Generation of redundant frame structure for interactive multiview streaming
While multiview video coding focuses on the rate-distortion performance of compressing all frames of all views, we address the problem of designing a frame structure to enable interactive multiview streaming, where clients can interactively switch views during video playback. Thus, as a client is playing back successive frames (in time) for a given view, it can send a request to the server to switch to a different view while continuing uninterrupted temporal playback. Noting that standard tools for random access (i.e., I-frame insertion) can be inefficient for this application, we propose a technique where redundant representations of some frames can be stored to facilitate view switching. We first present an optimal algorithm with exponential running time that generates such a frame structure so that the expected transmission rate is optimally traded off with total storage. We then present methods to reduce the algorithm complexity for practical use. We show in our experiments that we can generate redundant frame structures offering a range of tradeoff points with transmission and storage, including ones that outperformsimple I-frame insertion structures by up to 48%in terms of bandwidth efficiency for similar storage costs.