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Smartphones with an in-built camera are omnipresent today in the life of over eighty percent of the world's population. They are very often used to photograph documents. Document binarization is a key process in many document processing platforms. This paper assesses the quality, file size and time performance of sixty-eight binarization algorithms using five different versions of the input images. The evaluation dataset is composed of deskjet, laser and offset printed documents, photographed using six widely-used mobile devices with the strobe flash off and on, under two different angles and four shots with small variations in the position. Besides that, this paper also pinpoints the algorithms per device that may provide the best visual quality-time, document transcription accuracy-time, and size-time trade-offs. Furthermore, an indication is also given on the "overall winner" that would be the algorithm of choice if one has to use one algorithm for a smartphone-embedded application. [ABSTRACT FROM AUTHOR]

Professional long drivers can hit golf balls to a speed of up to 350 km/h. Extremely short exposure time is required to capture the objects moving that fast without blur. The very high frame rate is also required to capture the sufficient sequence of object movements within the field of view in order to predict trajectory, which means a sacrifice in frame image resolution at fixed data throughput. This paper presents a high-speed stereo vision system that is able to track the golf ball motion at the speed of up to 360 km/h under normal indoor lighting conditions. Binocular camera operated at 810 frames/s with 35- $\mu \text{s}$ exposure time, requiring no additional strobe lights in order not to compromise user experiences. Ball markers were designed for spin measurement. To detect balls and identify markers from highly underexposed low resolution images, new algorithms were developed and implemented on field-programmable gate array board with an advanced RISC machines CPU. The experimental results showed high detection rate and high accuracy with overall processing time less than 300 ms. [ABSTRACT FROM AUTHOR]

Abstract: We report on the development of a vibrometer for in-plane motion which is particularly suitable for Micro Electro Mechanical System (MEMS) samples. The system combines a conventional microscope, coherent electronics and a Full Frame CCD camera. Stroboscope lighting allows the system to freeze the motion. The obtained images correspond to different phases of the sample motion. Different subpixel motion measurement algorithms are compared in terms of precision and computation time. An algorithm that we specially design for this application proved to be the best. It is based on the shift Fourier theorem and uses first harmonics, where most energy is present. Thus the system allows computing the phase and magnitude of the sample displacement. With the system we can obtain a measurement resolution of 100pm demonstrated on the AFM cantilever vibrations measurement. The effect of the edge roughness was studied. It decreases the performance of the algorithm but roughness is very low on most MEMS applications. This method based on a CCD camera, is very well suited for measuring in-plane MEMS vibration since it does not require surface roughness for scattering the light as with the speckle methods (for example). It can quickly obtain full field motion, with a high precision. Furthermore, the used algorithm is simple, fast and very noise insensitive. [Copyright &y& Elsevier]

Two-colour image correlation velocimetry is applied to distinct smoke-wire streaklines in turbulent pipe flow. A single frame from a 35-mm film camera is exposed to two consecutive flashes, one from a red and one from a blue stroboscope. The resulting composite image is digitized, and the color components are extracted to obtain two images. Image correlation is then applied to estimate the velocity which is then compared with hot-wire velocity measurements. [ABSTRACT FROM AUTHOR]

The article focuses on the moving pictures of how individual transcription factors find, bind and regulate their target genes developed by researchers Johan Elf, Gene-Wei Li and Sunney Xie. The research team expressed a fluorescent lac repressor fusion protein to follow directly the kinetics of individual lac repressors. They were able to capture individual repressor molecules as they move around the cell through the use of a sensitive camera and a high-intensity stroboscopic laser.