Image Restoration: iMovie Stabilization feature

Despite the best of intentions, I have not yet been able to get around to testing Apple's new iMovie video stabilization feature for the Mac OS (Operating System). I will, however, whet you appetite with a Macworld review I've come across that gives examples.

Enjoy!

Physics: A round-up of recent interesting links!

My aplogies for my light posting of late. Outside commitments have kept me from posting nearly as much as I would like. Here is a collection of links that I have saved up over the last several weeks to blog about. I hope you enjoy them, but please note that some of these are not serious, scientific articles - just because it can be found on the Internet doesn't make it science, much less forensic science! If you are particularly interested in any of the topics addressed below, just let me know and I'll delve further in a future posting.

K-Lite codec package update

X-rays made from Scotch(R) tape (hat tip to A.A.)

Superconductivity Can Induce Magnetism

Deaf people feel their way to speech

Seeing Through The Skin: Optic-less Imaging Technology Could Beat Lens-based Imaging Devices

HOWTO read the secret forensic dots in your laser-printer output

Biometric identifcation by body language

Sound-card oscilloscope

Audio bone headphones

Scientists Watch As Listener's Brain Predicts Speaker's Words

Hidden airport scanner will pinpoint terrorists

Overpaid professions

Military camouflage

Police probe cell phones to catch criminals

How magicians control your mind

How forensic lab techniques work

Computers reassemble pieces of fractured archaeology

Review of Microsoft's Photosynth

Images of atmospheric optics

12 worst Photoshop mistakes ever

Darpa super-resolution vision technology R&D

How other senses adjust to blindness

Family name geographical profiler

Image Recognition: Military requirements push technology forward

The Strategy Page has an article about how the proliferation of video on the battlefield (e.g. from surveillance cameras and even night vision goggles) is driving technology development. Initially, it was the UK (United Kingdom) that drove image recognition technology with its massive deployment of CCTV in public spaces (e.g. train stations, airports, city centers, and shopping malls). Now, it is the military.

The benefit from computer-assistance in analyzing video comes from the following:

1. Volume (i.e. the sheer number of cameras and, hence, images to be monitored and/or analyzed)
2. Concentration (i.e. the human visual system loses the ability to concentrate effectively on images after about 20 minutes of continuous viewing)
3. Memory (i.e. computers can track and, possibly, predict more things simultaneously than a human can because, generally speaking, computers are not nearly as attention and working-memory limited in the short-term as humans and far outstrip us in their ability to recall video sequences over the long term - they can just play back the video recording off of their hard disks)
   

The article claims that the abilities of computer systems to recognize patterns is rapidly improving and approaching that of humans - that is no small feat as humans are simply amazing in their ability to perform real-time pattern analysis.

One intriguing point made in the article is that the current conflicts are generating a lot of real-world recordings of "bad behavior" that can be used to train and test new pattern analysis and prediction algorithms - training data like this is like gold to us signal processing types!

Enjoy!

Image Forensics: Adobe launches CS4

Adobe has launched the latest version of its Creative Suite, which includes, most importantly for image/video forensic types, Photoshop. Headline features of Photoshop CS4 include:

• GPU-based drawing of documents onscreen (for speed improvements)
  
• 64-bit for Windows (but not for Mac OS-X, at least yet)
  
• Expanded 3-D paint, lighting and rendering tools

Hat tip: Ars Technica

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.

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.

Image Forensics: How to spot photo retouching

Slate (US, center-left online magazine) has an article (Were the Dove ads retouched? How to spot Photoshop chicanery) on some of the techniques used in identifying if a image has been retouched. In a forensic examination of evidence, this procedure is known as tamper detection. It should be noted that the author, Jacob Leibenluft, reached out to several experts while researching the topic, including George Reis of Imaging Forensics.

Enjoy!

Optics: "Look Mom, no lens!"

Similar to a child demonstrating how he can ride a bicycle without using his hands, now we have scientists taking pictures without a lens.

Upon reflection, it was a predictable next step. First we had the major advance of refocusing out-of-focus images by, in essence, building a correction lens, all in software. This is what allowed NASA (the USA space agency) to correct some of the Hubble Space Telescope images after it was put into orbit with an out-of-focus optical chain.

But it one can simulate a lens well enough to correct an image, even if imperfectly, why not replace the real lens with a simulated one and focus the unfocused image received by the (lens-less) sensor? That is what the team at Argonne National Laboratory (Illinois, USA) is working on. Of course, simulations are rarely, if ever, as good as the real thing in all aspects, but if for their particular problem (X-ray imaging) the simulated lens is better than their real one, then they will have improved the imaging system and advanced the state of the art yet again.

Forensics: Name that codec in one note

Sometimes I feel that I lose track of the founding purpose of this blog - which is to educate people in a non-commercial way about audio and video forensics. In that spirit, I will let the non-specialists among you in on a current trick of the trade - namely, G-Spot. G-Spot is often the first thing a video forensics professional turns to when a piece of digital surveillance video evidence won't play on the laboratory's workstation.

G-Spot is a software application developed by Steve Greengerg to identify what codec is needed to play a video file. Given the plethora of low-cost digital video recorder (DVR) security systems on the market, many, if not most, with their own proprietary codecs, G-Spot can be a life saver. Here is a link to a review of the application (Note: there is some sexual innuendo, but I did not find it to be overly crude).

Now you know what drives many video examiners to distraction every day and what they turn to for the answer.

Computer Audio and Video: Codec packs

Being able to play audio and video files, often years after they were originally created, has been a steadily growing problem for audio, video, and computer forensic examiners.

Of course, video examiners encounter this almost daily if they are dealing with security digital video recorder (DVR) files because of the proprietary codecs (which is short for COder DECoder, and is the software program that converts video to and from a particular digital file format) used by manufacturers of the systems to lock users into their brands.

Even for those who do not process security DVR every day, things have been getting worse. Part of this is due to changes in the latest Windows Media Player where Microsoft removed one of the popular codecs previously used to encode/decode AVI files. Many people are under the impression that AVI is uncompressed and either doesn't need a codec or only has one universal codec. This is far from the truth. AVI, like WAV, is a very flexible format and it supports the use of almost any audio or video codec. To play the file, you have to have the correct codec - period. No codec, no playback - it is that simple.

I was faced with this problem just recently due to the Microsoft changes. The files were uncompressed AVI and would not play on three different machines, even though they played back correctly only two months before. A bit of digging found the cause. The solution ended up being to download an audio/video codec pack. I used the free one found here, but there are others out on the Internet also.

You can imagine how this can be a problem for law enforcement where evidence may need to be archived for up to 25 years and still be able to played back. All it takes is one automatic update and the ability to playback can cease. This is why I recommend to my students that they always include a copy of a freeware player that will play back the media as part of the archived evidence.

Computer Audio & Video: Windows Vista changes how audio and video are handled

Howstuffworks has the best summary of Windows Vista as related to audio and video rendering that I've read thus far. The highlights are:

• The graphics and audio drivers will run in user mode instead of kernal mode so that errors with either will not cause 'Blue Screens of Death.'
• Vista supports DirectX 9 but is really built around DirectX 10.
• DirectX previously did not require graphics hardware to support many DirectX capabilities; now, however, only three features are optional.
• Finally, the sound volume coming from each application can be separately controlled.

There is even more interesting information about Vista in the article for those who are interested.