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Comment Re:Not so fast... (Score 1) 172

There is probably a very good reason when going up against "the bad guys" you only trust thermite, and going up against internal investigators and auditors, "trust us, writing zeros is good enough"

It depends on the drive technology. If you were in the service in the 1970s/1980s, where hard drive tech was MFM or RLL or similar, then yes, thermite was the correct option. For 2011-era SATA drives, zeros are almost good enough, and overwriting with a random data stream is most definitely good enough (the amount of time and equipment needed to try to recover a modern drive that has been overwritten with a random data stream is so prohibitive that it is usually easier and cheaper to just threaten someone with harm to coerce information out of them).

Comment Re:Calls the controller's attention to each sector (Score 1) 445

Based on how I understand the Wikipedia article, I believe SpinRite is just a stronger version of the CHKDSK "surface scan". It reads each sector a few times (or a lot of times if the sector starts to return uncorrectable errors) and writes it back.

This is true, but Spinrite's actual benefit for MFM and RLL drives was to write the data back after a low-level format of the track. This was the real benefit, since different controllers laid out data differently and the only reliable combination was a low-level format with the controller you actually plan to use the drive with . Spinrite didn't do anything that the controller's own setup routines couldn't do; it just had a nicer interface.

Comment Re:This is a big deal! (Score 4, Informative) 249

That seems like an oversimplification since the DEFLATE algorithm includes a huffman encoding step, and it is within the specs for the compressor to simply never emit back-references. It would be a horrible bug in the implementation of zlib to have worse compression performance than a basic huffman encoding.

(DEFLATE doesn't use Huffman, it uses Shannon-Fano as it's entropy encoding step.) While zlib can be configured to not emit back-references and just entropy-encode the input, PNG does not use this mode. I suspect it was because they were trying to stay as far away from the Unisys patent as possible (meaning, "image -> entropy" (GIF) and "image -> filter -> entropy" (PNG) might have seemed too similar/infringing).

zlib can not only compress worse than just entropy; if unchecked, it could actually output "compressed" data that is larger than the original. This happens when you give it uncompressable data and it tries to match patterns anyway. Of course it has a check for this; if the output is larger than the input, it just stores the input uncompressed. 7-ZIP LZMA doesn't have this, so that's why 7-ZIP's output can sometimes be larger than the input. (They fixed that in LZMA2.)

Comment Re:This is a big deal! (Score 5, Informative) 249

I didn't realize it was even possible to make such a big improvement in lossless image compression.

You falsely assume that PNG was state-of-the-art in lossless compression. PNG took a great idea (filter the image and take advantage of the 2-D correlation present in most real-world images) and coupled with it a terrible idea (zlib for the back-end compression of the filter output). You're supposed to do order-0 compression (ie. statistical, like Huffman coding) on the filter residuals, not pattern-match searching (zlib). zlib is a great piece of software, but like all tools, there are things it is very well-suited for and others it is not well-suited for. This was a misstep by the PNG team.

The choice the PNG people made was fueled by the Unisys GIF/LZW patent of the time, and at that time IBM also had a patent on range coders. So I guess it's understandable why they didn't use those order-0 methods on the filter residuals. But it was a huge mistake to knee-jerk away from ALL statistical methods and choose zlib as the back-end. They could have used basic Huffman; not sure why they didn't.

Comment Re:End of the HD era? WTF are you talking about? (Score 1) 267

Does 4K at 24 fps look more real than 2K at 48 fps? I'm looking forward to The Hobbit shot and projected like that.

I'm not. 48fps and higher looks like videotape. Nothing cheapens up what you're watching like full-field video. I'm not against video; I insist on 60 images per second when I watch a sporting event. But a fantasy movie in a theater should be 24fps.

Comment This happened to me as well (Score 1) 380

And the lesson I learned is never to bring your USB microphone with you in your carry-on. It turns out that TSA employees get a little nervous when the x-ray machine picks up what looks like a metal cylinder with lots of electronics stuffed inside.

The microphone in question was a Blue Yeti, and the only reason I still have it in working condition is because I had it packed in its original box+styrofoam (they googled it and saw it was a legit microphone).

Comment What's wrong with a spiral? (Score 1) 514

I've always mowed my lawn in a spiral that starts at the outer edge and works in a spiral towards the center. It's irregularly shaped, but there is little overlap.

I see the article proposes a solution which cuts (pun intended) about 1-2% of the time off of a spiral. When I'm cutting my lawn, I want to get it done, not do complex math during the process. A contracting spiral is obvious and effortless.

Comment Re:Easy reason (Score 4, Insightful) 533

I think the reason the community is shrinking is because Wikipedia, at least the English version, is complete. I'm not implying that there isn't more information that can be added, but as far as the sum of human knowledge goes, I'd guess that they have gotten past that "magic" 95% marker for easily acquired knowledge.

Until the cancer of "not notable" is gone, it can never be "complete" (not 95%, not even 50%).

I've seen articles on an entire range of software get deleted, while the page for Luke Skywalker goes on forever.

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