Distributed video coding (DVC) is a new video coding paradigm based on two key Information Theory results: the Slepian-Wolf and Wyner-Ziv theorems. A particular case of DVC, the so-called Wyner-Ziv coding, deals with lossy source coding with side information at the decoder and enables a flexible allocation of complexity between the encoder and the decoder. This paper proposes an improved transform domain Wyner-Ziv video codec including: 1) the integer block-based transform defined in the H.264/MPEG-4 AVC standard, 2) a quantizer with a symmetrical interval around zero for AC coefficients, and a quantization step size adjusted to the transform coefficient bands dynamic range, and finally and 3) advanced frame interpolation for side information generation. The combination of these tools brings significant rate-distortion (RD) gains regarding the state-of-the-art results available in the literature.

Recently, the JPEG standardization committee created an initiative called JPEG Pleno. "Pleno" is a reference to "plenoptic," a mathematical representation that not only provides information about any point within a scene but also about how it changes when observed from different positions. "Pleno" is also the Latin word for "complete," a reference to the JPEG committee's desire for future imaging to provide a more complete description of scenes, well beyond what's possible today. Here, we discuss the rationale behind the vision for the JPEG Pleno initiative and describe how it can potentially reinvent the future of imaging.

In this paper, an original spatial shape error-concealment technique, to be used in the context of object-based image and video coding schemes, is proposed. In this technique, it is assumed that the shape of the corrupted object at hand is in the form of a binary alpha plane, in which some of the shape data is missing due to channel errors. From this alpha plane, a contour corresponding to the border of the object can be extracted. However, due to errors, some parts of the contour will be missing and, therefore, the contour will be broken. The proposed technique relies on the interpolation of the missing contours with Bézier curves, which is done based on the available surrounding contours. After all the missing parts of the contour have been interpolated, the concealed alpha plane can be easily reconstructed from the fully recovered contour and used instead of the erroneous one improving the final subjective impact.

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