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poc-fec

NAME

poc-fec - send FEC MP3 streams

SYNOPSIS

poc-fec [ -s address ] [ -p port ] [ -t ttl ] [ -q ] [ -k fec_k ] [ -n fec_n ] files...

DESCRIPTION

poc-fec is a streaming server sending mp3 data using a custom FEC protocol. The streamed MP3 frames are first decomposed in autonomous data units (ADUs). These ADUs are grouped into ADU groups, which are encoded redundantly using a FEC method by Luigi Rizzo. A group of k ADUs is encoded as n data packets. Any k of these n data packets is sufficient to recover the original k ADUs. It sends the files in the order given on the command-line. Use the filename - to stream from standard input. Normally, the FEC protocol is used to stream to multicast groups.

OPTIONS

-s address

Specify the address to send to (default 224.0.1.23).

-p port

Specify the port to send to (default 1500).

-t ttl

Specify the TTL parameter to be set on outgoing parameters (default 1).

-q

Don't output any information on standard error.

-k fec_k

Specify the number of ADUs that will be encoded as an ADU group (default 20).

-n fec_n

Specify the number of packets that the ADU groups will be encoded to (default 25). This number must be greater than the fec_k parameter.

EXAMPLES

poc-fec -s 224.0.1.24 -p 8989 -t 2 -k 16 -n 32 bla.mp3

Send the file bla.mp3 using the RTP RFC fec protocol to the address 224.0.1.24 on port 8989, and set the TTL to 2. MP3 frames of bla.mp3 are converted to ADUs and grouped in ADU groups of 16 ADUs. These 16 ADUs are encoded into 32 packets and streamed. A client will have to receive at least 16 packets to recover the original ADUs.

AUTHORS

Manuel Odendahl <manuel@bl0rg.net>, Florian Wesch <dividuum@bl0rg.net>