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Mark Atwood
I recently wrote an offhand post about doing software archaeology at my job into the FFmpeg project, and one of my nephews, who is very smart but his passions go doing a different path than mine responded with: "I have no idea what you're talking about but I'm sure it's great", and thus so, I wrote up a slightly longer lecture/essay as a comment reply. Then my friend Tim Lord responded with: "that description of codecs deserves to be someplace besides only in a comment on a Facebook post -- cogent, unpatronizing, good refresher". And thus so, here it is:



A codec is a software that turns sound or video into a computer file or back again. Every phone call you have ever heard, and every movie you have ever seen, and all the recorded music you have ever heard (except for actual film movies or phonographs or old cassette tapes) has been processed by an enCODer to record it, and another DECoder to play it back to you.



There are many many many different codecs. Early ones were designed around the limits that computers were not very fast or very powerful, so they did not do a very good job of using the fewest number of computer bits for the best possible audio or video. We have codecs today that are very very good at it, because our computers are fast and powerful enough.

There are many old codecs we can't easily stop using because they are built into systems that can't be easily all replaced at once, such as satellite receivers, telephone switches, and handset cellphones.

Some codecs were created to play movies and sound for computer games, and so the codec software was built into that particular game, and used only for one or a few games, and then never used again.

Codecs are very difficult to design well, because they depend on how human brains, human eyes, and human ears work. To save space, a codec does not want to spend computer power saving or playing back the parts of music or video that your brain cannot hear or see. So codec designers have to study human perception, and have to test things out on human volunteers, which is slow and expensive.

Widely used codecs are often "standards". Corporations, governments, and universities will work together to carefully design a codec that then can be used in many places at once, so that lots of systems can all talk to each other.

One of those groups is called the "Motion Picture Experts Group", which is supervised by an organization called the "International Standards Organization", and one of the standard codecs they designed was called "Audio Layer", and they made several versions of Audio Layer until the 3rd version was good enough. Thus "ISO MPEG version 2 AL version 3", or for short "MP3".

FFmpeg is an open source software project that was originally an implementation of one of the MPEG video codecs, but since then has become a project that tries to have an implementation of every possible codec. FFmpeg contains old codecs that are no longer used, old codecs that are still widely used, codecs that were used in old video games and never used again, new codecs that are now used a lot, and also lots of experimental codecs that people wrote to figure out what does and does not work in a codec.

Because FFmpeg has so many codecs in it, people now use it to "translate anything to anything", and they also use it to analyze and process audio and video information. My own employer uses FFmpeg in many places inside our company, to do lots of the things that our customers pay us for.



My nephew then had the question "So JPEG artifacts are because of an outdated codec?", to which I responded:

Every codec has artifacts if driven too hard, if its told "no, compress it even harder, fewer bits". There are newer codecs that are better than JPEG that don't start having visible artifacts so soon, and have artifacts that are less distracting. But we can't change all the image viewing software everywhere, so we will have to live with JPEG for a long time.

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When I was living in Alaska in 1989, I bought a used Minolta Maxxum 35mm film camera. It had integrated autofocus, which was cutting edge at the time. And it came with a couple of 3rd party lenses, so I go from adjustable focal length 28mm to 108mm, as well as the stock 50mm lens. Also included was a small tripod, and a remote trigger cable, useful for long exposures.

I shot a lot of pictures with that camera while there, including a lot of long exposure shots of the aurora.

Later, I took a practical photography class in college, which open up the university's darkroom to me. I shot and developed a lot of b&w 35mm film using that camera and that darkroom, including a bunch of "push developed" shots theater rehearsals.

Over the next many years, that was my working camera.


When I finally went digital in the early 0's, that camera went into a box, where it sat in the dark. Occasionally ove the years, it would get unpacked, and then packed into another box, for another long dark wait.


Finally this weekend, it was unpacked, and then listed on a neighborhood "free stuff" group, and was picked up by the mother of a teenage girl, who is going to use it for a practical film photography class in the local high school.

I'm glad the class is making them use film, as a way to focus attention. And I'm glad that camera, that brought me so much joy and recorded so many memories and places, is now being used again.

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I have no idea why I'm considering doing such a crazy thing, but I'm considering starting and running an APA.

How an APA works:
* You write or draw on up to two sheets of paper, double sided.
* You send it to me, either via postal mail or email PDF.
* I collate them all together into a stack.
* I photocopy and bind the stack, making N copies. Enough to send one in the postal mail out to each member.
* I mail a copy to everyone.
* You get it the post. You read and enjoy it.
* You write or draw on up to two sheets of paper...

Some notes:
* I'll be willing to cover the copy costs and postage, at least until it gets too expensive.
* I'm willing to have members with non-US international addresses, again until it gets too expensive.
* Other members will not see your postal address, unless you yourself decide to put it on one of your pages.
* You can send your contribution in as a PDF, or as an actual sheet.
* Paper size has to be 8.5x11. Print will be B&W photocopy.
* I reserve the right to change number of sheets members get to send in
* I reserve the right to cap the number of members
* I reserve the right to drop any contribution, and I reserve the right to evict any member.
* The COC is: don't piss me off, don't virtue signal, content needs to be kid-friendly and safe-for-work.
* Topic is general, anything you want to write or draw. Fiction, non-fiction, gonzo journalism, bad poetry, good drawing, ...


So, if I decide to do this, do you want in?
Reply here, or msg me, or email me.

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I've noticed that I pronounce "K" and "Q" differently.

K is shorter, Q is longer.
K is harder, Q is softer.
K is started with a full stop, Q is not.
K starts and stops. Q is practically a sibilant, and I can drag it out.
Between the two, my tongue makes a different shape and touches the roof of my mouth in a different spot.

Now I need to find an expert in Phonetics, to tell me the IPA symbol and name for my K and Q sounds, and to tell me if this is idiosyncratic or not.

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 Anyone remember those scenes from ST:TNG that showed the captain doing paperwork at his desk? He was using a display terminal to read text and to do vtc, AND he was switching between half a dozen data tablets? Remember how conceptually silly that was?

My edc backpack contains a laptop, a tablet, two phones, and one and sometimes two eink reader tablets. My nightstand has two eink tablets on it, and charger points for the phones.

I just saw a coworker sitting at a table in this building talking on one phone, reading email on her laptop, consulting text on a tablet, and taking notes on a ReMarkAble tablet.

The conference room I'm in right has all my edc gear, plus a yuuge 75inch vtc display on the wall, with attached steerable camera, and a glass tablet on the table for controlling the vtc. Plus a multipoint polycom rig on table. And plus an Alexa for Business terminal on the table. Even the lightswitch isn't real, it is a multiibutton scene controller. At least the clock on the wall is a physical moving-hands analog, but I know it gets set and sync remotely via some wiring coming out of wall behind it. And the six 5'x8' white glass whiteboards lining the walls are not "smart". Yet.

We are within striking distance of ending the blizzard of paper that used to engulf work, but now we're being buried in sheets of colorful glowing glass.
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Current Location: Amazon Doppler, Seattle WA

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If you have an account that can be reset with your phone#, and that account becomes valuable, that account and that phone# will get stolen from you. It's only a matter of time. The tech companies who say this isn't a thing, they lie.

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The tech press so excited about Google's "Titan" hardware token, and the breathless statement that they have "never had an account takeover" since rolling it out internally. They are excited about the wrong things, and are being taken for a ride by G's marketing and PR departments.


It's only a FIDO U2F token. I've had one for almost 2 years now, and my current employer issued me one on my first day of work, over a year ago. Mandating 2FA across an enterprise is hardly a new thing.


The actual stories here are:

* why did Google decide to cut out YubiCo?

* Was it price?

* Was it not-invented-here?

* Did Google not trust YubiCo to not backdoor the YubiKey tokens?

* Did Google want to put their own backdoor into the Titan tokens?

* Did Google license YubiCo's manufacturing patents? (If they did not, it will be really hard to manufacture them cheaper.)

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As we were riding from Versailles back to Paris, there was sitting a few seats back from us a young attractive vivacious couple being young and attractive and vivacious with some other young attractive vivacious travellers, switching freely between Spanish and French.

And then the ticket inspectors entered our car. After the inspectors checked our tickets, they moved down to the next bench, and the saga began.

Suddenly, the couple only spoke English, and did not understand French. And... they didn't have tickets.

And they could not consistently explain how they had passed through the gates at the station they had boarded at. And could not describe what class of tickets they had had, how they had paid for them, who they bought them from, where a receipt for them may exist. For a while there was evolving story about how some tickets they had bought from some "agency" had not "registered" and so a station staffer had let them though the gates. The inspectors were not buying any of this.

I mean, jeeze, if you are going to lie about it, be consistent with your lie, and have your story straight ahead of time! Something simple like "we bought them for cash, and didn't realize we had to keep them with us while on the train", instead of a complex and evolving confabulation.

The other young attractive and formerly vivacious people sitting on that bench with them were looking agonizing embarrassed, eyes down, skin flushing, they wanted to be anywhere else, sitting near anybody else.

Then the couple offered to buy necessary tickets then and there. The inspectors agreed that yes, they were going to buy the tickets, AND they were going to pay a €100 fine. Each.

Oh, but they didn't have that much cash!

During these events, the young woman's sleeveless blouse was getting adjusted lower and lower, to reveal more and more light coffee colored décolletage. The inspectors were not buying that, either.

Oh, you don't have a credit card, bank card, or bank account? Anywhere? That's okay, the inspectors can just impound your passports as collateral. And then there will be an additional €120 charge for recovering your passports. Each. And if you don't have passports to use as collateral, then the police will get on at the next station to take you off to hold in jail as collateral for the fines.

Suddenly, they had money. A payment card was produced, inserted into the one of the inspector's handheld terminal, which then printed a receipt and two train tickets. Then the inspectors moved on to the next car. The couple was a lot less vivacious for the rest of the ride into Paris.

I hope that €200 fine was worth jumping the gate to avoid buying a pair of €1.20 tickets.

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It is easier to puzzle out a sign that is written in both Catalan and in Castilian, then it is to puzzle out Spanish on it's own. And it's a lot easier to figure out the Spanish to English mapping when the sign is written in Catalan, in Castilian, in French, and then again in English.

It was also interesting to notice just how much more common spoken Catalan is than Castilian in the streets, shops, and tapas places in Barcelona. And how much more prevalent the Catalonian flag is than the in-theory legally mandated flag of Spain. And the yellow ribbons everywhere, attached to every building, painted on every street, and wore by many many many people. And outside of Barcelona, in the countryside, it got even more common and even more blatant.

It was also interesting to notice that most of the text inscribed on the doors and walls of the Basílica is in Catalan, not Castilian.

We asked one of our guides how Catalan had so robustly survived. His answer: all the hundreds and hundreds of villages that were a hard walk from the main roads. The kings and then later the junta could pass all the decrees they wanted to, but they couldn't control the language spoken in the villages.

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While all the memes and comments about Mr. Musk's girlfriend are moderately funny, I can't help but notice that all the ones I've seen have a strong erasure of the fact that Ms. Boucher has agency.

She's not dating him against her will. He did not purchase her out of a catalog. He did not order his EA to obtain her. He did not hire Cyrano to ghostwrite poetry to woo her. She is not a 22yo intern being molested with a cigar over the Resolute Desk. Her friends did not strap her down to a table and get out a branding iron.

Why is everyone so twisted up about this? I don't get it. Is it that only guys who look like Eric Draven are supposed to date girls who look like Ms. Boucher?

He told a obscure joke that only a very narrow sub-population of very well read students of 21st century philosophy of science would get, and she got it. That's a better "first flirt" than most.
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