| Abstract |
We consider live unicast video streaming over
a packet erasure channel. To protect the transmitted data,
previous solutions use forward error correction (FEC),
where the channel code rate is fixed in advance according
to an estimation of the packet loss rate. However, these
solutions are inefficient under dynamic and unpredictable
channel conditions because of the mismatch between the
estimated packet loss rate and the actual one.We introduce a
new approach based on rateless codes and receiver feedback.
For every source block, the sender keeps on transmitting
the encoded symbols until it receives an acknowledgment
from the receiver indicating that the block was decoded
successfully. Within this framework, we provide an efficient
algorithm to minimize bandwidth usage while ensuring
successful decoding subject to an upper bound on the packet
loss rate. Experimental results showed that compared to
traditional fixed-rate FEC, our scheme provides significant
bandwidth savings for the same playback quality. |