Structural Studies LMB

In color pattern recognition, color channels are normally processed separately and afterward the correlation outputs are combined. This is the definition of multichannel processing. We combine a single-channel method with nonlinear filtering based on nonlinear correlations. These nonlinear correlations yield better discrimination than common matched filtering. The method codes color information as amplitude and phase distributions and is followed by correlations related to binary decompositions. The technique is based on binary decompositions of the red, green, and blue and the hue, saturation, and intensity monochromatic channels of the reference and of the input scene, after which the binary information on the red, green, and blue channels and that of the hue, saturation, and intensity channels are encoded as different angles of a phase distribution. We have applied the method to images degraded by high levels of substitutive noise. Results show that the sliced orthogonal nonlinear generalized correlation detects the target with a high degree of discrimination when other methods fail.

Electrically addressed spatial light modulators (SLM) are widely used in optical image processors to display not only input images but also a huge variety of optical components such as lenses, complex filters and other diffractive elements. These components are fully programmable and dynamically controllable by computer thus bringing flexibility and new degrees of freedom to current optical and digital image processors. A good characterization is the most important step in the SLM initialization. The quality and effectiveness of the optical component addressed to the SLM strongly depends on the knowledge of the device response. This work deals with the spatial and temporal characterizations of reflective zerotwist liquid-crystal on silicon (LCoS) SLM. The signal is spatially modified before addressing it to the LCoS SLM to compensate for the distortions internally introduced by the device. For time varying optical components, the signal is also modified before addressing it to the LCoS SLM to compensate for the distortions internally introduced by the device when phase variations of 2π are required at high rate. Experimental results and applications in image processing are shown.

We introduce a single channel color nonlinear pattern recognition method. Usually, for color pattern recognition methods, the color are processed and finally its correlation outputs are combined. This is the definition of the common multichannel method. We take the input and reference scenes and we decompose them into their red, green and blue channels to obtain an amplitude and phase distribution. In this paper we study the correlations for highly noisy input iamges. These results are obtained by means of the sliced orthogonal nonlinear generalized correlation which detects the target with high discrimination capability in cases where other methods do not succeed.

We have developed a new data collection method and processing framework in full field cryo soft X-ray tomography to computationally extend the depth of field (DOF) of a Fresnel zone plate lens. Structural features of 3D-reconstructed eukaryotic cells that are affected by DOF artifacts in standard reconstruction are now recovered. This approach, based on focal series projections, is easily applicable with closed expressions to select specific data acquisition parameters.