A computer vision system tries to mimic our primary sense (sight) in order to gather information without the need for physical interaction, in fact such systems are able to grade automatically, and extract useful information with a degree of sensitivity closer to that of a human, reducing considerably the margin of error. By performing digital image processing, defined as the acquisition and processing of visual information by computer, computer vision systems allow analyzing image data for specific applications in order to determine how images can be used to extract the required information. Among the most important features for accurate classification and sorting of products it can be mentioned the shape. The shape of objects or regions of interest are important features used for content representation, and require good segmentation to detect objects or regions. Basically, shape characterization is of two types: boundary-based and regionbased. Boundary-based shape features include rectilinear shapes, polygonal approximation, finite element models, and Fourier-based shape descriptors. Region-based features include statistical moments and grid-based approaches. Object shape detection using a technique based on Hough Transform for further segmentation is presented on this paper

We have probed the luminescence properties of a wide-band-gap, direct band-gap optoelectronic material, grown on closely lattice-matched silicon substrates, namely, $\gamma \text{-}\mathrm{Cu}\mathrm{Cl}$ on Si. This material system is compatible with current Si or GaAs-based electronic/optoelectronic technologies. Polycrystalline epitaxy of CuCl can be controlled such that it maintains an orientation similar to the underlying Si substrate. Importantly, chemical interactions between CuCl and Si are eliminated. Photoluminescence and cathodoluminescence results for CuCl, deposited on either Si (100) or Si (111), reveal a strong room-temperature $Z_3$ excitonic emission at $\sim 387\mathrm{nm}$ . We have developed and demonstrated the room-temperature operation of an ultraviolet electroluminescent device fabricated by the growth of $\gamma \text{-}\mathrm{Cu}\mathrm{Cl}$ on Si. The application of an electrical potential difference across the device results in an electric field, which promotes light emission through hot-electron impact excitation of electron-hole pairs in the $\gamma \text{-}\mathrm{Cu}\mathrm{Cl}$ . Since the excitonic binding energy in this direct band-gap material is of the order of $190\mathrm{meV}$ at room temperature, the electron-hole recombination and subsequent light emission at $\sim 380$ and $\sim 387\mathrm{nm}$ are mediated by excitonic effects.

BACKGROUND: Anthocyanins are the main compounds responsible for the colour of red wines and therefore it may be important to evaluate the content of the aforesaid secondary metabolites during grape ripening due to the crucial importance to determine wine colour. Nowadays, there is a growing demand of rapid and non‐destructive analytical tools for analysing grapes, such as the emerging hyperspectral analysis.RESULTS: The hyperspectral images of intact grapes (Vitis vinifera L. cv. Tempranillo, Graciano, Garnacha and Mazuelo red grape from vineyards located in the D.O.Ca. Rioja at two different developmental stages) were recorded using a near infrared hyperspectral imaging device (900–1700 nm). Reference values of anthocyanins were obtained by HPLC‐DAD. Calibrations were performed by modified partial least squares regression and present a good potential (coefficient of determination of 0.72 and standard error of cross‐validation values of 0.78 and 0.70 mg per grape for total and non‐acylated anthocyanins respectively).CONCLUSION: The procedure reported here presents a good potential for a fast and reasonably inexpensive screening of these compounds in intact single berries. Moreover, the heterogeneity of anthocyanins within the same ripeness stage could be evaluated using this non‐detructive tool. © 2015 Society of Chemical Industry