[Nottingham] [Talk] *TODAY* 8:30pm Thursday 27/08/2020: How best to develop something new?

Martin martin at ml1.co.uk
Thu Aug 27 19:56:51 UTC 2020


> *TODAY* 8:30pm (BST) Thursday 27/08/2020 (That's 7:30pm _GMT_  )
> https://meet.jit.si/NLUGmeet11

> *How best to develop something new* ?
> =====================================

For just one small but powerful example of the "*nix" way of doing things:

>> Unix "Do one thing and do it well"
>> https://principles.design/examples/unix-philosophy
>> http://www.catb.org/esr/writings/taoup/html/ch01s06.html
>> https://en.wikipedia.org/wiki/Unix_philosophy

>> Elon Musk and SpaceX vs NASA and Big Corporates(!)
>> https://en.wikipedia.org/wiki/Elon_Musk#SpaceX

We have a double example for just one of many ways to view, live, the
very rapid developments of SpaceX at Boca Chica, Texas. Live.


(By the power of Google YouTube)


And choosing one of the live streams:

(For example)

Sapphire Cam SpaceX Boca Chica Launch Facility

(Note: The livestream address changes every 8 hours or so.)

And your web browser should display a livestream of:

Sapphire Cam SpaceX Boca Chica Launch Facility

That webcam is a telephoto camera that is mounted at 350 ft in altitude
on top of the Sapphire Condominiums and is 5.9 miles from the Space X

Going the *nix way for viewing, there is the one-liner:

youtube-dl -o - 'https://www.youtube.com/watch?v=CQJInT3-_-s' | ffplay
-fs -an -

Where "youtube-dl" grabs a video stream and "ffplay" displays a video

The ffplay "-fs" specifies use full screen, and "-an" specifies no audio.

The "|" is the magical 'pipe' operator that connects to the processes

Now comes the clever bits...

"youtube-dl" accommodates streaming or downloading for a phenomenal list
of sites and formats.

See: https://ytdl-org.github.io/youtube-dl/supportedsites.html

And ffplay can do some clever processing trickery...

The Sapphire Cam is high and distant... So there is a lot of image
wobble due to atmospherics and the tower blowing in the wind.

(Lots of wobble as hurricane Laura blasts past...)

Hence, with the magic of a little real-time image processing...

To average out the thermals:

youtube-dl -o - 'https://www.youtube.com/watch?v=CQJInT3-_-s' | ffplay
-fs -an -vf tmix=frames=4:weights='1 1 1 1'  -

And to additionally average out the windy wobbles:

youtube-dl -o - 'https://www.youtube.com/watch?v=CQJInT3-_-s' | ffplay
-fs -an -vf tmix=frames=8:weights='1 1 1 1 1 1 1 1'  -

Fantastic stuff!

Would that work as well following?:

>> And if time permits such that we are on the right side of midnight:
>> Poettering:
>> 'Speeding up Linux development at the expense of breaking compatibility'
>> https://en.wikipedia.org/wiki/Lennart_Poettering#Controversies
>> https://en.wikipedia.org/wiki/PulseAudio#Adoption
>> https://en.wikipedia.org/wiki/Systemd#Adoption


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