Marco Modena

A new data structure for variable bit rate broadcast video transmission on ATM network

The asynchronous transfer mode (ATM) technique will probably increase the demand for sophisticated video services. The availability of wide bandwidth and fast rerouting at affordable rates will influence the design of new video codecs. Firstly, variable bit rate coding algorithms can efficiently be employed in order to achieve a uniform picture quality at the receiver. Secondly, the impairment due to cell loss that may occur in the ATM environment demands specialized error concealment strategy. In this paper the segmentation and reassembling of the bit stream generated by a hybrid DCT broadcast quality video codec is addressed. A VIDEO PACKET (V.P.), composed of a variable number of ATM cells, is associated to a defined portion of the television signal. Predefined patterns and layered protection included in the V.P. allow the detection of lost cells and consequently the application of a simple error concealment technique.