tcpxtract

extracts files from network traffic based on file signatures
tcpxtract is a fast console tool to extract files from network traffic
based on file headers and footers (so called carving).
26 file formats are supported out of the box by tcpxtract but new formats
can be added without problems.
Foremost configurations are simple to convert to tcpxtracts configuration
files.
.
It uses libpcap and it can be used with tcpdump files.