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Comment: Seems that the shoe is sometimes on the other foot (Score 1) 681

by ggendel (#49112741) Attached to: Bill Nye Disses "Regular" Software Writers' Science Knowledge

After getting my BSEE I begain my career designing integrated circuits, I soon started writing software to aid me in design and then migrated into the in-house design automation software group, working on projects such as gate-level simulations and circuit synthesis. I tried to get into the computer science program for my masters in the BIG local university. I was told flat out to forget it as EEs didn't have the necessary background to get into the program. I then went to another school where I completed masters in Biomedical Engineering, Electrical Engineering, and Computer Science. It's let me work productively with Physicists, Mathemeticians, Engineers, and Computer Scientists. There is room for all to coexist and learn from each other, but experience has made me skeptical of pretty much anything my co-worker's say until I do the research myself. That skepticism has served me well throughout my career.

I think that Bill's generalization should be taken with a grain of salt until actual data supports his suppositions.

Comment: Similar to Joe Weisbecker (Score 3, Interesting) 47

by ggendel (#48548267) Attached to: Ralph H. Baer, a Father of Video Gaming, Dies At 92

A similar story was told to me about Joe Weisbecker when he was working in the RCA research laboratories. He came to management with an idea for a general purpose video game system. After rejection, he built it anyway in his garage and called it FRED (something like fun, recreational, education device).

When microprocessors just started taking off, management came back to Joe and made FRED into it's first microprocessor, the 1801 and RCA created it's first video game system called Studio. The 1800 family had a very intriguing architecture. It had 16 general purpose registers. And by general purpose, I mean that you had to specify which one would be the program pointer, which one would be the stack pointer, and so on. You could change them at will in your program so you could switch the program pointer register to make a subroutine call with virtually no overhead as long as the last subroutine instruction put it back to the calling procedure's pointer. Putting a value in the accumulator automatically set the status flags. It took me many hours make my first 8008 program work since I was expecting the "zero" flag to be set when I loaded the accumulator with a zero value, silly me. It also had an instruction pipe so almost every instruction (except for long ones) took exactly 8 clock cycles (long took 12). This made it trivial to figure out how long your program would take (just count the instructions) or write UART functionality. It was a perfect design for a micro controller. The big drawback was cost as it was fabricated in SOS CMOS so it could be radiation resistant in satellite applications.

Joe was an interesting character. I have a book he wrote that describes how computers work by using pennies.

Comment: Re:High Resolution Stills via video (Score 1) 116

by ggendel (#48479873) Attached to: Ask Slashdot: Best Drone For $100-$150?

The term to google is "Super-resolution". Unfortunately, I wrote this a long time ago and most of the techniques were based upon image pyramid processing which my employer has patented. They used this in a product for consumers back in the early 90s from their spinoff company (now defunct) called VideoBrush. Besides super-resolution, it did real-time video stitching to capture everything from panoramas to high-resolution whiteboard capture just using a handheld camera (no tripod necessary). Pyramid processing helped in allowing real-time high accuracy alignment of images with at least 10% overlap on a consumer PC.

That said, the technique is pretty straightforward:
* Capture a number of images that overlap the region of interest.
* Align the images using the appropriate degrees of freedom (Affine should work fine here) to sub-pixel accuracy.
* Merge the aligned images. Basically, at each upscaled pixel location, average the values from the aligned images.

Comment: High Resolution Stills via video (Score 1) 116

by ggendel (#48478429) Attached to: Ask Slashdot: Best Drone For $100-$150?

If you pick up something with reasonable video resolution that can do I-Frame only then you can use multiple images to do a super-resolution still. The premise is easy... Multiple images will not cover the exact same pixel positions (unless the drone is affixed to a stationary point). You can use this fact to merge multiple images into a single one with much higher resolution than any of the single images. The more images that you can overlay, the higher the resolution you can squeeze out.

The trick is to have good alignment and warping algorithms to do the overlays. I've done this for an employer in my previous life with impressive results.

Comment: Re:iris (Score 1) 127

by ggendel (#48473283) Attached to: Ask Slashdot: Best Biometric Authentication System?

For your particular scenario iris recognition seems to be the most viable option. Iris is very fast and accurate and will not require removing gloves etc.

Iris scans are much more reliable than fingerprints. However, they don't come without issues. The capture algorithm must include:

* Dealing with occlusions. Either the top or bottom of the iris is usually occluded depending on racial origins.
* Dealing with spoofing. For this a single snapshot is not reasonable. A sequence (video) is needed in order to check for pupil pulsations that indicate a live eye. In addition, you need to do spherical eye checks so you know you're not looking at a projection. The best system I worked on used random flashes of IR illumination to cause specularities on the surface of the eye. This also aided eye positioning for finding the eye and doing these checks.
* Dealing with eye covering. Glasses and shields are a minor problem since they can distort the iris and they can reduce spoofing detection.

Comment: Delaware (Score 1) 1255

by ggendel (#44737947) Attached to: Why One Woman Says Sending Your Kid To Private School Is Evil

For most of us in the US, a significant portion of the local public school budget comes from property taxes. I was asking a realtor in DE how they deal with public schools with such a low property tax basis. The answer wasn't surprising... The majority of the populace sends their children to private schools for their elementary education but still go to the public high schools. They feel the major advantage is that the private schools compete (and therefor excel) at educating and that citizens do not pay continuously high taxes after all their children have left the school system. They still feel that their public elementary schools give a decent education because they are smaller and more manageable (thus less costly). I don't know whether this is the prevailing feeling in DE, but it seemed appropriate for this thread.

Comment: This sounds like a bad setup to me (Score 1) 190

by ggendel (#44723233) Attached to: Ask Slashdot: Speeding Up Personal Anti-Spam Filters?

If you require using sophisticated procmail filters on your personal account then it seems like your setup is wrong from the get-go. Your incoming mail server should be taking the brunt of the work and using a progressive and efficient filtering before any filtering by content.

I use a spamdyke based front end that has a whole arsenal of whilte, black, and gray filtering of emails using RBLs RBLHS, reverse lookups, etc. It also can do header "pattern" filtering as well, but I currently don't use that feature. This blocks almost all spam quickly and efficiently. The last stage is to run it through spamassassin for those things that are in the gray (not a simple reject/accept, but a cumulative scoring) area. Worst case mail delays are on the order of few seconds through the whole chain. Spamassassin only gets a small number of incoming emails to work on. The stragglers usually come via accounts at yahoo, live, etc.

The nice thing about spamdyke and other systems like it is that it does it's job very fast. For example, the blacklists and whitelists in spamdyke can be setup as directory tree structure so it is a very quick lookup to determine whether to accept or reject the specified domain or ip address.

I also use systems like honeypots and hunter-seekers. The latter looks at what is graylisted or accepted by spamdyke and does http checks on the domain to see if it should be blacklisted. It also may decide to do tests in ip address neighbors to see if more should be blacklisted.

Like all systems, you must be proactive at identifying mail that shouldn't have been rejected. It is a rare situation, but there are a few companies with badly configured mail servers (like no reverse dns entries). However, after many years of operation my whitelist contains only a handful of domains. The automated blacklist process sends me email when it adds a domain, just in case.

Comment: zfs snapshots (Score 1) 572

by ggendel (#43366951) Attached to: Ask Slashdot: Protecting Home Computers From Guests?

If you're running with zfs, just take a snapshot of the file system before handing over the system. When they're done, roll back to your snapshot. Both take seconds to perform. There may be other filesystems that can do this, but this is the one I'm familiar with and it works extremely well and doesn't require any virtual machine layer.

Comment: Re:You don't (Score 1) 683

by ggendel (#42473775) Attached to: Ask Slashdot: How Can I Explain To a Coworker That He Writes Bad Code?

I worked with an absolutely brilliant man that came out of the FORTRAN era. Two character variable names, large functions, no comments, etc. He carried this style through our transition to PL/I and then C. No one could understand his code until they understood his system, which was pretty strict. The second character identified the purpose of the variable, X was a loop counter, and so on. I supported his code after he left the company and once I got the hang of it it was actually easy to figure out where to find what you wanted.

Personally, I would never have adopted his system, but it did work for him and he banged out code quickly with minimal bugs.

Comment: Re:13 comments says it all (Score 1) 17

by ggendel (#42449283) Attached to: Open webOS Adopts Apache Cordova for Hardware Access


(Typed on a touchpad running android marvelously)

Spoken like a person that's never used a Pre 3 which I used to beat the Microsoft challenge. The only issue has been stalled development. OpenWebOS is the last hope for this work so I hope they make it a good one. Supporting existing devices is a step in the right direction. Oh, I've got 4 Pre phones in the household, plus three touchpads all hombrew patched with LunaCE and overclocked kernels. Both my and my wife's Touchpad hasn't needed a reboot in over 6 months of daily use. We tried Android and Jelly Bean comes close, but it still is clumsy compared to WebOS (especially on phones). The latest threaded email app from OpenWebOS is a nice piece of software. WebOs needs a serious refresh on the browser (ala Isis) to make it competitive again.

The main reason that there are so few comments is that HP has raised hopes and subsequently dashed them in the 11th hour so many times that the community has adopted a "show me when it becomes real" attitude.

Comment: Seems like a bad implementation to me (Score 2) 98

by ggendel (#40768579) Attached to: Reverse-Engineered Irises Fool Eye-Scanners

I worked on early iris recognition software and we had already worked through this scenario way back then. If the scanner was worth it's salt, it would be doing what we did years ago...

1) Verify that the eye reacts to changing light conditions... Pupils should contract or dilate when required.
2) Verify that the eye isn't flat (i.e. a picture). Proper specularity orientation from changing light sources (we used infrared) to identify the curvature.
3) Glowing pupil under infrared, dark with different lighting.

I'm sure there were a number of other things we did, but it has been awhile. Bottom line is that we only used a representative frame from a video sequence for the iris coding; we used the sequence to verify that what we had was not a picture, a contact lens imprinted with an iris pattern, even a live person (not a corpse).

When I left that project, we were able to do iris recognition at a significant distance even if the subject was walking fast using high speed, high resolution video capture.


Torvalds Bemoans Size of RC7 For Linux Kernel 3.5 158

Posted by samzenpus
from the too-big dept.
alphadogg writes "A host of small modifications and a large number of system-on-a-chip and PowerPC fixes inflated the size of release candidate No. 7 for Version 3.5 of the Linux kernel, according to curator Linus Torvalds' RC7 announcement, made on Saturday. Torvalds wasn't happy with the extensive changes, most of which he said he received Friday and Saturday, saying 'not cool, guys' in the announcement. However, the occasionally combustible kernel curator didn't appear to view this as a major setback. 'Now, admittedly, most of this is pretty small. The loadavg calculation fix patch is pretty big, but quite a lot of that is added comments,' he wrote, referring to the subroutine that measures system workload."

If a thing's worth having, it's worth cheating for. -- W.C. Fields