is denoted d t the maximum total bitrate r t was taken to be about 50 kb s and the quantization parameter was taken to be 8 for compressing the video sequences for both video sequences q 0 u2159 results in a bitrate around 50 55 kb s at f 10 frames s hence the set of q 0 s used was q 0 u2159 u215b 1 20 note that the source bitrate decreases as qo decreases in the range q 0 u2159 to 1 20 q 0 u2159 corresponds t the case of maximum rate of transmission of i frames for each of the video sequences eight bitstreams were generated one for each value of q 0 frame lengths l 0 and l 1 used for the markov chain analysis were obtained by averaging the i frame and p frame lengths respectively of the compressed bitstreams and n i 3 was used based on the i frame size and mtu consideration for u201c akiyo u201d the following list summarizes the parameters used for the markov chain model fig3 a shows the resulting pr s 0 the probability of being in state s 0 fig3 b shows the average psnr for various values of q 0 and fig3 c shows the resulting fraction of reconstructed frames with distortion less than threshold d t to obtain fig3 b and 3 c the p frame retransmission rate q f1 derived from the markov chain analysis was manually tweaked so that the total bitrate source rate fec rate was very near to the source bitrate also the total bitrate for q 0 u2159 this was done to provide a fair comparison.