmentation of document images into distinct layers allows handwriting, machine print, and other content to be processed and recognized discriminatively, and therefore more intelligently than might be possible with content-unaware methods. We show that an efficient FCNN with relatively few parameters can accurately segment documents having similar textural content when trained on a single representative pixel-labeled document image, even when layouts differ significantly. In contrast to the overwhelming majority of existing semantic segmentation approaches, we allow multiple labels to be predicted per pixel location, which allows for direct prediction and reconstruction of overlapped content. We perform an analysis of prevalent pixel-wise performance measures, and show that several popular performance measures can be manipulated adversarially, yielding arbitrarily high measures based on the type of bias used to generate the ground-truth. We propose a solution to the gaming problem by comparing absolute performance to an estimated human level of performance. We also present results on a recent international competition requiring the automatic annotation of billions of pixels, in which our method took first place.

We use a Fully Convolutional Neural Network (FCNN) to classify pixels in historical document images, enabling the extraction of high-quality, pixel-precise and semantically consistent layers of masked content. We also analyze a dataset of hand-labeled historical form images of unprecedented detail and complexity. The semantic categories we consider in this new dataset include handwriting, machine-printed text, dotted and solid lines, and stamps. Segmentation of document images into distinct layers allows handwriting, machine print, and other content to be processed and recognized discriminatively, and therefore more intelligently than might be possible with content-unaware methods. We show that an efficient FCNN with relatively few parameters can accurately segment documents having similar textural content when trained on a single representative pixel-labeled document image, even when layouts differ significantly. In contrast to the overwhelming majority of existing semantic segmentation approaches, we allow multiple labels to be predicted per pixel location, which allows for direct prediction and reconstruction of overlapped content. We perform an analysis of prevalent pixel-wise performance measures, and show that several popular performance measures can be manipulated adversarially, yielding arbitrarily high measures based on the type of bias used to generate the ground-truth. We propose a solution to the gaming problem by comparing absolute performance to an estimated human level of performance. We also present results on a recent international competition requiring the automatic annotation of billions of pixels, in which our method took first place.

Identifying facemasks is an important duty that affects public health and safety, especially during epidemics of communicable diseases. Many architectures of deep learning models are being investigated for their effectiveness, as they have demonstrated great potential in automating this process. The performance of four well-known deep learning architectures—VGG19, VGG16, GRU, and Fully Convolutional Neural Networks (FCNN)—for facemask identification is thoroughly compared in this thesis. The goal of the study is to assess these architectures in terms of accuracy, efficiency, and robustness in order to offer important information for the creation of efficient facemask detection systems. This study examines the advantages and disadvantages of each model in relation to facemask detection through thorough testing and analysis. The models are statistically evaluated for their ability to detect facemasks in pictures or video streams using performance metrics including precision, recall, and F1-score. Furthermore, the actual feasibility of using these models in real-world applications is assessed by analyzing computational efficiency measures like inference time and model size. Moreover, the models' resilience is assessed in a range of demanding scenarios, such as changes in illumination, facial expressions, and occlusions. The consequences of these results are discussed in the thesis along with suggestions for improving each architecture for facemask detection tasks. This study's methodology focuses on developing and evaluating deep learning models for facemask recognition that are especially suited for usage in mobile health care units. This method seeks to guarantee high accuracy, robustness, and efficiency in real-world healthcare environments, where prompt and accurate facemask detection is essential. Four well-known deep learning architectures VGG19, VGG16, Gated Recurrent Unit (GRU), and Fully Convolutional Neural Networks (FCNN) were chosen for the models' selection and development. Due to their shown effectiveness in a range of image recognition tasks and possible flexibility to facemask detection, these models were selected. / Идентификация лицевых масок является важной задачей, которая влияет на здоровье и безопасность населения, особенно во время эпидемий инфекционных заболеваний. Многие архитектуры моделей глубокого обучения исследуются на предмет их эффективности, поскольку они продемонстрировали большой потенциал в автоматизации этого процесса. В этой работе проводится тщательное сравнение производительности четырех хорошо известных архитектур глубокого обучения —VGG19, VGG16, GRU и полностью сверточных нейронных сетей (FCNN)— для идентификации лицевых масок. Цель исследования - оценить эти архитектуры с точки зрения точности, эффективности и надежности, чтобы предоставить важную информацию для создания эффективных систем обнаружения лицевых масок. В этом исследовании рассматриваются преимущества и недостатки каждой модели в отношении распознавания лицевых масок путем тщательного тестирования и анализа. Модели подвергаются статистической оценке на предмет их способности обнаруживать лицевые маски на изображениях или в видеопотоках с использованием показателей производительности, включая точность, запоминаемость и показатель F1. Кроме того, фактическая возможность использования этих моделей в реальных приложениях оценивается путем анализа показателей вычислительной эффективности, таких как время вывода и размер модели. Более того, устойчивость моделей оценивается в ряде сложных сценариев, таких как изменение освещения, выражения лица и прикуса. В диссертации обсуждаются последствия этих результатов, а также предложения по улучшению каждой архитектуры для задач обнаружения лицевых масок. Методология этого исследования направлена на разработку и оценку моделей глубокого обучения для распознавания лицевых масок, которые особенно подходят для использования в мобильных медицинских учреждениях. Этот метод призван гарантировать высокую точность, надежность и эффективность в реальных условиях здравоохранения, где важно быстрое и точное распознавание лицевых масок. Для выбора и разработки моделей были выбраны четыре хорошо известные архитектуры глубокого обучения VGG19, VGG16, Gated Recurrent Unit (GRU) и полностью сверточные нейронные сети (FCNN). Эти модели были выбраны из-за их доказанной эффективности в решении целого ряда задач распознавания изображений и возможной гибкости в обнаружении лицевых масок. Ключевые слова: Распознавание лицевых масок, глубокое обучение, VGG19, VGG16, GRU, Полностью сверточные нейронные сети, Оценка эффективности, Мобильные медицинские учреждения.