I am currently working on the ability to change the
FEC rate and symbol rate without having to restart
the program.
The FEC rate code works well, when I select a new rate
the appropriate video bitrate is calculated and the
FFMPEG encoder is programmed with that rate also
the FEC mother code puncturing is adjusted to match.
It is interesting to see the change in quality as the
bitrate changes.
A change in symbol rate often causes a crash so some
further work is involved. I think I need to semaphore
protect the filter routines to stop this happening.
I have found an issue with the S/W MPEG encoding,
FFMPEG seems to have a minimum bitrate it will
operate at for a given picture size. For 70 cms it is
looking like I am going to have to change the number
of lines to get the lower bitrate I need. I have already
reduced the audio bitrate down to 64kbits from the
192kbits it was operating at originally.
Amateur TV used to be thriving in the Worthing
area but things are very quite now. Some people
have left the area, others got proper jobs in
broadcasting, others family commitments and
some have simply lost interest.
There are some newer Amateurs showing interest
in this facet of the hobby but I am not sure how to
engage them and to re-engage the lapsed souls.
I am not someone that particularly enjoys the social
side of the hobby, I prefer to stick to software
development. So I am not sure how to go about
the re-awakening, suggestions welcome!
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