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Xerox Photocopiers Randomly Alter Numbers, Says German Researcher

GoRK JBIG2 (290 comments)

I haven't even read this article and I know the culprit exactly: JBIG2.

The compression algorithm operates on binary (2 color) images and has two modes, a lossless mode which is sort of like the love child of RLE and JPEG and a higher compression mode which operates by running the lossless blocks through a comparison routine and discarding and replacing any blocks that are sufficiently similar with references to the first copy. It's actually a good algorithm, but you have to understand how it works to implement it properly. When you have a perfect storm of certain fonts (especially small ones where a glyph can fit perfectly inside a block), have some noise in the bitonal images and have the compression threshold too high you can get some real zingers.. 9, 6, 0, 3, and 8 can all easily get muddled up, not to mention what happens to letters like e o c etc. The key to the whole thing is having good algorithms that can produce quality bitonal images from poor originals and scanning at sufficient resolution (or lowering the compression threshold enough) that blocks cannot hold an entire glyph.

As to why the copier is using the lossy mode of JBIG2 internally is mystery, especially in the "copy" pipeline. I can think of no good reason that it should use anything other than the lossless mode or uncompressed data.

1 year,16 days
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Interview: John McAfee Answers Your Questions

GoRK Re:Interesting (239 comments)

I'm curious why you like that interview so much; reading that is when I realized that that dude is nothing more than a talking head. Why do you think he needed the Internet to do commentary for Iron Chef America? IIRC he not only got a question about cooking with lava completely wrong, but he insulted the person asking as a way to avoid answering it. When Google failed him, he just bailed.

about a year ago
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US IPv6 Usage Grows To 3 Million Users

GoRK Re:IPV6 on AT&T Residential DSL (155 comments)

AT&T is not issuing you an IPv6 on your residential DSL. I know this because they don't do it. Your computer is generating an IPv6 link local address. Depending on your router and a couple of other factors, you may (probably can) access IPv6 sites using a public 6to4 gateway.

The only advantage to you is that you at least have the ability to access Internet resources that are only available via ipv6, but currently I would imagine that there are probably not any that are particularly relevant to you.

about 2 years ago
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DynDNS Cuts Back Free DNS Options

GoRK Awesome! Finally. (223 comments)

I think this is great news. Maybe router manufacturers will now be smart enough to simply include DNS Update (RFC 2136) support instead of the proprietary dyndns garbage. Enter your domain name and a key and you're all set.

more than 2 years ago
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Apple, Android Devices Swamp NYC Schools' ActiveSync Server

GoRK Overblown (205 comments)

$1MM of iPads represents about 2500-3000 users depending on the discount they received. First, I'm presuming that these users already had mailboxes and it's just the additional load of ActiveSync that is causing the trouble. If that's the case, with the types of discounts that government and education receive from microsoft and hardware vendors this is like a $15,000 problem at best. In the scope of a million-dollar project a 1.5% budget problem represents poor planning, but I've seen much much worse.

more than 2 years ago
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Ask Slashdot: Parallel Cluster In a Box?

GoRK Passive cooled GPU (205 comments)

Don't use high end GTX cards; twice as many lower end passively-cooled GPU cards will provide more than the equivalent performance with far less cost and failure rate. If your application really benefits more from additional threads vs single thread execution speed, this is the way to go. Most GPGPU clusters that aren't built using Tegra use this approach.

more than 2 years ago
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Mozilla Rejects WebP Image Format, Google Adds It

GoRK Re:Why? (262 comments)

You would be surprised; JPEG2000 is used extensively by high-compression PDF. As a standalone image format it's pretty lousy but for scanned documents it's actually really great. We have literally millions of pages stored this way where I work.

more than 3 years ago
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SETI@Home Install Leads To School Tech Supervisor's Resignation

GoRK Re:But weren't they on anyway? (621 comments)

Wait, you really don't believe this? I have a kill-a-watt and can assure you he speaks the truth. I don't have a ridiculously high end computer, but I can get its power consumption to vary by more than 300W between it being idle + LCD's in DPMS power save and me actively pushing the cpu and gpu with something. Putting it into S3 suspend will break off another 50W or so.

Now 10 year old hardware pushing 40W delta between unloaded and loaded not including a CRT going to sleep or something? Doubtful. Maybe 15-20W tops. But then again some of that school district's hardware was much newer and $0.06/kWh is a pretty decent utility rate too. I'd say $1 million is a pretty good round number here even though it probably represents a modest 10-20% increase over the bill were 5000 machines simply left on and idle. But consider if this guy who had enough control to install software on 5000 machines had simply set them to go to S3 after a couple hours of not being used? He could have saved the school district millions on power just as easily as he wasted it.

more than 4 years ago
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Radar Beats GPS In Court — Or Does It?

GoRK Re:Standard Calculus (369 comments)

The real answer here is it depends a great deal on the GPS itself, then it depends on how whatever software is reporting and logging this information post processes it.

GPS itself is capable of reporting an instantaneous velocity vector calculated by measuring the doppler shift from each satellite. (Comes in as a GPVTG sentence in the NMEA data) So if the receiver is tracking a lot of satellites with a good distribution and there isnt a lot of multipath problems, the accuracy of this vector is ridiculously good. Also, a receiver may not support GPVTG.

Now you can also get velocity data from a GPRMC (ie normal position data) sentence too. According to the specification, the bearing here is supposed to be calculated based on position track angle (presumably so that you dont have to be moving to have a GPS bearing).. The spec seems silent to the origin of the speed reported in this sentence -- seems like it could be calculated as track speed (average speed over the interval) but could easily be reported as instantaneous speed as well.

Of course I haven't tested any, but I imagine in practice, GPS receivers would normally report track/position averaged data in GPRMC and instantaneous data in GPVTG. Any software that is supposed to present this data to a user would have to determine how to aggregate and filter it to provide for its intended purpose. If you really intend to beat a speeding ticket with GPS I would suggest that you need data points of either type (instantaneous or averaged) with at least 1Hz if not 5Hz granularity along with knowledge of what the data represents and how the raw data is filtered and processed. This 30s interval business in this case is just dumb, and nobody ever bothered to determine anything about the nature of the data it seems.

more than 4 years ago
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(Near) Constant Internet While RV'ing?

GoRK Re:Iridium? (438 comments)

Thank you; very good information here; I didnt realize a station had to reply inside of the same frame. There IS therefore a timing issue but the BSS could counteract it obviously as you said by maintaining an additional frame offset internally. So this explains a 35km limit on GSM itself but do the 3g GSM technologies attempt to pack additional data in by shortening the guard period? If so that would explain a smaller distance limit, but I don't think data would be rejected; seems you'd just fall back to EDGE or GPRS?

more than 4 years ago
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(Near) Constant Internet While RV'ing?

GoRK Re:Iridium? (438 comments)

You are sure of this? Can you give some reference material? I would really like to know how or why this is true. I have hit EDGE data over some pretty impressive distances (10 miles) with the proper equipment. I really can't see how the BSS would reject a distant signal if it were good enough. The distances aren't great enough to cause any timing issues.

more than 4 years ago
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Game Over For Sony and Open Source?

GoRK Re:Who Cares (364 comments)

Since the Linux kernel only interfaces with the virtualized devices presented by the PS3 hypervisor, and since this hypervisor presents exactly the same interfaces to GameOS as it does to OtherOS (where it simply blocks many hypervisor calls) this is exactly what I'm suggesting. No shit!

If Sony is actually realizing cost savings by dropping this feature, it's certainly not happening in development, but in QA, Support, and Legal. It's still sad to see it go, and I hope they bring it back.

more than 4 years ago
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Game Over For Sony and Open Source?

GoRK Re:Who Cares (364 comments)

They still have to support the feature on "Fat" ps3's so the software engineering and support cost is there regardless of the new model. The Hypervisor itself is at the absolute core of the PS3 regardless of whether or not it's hosting the XMB, GameOS, or OtherOS, so the software is basically running on the PS3 Slim already. I believe very strongly that there has not been a hardware change that would have affected supporting the OtherOS install and that this is a deliberate move by Sony to remove a popular feature. With the PS2 slim at least they were able to pass off dropping Linux support as a semi-legitimate hardware problem.

As to why they did it, I can only speculate. First, I think that Sony may believe that an exploit may be discovered in the Hypervisor that could open the door to piracy (a la the PSP). Secondly, the rumor is they are still losing money on the hardware. If this is true, given the price reduction, smaller size, and lower power requirements of the PS3 slim, it actually becomes more attractive to build into HPC clusters. Sony may not in this economy wish to hemorrhage millions of dollars building these inexpensive supercomputing clusters all over the place.

more than 4 years ago
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Behind the 4GB Memory Limit In 32-Bit Windows

GoRK Re:Wa wa what? (756 comments)

Not only can you enable it, but it's enabled by default. You can actually boost performance (significantly) on the versions of windows that are capped at 4gb by disabling it, since accessing memory using PAE requires an extra clock cycle (3 instead of 2, for direct access)

more than 4 years ago
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Electric Company Wants Monthly Fee For Solar Users

GoRK Re:Connection fees are pretty common (367 comments)

I think the point is probably that the "base" fee currently charged to all customers is likely not indicative of the true cost of the connection and some of that cost is incorporated into the kWh fees to more fairly distribute the charges to customers of different sizes. For example, a commercial business with 200A service actually costs about the same to connect to the grid as a residence with 200A service, only their actual usage might be 4 times higher. Likewise the cost to connect a single rural customer with 200A service might be astronomical even if actual usage is minimal.

I would think a better model might be to establish minimum fees that more closely resemble the true costs of connection. Say your "base fee" is $20 but your connectivity actually costs about $100 net to the power company -- Well you are going to need to offset this difference some way -- either by buying $80 of power from them or by giving them $80. In the case of solar customers, this would be an incentive to reduce their grid connection by taking smaller grid service (or no service) or reducing their energy consumption in order to put enough power back onto the grid to offset the fee.

about 5 years ago
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Electric Company Wants Monthly Fee For Solar Users

GoRK Re:Similar logic (367 comments)

In your analogy, please don't forget that you'd also be obligated to buy my leftover groceries. However, since you don't know how much I might send back, you have to pay to mail me a big box every week, which I may or may not return.

about 5 years ago
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Pickens Calls Off Massive Wind Farm In Texas

GoRK Re:A fool and his money are some party (414 comments)

This is a little misleading because he didn't hope to build his own transmission lines; that was never in the cards. He hoped that he could force utility companies and taxpayers to build them for him. That was the reason for his massive ad campaign. His project would only be able to turn a profit if the public had been willing to waste a hundred billion dollars or more on infrastructure to support it.

As great as wind power might be, if we as taxpayers want to spend that kind of money on sustainable energy, there are far more sensible investments.

FWIW I hope he loses his shirt selling the turbines. For pennies on the dollar, they will be a good buy and arguably far more useful spread around to places where installing them is economically sensible.

more than 5 years ago
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AT&T's Bad Math Strikes MythBusters' Savage

GoRK Re:Soz this mean we get a cellphone special now? (305 comments)

I honestly think this would be a better topic for Penn&Teller Bullshit to cover, particularly text messaging charges.

I did however dig out my cellphone bill from about 15 years ago. Somehow I don't remember things being as bad as they were because my bills in 1994 dwarfed my bill today.

more than 5 years ago
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Confirmed Gmail / Google App Outage

GoRK Re:Forcing denial of service on unrelated sites (189 comments)

You're telling me; I start getting reports from users all around the office that sites are failing to respond -- looks like a bigtime BGP barf, but then I realize it's all google ads and google analytics hanging pages all over creation. I couldn't think of a good way to mitigate this other than to blackhole Google's Georgia datacenter, and I figured by the time I did that, Google would have it fixed. Imagine my surprise when they didn't after a few hours. I guess there's a first time for everything.

more than 5 years ago
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CFLs Causing Utility Woes

GoRK Re:Going a step further (859 comments)

http://en.wikipedia.org/wiki/Luminous_efficacy

If the data there is current, LED's max around 100 lm/W (15%), CFL's around 72 lm/W (11%), high efficiency fluorescent around 120 lm/W (18%) and things like low pressure sodium (orange-hued street lamps and the like) around 200 lm/W (29%). Incandescent hang out in the 5 - 18 lm/W range (~ 2.5%)

So right now in commercial products, the expensive LED based bulbs built with very good LEDs offer about the same performance as CFL's and usually are outperformed by your standard fluorescent fixtures. They do actually last a great deal longer and are arguably more environmentally friendly. They are easily justified by any installation where changing a bulb costs considerably more than the bulb (such as commercial installations requiring scaffolding to accomplish the feat). However the LED bulbs you can find in the retail stores these days that represent that a 5W LED bulb compares to a 13W CFL and a 100W incandescent are telling absolute lies. Then again, most retailers wouldnt dare put a decent $120 LED bulb on the shelf either - it simply wouldn't sell.

IMO the whole system for advertising bulbs is broken. If there's going to be any change to the laws about lighting it should not be to ban the sale of incandescents but to require better labeling. If bulb packaging were required to display the luminous output, the power consumption, and the color temperature we'd all be better off. There is some other useful information they could put in there too such as PF, weight, hazmat, lifetime, etc. -- sort of a "Nutritional Information" for bulbs. They already require similar labeling on appliances but I could see this type of requirement really helping out on power consumption. Once that garbage battery charger has to actually put a label on its box that says it ships with a crap 10% efficient wall wart that draws 300mA idle is the day it will instead start shipping with a better power supply.

more than 5 years ago

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Incredible - SNES Emulated on GameBoy Advance!

GoRK GoRK writes  |  more than 10 years ago

I just discovered that a SNES emulator for the GBA that will apparently run at "Playable" speeds is currently in development and fairly close to an initial release by none other than Loopy, the fellow who brought us PocketNES, the absolutely incredible NES emulator. PocketNES was the reason I bought a GBA in the first place.

There is apparently a video demo floating around out there somewhere, but I was unable to locate it. The emulator runs without sound (at least currently). Porting games is one thing, but it's quite amazing that that a system with such similar capabilities and specifications can be emulated on the GBA with all the extra things that have to happen to make things work. Take a look at the specifications:

SNES CPU 16-Bit CPU - 3.58mhz
GBA CPU 32-Bit ARM - 16.7 mhz

SNES Work RAM 128 Kb (CPU internal)
GBA Work RAM 256 Kbyte (external to CPU)

SNES Video RAM 16Kb (CPU internal)
GBA Video Ram 32 Kbyte + 96 Kbyte VRAM (in CPU)

SNES Total Colors 32,768
GBA Total Colors 32,768

SNES Onscreen Colors 256
GBA Onscreen Colors 511 (character mode)

SNES Colors in Bitmap Mode 256
GBA Colors in Bitmap Mode 32,768

SNES Resolution 256x224 (512x448 hires)
GBA Resolution 240x160 fixed

SNES Sprites 128 Max size 64x64
GBA Sprites 128 Max size 64x64

SNES Scrolling H, V, Diag
GBA Scrolling H, V, Diag

SNES Sound 8-bit 8 channel Sony
GBA Sound 8-bit 2 channel + GBC sound

SNES SRAM Available
GBA SRAM Available

SNES Max Cart Size 48mbit (6MB)
GBA Max Cart Size 256mbit (32MB) (Flash carts to 128MB with bank switching)

Update!

I found the video. You can get it here -- while the link stays up anyway...

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Spam is getting desperate!

GoRK GoRK writes  |  more than 10 years ago

Well, it looks like the spammers are getting desperate as the filters are getting better and better. Despite receiving on the order of >300 spams per day to my various accounts, here's a sample of a spam that still manages to make it through the filters:

Date: Fri, 03 Oct 2003 00:20:59 +0000
From: Nifepezil
Subject: Gork, with my little helper my life becomes so sweet :)
To: Gork

Hey, !

Deborah is here :) 89 . I felt so lonely every day - but today everything has changed.

759923888220267
with my little helper my life becomes so sweet :)

614609363648
we, women, deserve it :)

I hope to meet you among us :)

Deborah

Boy howdy! I hope this is a misdirected spy communique because it sure as hell is a shitty advertisement for whatever it is that I'm being sold. Spamassassin rocks!

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Dimensional Warp Generator Needed

GoRK GoRK writes  |  about 11 years ago

Generally the message begins something like this:

Hello,

I'm a time traveler stuck here in 2003. Upon arriving here my dimensional warp generator stopped working. I trusted a company here by the name of LLC Lasers to repair my Generation 3 52 4350A watch unit, and they fled on me. I am going to need a new DWG unit, prefereably the rechargeable AMD wrist watch model with the GRC79 induction motor, four I80200 warp stabilizers, 512GB of SRAM and the menu driven GUI with front panel XID display.

What follows is generally a way to contact the spammer either by email, postal mail, fax, or in-person meeting.

I have gotten an increasing number of these lately in various forms. I told my friends about them because they were so funny, and everyone has been forwarding me different forms of the message for a couple weeks. I have amassed quite a few different versions now, but I can't figure out what the hell the scam is. Does anyone know? Apparently this message has been going around for a number of years, but I haven't been able to find anything about it. I thought snopes would have had something, but they are no help.

The only thing I can think of is that some fool might get excited about it and, believing that such a device actually exists, attempt to contact the spammer to purchase some advanced technology at which point a regular con ensues. Ie. money given up front; scammer run away.

The other side of the coin is to theorize like this:

If time travel is to ever exist, then the likelyhood that someone will get stuck in the past at some point is almost certainly approaching a 100% probability. Now, if this were the case, then a person's best course of action would be to contact the largest number of people in the most historically inconspicuous manner possible. I think that spamming millions of people through e-mail is definately the right way to go about finding a replacement device of some sort. The possibility (however small) that this whole thing is actually true does actually exist! Poor guy. What a terrible time to be stuck in...

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Videogame Vertigo

GoRK GoRK writes  |  more than 11 years ago

I have played videogames since I was a little kid. My folks had gotten a ColecoVision as an upgrade to their aging pong machine about the same time I could start to play some of the games, and so it began. I have owned a lot of the console systems since then and played a good number of computer games. I'm good at a lot of games and bad at others, though I haven't ever really played a game I couldn't finish if I really wanted to. I was playing a new game the other day when I realized that there are a lot of games that I really hate for one very strange reason: You can die by falling into infinite nothingness.

In real life, I'm not scared of heights. I can lean through the bars on top of the Empire State Building and look straight down. In video games, I can handle falling off of a building. I can handle falling into molten lava. I can handle climbing all the way to the top of some insurmountable peak and falling off just to do it all again. But I simply hate falling into infinite nothingness in a video game. It irks me to no end. I clamp up in Mario 64 or Super Mario Sunshine whenever I have to play one of those levels where you have to balance on narrow beams while you hop from block to dissolving block. I get sweaty hands so bad when playing Super Monkey Ball Jr. that I have to keep pausing it and drying my hands and the GameBoy.

Maybe the game companies could put some sort of option to add a floor in any game where it is possible die by falling into some infinite void. Instead of falling into a void, you would fall a short distance into a spike pit where you would be impaled instead. That would be better for people like me. Call it "Videogame Vertigo" if you want. I have it, and the current rash of 3D games give me the creeps. Won't someone put some warning labels on these packages?

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My Experiences with Kite Photography

GoRK GoRK writes  |  more than 11 years ago

Some of you may remember the article that Slashdot ran recently on Kite Aerial Photography. Many times I read about something cool thinking "oh hey that'd be a neat thing to get into," but never have I actually done anything about it until this time.

To make a long story short, my friends and I built a photography rig and got some kites large enough to lift it and have been flying and taking photos for a couple of months. It's a fun hobby that (for me anyway) blends the correct amount of technical wizardry with being outdoors in the sun. You start on almost any budget and there's always something new to try (video, stereo photography, panoramics, etc.)

I recently took the rig and kites with me on a trip to Hawaii and flew at a few locations on Maui. I am very proud of the shots, even though I'm by no means an accomplished kite flyer or photographer.

Please have a look at the website that I have put up with photos and info about what my friends and I are doing. There is a lot more that I intend to put up when I next get around to it. I'd be very interested to hear your comments. You can post here or there if you feel so inclined.

And, by the way, if you read the slashdot article and thought that kite photography would be a fun thing to try and have since forgotten about it, go back and DO IT. You will not regret it (unless maybe you drop a nice digital camera a few hundred feet like we did...)

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