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Comment In the lab working on a space shuttle simulation (Score 1) 320

I was really into the space shuttle--I used to build models of various proposed space shuttles when I was a teenager into model rocketry. At the time of the disaster, I had found my way into a program in the psych department at the local community college that tried to study the effects of living in enclosed spaces by using a space shuttle mockup built out of plywood, TV monitors, some Atari 800s and electronic hardware from the surplus yard down in Taunton. It was very not realistic, but at the same time not bad--apparently it felt very convincing to the people who were in it.

So needless to say, we were all pretty wrecked. I don't know how many times I watched the explosion on the instant replay, but it was a lot. Lots of crying, very maudlin, but on the other hand the lot of us were able to hang out together and grieve with people who got it. Looking back on it, it's a funny coincidence that we were all there when it happened, but we were.

Comment Re:Why retail? (Score 2) 298

In principle they have to maintain less, so it's a win. In practice, it's early days for new generation mechanisms like solar, despite the rather terrifying amount of capacity that we now have. When everybody has panels, we'll have to have some way to pay for the grid, so obviously net metering _by itself_ doesn't scale, and particularly in states with lots of sunny days, this kind of adjustment was inevitable.

Comment There are issues with this... (Score 2) 247

More memory doesn't necessarily make things faster if you have multiple streams and limited bandwidth. You can wind up with a situation where you have a lot of data queued in the buffer, and this botches TCP congestion control so that you wind up getting really poor throughput. Google "bufferbloat" for details. Using a crappy external wireless AP makes this worse. You really do want the wireless card to be treated as a first-class network interface on your router. Unfortunately, wireless drivers are usually closed-source, often have internal bufferbloat problems and other bugs, and can't be updated.

The article's main point, that a faster CPU in the router is wicked awesome, is completely true, of course. You just want to make sure you're running a recent Linux kernel that does a good job of queuing in the presence of a congested link. :)

Comment Goldbach conjecture (Score 1) 140

In HS, finding the two primes that add up to an even number was the most memorable assignment. The teacher had a bet that anyone who could write a faster program than his would get a prize ... but his was always faster for any number over a million or so. It wasn't until the next semester that I figured out that the key was to only loop until the square root of a factor before deciding it was prime.

Comment Re:Sanctions lifted ... (Score 1, Interesting) 229

The Chevy Malibu is a good example: the 2010 model was as good as any in its class and better for North American driving conditions than most of its European- and Japan-optimized competitors. I haven't seen the 2016 yet but early reviews are that is it substantially improved over the 2009-2011 type. There are many very good Big 2.5 designed and built models on the market that are competitive with anything (particularly in North America). Also some not-so-great models - which is also true of Mazda, Toyota, Nissan, etc (not even getting into the VW cult/mess). Toyota automatic transmissions? Woah, there's a great design ;-(


Comment Re:I have done my own comparisons (Score 1) 110

This is because release groups are completely, utterly clueless about video. The file size is set ahead of time. Most groups set e.g. "8GB for 1080p movie", "4GB for a 720p movie" etc. in x264. Historically speaking, these pre-selected sizes were designed to fit on different media types, such as CD, single-layer DVD, dual-layer DVD.
Few people use DVDs anymore, but most groups still make files far larger than they need to be.

I rarely download pre-made videos because of this, so haven't downloaded any encoded in h.265, but I suspect they simply chose a smaller pre-set size.

The correct, non-stupid thing to do is to set the quality and let the movie be however large it needs to be, usually under 4GB. This allows more easily encoded video, like CGI films (Toy Story, etc.) to be small while very difficult films (anything with a lot of noise and movement, like war films) are large but don't look terrible.

Comment I have done my own comparisons (Score 4, Interesting) 110

I have done my own comparisons of AVC (using x264, single-thread, veryslow preset) and HEVC (using x265, disabling wavefront processing because it slightly reduces quality, veryslow preset). All 1080p video, significant because HEVC is supposed to scale to 4K better than AVC.

My conclusions:

1) x265 takes FAR longer to encode, but we knew that. Understandable.
2) When "low in bits", x265 blurs images rather than making them look blocky. This sometimes looks better but to me often looks worse.
3) x265 seems to force a denoise filter. Video is far easier to encode efficiently when denoised, so I figure this is part of the data savings. It's a bit of a cheat, however, because I can get far smaller file sizes by running a denoise filter myself for x264-encoded video.

I looked closely, for example, at Captain America the Blu-ray. Much of the detail of, e.g. car leather and grass and tree leaves is lost in an x265 encode, even at about the same overall data rate as x265/

x265 supports "--tune grain", roughly analogous to "--tune film" for x264, but it makes the video vastly larger -- often larger than x264's version, and it often looks worse. It does a better job of keeping grain, however.

My experience is very similar to many others' in forums. I had committed to switching my encoding to HEVC, but the results of my tests showed it is not ready for prime time. Some may not mind blurry ("soft" is probably a better word) video, or video that looks like it has been through a denoise filter, but I do.

This is not to say that x265 is junk. I am sure it will mature over time just like x264 had to over time. x264 started out as being not all that much better than divx, the previous generation.

Comment Re:distribution of wealth and (Score 1) 729

I can't lead you by the nose to the numbers and expect you to accept them. I'm asking you to try to actually get an understanding of the problem, and then come back and tell me you still disagree with me. What you've said so far indicates that you don't actually know what the numbers are--if you did, you'd probably be outraged. It's always possible that you do know what the numbers are and think it's okay, but that's a bit hard to believe.

Comment Re:We COULD get by working 10-20 hours a week (Score 1) 729

I haven't met a lot of these lazy people of whom you speak. We see them on TV, sure, but in real life? People sometimes do not want to put much effort into the meaningless job they are able to get, but if they had the opportunity to do something they considered meaningful, they'd work their asses off. But our economy isn't structured that way.

Comment Re:We COULD get by working 10-20 hours a week (Score 1) 729

Sorry, I was insufficiently detailed in making my point. What I mean is that we have no way other than work for people who have no money to get money. Whether, and how much, you work, and how in-demand your skills are, all determine whether you can have money. So of course people work too much--it's the only way to get ahead if you are paid hourly, and it's often the only way to keep your job if you are on salary.

Comment Re:Fuck Forbes, and in particular Ethan Siegel (Score 1) 176

It's clickbait and self-promotion.

Clickbait, no: there's actual, real, high-quality content to what he writes.

Self-promotion: so what? If someone writes something interesting and informative, I want it to be brought to my attention -- even if they're the ones to bring it to my attention.

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