1,749 research outputs found
An automatic image analysis methodology for the measurement of droplet size distributions in liquid–liquid dispersion: round object detection
This article presents an efficient and economical automatic image analysis technique for the droplet characterization in a liquid–liquid dispersion. The methodology employs a combination of the Satoshi Suzuki's [Topological structural analysis of digitized binary images by border following. Comput Vis Graph Image Process. 1985;30:32–46] find contours algorithm and the method of minimal enclosing circle identification, proposed by Emo Welzl [Smallest enclosing disks (balls and ellipsoids). Berlin, Heidelberg: Springer; 1991. p. 359–370. chapter 24], to achieve the objectives. The round object detection algorithm has been designed for the identification and verification of correct droplets in the mixture which helped to increase the accuracy of automatic detection. Tests have been performed on various sets of images obtained during several emulsification processes and contain examples of droplets which differ in size, density, volume and appearance etc. An effective communication between the two methodologies and newly introduced algorithms demonstrated an accuracy of 90% or above in the measurement of droplet size distribution and Sauter mean diameters through an automatic vision-based system
Anveshak - A Groundtruth Generation Tool for Foreground Regions of Document Images
We propose a graphical user interface based groundtruth generation tool in
this paper. Here, annotation of an input document image is done based on the
foreground pixels. Foreground pixels are grouped together with user interaction
to form labeling units. These units are then labeled by the user with the user
defined labels. The output produced by the tool is an image with an XML file
containing its metadata information. This annotated data can be further used in
different applications of document image analysis.Comment: Accepted in DAR 201
Artificial Image Tampering Distorts Spatial Distribution of Texture Landmarks and Quality Characteristics
Advances in AI based computer vision has led to a significant growth in
synthetic image generation and artificial image tampering with serious
implications for unethical exploitations that undermine person identification
and could make render AI predictions less explainable.Morphing, Deepfake and
other artificial generation of face photographs undermine the reliability of
face biometrics authentication using different electronic ID documents.Morphed
face photographs on e-passports can fool automated border control systems and
human guards.This paper extends our previous work on using the persistent
homology (PH) of texture landmarks to detect morphing attacks.We demonstrate
that artificial image tampering distorts the spatial distribution of texture
landmarks (i.e. their PH) as well as that of a set of image quality
characteristics.We shall demonstrate that the tamper caused distortion of these
two slim feature vectors provide significant potentials for building
explainable (Handcrafted) tamper detectors with low error rates and suitable
for implementation on constrained devices.Comment: 6 pages, 7 figures, 3 table
О распознавании форменных объектов крови на основе медицинских изображений
Рассматривается задача постановки возможного диагноза по гематологическому анализу цифрового изображения эритроцитов. Описываются шаги по предварительной обработке изображения для уменьшения шумов и точности сегментации объектов клеток на классы. Для каждого этапа приведены примеры работы фильтро
Unconventional TV Detection using Mobile Devices
Recent studies show that the TV viewing experience is changing giving the
rise of trends like "multi-screen viewing" and "connected viewers". These
trends describe TV viewers that use mobile devices (e.g. tablets and smart
phones) while watching TV. In this paper, we exploit the context information
available from the ubiquitous mobile devices to detect the presence of TVs and
track the media being viewed. Our approach leverages the array of sensors
available in modern mobile devices, e.g. cameras and microphones, to detect the
location of TV sets, their state (ON or OFF), and the channels they are
currently tuned to. We present the feasibility of the proposed sensing
technique using our implementation on Android phones with different realistic
scenarios. Our results show that in a controlled environment a detection
accuracy of 0.978 F-measure could be achieved.Comment: 4 pages, 14 figure
WordFences: Text localization and recognition
En col·laboració amb la Universitat de Barcelona (UB) i la Universitat Rovira i Virgili (URV)In recent years, text recognition has achieved remarkable success in recognizing scanned
document text. However, word recognition in natural images is still an open problem,
which generally requires time consuming post-processing steps. We present a novel architecture
for individual word detection in scene images based on semantic segmentation.
Our contributions are twofold: the concept of WordFence, which detects border areas
surrounding each individual word and a unique pixelwise weighted softmax loss function
which penalizes background and emphasizes small text regions. WordFence ensures that
each word is detected individually, and the new loss function provides a strong training
signal to both text and word border localization. The proposed technique avoids intensive
post-processing by combining semantic word segmentation with a voting scheme
for merging segmentations of multiple scales, producing an end-to-end word detection
system. We achieve superior localization recall on common benchmark datasets - 92%
recall on ICDAR11 and ICDAR13 and 63% recall on SVT. Furthermore, end-to-end
word recognition achieves state-of-the-art 86% F-Score on ICDAR13
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