Monday, April 30, 2007

Audio: Combination noise isolating earbud and in-ear microphone

The Raw Feed has a description and picture of a new cell phone earbud with built-in microphone by Japan's Nap Enterprise Co. They claim 30 dB noise reduction (passive, not active like noise-canceling earbuds and headphones). Because the microphone pickup is in the ear canal and isolated from the outside world by the wearer's head and the earbud itself, the speech picked up by the microphone should be much, much quieter. I look forward to hearing an audio sample! If anyone comes across one, please point me to it.

Admin: New layout completed

It is done (finally). Enjoy!

Admin: New layout to blog

I am in the middle of upgrading to Blogger's new Layouts feature so that I can add widgets to the blog. Please bear with me. The customizations I've made (such as the links list) have all been cleared away and will take some time to add back in. Regardless, the blog is functional and new posts and comments are still going up.

One widget that I've already added is the one for subscribing to feeds (found at the top right). It is also now easier to browse the archives (found at the lower right).

Kind Regards,

Sunday, April 29, 2007

Evidence: New procedure to improve accuracy of witness recollections

BBC Focus Magazine has an article about a technique, called self-administered interview (SAI), that is said to improve the accuracy of witness recall by 42 percent.

Under current UK police procedure, there is apparently a two step process for interviewing a witness - first a brief (summary) interview and then a more detailed one. The proposed procedure instead makes the initial process much more intensive and has the witness record as many details as possible using a questionnaire. The work is by Dr Lorraine Hope (University of Portsmouth, UK) and other researchers at University of Abertay and Florida International University.

In contrast to what the current common perception of what crime scene investigation can accomplish is, in reality there are a large number of crimes where the crucial evidence is testimony by an eye, or ear, witness. This makes accurate recollection extremely important, particularly since detailed memory does degrade rapidly with time in most people and eye/ear witness testimony, as currently "managed", is at least occasionally later found to be erroneous.

Additional Link: The Daily Telegraph (UK, center-right newspaper) also has a write-up with a few more details.

Computer Audio: Audition 3 in the works and an audio forensics wish list

First it was a rumor and now it is confirmed - Adobe Audition 3 is in development and Adobe plans to announce more about it later this year. A search of their web site didn't yield any additional details but there is a post on Hart Shafer's blog (Hart's Audition) that confirms it and mentions that it is on a different schedule than the rest of their Creative Suite. Hart Shafer is the product manager for Adobe's studio products, which includes Audition.

Admittedly, audio forensics is a small, niche market away from their core customer base, but if we are lucky, our needs will overlap the needs of their studio customers and a fine product will become even more useful to us. From a forensics point of view, here are the things that I have on my wish list:
  • Improve support for working with multi-channel WAV files that are not intended for surround sound, including easy trimming of multiple channels and saving, for starters.
  • Speed up loading of large multi-channel files
  • Improve the spectrogram interface to allow easy and accurate display and analysis of specific frequencies.
  • Include an option to decrease the streamlining (in other words, an "option to allow more options")
If you have anything to add to the list, just email me (link found on right side, near the top - don't forget to remove the anti-spam text!) or post a comment.

Wednesday, April 25, 2007

Bird songs and urban noise

You may have seen the fascinating nature videos of wild birds mimicking various man-made noises like cell/mobile phone ring tones, chainsaws, and the like. Now comes a study into another way that birds have adapted to living around mankind - singing at night to be heard further since it is quieter. A news article can be found here.

Sunday, April 22, 2007

Security: The weakest link

Q.- What high tech hacker tools are needed to steal $25 million of diamonds from behind all the layers of a bank's security system?

A. - Chocolates and charm.

The hacker community calls this "social engineering."

Biometrics: Gait recognition accuracy rates in controlled conditions

Researchers at the University of Southampton (UK) reported a 100% accuracy rate for verifying the identity of individuals by automatically analyzing the way they walk. IT Week (a UK information technology magazine) has some details.

Based on the IT Week article, it appeared to me that all the tests were conducted under controlled conditions. Visually-based biometric techniques generally require good lighting conditions (i.e. proper exposure of the image) and resolution. They also require that the features needed for recognition are not occluded.

Why would one need gait recognition when face recognition already exists? Some obvious advantages are that gait recognition doesn't require that the face is oriented toward the camera and the image resolution requirements are not as high. But if the conditions are controlled anyway, why can't the person be required to be close to and facing the camera?

A couple of questions that come to mind are 1) how much less the spatial resolution can be and 2) how robust it is to image compression (e.g. MPEG-4)? These could give the technique additional advantages.

One final observation I should make is that, as with all biometric techniques, being able to fuse the results of more than one technique improves the system accuracy and robustness. That alone could justify the inclusion of the technique in fielded systems.

Back to blogging

I would not recommend the particular Toshiba Satellite notebook that I have - two major warranty repairs in nine months, one to replace a bad display and a motherboard replacement. I do have many good things to say about the repair shop that I used for the motherboard replacement (Topaz Support). I am keen on them not just out of relief to have my notebook back, but because they were all the things that the last shop wasn't - helpful, efficient, communicative (they called me to give me status updates, not the other way around), and professional.

On the technical side, I was surprised to find that it seemed to work significantly faster than before. I haven't investigated why, but I wonder if it is because they updated the BIOS to the most recent version.

Monday, April 09, 2007

Admin: Cause and Effect

Cause - a dead computer (no signs of life at all...)

Effect - limited posting.

This particular computer (a Toshiba Satellite) is now on its second warranty repair in the nine months since I bought it. I hope to be back blogging soon.

Kind Regards,