Don't forget that we had perfectly functional SSTV software 10 years ago with JVFAX, which didn't even use a sound card. Just a 1-bit interface - an opamp tied to the control lines of a serial port on an 8 mHz 286 PC running MS-DOS. Scottie-1 on 20 meters, yeah! It didn't decode Robot-36, but I figured out that I could receive the SSTV pictures from MIR by using one of the B&W modes.
Greg KO6TH
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From: [email protected] To: [email protected]; [email protected] Date: Fri, 17 Oct 2008 15:20:33 +0200 Subject: [amsat-bb] Re: SSTV Algorithms?
Hi,
Briefly - the SSTV developers have their own algorithms more-or-less, what we are mostly interested in is the frequency at a point in time. Simplifying things further - we need to know frequency for each point in the line, the filtering we use to pre-process the incoming signal removes noise etc. After all - it's an analogue specification.
There would be no advantage to sampling at 48kHz instead of 8kHz, in fact it would use a lot more CPU to run the filters.
The filtering we use is very standard stuff, SSTV is a nice and simple concept, the big problem is combating noise, fading and multi-path interference.
Simon Brown, HB9DRV www.ham-radio-deluxe.com
----- Original Message ----- From: "Curt Nixon"
I wasn't so interested in the actual SSTV algorithms as I was in seeing if there is any visible difference in the result of different algorithm use--or is everyone using the same decoding kernel?
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