In 3GPP a standard for multimedia streaming over mobile networks called PSS (packet-switched streaming service) has been specified. In order to deal with changing transmission characteristics like varying link bit-rate or handover, adaptive streaming features like client feedback have been included into Release 6 of 3GPP PSS. The adaptive behavior of the streaming server is not specified in PSS. In this paper, an adaptive video streaming system is presented that is compliant with PSS. Using PSS client feedback, transmission characteristics and client buffer status are determined. By means of transmission rate control, packet scheduling, video thinning, and bit-stream switching, the streaming server reacts to the determined transmission characteristics and the client buffer status. As video coding standard, H.264/AVC is used in the adaptive streaming system. Experimental results show that using the presented adaptive streaming system the overall video quality at the client is significantly improved in case of varying link bit-rate or handover.
['Thomas Schierl', 'Thomas Wiegand', 'Markus Kampmann']
3GPP compliant adaptive wireless video streaming using H.264/AVC