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Comment Re:Who, not what (Score 1) 796

Anathem rewards persistence, it's not an easy book to get into, but if you stick with it, you'll be taken on a seriously impressive journey. There's a strong chance you'll come out the other side thinking it's one of the best books ever written, and that Fraa Jad is... well, I can't say much without spoilers, but he's one of my favourite literary characters ever.

Submission + - Nmap team releases 5 gigapixel favicon map 1

iago-vL writes: From the creators of Nmap comes the largest survey of this its kind ever performed: the favicon.ico files of over a million Web sites were scanned, compiled, and sorted to create a 5 gigapixel image, blowing their 2010 survey out of the water! It's searchable, zoomable, and incredibly fun to play with! Can you find Slashdot without cheating? (Hint: it's near Facebook)

Comment Re:An O'Scope (Score 2) 215

The MHz number on the box is the bandwidth, not the sample rate. The sample rate is measured in samples per second (GSps). A 100MHz scope is probably adequate for analog signals up to 100MHz. However, if you're debugging a digital signal, you want a scope that has 3x the bandwidth of your signal's base frequency or more, because square waves are composed of the base frequency and an infinite number of harmonics. If you only have bandwidth for the base frequency, your square wave will be distorted into a sine wave and you won't be able to accurately see ringing, glitching, and other artifacts.

I have a 1GSps, 100MHz scope. I wouldn't use it for serious digital signal debugging above 30MHz (which is 33x lower than the sample rate), due to the bandwidth constraint. It's adequate for seeing if stuff up to 100-150MHz is "there" though (and for reading the bits out if you just want to use it as a poor man's logic analyzer), just don't expect to diagnose signal integrity and timing issues at those speeds.

Submission + - Google Books case dismissed on Fair Use Grounds

NewYorkCountryLawyer writes: In a case of major importance, the long simmering battle between the Authors Guild and Google has reached its climax, with the court granting Google's motion for summary judgment, dismissing the case, on fair use grounds. In his 30-page decision (PDF), Judge Denny Chin — who has been a District Court Judge throughout most of the life of the case but is now a Circuit Court Judge — reasoned that, although Google's own motive for its "Library Project" (which scans books from libraries without the copyright owners' permission and makes the material publicly available for search), is commercial profit, the project itself serves significant educational purposes, and actually enhances, rather than detracts from, the value of the works, since it helps promote sales of the works. Judge Chin also felt that it was impossible to use Google's scanned material, either for making full copies, or for reading the books, so that it did not compete with the books themselves.

Comment Re:Corrective lenses adaptation? (Score 1) 55

You can correct for chromatic aberration in software, to a varying degree. You can approximate it (so the aberration is ~1/3 of what it would normally be, by aligning the centers of the primary colors) for arbitrary inputs, e.g. a photograph captured with an imperfect lens (image editing software can do this). You can do it on the output side with perfect accuracy if you're displaying an image using three monochromatic light sources (e.g. a laser display), since the three wavelengths involved would then be distorted by three discrete amounts that are perfectly correctable. For RGB panels like LCDs and OLED displays the primaries aren't monochromatic, but they are more concentrated around the dominant wavelength than a natural light source with a uniform frequency distribution, so you get a result that's somewhere in between. This is what the Rift does to correct for chromatic aberration in software.

Uneven pixel density is only a problem if the pixel density at the sparsest point is too low. Today's displays already exceed visual acuity when viewed at a reasonable distance (e.g. a Nexus 10 or an iPad with a Retina display at a normal operation distance), though of course that is without covering a large fraction of the FOV. Give it a few more years and it'll only get better - once we have 8K phone-sized displays this will probably be a non-issue.

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