patmosxx-v2 / reed-solomon Goto Github PK

Make sure you have libfec-dev or equivalent installed. If your OS does not have this as package, check out out KA9Q's site

Also make sure you have cmake.

Then:

mkdir build; cd build 
cmake ..
make

Then try:

./rscmd --help

This command will allow you to encode and decode messages using all Reed-Solomon configurations, as long as the symbol size is 8 bits.

A sample run:

$ ./rscmd "bert hubert"
nroots: 32
prim: 11
fcr: 121
poly: 1 + x + x^2 + x^7 + x^8
polyval: 0x187
(N,K) = (255,223)
The 32 parity bytes for "bert hubert": ddaa8fd46499675b712186a0da1dd8738bee3df7f25b49c2c0e84e4a8fe8137b

This runs the command with the most bog standard Reed-Solomon settings, and creates 32 parity bytes for the string "bert hubert".

To test if it worked, let us corrupt this string a bit (or arguably fix it):

$ ./rscmd "nerd hubert" ddaa8fd46499675b712186a0da1dd8738bee3df7f25b49c2c0e84e4a8fe8137b
nroots: 32
prim: 11
fcr: 121
poly: 1 + x + x^2 + x^7 + x^8
polyval: 0x187
(N,K) = (255,223)
Fixed 2 corruptions in positions: 0 3
Recovered: bert hubert

If you are unsure about your chosen parameters, try --exercise somestring. This will do 10000 encode/decode cycles, where each time the message is mangled as much as possible while staying within what should be recoverable.