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Depth range cameras are a promising solution for the 3DTV production chain. The generation of color images with their accompanying depth value simplifies the transmission bandwidth problem in 3DTV and yields a direct input for autostereoscopic displays. Recent developments in plenoptic video-cameras make it possible to introduce 3D cameras that operate similarly to traditional cameras. The use of plenoptic cameras for 3DTV has some benefits with respect to 3D capture systems based on dual stereo cameras since there is no need for geometric and color calibration or frame synchronization. This paper presents a method for simultaneously recovering depth and all-in-focus images from a plenoptic camera in near real time using graphics processing units (GPUs). Previous methods for 3D reconstruction using plenoptic images suffered from the drawback of low spatial resolution. A method that overcomes this deficiency is developed on parallel hardware to obtain near real-time 3D reconstruction with a final spatial resolution of800×600pixels. This resolution is suitable as an input to some autostereoscopic displays currently on the market and shows that real-time 3DTV based on plenoptic video-cameras is technologically feasible.

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A method is presented for determining the optical thickness, eVective droplet radius and temperature of oceanic stratocumulus clouds from NOAA-AVHRR infrared channels. The satellite data used in the present study correspond to night-time images in which large-scale stratiform clouds overlay the ocean. The procedure is based on the inversion of an atmospheric radiative transfer model that makes use of the discrete ordinates method called DISORT. A detailed study is presented which shows that cloud parameter retrieval is ambiguous, resulting in several possible solutions, because some pairs of eVective particle radius and optical thickness produce the same brightness temperatures. The discretization of these two parameters, based on the cloud layer radiative behaviour, is proposed to avoid these multiple solutions. In addition, the model inversion presents some diYculties that have been solved using a genetic algorithm. The current retrieval scheme is applied to satellite data to compare results with local in situ measurements and a good agreement is obtained in those pixels near the sample site.