[hpsdr] I/Q recording with "FLAC" compression

[Ken N9VV]

In 2004 I was introduced to the wonders of "FLAC" compression by 
Bob McGwier N4HY.

FLAC is located here: http://flac.sourceforge.net/

Bob introduced us all to this Open Source tool. FLAC is an 
excellent candidate for I/Q real-time recording and compression 
because it preserves the phase of the I/Q signals and is 
"Lossless" (unlike many other compression methods).

I recently created a 16MB .wav file with WinRad from I2PHD. The 
file plays back through WinRad with beautiful fidelity for all the 
signals that were captured during the recording session.

Then I used Audacity to import the .wav file and export it as a 
.FLAC file. The compression of FLAC changed the 16MB file to 2.5MB 
!!!  Audacity is Open Source and is located here:
http://audacity.sourceforge.net/

The FLAC file will not "play" with any SDR software, so I used 
Audacity again to re-convert the FLAC file back to .wav and then 
played it through WinRad to see that it retained the signal integrity.

I hope that the talented programmers in the OpenHPSDR group will 
consider the Open Source FLAC compression for I/Q recording in the 
future. While it may seem to be a bit rare and exotic, it 
certainly does a magnificent job of compression for these 
typically large I/Q files.  I see on the Perseus group that some 
of the MW SWL listeners are recording hours of very wide bandwidth 
selections that generate *Terabytes* of output .wav files. 
Perhaps OpenHPSDR can attract members of this active community 
with the alternative wonders of FLAC compression.

thank you for reading my email,
73 de Ken N9VV
-- 
if it's not CW it's CB