Snifter is a raw socket IP packet capturing tool for Windows, with a tiny CPU and memory footprint.
Output is written in PCAPNG format, and you can filter captured packets based on protocol, source/destination address and source/destination port
You can't capture on the local loopback address 127.0.0.1 with a Windows packet capture driver like WinPcap - but you can by using a raw socket sniffer like Snifter.
You must run Snifter with elevated privileges - this is a Windows requirement to create raw sockets.
For now at least, Snifter only supports IPv4. It should be straightforward to add support for IPv6, but I don't use IPv6 yet, so haven't added it.
snifter.exe -i x -f filename
-i, --interface=VALUE ID of the interface to listen on
-f, --filename=VALUE Filename to output sniffed packets to. Defaults to snifter.pcapng
-o, --operator=VALUE Whether filters should be AND or OR. Defaults to OR
-p, --protocol=VALUE Filter packets by IANA registered protocol number
-s, --source-address=VALUE Filter packets by source IP address
-d, --dest-address=VALUE Filter packets by destination IP address
-x, --source-port=VALUE Filter packets by source port number
-y, --dest-port=VALUE Filter packets by destination port number
-h, -?, --help Show command line options
Run snifter.exe -h to see a list of available network interfaces.
Note that each filter option can only be specified once.