Sergio Carrato

Temporal video segmentation: A survey

Temporal video segmentation is the first step towards automatic annotation of digital video for browsing and retrieval. This article gives an overview of existing techniques for video segmentation that operate on both uncompressed and compressed video stream. The performance, relative merits and limitations of each of the approaches are comprehensively discussed and contrasted. The gradual development of the techniques and how the uncompressed domain methods were tailored and applied into compressed domain are considered. In addition to the algorithms for shot boundaries detection, the related topic of camera operation recognition is also reviewed.

A simple edge-sensitive image interpolation filter

A novel scheme for edge-preserving image interpolation is introduced, which is based on the use of a simple nonlinear filter which accurately reconstructs sharp edges. Simulation results show the superior performances of the proposed approach with respect to other interpolation techniques.

Design And Real-time Implementation Of A 3-D Rational Filter For Edge Preserving Smoothing

A nonlinear spatio-temporal filter capable of significantly attenuating noise in image sequences without corrupting image details is presented. The characteristics of the filter are described, and the results of several simulations on real-world sequences are shown. A real-time implementation of the algorithm on a last generation DSP is also described. It is shown that, by suitably exploiting the computational capability of the DSP, it is possible to process CIF images at 10 frames/sec.

An adaptive irregular sampling algorithm and its application to image coding

Abstract A novel irregular and nonuniform sampling scheme for image data is presented in this paper. Its main characteristics are the particular distribution of the samples along image edges and in textured areas, which is obtained following a multiresolution approach, and the low computational complexity. As an example of application, an image coding system is proposed which, thanks to both the peculiar sample distribution and a suitably designed interpolation scheme, yields good subjective quality images at low bit rates, avoiding the annoying artefacts which are typical of block-based coding techniques as JPEG.

A high quality 2 x image interpolator

In this paper, we present an innovative interpolator that performs high quality 2/spl times/interpolation on both synthetic and real world images. Its structure, which is based on a rational operator, provides edge-sensitive data interpolation so that sharp- and artifacts-free images are obtained at a reasonable computational cost.

An embedded control and acquisition system for multichannel detectors

Abstract We present a pulse counting multichannel data acquisition system, characterized by the high number of high speed acquisition channels, and by the modular, embedded system architecture. The former leads to very fast acquisitions and allows to obtain sequences of snapshots, for the study of time dependent phenomena. The latter, thanks to the integration of a CPU into the system, provides high computational capabilities, so that the interfacing with the user computer is very simple and user friendly. Moreover, the user computer is free from control and acquisition tasks. The system has been developed for one of the beamlines of the third generation synchrotron radiation sources ELETTRA, and because of the modular architecture can be useful in various other kinds of experiments, where parallel acquisition, high data rates, and user friendliness are required. First experimental results on a double pass hemispherical electron analyser provided with a 96 channel detector confirm the validity of the approach.

Video Enhancement and Dynamic Range Control of HDR Sequences for Automotive Applications

CMOS video cameras with high dynamic range (HDR) output are particularly suitable for driving assistance applications, where lighting conditions can strongly vary, going from direct sunlight to dark areas in tunnels. However, common visualization devices can only handle a low dynamic range, and thus a dynamic range reduction is needed. Many algorithms have been proposed in the literature to reduce the dynamic range of still pictures. Anyway, extending the available methods to video is not straightforward, due to the peculiar nature of video data. We propose an algorithm for both reducing the dynamic range of video sequences and enhancing its appearance, thus improving visual quality and reducing temporal artifacts. We also provide an optimized version of our algorithm for a viable hardware implementation on an FPGA. The feasibility of this implementation is demonstrated by means of a case study.

Asymmetrical twin cantilevers for single molecule detection

Recently, there has been growing interest in sensors based on frequency shift detection of mechanical resonators, that has led to extremely sensitive diagnostic methods for medicine and biology. Here the authors propose and demonstrate a strategy capable of detecting the presence of a few macromolecules, which uses an asymmetrical cantilever structure of several microns in size, operated at room temperature, and under ordinary vacuum conditions. The idea is to detect the presence of one or more molecules by detecting the mechanical cross-talk induced by the molecular link between a short cantilever and an array of longer cantilevers facing the short one.

Interpolation of the DC component of coded images using a rational filter

In this paper, the problem of the interpolation of the DC components of JPEG or MPEG-coded images is addressed, and the use of nonlinear interpolators is proposed which are able to accurately reconstruct the images yielding both sharp details and low blocking artifacts.

A deinterlacer for IQTV receivers and multimedia applications

A deinterlacer suitable for IQTV receivers and multimedia applications is presented. The processing is based on a hierarchical motion adaptive filtering. The proposed method effectively copes with the motion present in the scene: it performs a local interpolation using data lying along an estimated direction of motion. The algorithm is synthesized using VHDL (VHSIC Hardware Description Language) into FPGA (field-programmable gate array) components and in a single programmable ASIC (application-specific integrated circuit). >