Admin: National NATIA conference

I haven't missed many national NATIA conferences over the past twelve years or so, but this year I will unless I can exploit some quantum mechanical effect on a macro scale - I can't be in two places at once. So, I'm off to points south instead of west. Enjoy the conference, you who can attend, and I look forward to hearing about any interesting a/v forensic happenings. Cheers!

Biometrics: Fooling an age verification camera

Of course, this comes as no big surprise, but it is amusing - a news reporter in Japan used a photograph clipped from a magazine to fool an age verification camera system on a cigarette machine. Link to the Daily Irrelevant post.

Human Auditory System: Experimental tinnitus treatment

Researchers at the University of Arkansas for Medical Sciences (UAMS) have developed an experimental treatment to help sufferers from tinnitus (also known as "ringing in the ears"). They report that they have successfully treated one patient using a technique known as frequency repetitive Transcranial Magnetic Stimulation (TMS). The treatment scheme involves multiple sessions of this magnetic stimulation with the location of the magnet coil being determined from a PET scan, which is an imaging technique used to see inside of the brain.

The ScienceDaily article says that 17 percent of Americans suffer from tinnitus, but I am not sure what that statistic means - is it "suffer from at some point in their lives", "continually suffer from" or what? It seems from anecodatal evidence to be "continually suffer", but that is besides the point. It will be a step forward if they have developed a safe and effective treatment.

Human Speech System: Woman acquires new accent after stroke

ScienceDaily (USA, online research news site) reports on a case in Canada of a woman who developed a new accent after having a stroke. This is a recognized medical condition known as the "foreign accent syndrome". What struck me about this particular case is that

1. the subject had not been exposed to the newly acquired accent before
2. the new accent was still in her native language (english)
3. even after two years of therapy, the new accent persists

I'm not a specialist in brain science, although I do follow it out of curiosity, but it seems to me that this case brings into question exactly how independent or dependent human spoken language accents are on our common brain structures. It seems to beg the question whether the speech-motor area in the brain puts constraints on the formation of accents, and, assuming it does (which seems reasonable), then how much? Is it entirely a matter of coincidence that the damage to her brain resulted in a new, but recognizable, accent? Why not some accent that was unrecognizable? Does the speech-motor area have some type of built-in presets that directly lead to or indirectly influece the development of different accents?

But what does this have to do with forensics, you might ask? Well, for starters consider voice comparison and subject profiling both rely directly and indirectly on understanding how the speech-motor area functions and how accents develop. Fascinating stuff!

Human Auditory System: Beaming sounds into your head

Journalist David Hambling has written in New Scientist (UK, center-left, popular science magazine) and Wired (USA, center-left, popular technology magazine) about the on-going development of a technology to beam sounds into a person's head using microwaves. This technology is not immediately of practical benefit, judging by the articles, but it is a bit of fun reading.

What I took away from these articles is that there are potential (probable?) health risks when used a high power levels, such as in crowd control applications, so researchers are looking at where it might be useful in low power applications - advertising is mentioned, of course.

As an aside, I noticed the continuation of a pattern that seems to appear with all less-than-lethal "weapons" (i.e. those technologies that seek to incapacitate, drive-off, etc, rather than kill the subjects) - namely, once you label a technology or technique as "less than lethal", this seems to consistently bring with it the hard requirement that it be 100% less-than-lethal in all conditions. Taken to its obvious conclusion, this pattern will make most, if not all, less-than-lethal development projects go bust at some point, for better or worse.

Image Forensics: New blog - Forensic Photoshop

There is a "new" (i.e. started this year) forensic blog that goes into some of the nitty gritty details of image forensics. Forensic Photoshop is penned by Jim Hoerricks, who is an experienced practitioner in the field. I've found his posts to be both very interesting and current. Enjoy!

Image Forensics: Augmenting video restoration & enhancement with a forensic artist

The math, science, and technology used in video forensic filtering and forensic video analysis can work minor, and sometimes major, miracles. However, it is not "the be all and end all", as the saying goes. This article in Forensic Magazine uses an actual case to show where a professional forensic artist was able to use knowledge of human physiology and such to generate a full frontal facial drawing of a suspect from a single frame of a security camera video taken at from the standard elevated position. Let's hear it for the liberal art majors!

Computer Audio: Pro Tools now available for Mac OS-X Leopard

Pro Tools for Leopard is out. I don't use it myself, but I know several audio forensic professionals who do and they swear by it.

Acoustics: Acoustic cloaking

First there came visual cloaking of tanks, et al. Now, there is a design idea for an acoustic cloak - I should have seen it coming (pun intended)!

Image Recognition: Military uses pattern recognition to detect bomb planting activity

I wanted to call your attention to an article by the Strategy Page on how the US military in Iraq is using pattern recognition on imagery to detect IED (Improvised Explosive Device) emplacement activities.

A very simple implementation of this technique is to take a picture on Day 1, then another picture from the same location and in the same direction on Day 2. Next subtract the two images from each other and see what is left over. All the things that did not change between the two images will disappear and only those things that changed will be left! In this case, what will be see on the "difference image" might be some disturbed gravel, tire tracks off the side of the road (assuming it is a road-side bomb emplacement) or, if the military guys are really lucky, what will be left is a bunch of guys standing around with shovels and a bomb as they work to put it in place. Neat (and helpful)!

Physics: Physics for Future Presidents

I freely admit that I am a geek. However, strange though it seems to me, I am not a gadget freak. That being said, even I was won over to podcasting. A friend got me excited about listening to university courses on-line via podcasts (thanks, Amy!). An iPod Nano and iTunes were my ticket to liberation from over-the-air radio during my travels.

With that small confession and short history out of the way, I got the urge today to share one of my favorite podcast courses with you - Physics for Future Presidents, by Richard Muller. His explanation of the issues and science around global warming alone is worth the cost of an MP3 player. You don't have to use iTunes to download it, but it is convenient if you do. Enjoy!

Admin: Teaching

As mentioned on a previous posting, I am teaching for two weeks - hence the light posting during the last week and, most likely, the rest of this one. I am, however, still moderating comments, so keep them coming!
Best Regards,
Keith

Audio Forensics: Off to a conference

The Audio Engineering Society is holding its 33rd International conference later this week (June 5-7). The topic is Audio Forensics - Theory and Practice. I'll be there, so if you are able to go, please look me up.

Forensics: New technique recovers fingerprints from bullet casings after firing

Forensic scientists at the University of Leicester (UK) and Northamptonshire Police (UK) have announced a way to recover fingerprints from fired shell casings. The technique involves the use of an electric charge to attract an electrically conductive powder to the minute amount of corrosion caused by handling the shell casing. The act of firing the bullet actually improves the ability of the technique to recover the print. For more information, see this article from Science Daily.

PS. On re-reading my post, I noticed that I did not supply any answer to the obvious question of "so what?". The reason this technique is particularly interesting is that it potentially provides additional forensic evidence that could identify participants in gun crimes. Imagine being able to re-open a "cold case", for instance a drive-by shooting, using nothing more than a spent shell casing (and a fingerprint database, of course). Hopefully, there will not be any hidden "gotchas" in the details and this technique will be able to fulfill its initial promise.

Image Forensics: More on tamper detection

Steve Eddins (Mathworks Inc., USA), writing on his company-sponsored blog on image processing, has an excellent post regarding an article by Professor Henry Farid in the June 2008 edition of Scientific American (USA, center-left, scientific magazine). The article is primarily about tamper detection or, in other words, spotting retouching or "photoshopping" of photographs.