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We attempt to model and visualize the main characteristics of cracks produced on the surface of a desiccating crusted soil: their patterns, their different widths and depths and their dynamics of creation and evolution. In this purpose we propose a method to dynamically produce three-dimensional (3D) quasi-static fractures, which takes into account the characteristics of the soil. The main originality of this method is the use of a 3D discrete propagation of 'shrinkage volumes' with respect to 2D precalculated paths. In order to get realistic cracks, we newly propose to take into account a possibly inhomogeneous thickness of the shrinking layer by using a watershed transformation to compute these paths. Moreover, we use the waterfall algorithm in order to introduce in our simulation a hierarchy notion in the cracks appearance, which is therefore linked with the initial structure of the surface. In this paper, this method is presented in detail and a validation of the cracks patterns by a comparison with real ones is given.

We propose a new methodology to acquire HDR video content for autostereoscopic displays by adapting and augmenting an eight view video camera with standard sensors. To augment the intensity capacity of the sensors, we combine images taken at different exposures. Since the exposure has to be the same for all objectives of our camera, we fix the exposure variation by applying neutral density filters on each objective. Such an approach has two advantages: several exposures are known for each video frame and we do not need to worry about synchronization. For each pixel of each view, an HDR value is computed by a weighted average function applied to the values of matching pixels from all views. The building of the pixel match list is simplified by the property of our camera which has eight aligned, equally distributed objectives. At each frame, this results in an individual HDR image for each view while only one exposition per view was taken. The final eight HDR images are tone-mapped and interleaved for autostereoscopic display.

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