Minutiae Extraction and Filtering from Gray-Scale Images

Visual cryptography (VC) has found numerous applications in privacy protection, online transaction security, and voting security, etc. To counteract potential cheating attacks, Lin et al. proposed flip visual cryptography in 2010, where a second secret image can be revealed by stacking one share with a flipped version of another share. The second secret image can be designed as an additional verification mechanism. However, Lin’s scheme produces meaningless shares and is only applicable to binary secret images. It is interesting to explore whether it is possible to extend the flip VC to having cover images (i.e., extended VC) and these cover images are color images. This problem is challenging since too many restricting conditions need to be met. In this paper, we designed a flip VC for gray-scale and color cover images based on constraint error diffusion. We show that it is possible to meet all the constraints simultaneously. Compared with existing schemes, our scheme enjoys the following features: Color cover images, no computation needed for decoding, and no interference from cover image on the recovered secret image.

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Gray Scale Image Coloring Method Based on GAN

Proceedings of the 3rd International Conference on Data Science and Information Technology ◽

10.1145/3414274.3414485 ◽

2020 ◽

Author(s):

Long Guo ◽

Lu Liang ◽

Shi Zeng ◽

Ji He ◽

Gaoshang Dai

Keyword(s):

Gray Scale ◽

Gray Scale Image

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Optical response of helix-free FLC: Continuous gray scale, fastest response, and lowest control voltage

Journal of the Society for Information Display ◽

10.1002/jsid.226 ◽

2014 ◽

Vol 22 (2) ◽

pp. 115-121 ◽

Cited By ~ 8

Author(s):

Alexander L. Andreev ◽

Tatiana B. Andreeva ◽

Igor N. Kompanets ◽

Nikolay V. Zalyapin

Keyword(s):

Optical Response ◽

Control Voltage ◽

Gray Scale

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A technical note on intra-arterial cone-beam computed tomography for the evaluation of flow-diverter stents: Image quality differences between diluted and non-diluted contrast medium

Interventional Neuroradiology ◽

10.1177/1591019919890929 ◽

2019 ◽

Vol 26 (2) ◽

pp. 164-169

Author(s):

Naci Kocer ◽

Sedat G Kandemirli ◽

Daniel Ruijters ◽

Michalis Mantatzis ◽

Osman Kizilkilic ◽

...

Keyword(s):

Computed Tomography ◽

Image Quality ◽

Contrast Medium ◽

Cone Beam Computed Tomography ◽

Vessel Wall ◽

Flow Diverter ◽

Cone Beam ◽

Gray Scale ◽

Stent Deployment ◽

Contrast Technique

Background Design of flow-diverter stents for flexibility, tractability, and low profile limits their radiopacity on conventional digital subtraction angiography. Cone-beam computed tomography (CBCT) offers higher spatial resolution for the evaluation of flow-diverter stents. However, CBCT requires optimal dilution and timing of contrast medium for simultaneous visualization of the stent, arterial lumen, and vessel wall. There are only limited data on the effects of different contrast dilutions on CBCT image quality in neurointerventional applications. Materials and methods In our institution, intra-arterial CBCTs were acquired during stent deployment and at follow-ups with 10% diluted contrast. We had recently started acquiring intra-arterial CBCTs with non-diluted contrast. Retrospective analysis of our flow-diverter data identified eight cases with different aneurysm locations who had intra-arterial CBCT with 10% diluted contrast immediately after flow-diverter stent deployment and with non-diluted contrast technique during follow-ups. For each case, the image quality between diluted and non-diluted contrast techniques was compared qualitatively by assessing stent visualization and quantitatively by plotting gray-scale intensity values along the vessel lumen. Results In two sets of CBCT images per each case, there was no substantial difference between diluted and non-diluted CBTC techniques for the evaluation of stent architecture and lumen opacification. Gray-scale intensity values perpendicular to the lumen revealed similar intensity values along the neighboring parenchyma, vessel wall, and lumen for the two different contrast techniques. Conclusion Intra-arterial CBCT angiography can be performed without contrast dilution and still achieve adequate image quality in certain cerebral aneurysms treated with flow diverter. The non-diluted contrast technique avoids the time loss during preparation of diluted contrast and installation of diluted contrast to the injector in angiography suites with a single power injector.

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