Reduced decoder complexity and latency in pixel-domain Wyner-Ziv video coders

In some video coding applications, it is desirable to reduce the complexity of the video encoder at the expense of a more complex decoder. Wyner–Ziv (WZ) video coding is a new paradigm that aims to achieve this. To allocate a proper number of bits to each frame, most WZ video coding algorithms use a feedback channel, which allows the decoder to request additional bits when needed. However, due to these multiple bit requests, the complexity and the latency of WZ video decoders increase massively. To overcome these problems, in this paper we propose a rate allocation (RA) algorithm for pixel-domain WZ video coders. This algorithm estimates at the encoder the number of bits needed for the decoding of every frame while still keeping the encoder complexity low. Experimental results show that, by using our RA algorithm, the number of bit requests over the feedback channel—and hence, the decoder complexity and This work has been partially supported by the Spanish Ministry of Education and Science and the European Commission (FEDER) under grant TEC2005-07751-C02-01. A. Pižurica is a postdoctoral research fellow of FWO, Flanders. M. Morbee (B) · A. Pižurica · W. Philips TELIN-IPI-IBBT, Ghent University, Sint-Pietersnieuwstraat 41, Ghent 9000, Belgium e-mail: [email protected] A. Pižurica e-mail: [email protected] W. Philips e-mail: [email protected] A. Roca · J. Prades-Nebot GTS-ITEAM, Universidad Politécnica de Valencia, Camino de Vera s/n, 46022 Valencia, Spain e-mail: [email protected] J. Prades-Nebot e-mail: [email protected] the latency—are significantly reduced. Meanwhile, a very near-to-optimal rate-distortion performance is maintained.