[amsat-bb] Re: SSTV Algorithms?

[Greg D.]

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


----------------------------------------
> From: simon at hb9drv.ch
> To: cptcurt at flash.net; amsat-bb at amsat.org
> 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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