44 research outputs found
Efficient 1D and 2D barcode detection using mathematical morphology
Barcode technology is essential in automatic identification,
and is used in a wide range of real-time applications. Different
code types and applications impose special problems, so there is
a continuous need for solutions with improved performance.
Several methods exist for code localization, that are well
characterized by accuracy and speed. Particularly, high-speed
processing places need reliable automatic barcode localization,
e.g. conveyor belts and automated production, where missed
detections cause loss of profit. Our goal is to detect
automatically, rapidly and accurately the barcode location with
the help of extracted image features. We propose a new algorithm
variant, that outperforms in both accuracy and efficiency other
detectors found in the literature using similar ideas, and also
improves on the detection performance in detecting 2D codes
compared to our previous algorithm
Automatikus azonosĂtás Ă©s hitelesĂtĂ©s vizuális kĂłdokkal
Az automatikus azonosĂtás egyik legfontosabb Ă©s szĂ©les körben
alkalmazott eleme a vizuális kĂłdokkal törtĂ©nĹ‘ azonosĂtás. A
kĂĽlönbözĂ´ szimbĂłlumokkal Ă©s mintákkal megjelenĂtett
azonosĂtĂłk teszik lehetĂ´vĂ© a gĂ©pek számára az elektronikus
leolvasást, ami nagyban segĂti Ă©s gyorsĂtja a feldolgozást
pl. a bolti pénztáraknál, raktári átvételnél, nagy sebességű
feldolgozási helyeken, gyártósorokon. A szokásosan használt,
geometriai minták szerint tervezett kĂłdok általában tĂpusokat
vagy egyedeket azonosĂtanak. ElôállĂthatĂłk azonban olyan
mintázatok, melyek termĂ©szetĂĽknĂ©l fogva egyediek Ă©s Ăgy
eredetiség vagy hitelesség ellenôrzésére is alkalmazhatók.
Jelen Ărásunkban bemutatunk egy mĂłdszert QR kĂłdok gyors Ă©s
pontos detektálására mobil kĂ©szĂĽlĂ©kkel kĂ©szĂtett fĂ©nykĂ©peken,
valamint egy természetes mintázat felismerésére kidolgozott
eljárásunkat.
Alkalmazási területként bemutatunk egy olyan lehetséges
hibrid vizuális kód konstrukciót, melyben mesterséges és
természetes mintázatok együttes alkalmazásával elérhetô az
azonosĂtás Ă©s a hitelesĂtĂ©s is
Distance transform and template matching based methods for localization of barcodes and QR codes
Visual codes play an important role in automatic identification, which became an inseparable part of industrial processes. Thanks to the revolution of smartphones and telecommunication, it also becomes more and more popular in everyday life, containing embedded web addresses or other small informative texts. While barcode reading is straightforward in images having optimal parameters (fo cus, illumination, code orientation, and position), localization of code regions is still challenging in many scenarios. Every setup has its own characteristics, there fore many approaches are justifiable. Industrial applications are likely to have more fixed parameters like illumination, camera type and code size, and processing speed and accuracy are the most important requirements. In everyday use, like with smart phone cameras, a wide variety of code types, sizes, noise levels and blurring can be observed, but the processing speed is often not crucial, and the image acquisition process can be repeated in order for successful detection. In this paper, we address this problem with two novel methods for localization of 1D barcodes based on template matching and distance transformation, and a third method for QR codes. Our proposed approaches can simultaneously localize sev eral different types of codes. We compare the effectiveness of the proposed methods with several approaches from the literature using public databases and a large set of synthetic images as a benchmark. The evaluation shows that the proposed methods are efficient, having 84.3% Jaccard accuracy, superior to other approaches. One of the presented approaches is an improvement on our previous work. Our template matching based method is computationally more complex, however, it can be adapted to specific code types producing high accuracy. The other method uses distance transformation, which is fast and gives rough regions of interests that can contain valid visual code candidates
An approach to the quantitative assessment of retinal layer distortions and subretinal fluid in SD-OCT images
A modern tool for age-related macular degeneration (AMD) investigation is Optical Coherence Tomography (OCT), which can produce high resolution cross-sectional images of retinal layers. AMD is one of the most frequent reasons for blindness in economically developed countries. AMD means degeneration of the macula, which is responsible for central vision. Since AMD affects only this specific part of the retina, untreated patients lose their fine shape- and face recognition, reading ability, and central vision. Here, we deal with the automatic localization of subretinal fluid areas and also analyze retinal layers, since layer information can help to localize fluid regions. We present an algorithm that automatically delineates the two extremal retinal layers, successfully localizes subretinal fluid regions, and computes their extent. We present our results using a set of SD-OCT images. The quantitative information can also be visualized in an anatomical context for visual assessment
Synthesis of Novel Aromatic Core Zero Generation Dendrimers
Bromomethyl arenes used as polyfunctional core of dendrimers were derivatized with diethanolamine branches. The obtained compounds containing 4 or 6 hydroxyl terminal surface groups are highly water-soluble