*Shredpix* converts images to COFDMTV encoded audio signals and is based on open-source software.

COFDMTV is based on COFDM (coded orthogonal frequency-division multiplexing) technology:
- 160 ms long OFDM symbols
- 6.25 Hz per sub-carrier
- 1/8 guard interval
- differentially encoded PSK (phase-shift keying) modulation
- systematic polar codes for forward error correction

Following modes are supported:

Using SPC(64800, 43072):
Mode 6: 8PSK, 2700 Hz BW and about 10 seconds long
Mode 7: 8PSK,