SSDV encoding, decoding, RTTY

I was able to packetize a jpeg file, send it using RTTY encoded audio, and decode using dl-fldigi to reconstruct the picture –  with a 33% error rate.


Encode jpeg file (note: file should be fairly small with dimensions that are multiples of 16) Using fsphil’s SSDV software:

./ssdv -e -c KA1IS -i 1 24.jpeg test1.pkt


./ssdv -d  test1.pkt test3.jpeg


Currently using multimode to encode and dl-fldigi to decode. dl-fldigi is the only software that internally supports the SSDV packets.

To get any results, RTTY must be at ascii, 8 bits, no parity, 2 stop bits. The other settings I will need to tweak for maximum throughput, but with this simple setup the error rate was way too high. Especially considering there was no radio involved.

Any way it sort of works