We present a system for the transmission of high quality video streams such as MPEG-video streams in realtime over lossy channels. For protection against losses in the network during transmission we use a Forward Error Correcting (FEC) scheme called Erasure Resilient Transmission (ERT). ERT is an encoding scheme which provides multiple levels of redundancy in order to protect the different contents of a data set according to their importance. The task of assigning redundancies for the ERT encoding scheme is investigated for MPEG-1 encoded video sequences here. Furthermore we describe how to dynamically readjust the parameters of the ERT encoding scheme due to the changing sizes of the frames within a video sequence.