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Welcome to the Forensic Multimedia Analysis blog (formerly the Forensic Photoshop blog). With the latest developments in the analysis of m...

Monday, December 31, 2012

Happy New Year

From all of us, to all of you ... a happy and prosperous new year. Thank you for your continued support.

Wednesday, December 19, 2012

AmpedFive adds Color Deconvolution

Remember this article? Color deconvolution is an awesome tool for complex background removal that has applications across a number of forensic disciplines. Now, it's part of Amped FIVE. How cool is that?!

If you haven't checked out Amped FIVE, you owe it to yourself to spend a few moments to see just how robust this tool is. Latent Prints, Questioned Documents, Footwear, Tool Marks, Photogrammetry in 2d or 3d, Video, Images ... you name it. All for a very reasonable price. Well worth the investment.

Friday, December 14, 2012

The Perils of Using the Local Computer Shop for Computer Forensics

Along the lines of when is an expert not an expert, Larry Daniel posts the following quote in his article about using an unqualified person to perform computer forensics,

"Hickory Brands hired a service provider called Computer Ants, whose owner and operator, Thomas Scott, testified to never having performed forensic services in the context of a lawsuit. Scott, who the defendants tasked with producing documents responsive to search terms from a total of 308 million potentially relevant files on 35 computers and six servers, had previously worked as a truck driver and a security manager for Bass Pro Shop."

"The result was the delivery of 1,700 sensitive documents to the opposing counsel that resulted in a heated clawback motion, in which the judge found that the attorneys did not take the "reasonable steps" required by law to prevent the disclosure."

You can read more about that case by clicking here.

Tuesday, December 11, 2012

New Exclusive Photoshop Features for Creative Cloud Members

For a closer look at what’s new in Photoshop CS6 (13.1), click here.

Some of the improvements that may interest you are:

Retina Display Support
See more of the details in your images and in the Photoshop user interface when viewing on new Retina displays available on MacBook Pro.

Workflow improvements
Discover new user-inspired timesavers including Crop tool refinements, better naming of merged layers, the ability to quickly move a path anchor point using the spacebar and the option to see up to 100 items in your list of recently opened files. Easily create large images for signage, panoramas, and other large outputs by saving JPEGs of up to 65,000×65,000 pixels, more than twice the size previously supported. Ensure consistent type formatting across multiple documents by defining global styles, which are then available in any Photoshop document.

Conditional Actions
Speed up image processing by creating Conditional Actions. These commands use logic to automatically choose between different Actions based on rules that you establish.

Note: With the exception of Retina display support, the new features listed above will only be available to Adobe Creative Cloud members. For government and non-CC members, it just got interesting.

Monday, December 10, 2012

The costs of government

I try to keep up with current events. I read an article on Bloomberg.com about government employee costs under the title, "$822,000 Worker Shows California Leads U.S. Pay Giveaway." Being a part time government employee, I'd like to offer a bit of a rebuttal.

Point 1: "Today, the state’s highest-paid employees make far more than comparable workers elsewhere in almost all job and wage categories, from public safety to health care, base pay to overtime." - This interesting page makes the point that police detectives make more than private detectives on average and by region. What's lost on both pages is the fact that private sector workers can work as much as they are able, take on additional work, work for whomever they like, and negotiate for all of those conditions individually. Speaking of my own situation, I don't set my wage or working hours (no matter how hard I work, or how much I innovate, I get the same rate as everyone else in my pay grade). I don't have a say in benefits (including retirement). I can't actually opt out of my benefits package. I have to pay the union for the privilege of bargaining against my interests. I can't have a second job unless the city gives me permission. I don't get money for overtime worked - I get time off (which has to be used before vacation time). I don't get to go home until I'm relieved, which can be days beyond when I'd like to go home. Thus, there really is no comparison to a police detective and a private detective. The only real thing that we have in common is that we can both quit, and walk away (though my costs would be substantially higher).

Point 2: "From coast to coast, states are cutting funding for schools, public safety and the poor as they struggle with fallout left by politicians who made pay-and-pension promises that taxpayers couldn’t afford." - In California, the state is controlled by a supermajority of Democrats. Democrats and organized labor have walked hand-in-hand for generations. It's borderline conflict of interest to have the two negotiating over wages and benefits. Yet, there's more to the story. California is a magnet for those seeking opportunity. There's one side, those wishing to start a business and grow wealthy. Then there are those who come from all over seeking to avail themselves of our rather generous social programs. California, with 12% of the U.S. population, has one-third of the nation's welfare recipients. This influx of people requiring state services comes at a cost. Which would you rather pay for, schools, police, libraries, parks? All of the above? As each constituency fights for its piece of the pie, there will be winners and losers. Right now, the losers are the tax payers - who after Jan 1 will be some of the most burdened in the country.

Point 3: "“All it took was for political leaders to think more about the general population and the future, rather than their political futures,” said Crane, a Democrat who worked as an economic adviser to former Governor Arnold Schwarzenegger, a Republican. “Citizens should be mad as hell, and they shouldn’t take it anymore.” - Citizens aren't mad as hell. They voted in a Democrat supermajority - see point 2. The results of my own state assembly district is still up in the air. As it stands, the democrat challenger is ahead by 145 votes. With one party rule - they can do whatever they like (for good or ill). We'll see where the democrats lead the state.

Point 4: "Last year, Brown waived a cap on accrued leave for prison guards while granting them additional paid days off. California’s liability for the unused leave of its state workers has more than doubled in eight years, to $3.9 billion in 2011, from $1.4 billion in 2003, according to the state’s annual financial reports." - Why did the governor need to uncap accrued leave? How many prison inmates are in California's prisons? Is the trend rising or falling? Why? Inmates need to be housed and guarded 24 hours per day. They need food, laundry, medical care, and etc. Has the corrections realignment helped or hurt the overall situation? Is passing the buck to the counties a solution, or does it just postpone the problem?

Point 5: Elections have consequences. Here's the 2012 Platform of the political party that controls California. Every item has an actual cost today, plus a compounded (future) cost. Our education system "was once the envy of America. Our K-12 schools were among the best funded in the country and under the leadership of Governor Pat Brown, the California Master Plan for Higher Education made our community colleges, our California State Universities and our University of California institutional systems to emulate throughout the world. In recent years, our continual disinvestment from education threatens our ability to offer our youth the education they require to usher our state into the future." This statement from our leaders flies in the face of our state's constitution - which requires that a minimum of 40% of the state's general fund be spent on education. The actual number is closer to 50%. Thus, 50% of the world's 7th largest economy is spent on education ... and our kids are suffering? Where's the money going?

Here is the platform of a party that holds no current influence in Sacramento. Again, each of the items contained in the Libertarian Party's platform has a cost, as well as a savings for those areas that they think government should no longer control. Items 1 and 7 would reduce the prison population by about 40%. Item 10 is a huge cost saver - but now out of line with Obamacare. Item 18 gets rid of the state's ABC system. And so on ...

Thus, elections have consequences. California's voters chose to have a supermajority of leaders who believe in a large, all encompassing government. That choice has a high cost. If the voters really were mad, then the 2014 elections should see the Libertarian Party sweep into office ... and a massive redistribution of responsibilities back to the individual.

John Overton was right.

Thus endeth the rant.

Tuesday, December 4, 2012

Single View Metrology

Criminisi, et all, in their work Single View Metrology, describe how 3D affine measurements may be computed from a single perspective view of a scene given only minimal geometric information determined from the image. This minimal information is typically the vanishing line of a reference plane, and a vanishing point for a direction not parallel to the plane. Their work shows that affine scene structure may then be determined from the image, without knowledge of the camera’s internal calibration (e.g. focal length), nor of the explicit relation between camera and world (pose).

In particular, they show how to (i) compute the distance between planes parallel to the reference plane (up to a common scale factor); (ii) compute area and length ratios on any plane parallel to the reference plane; (iii) determine the camera’s (viewer’s) location. Simple geometric derivations are given for these results. They also develop an algebraic representation which unifies the three types of measurement and, amongst other advantages, permits a first order error propagation analysis to be performed, associating an uncertainty with each measurement.

They demonstrate the technique for a variety of applications, including height measurements in forensic images and 3D graphical modelling from single images.

Building on this foundation, the Measure 3d tool in Amped FIVE computes real-world distances directly on the image. The Measure 3d Single View Metrology implementation is based on the fact that some image lines, which are parallel in the real-world, join in a point in the image, named the vanishing point, due to the perspective. The vanishing points themselves are obtained by identifying, thanks to the geometric information (two or more lines for each x/y/z direction) provided by the user, sets of 3D points (x,y,z) that belong to the segment lines for each direction of interest. The scene perspective can be reconstructed from vanishing points: transforming the geometric information into a system of linear constraints on the coordinates of the 3D points and using the 2D observations (the known distance) to further constrain the 3D points. As result, 3D measurements may be computed from a single perspective view of a scene given only this minimal geometric information determined from the image.

The validity of the Single View Metrology approach is assessed by the Monte Carlo statistical tests: it determines how the uncertainty propagates from input to output of the computation chain and estimate the measurement accuracy.

But, as powerful as Amped FIVE is, it's only as good as the inputs received from a trained analyst. One of the examples used in my training sessions is a video from a convenience store. I have been to the scene and measured the floor tiles as 12" square. There is a discernible checker board pattern to the tiles, so it's easy to get X and Y segments from an 8' x 8' block of tiles. The store has two entrance/exit doors with security measuring tape affixed to the door frames, giving us the Z. Once this information is put into FIVE, measurements can be taken from within the scene with a high degree of reliability.

The biggest difference between SVM based photogrammetry, and methods like reverse projection photogrammetry, or products like iWitness, is that isn't the need to re-shoot the scene. Measurements are taken of the area that was captured by the video already in hand, like the floor tiles and the door frame - things that don't generally change. These measurements are then used for your calculations, lowering costs and time to completion / results.

Thus, if your are interested in adding Photogrammetry to your offerings, you should consider adding Amped FIVE to your tool kit.

Monday, December 3, 2012

Measuring within images

Here's a question - is it possible to measure within images? The answer, of course, is yes (with a gigantic caveat). It depends on what you mean by measure, and what it is that you'd like to measure.

In Amped Five, you have the ability to measure in 1d, 2d, and 3d. Tomorrow, we'll look at 3d measurements. Here's a look at 2 dimensional (X,Y) measurements within images.

The Amped FIVE Measure 2d tool computes a specific measurement distance in a rectified image. Image rectification corrects image distortion by transforming the image into a standard coordinate system (think perspective correction). Given an image of a planar surface (2d), points on the image plane can be mapped into corresponding points in the rectified plane by means of a projective transformation called homography. Points in one plane are mapped into the corresponding points in the other plane as follows:
X = Hx where x is an image point, X is the corresponding point on the world plane and H is the 3x3 matrix representing the homography transformation. Once the homography matrix H is known (or has been computed), any image point can be mapped into the corresponding location on the rectified planar surface and distances between actual points can be extracted by computing the Euclidean distance d(X1,X2), where X1 and X2 are the actual points of the two points x1 and x2 on the image plane. The homography is computed directly from a set of at least four points by the Perspective Correction filter.

Correct Perspective, in FIVE, maps a desired quadrangular region to a rectangular one, which allows seeing the plane of interest as the plane of the image was parallel to it. Pixel values are interpolated with a bicubic algorithm. (Anil. K. Jain, Fundamentals of Digital Image Processing, Prentice Hall, pp. 320-322, 1989.)

So what's the takeaway here? Measuring planar surfaces, or making two dimensional measurements within images, requires that a perspective correction process be applied first. If this isn't possible, then you should consider 3d measurements - which will be covered tomorrow - that deal with perspective as it is, and factors/computes the vanishing point in the image.

Thursday, November 29, 2012

Jobs in forensics

As a few readers already know, I'm a PhD candidate working on a problem in the forensic sciences that I've illustrated here from time to time. A few years ago, the National Academy of Sciences declared the state of police (law enforcement staffed) forensic sciences to be quite dismal. Essentially, cops with nothing more than a driver's license and some vendor training on their tools were calling themselves forensic scientists - and coming to some troubling conclusions along the way.

Senator Leahy came along later can wrote a bill that put the NAS report into legislation - declaring that folks should have at least a masters degree to practice forensic science. The problem: no schools confer degrees for many of the CSI type tasks - latent prints, multimedia (video/image/audio), cell phones, tool marks, fire arms, and etc.

Along comes the Obama DOJ to say, it's sad that Leahy got no sponsors to his bill, but we like the idea. We'll do it within the construct of the DOJ's funding priorities - in other words, if you want federal money or you want to bring evidence in federal court, then you'll need to do X, Y, and Z (the work was done in the Executive Office - Subcommittee on Forensic Sciences).

So, schools are being created to confer this type of education. My area in this in multimedia. Part of my PhD dissertation deliverable is the creation of a school of media forensics - a school in a box deliverable that can be given to colleges in any city to start their own programs. In that way, local practitioners do not have to move away from their local areas to UC Denver in order to pursue the degree that they will now need.

Here's the dilemma. Some of the best candidates for this type of work moving forward (forensics) are autistic people. They may fall under one or many of the diagnosis given to autistics - high functioning autism, Aspergers Disorder, Sensory Processing Disorder, PDD-NOS, and so on. But an initial survey has found that there are many people involved in this industry are either non-diagnosed or diagnosed on the autism spectrum (high functioning side). But while their brains are perfectly wired for forensics - the other characteristics of the autism spectrum cause a problem for entering LE.

Many LE agencies polygraph applicants - not only sworn staff, but all staff - or staff who will handing sensitive cases like anti-terror, narcotics, vice, or internal affairs. Thus, many of the potential forensic scientists will face a polygraph exam.

If you believe the marketing on the polygraph - that the instrument measures the biorhythms, these are not going to read the same for autistics as in a neuro-typical subject. To put it another way, taking the polygraph industry at their word that the instrument shows the readings and the examiner interprets the results - how will the examiner interpret the results of an non neuro-typical person?

Here's some examples:
• One of the characteristics of Aspergers is no eye contact. Another is flapping, or the inability to sit still or some other wild body movement - like a fidget.
• Autistic people may be claustrophobic in terms of things touching them. How will their body react to the blood pressure cuff? How will their body react to the neumo tubes? Sitting still, strapped to a chair generally doesn't work for autistic people.
• Autistic people generally do not like bright lights, flickering fluorescents, or loud sounds. Sitting still, strapped to a chair in a room with bright fluorescent lighting?

Hopefully, you can see where this is going. Many of our best candidates will fail a polygraph exam simply because it is not geared to accommodate the characteristics of autistic people. In failing the exam, they will necessarily be excluded from on the industries uniquely suited to their strengths.

I am hoping to interview both polygraph professionals and other experts in the field on a series of questions related to the premise, how do you effectively polygraph an autistic person.

All interview subjects will be treated with dignity and respect. Results will be kept confidential. Data will be used to support my research and no names will be used. Please feel free to direct message me if you are interested. Also feel free to respond with additional questions or requests for clarification.

Thank you.

Wednesday, November 28, 2012

Does overt or covert depend on the time of day?

This Lancaster (PA) case illustrates a few points about using CCTV evidence in trial.

Cameras mounted outside of a business were used in recording some activity that the prosecutor wants to use in trial. The essence of the defense's objection is that the defendant couldn't see the cameras - it was 1am and quite dark. Thus, with the lack of lighting, does overt placement become covert? Hmm.

Additionally, the CCTV system had an active microphone that recorded the defendant's conversation in the public space, which may be a crime in itself.

Lots of issues at play in this murder trial.

Monday, November 26, 2012

Courts Divided Over Searches of Cellphones

This just in from the LA Times: "Judges and lawmakers across the country are wrangling over whether and when law enforcement authorities can peer into suspects’ cellphones, and the cornucopia of evidence they provide.

A Rhode Island judge threw out cellphone evidence that led to a man being charged with the murder of a 6-year-old boy, saying the police needed a search warrant. A court in Washington compared text messages to voice mail messages that can be overheard by anyone in a room and are therefore not protected by state privacy laws.

In Louisiana, a federal appeals court is weighing whether location records stored in smartphones deserve privacy protection, or whether they are “business records” that belong to the phone companies.

“The courts are all over the place,” said Hanni Fakhoury, a criminal lawyer with the Electronic Frontier Foundation, a San Francisco-based civil liberties group. “They can’t even agree if there’s a reasonable expectation of privacy in text messages that would trigger Fourth Amendment protection.”

Click here to continue reading the story.


Wednesday, November 21, 2012

Colleges - the future site of forensic labs?

I've been thinking about this topic ever since the NAS report was issued, can forensic labs function well under police supervision? This article from India hints at our future here in the US - given budget shortfalls, staff cutbacks, and crime rates - can police departments keep up with forensics?

Sure, DNA is the sexy CSI science. But what about latent prints, crime scene photography, or multi-media forensics? As budgets shrink, governments can't afford to back fill open spots in their technical labs. The result, evidence isn't processed.

I've been saying that I think the solution is regional forensic labs at college campuses. Having the "official" lab at a college satisfies a number of issues raised in the NAS report, as well as by Senator Leahy. I think that this model solves a number of problems - more cops out of the labs and back on the street, disinterested third parties practicing forensic science, getting the CSI stuff away from fluctuating city budgets and under a federal funding scheme, and etc.

Just something to think about for now. But, something's got to give ...

Tuesday, November 20, 2012

Facial recognition in the news

This just in from RT: "In a single second, law enforcement agents can match a suspect against millions upon millions of profiles in vast detailed databases stored on the cloud. It’s all done using facial recognition, and in Southern California it’s already occurring.

Imagine the police taking a picture: any picture of a person, anywhere, and matching it on the spot in less than a second to a personalized profile, scanning millions upon millions of entries from within vast, intricate databases stored on the cloud.
It’s done with state of the art facial recognition technology, and in Southern California it’s already happening."


"Up to 4 million comparisons per second, per clustered server” — that’s how many matches a single computer wired to the FaceFirst system can consider in a single breath as images captured by cameras, cell phones and surveillance devices from as far as 100 feet away are fed into algorithms designed to pick out terrorists and persons of interest. In a single setting, an unlimited amount of cameras can record the movements of a crowd at 30-frames-per-second, pick out each and every face and then feed it into an equation that, ideally, finds the bad guys.

"I realized that with the right technology, we could have saved lives,” Joseph Rosenkrantz, president and CEO of FaceFirst, tells the Los Angeles Times. He says he dreamed up the project after the attacks of September 11, 2001 and has since invested years into perfecting it. Not yet mastered, however, is how to make sure innocent bystanders and anyone who wishes to stay anonymous is left alone as he expands an Orwellian infrastructure that allows anyone with the right credentials to comb through a crowd and learn facts and figures of any individual within the scope of a surveillance cam.

Speaking to reporters with Find Biometrics in August, Rosenkrantz said that the system is already in place in Panama, where computers there process nearly 20 million comparisons per second “using a FaceFirst matching cluster with a large number of live surveillance cameras on a scale beyond any other system ever implemented.”

Read the whole story by clicking here.

Monday, November 19, 2012

Allegations of sloppy work, bias, dishonesty dog Oregon State Police handwriting unit

This just in from the Oregonian: "An Oregon State Police handwriting examiner committed a serious error in a killer-for-hire case last January, provoking so much finger-pointing that the future of the agency's document analysis unit is uncertain.

State police officials, confronted by a whodunit under their own roof, suspended all work by the handwriting unit in March, saying little about why. But internal reviews obtained by The Oregonian through open-records filings detail allegations of bias, sloppy work and dishonesty.

Out-of-state experts are now re-examining 35 criminal cases worked by the unit's two handwriting analysts, partly to ensure that no innocent people were convicted on faulty findings. Washington State Patrol officials, who relied on the examiner who made the error to review at least 40 of their cases from 2009 to 2010, are waiting to see what the experts find."


"Kelley and Emmons say they have no problems with their work being reviewed by outside experts, and both say no mistakes will be found.

But their suspension has caused another problem.

The accreditation board of the American Society of Crime Laboratory Directors declined to accredit the handwriting unit as a result, leaving state police with no way to conduct handwriting examinations on their own.

They have had to farm out the work to the FBI and other agencies."

Read the whole article by clicking here.

Friday, November 16, 2012

Elections have consequences

I'm often asked about my political leanings. Given my profession, people make assumptions as to my party affiliation. They're often wrong.

Folks have been asking for my take on where the world is heading, and so forth, given the fact that the US has just had a big election. So, here's my analysis of the US's election results, and sundry associated issues:

Progressives have spent a century or more creating a demand for their products and services. Obama, for his part, handled the supply side of the equation. Folks like to see results, a bridge or library built, a program to help, etc. Robert Byrd is an excellent example of this re-election strategy. You can't go anywhere in WV without seeing his name plastered on some official sign. Republicans, for their part, have not offered an alternative set of products and services over the corresponding time period. The message of cut this, but not that, doesn't ring true for over half the country.
The conservative message of save for tomorrow rings hollow when the government drives down interest rates such that your savings are eaten away by inflation. Thus, people spend what they have and hope for a better tomorrow ($1000 in a savings account does you no good when you neighbor's flat screen is bigger than yours, after all).

The conservative message of investment and the power of compound interest is undercut by the government's insertion of itself into the market. It picks winners and losers, it deems companies too big to fail, it plays with the value of money and commodities. Given this, would you trust the stock mar
ket? Would you trust your retirement to the stock market?

The conservative message of family values continues to be undermined by politicians who say one thing in public, pass judgement on others through legislation, then do entirely different things behind their own closed doors. Pro-marriage legislators turn out to be cheating on their spouses. Anti-gay rights legislators turn out to be gay. Why can't well ordered liberty include all of God's creation? Why can't pro-freedom, pro-choice, and pro-American mean the same thing?

A few years ago, I wrote a book on what I thought were the essential qualities of a leader. Modern Freemasonry takes a good man, and illustrates the path to a well lived life. Thus, it's little mystery to me why so many of the world's heroes are/have been Freemasons.

Everyone makes mistakes - did you own them? Did you learn from them? DId you ask for forgiveness? What to be a leader - whom have you followed? Can a man lead who does not know how to obey? Do you have unhealthy attachments? Is your life out of balance? Can you make and keep commitments? Do you know how to be a friend? In whom do you put your trust?

So, lift your head up high. It's not the end of the world. Your family needs your full efforts, as does your neighborhood, town, county, state, and your country. Remember that your work recommends you, as does the company that you keep. Remember that your legacy includes not just those fixed assets that you leave behind, but also the memory of you that remains in your children and all of those of whom you've impacted over the years.

So, chin up, mates. It'll be fine. We'll make it through these tough times, together.

Thursday, November 15, 2012

History log function now in Amped FIVE

Yesterday, Amped Software announced a new update to FIVE. Along with some bug fixes, FIVE now has an automatic logging feature. You'll find this by clicking on View>Open Log Folder.

Since the new default is to log every action in FIVE, I just wanted to remind you of a post I wrote a few years ago about the discovery issue related to history logs.

... Smith and Bace make clear the fact that the reports we generate will provide fodder for cross examination. This includes the History Log. If your log is not handled correctly, it will likely include a running list of every image ever processed by you on your computer. Do you want to turn this list over for discovery? Imagine the questions it would generate. If your Log only shows work on a few images, but hundreds were turned in for discovery, you should expect a long series of questions ...

As the FIVE history logs record not only the actions, including play and pause, but also the local time, file locations, and etc ... you might want to run the use of this feature past your chain of command and your risk management section. In the mean time, you can turn this feature off in the Program Options window, if you want to.


Wednesday, November 14, 2012

A Texas Prosecutor Faces Justice

This just in from the New York Times: "In just about a month from now, Texas will witness a rare event: a former prosecutor is going to be held to account for alleged prosecutorial misconduct."

"What makes the Morton case unusual is that, thanks to the Innocence Project’s re-investigation, Ken Anderson will soon go before a Texas Court of Inquiry. If the court believes that Anderson’s alleged misconduct rises to the level of a crime, it could refer the matter to a grand jury. But the Court of Inquiry exists only in Texas, and is almost never used even there.

In truth, Anderson isn’t the only Williamson County prosecutor who faced consequences as a result of the Morton case. His successor, John Bradley, was the one who had fought for years against the DNA testing of the bandana. Seven months after Morton was set free, Bradley, who had always been a shoo-in for re-election as district attorney, was resoundingly defeated.

When I spoke to him the other day, he told me that he now believes he had been wrong to fight so hard against the DNA testing. “We shouldn’t set up barriers to the introduction of new evidence,” he said. Although it would mean more work for prosecutors, Bradley now believes that examining important new evidence is “a legitimate and acceptable cost to doing business in the criminal justice system.”

Bradley will leave office soon. He told me he was going to start a law practice specializing in appellate work. Here’s hoping he argues some appeals for the wrongly imprisoned."

Click here to read the whole story.

Tuesday, November 13, 2012

virtual reality crime scene training available to state and local law enforcement

This just in from Officer.com: "The nonprofit National Forensic Science Technology Center (NFSTC), in partnership with the University of Tennessee (UT) Law Enforcement Innovation Center (LEIC), is making virtual reality crime scene training available to state and local law enforcement professionals for the first time. For active law enforcement officers who register in 2012, the Investigator-Virtual Reality (I-VR) training is free of charge and funded by the National Institute of Justice.

Brian Cochran, a detective for 11 years, is a graduate of UT’s National Forensic Academy and was among those who helped develop the training. “Overall, the training is meant to be introductory,” says Cochran, who works in the crime scene unit of the Boone County Sheriff’s Office in Kentucky. “It [covers] general things: scene security, searching for evidence, and properly packaging, documenting and photographing evidence—the fundamentals of crime scene management and processing.”

Entry-level law enforcement personnel who may want to become crime scene investigators or forensic practitioners can benefit from I-VR. The training can also be used as a refresher for seasoned investigators, says Emily Miller, a specialist with LEIC at UT’s Institute for Public Service.

From January to the end of September, more than 400 participants registered for the course, Miller says. She says participants have included law enforcement officers, first responders, crime scene investigators, field training officers, rookies and veterans."

Click here to read the whole story.

Monday, November 12, 2012

Scope of warrant at issue

This just in from CyberCrime Review: "In United States v. Schlingloff, 2012 U.S. Dist. LEXIS 157272 (C.D. Ill. Oct. 24, 2012), Judge Shadid held that use of Forensic Toolkit's (FTK) Known File Filter (KFF) to alert on child pornography files was outside the scope of a warrant issued to look for evidence of identity theft.

The defendant in this case lived at a location that was searched pursuant to a valid warrant; the warrant was issued to find evidence of identity theft. During the search of the residence, multiple media devices and computers were retrieved, including a computer and external storage device belonging to the defendant. When the items were sent for forensic analysis, the computer forensic analyst did a search of the devices not only for identity theft (likely image and string searches), but also for child pornography using FTK's KFF option.

A short explanation on KFF. To make forensic analysis easier, files that are known to be valid (system files, DLLs, etc.) are hashed, and those hash values are compared against a disk image to exclude known valid files from further forensic analysis. Conversely, known malicious or illegal files are also hashed, and if those files are found on the computer, the KFF alerts on those hashes, indicating to the investigator that those files should definitely be investigated further. Per FTK's own literature, the KFF can be pared to certain file lists (i.e. hashes of child porn files, virus-related files, etc.) relevant to the current investigation. Additionally, the forensic investigator does not have to use KFF - it is merely an option.

Here, the investigator chose to use the KFF, and within its alerts were hashes of child pornography. While searching the defendant's computer, child porn alerts generated by the KFF showed up. The analyst took the next step and (to confirm the files were in fact CP), opened a few to confirm the results. As the court stated:
The search here did not end with flagging the child pornography files during preprocessing, however. After the KFF alerted to the two files in question, [the agent] believed that he recognized them to be part of the "Vicky" series of child pornography based on their hash values and his experience. Rather than stopping at this point to obtain a warrant to search for images of child pornography, [the agent] briefly opened each file in order to confirm his suspicions before stopping any further processing..

Based on this evidence, the defendant was charged with possession of child pornography. The defendant filed a motion to suppress the evidence, arguing that it was outside the scope of the warrant. The initial motion was denied because the court was under the impression that KFF was an all-or-nothing option. Upon learning that the KFF can be turned on and off in a motion to reconsider, the court granted the motion to suppress.

Continue reading the article by clicking here.


Friday, November 9, 2012

HFR 3D - coming soon to a theatre near you

Here's a collection of links on the emerging HFR 3D standard for video.

Thursday, November 8, 2012

variable frame rates

An interesting quirk in digital multimedia evidence (DME) when it meets the average first responder's workflow can cause unnecessary angst when using the Omnivore.

Here's what I mean.

Let's say that a crime happened and was captured by a CCTV system - and that the Omnivore is your tool of choice for retrieving the DME for use by your agency. The crime lasts only a minute or two, but the investigators want 15 minutes before and after the crime - thus your capture duration would be 32 minutes, give or take a few seconds. With me so far?

Enter a variable frame rate.

Some systems employ a variable frame rate for recording / playback. Thus, if nothing's happening, the frames per second (fps) might be set at 1 or 2 fps. Then action occurs in front of the camera, and the fps jumps up to 15-30 for the duration of the action.

So, in our scenario, there's little going on for about 15 minutes, then 2 minutes of action, then little going on for 15 minutes. The DVR manufacturer wants to maximize storage space, so it's 15 minutes x 2 fps + 2 minutes x 30 fps + 15 minutes x 2 fps (as opposed to 32 minutes x 30 fps. With me? Here's where this is going.

If you run the Optimization routine in Omnivore based on the initial seconds of the DME, it will give you an average playback of 2 and a capture rate of 4 fps. But what happens when 15 minutes later, the fps jumps to 30? Omnivore, if you have it selected to stop when it drops frames, will stop and ask you if you want to save your work. It thinks it's dropped a frame as it's being flooded with frames and isn't set to receive them at the new rate. It's doing what it's supposed to do.

The simple solution to this problem, if you can call it that, is to base your Optimization on the time within the video where the crime actually occurs - or there's action happening. This will be the highest rate, generally. You should also note the internal settings of the DVR. What does it say the frame rate should be for the camera that you are capturing? Is there a different fps setting for motion, alarms, panic buttons, etc.? Write this stuff down. Then compare what Omnivore says about the frame rate with your notes.


Wednesday, November 7, 2012

Nyquist Rate

The Omnivore, from Ocean Systems, is an essential part of my field kit. I've used it with great success on many cases. An interesting question came in related to it, it's Optimization process, and the accompanying instructions. Here's my answer.

While it's not explained or referenced, it appears that the software samples the playback rate, then uses a variation on the Nyquist Rate theme (The Nyquist-Shannon sampling theorem establishes that "when sampling a signal (e.g., converting from an analog signal to digital), the sampling frequency must be greater than twice the Band Width of the input signal in order to be able to reconstruct the original perfectly from the sampled version") in performing it's work.

It seems that the Omnivore is sampling (or capturing) at twice the playback rate, then discarding the duplicates to best re-create the proprietary file in a usable format.

So, from a workflow standpoint, you open the player, load the file, launch Omnivore .... and capture the video into Omnivore's proprietary format. With me so far.

What do you do when you have multiple clips from a single location - same player, many camera views? The Omnivore help files says this, The “Reset” button located in the Video Setting Tab (Optimization section) should only be used when you are changing from one player to another. If you are performing multiple captures of video from different camera views within the same player, you do not need to Re-Optimize each time or “Reset” the optimization process.

So in the case that generated the question, each of the individual views was playing back at a different rate - a rate that was variable. The only way to get an accurate grab was to Reset after playing back each view. Then Re-Optimize with the new camera view.

So, in this case, RTFM wasn't the best solution. Who knew?


Tuesday, November 6, 2012

Stabilization of video from helmet cam

If you're looking to stabilize video from a helmet cam, motorcycle mounted cam, or in-car video, here's a YouTube video to show you how easy it is to do in AmpedFIVE.


Monday, November 5, 2012

Reports from experts

I've noticed an increasing number of people presenting themselves as experts in the field of audio, video, image, and multi-media forensics. As the economy contracts, and people look for work slightly outside of their skill set, it's important to know that your work with Photoshop is just a portion of what you need to do for a case.

"As an expert witness, you may be asked to produce an Expert Witness report for the court.

When developing your expert witness report, remember that they are discoverable; that is, your report will be shared with the attorneys for all sides in the dispute prior to trial.

Your expert witness’s report should include all the pertinent findings that you observed, pertinent things that you sought but did not find, your conclusions based on your findings, and, if needed, a statement explaining the reasons for your conclusions. Because your conclusions are based on science, it should be possible for another person with your training to read your report and look at your documentation, such as photographs, and reach the same conclusions.

The quality of your work reflects your care and thoroughness and will help establish your reputation.

While reviewing a case, consider what points are important and need emphasis, as well as the best way to document your observations. Strive to describe an observation so that someone else, including yourself years later, can read the description and form an accurate mental image of what is described in the report.

Copies of your notes may be requested, so it is important to keep any documentation professional in nature; you would not want to be embarrassed because of a disparaging notation." - RTI International

Saturday, November 3, 2012

Photoshop enters the Presidential campaign

It's getting completely ridiculous. This image is floating around Twitter, seeming proof that the President is ... (fill in the blank as you see fit. this isn't political commentary).

But, as each side points fingers and works themselves into a froth, the real loser is Photoshop. As Photoshop has become a verb, requests to authenticate images become more frequent.

Yes, it's a cut/paste forgery. Our ELA test shows clear lines where the insertion has taken place. But you need not take my word for it. All one has to do is trace the source. The man admits it's a fake.

So, let's all take a deep breath. Vote with intelligence, not emotion. And, please, let's resist the urge to use Photoshop in such nasty ways. Let's make art, and clarify images - let's not use such a wonderful tool to confuse and anger and annoy. Help make Photoshop a noun again.

Friday, November 2, 2012

LAPD posts 'Grim Sleeper' suspect's photos on Facebook, Twitter

This from the LA Times: "Los Angeles police are again turning to the public for help in identifying dozens of women seen in photos found at the home of the alleged "Grim Sleeper" serial killer.

Forty-two photographs found at the home of suspect Lonnie Franklin Jr. will be posted on Facebook and Twitter on Thursday, Los Angeles police announced. The photos, taken between 1976 and 2010, were among about 1,000 photos seized from Franklin's home when he was arrested in July 2010.

Franklin, 60, has been charged with murder in the slayings of 10 women whose bodies were found on the streets of South Los Angeles over two decades. Authorities said he has been linked to at least six more killings.

When authorities found the photos, along with hundreds of hours of video, they feared that some of the women could be additional victims. Some of the images appeared to be innocent snapshots, but most showed women in various states of undress in sexual poses.

Detectives weeded out duplicate images and sought to identify about 160 women. They tried to contact the women on their own, but when they were unable to identify the rest, they took the rare step of making the images public. Hundreds of tips poured in, and detectives were able to identify additional victims."

Click here to read the whole story and visit the gallery.

Thursday, November 1, 2012

NIK now part of Google?

Did you know that Google bought NIK Software? A lot of folks like Nik Color Efex Pro and use it in their workflow. Well, NIK's now a Google property.

I'm not sure what this means for the future of Nik's tools, but at least you know. If you don't care for Google's privacy policies, you may want to click over and let them know that you don't want your user info migrated to Google.

Monday, October 29, 2012

Government Organizations can also be Sanctioned for Spoliation of Evidence

This from exterro.com: "The threat of evidence spoliation doesn’t only affect private parties but also extends to government organizations, such as cities or municipalities. Case in point is DMAC LLC and Fourmen Construction, Inc. v. City of Peekskill (S.D.N.Y Sept. 12, 2012). The district court ruled that the defendant, City of Peekskill, spoliated evidence by deleting relevant emails. This failure was due largely in part to the defendant not maintaining a “formal e-mail retention policy,” which left “sole discretion” to the defendant’s employees to decide for themselves whether to keep or dispose of emails. Along with awarding the plaintiffs, DMAC and Fourmen Construction, with costs and fees arising from bringing this motion, the court granted an adverse inference instruction, which allowed jurors to infer “that the City (defendant) negligently destroyed e-mails similar in nature to the ones produced, and that said e-mails would have been favorable to plaintiffs’ case.”

In this case, the plaintiffs brought suit against the defendant for stopping their real estate project allegedly due to illegal political reasons. During the discovery process, the defendant informed the plaintiffs that they had no formal email retention policy in place. As a result, a majority of the defendant’s employees had deleted pre-litigation emails concerning the subject matter relevant to the case. In response, the plaintiffs made discovery requests to third parties that surfaced several relevant emails from the defendant. Based on this finding, the plaintiffs filed a motion for sanctions against the defendant for spoliation of evidence under Federal Rules of Civil Procedure (FRCP)."

"The court deemed a failure to maintain a “formal e-mail retention policy” as de facto negligent. But beyond this, the court ruled that the defendant was grossly negligent because (1) the defendant ignored its obligation to preserve relevant emails when the duty to preserve was triggered, and (2) even with the defendant’s assurances that a legal hold was implemented when litigation began, testimony from one of the defendant’s employees refuted that claim. The employee stated that “at no time was she ever advised to preserve communications, including e-mails.”

Read the whole story here.

Friday, October 26, 2012

Adobe Camera Raw - no Win8 support yet

If you are an ACR user, and you want to upgrade to Windows 8 ... you'll have to wait a bit. Adobe's compatibility site shows no support for ACR for Win8 users. Additionally the ".com" stuff isn't supported yet. Neither is Flash (for those that develop demonstratives in Flash Pro).

So, stay tuned. It's always this way when a new OS hits the market.

Thursday, October 25, 2012

What you should know about Windows 8 security features

If your lab is considering upgrading to Windows 8, or looking to start the validation process, here's an article that outlines the new security features of Windows 8.

Considering that many of the students in my classes are still on XP, I wonder how many will jump straight to 8 - or simply stay with XP and hope for the best.

Wednesday, October 24, 2012

Image Processing Fundamentals

I'm heading down to San Diego to attend the annual LEVA conference and present a lecture on Image Processing Fundamentals. My topic doesn't concern a specific piece of software, or a new piece of hardware - it's about the science that underlies forensic video analysis and how to talk about it in everyday terms.

So from convolution (it takes a village) to why night vision shots are always green, we'll have a good time talking about the science behind the work that we do. Along the way, we'll meet some of the giants of the science world like Joseph Fourier (or Joey Sine Wave - as he's called in NYC) and Anil Jain.

I hope to see you there.

Tuesday, October 23, 2012

Learn new Photoshop features in a click

Created with Adobe Configurator 3, the Photoshop Features panel lets you easily explore, try out and learn the new and enhanced tools and features in Photoshop CS6 and Photoshop CS6 Extended. Arranged in a series of tabs, from the panel you can check out the new tools and features, access the timeline tools and capabilities for video and frames, go to video tutorial websites and if you have Photoshop Extended use all the major 3D tools and functions.

The panel is free and exclusively available on Adobe Exchange. To download it you will need the Adobe Exchange panel which currently works with 9 different CS6 applications.

Monday, October 22, 2012

U.S. Customs Workers to Switch to iPhones From BlackBerrys

Having a small hand in the cellphone forensics side of the DME business, I don't see the move to the iPhone as a good thing. I would hope that, rather than take the "fan boy" route, agencies fully validate the phones in terms of security, and just what the phone captures about the users' daily activities. I know what I can get from an iPhone - at the local police level using tools like Cellebrite and FinalMobile. I can imagine what the national security side looks like. Not good.

Friday, October 19, 2012

Creative Cloudy

Ok. This isn't right. I've just finished downloading all the CS6 apps via the Creative Cloud. Now, understand, I don't technically have internet up here on the ranch. Verizon's switch was fully populated for the mountain communities before I moved in, so I get internet through a cellular 3G link. So, I downloaded all the apps via cellular. Ouch.

But, it gets worse. When I finished downloading everything (about 2 gigs worth), and fired up Bridge CS6, the check for updates functionality kicked in and found another 700Mb in updates? Updates? I just downloaded the latest stuff from the Cloud. Why should there be updates? Ugh.

I'll click the update button and go to bed. In all, it'll take about 24 hours to download, install, and update the CS6 apps via 3G.

Have a great weekend.

Wednesday, October 17, 2012

Meet Amped Software at the LEVA Conference

This just in from Amped Software:

We are happy to announce that we’ll be present at the Law Enforcement & Emergency Services Video Association (LEVA) 2012 Annual Training Conference on October 22-26, 2012 at the BAHIA Hotel in San Diego, California.

We will be demonstrating and showcasing the new 2012 version of our popular Amped Five Professional forensic video enhancement software. VideoScanner, our new product for forensic video e-discovery, will be shown in action at our booth. This is a new tool that can save countless hours for investigators looking for video evidence on a suspect’s computer.

Training conferences like LEVA are very important for us: with respect to other kind of events, here we have the possibility to be in touch with our actual end users and meet with world class forensic video analysts. Here we can present our technology to experts who can fully understand its potential and give concrete feedback for its further improvement. For this reason we are presenting here not only our popular software for forensic video analysis, Amped Five, but also our latest projects.

In particular with VideoScanner we created a very simple tool which can save hours looking and inspecting video files in digital forensic cases. VideoScanner allows the investigator to quickly extract few representative frames to all the videos found on a device for a efficient inspection. As a bonus it add several forensic facilities, such as the possibility to calculate the hash code on all the analyzed files and the automatic creation of the analysis report.

We are using this conference to show a preview of Authenticate, our new project which for digital photo authentication. Authenticate will incorporate an innovative workflow concept into a ground-breaking software for image authentication within a feature-packed, but easy to use, user experience. We see this as a critical tool for prosecutors and investigators in states such as California in light of the recent Beckley court ruling on requirements for digital evidence authentication. Evidence is being challenged in courts on the basis of authenticity and Authenticate will provide several tools for evaluating the originality of an image. We are offering several types of tools in Authenticate and have combined several different techniques, from simple metadata and quantization table analysis to actual pixel value inspection and cutting edge techniques used to specifically match an image to a camera or device.

At LEVA, Amped Software will be in booth 122 in the main exhibit hall. We have donated a VideoScanner tool for the LEVA Door Prize Drawing. You have to be present to win, so we'll see you there!

Tuesday, October 16, 2012

I'm now an Adobe Creative Cloud subscriber

OK. I did it. I finally did it. I signed up for Adobe's Creative Cloud services. I'd like to say that I did it for work, but that's not entirely true. I did it for school. For all the things that I'm doing in my school work towards my PhD, it just made sense. Plus, the special offer that they made through the school was too hard to pass on. So, I did it. I'm in the cloud.

Wish me luck.

Monday, October 15, 2012

Art vs. Science

I'll be in court today as a spectator, watching two "experts" testify as to their work on the authenticity of a particular piece of evidence. These two people both "examined" a VHS tape. Each came to a separate conclusion as to the authenticity of the evidence. One has a process, a system, a set of tools that is recognized by his peers as valid, and institutional backing. The other, seemingly worked by feel - trusting his gut that things just didn't look right. One has a stack of notes that can be used to re-create his work. The other has several pages that only make sense to him. The scene is set ...

I'll have my smart phone at the ready, Tweeting live as interesting things come up. Follow me @jimhoerricks.

Wednesday, October 10, 2012

FourMatch in an Image Authentication Workflow

Four and Six recently posted the latest in a series of blog posts placing their new FourMatch authentication tool in context within the larger image authentication workflow.

" ... The biggest strength of FourMatch is its ability to provide compelling evidence that an image file has not been modified since it was first captured. However, FourMatch is not designed to tell you whether an image is untruthful. It merely tells you whether the photo remains in the pristine state it would be in coming direct from the camera. That means that many files that fail the FourMatch test may still be truthful images. Perhaps someone just cropped the image without altering the remaining photo content. Or perhaps someone just re-saved the photo using a higher degree of JPEG compression in order to make the file smaller to upload to the Internet. Both of these changes would cause the resulting file to fail the FourMatch test, even though the actual content of the file is still reliable ..."

" ... Let’s start with considering FourMatch as a standalone authentication measure. Particularly within a legal setting, there are many times when people may need assurance that an image can be trusted, particularly given the ease with which images can be manipulated with modern software ..." Two things come to mind, is it possible that an image is authentic, completely untouched by software, yet fail the test? Meet the black swan. Even though their database is quite robust, it still needs updating regularly. Thus, the software - given the tremendous head start - will play catch up as new phones and cameras come out. Not finding that black swan depends on keeping your subscription up to date, keeping your local database up to date, and Four and Six keeping their end up to date. Also, as it's software and it's database driven, can it be spoofed? Hmmm.

At this point, I think it's abundantly clear what FourMatch is and isn't. The question now is ... is it worth the initial price + on-going subscription (+ off-line surcharge for those folks who have an un-internet-connected lab) for what it provides? Given that a lot of folks haven't upgraded from Photoshop CS3, this cost also includes upgrading Photoshop as well.

Tuesday, October 9, 2012

Problems with CCTV evidence in court

This from Walesonline.com illustrates the problems in dealing with CCTV evidence: "... Jason Richards, 38, and Ben Hope, 39, are on trial accused of his murder and the attempted murder of his parents who had tried to stop their son from being attacked.

They both deny all the charges against them.

The jury had previously heard that that eight and a half years worth of CCTV material had been recovered during the investigation into the 17-year-old student’s death.

Earlier in the week DC James told the court he had viewed CCTV images from all over the city as part of the investigation.

The jury had also heard that around 100 to 120 cameras had been involved in the investigation and included images from public houses, private houses and commercial premises.

As part of the cross-examination of DC James which began today, Mr Rees pointed out that two clips taken from a camera at Talybont student accomodation couldn’t follow each other as the one later in sequence happened earlier in adjusted real time.

During the hearing DC James explained to the court how some differences in timings could occur.

He said it could be the case that an officer has rounded it down to the minute or up to the minute.

DC James added: “We try to be as accurate as we possibly can.”

The court heard that council cameras were treated as being accurate as they run to the atomic clock.

Mr Rees also read out in court a number of premises which had been asked to download their CCTV as part of the investigation.

He said Talybont student accommodation had been asked to do so on April 19 - eight days after Aamir had been killed.

Mr Rees said when the person responsible for doing this downloaded the images and checked it against the speaking clock they found CCTV was running 15 seconds faster than the speaking clock.

The court heard that when the North Star public house downloaded their CCTV and checked the timings they found the CCTV was running one hour and five minutes slower than the speaking clock.

DC James told the court that he would assume an officer would have been writing these timings down at the time.

He had also told the court that the CCTV team “can only work with the timings given [when the CCTV] was recovered”

The trial continues ...

Saturday, October 6, 2012

Understanding ISO, Shutter Speed, and Aperture

Check out this awesome exposure triangle graphic found in this Exposure Guide tutorial on the fundamentals of exposure.

"When these three elements are combined, they represent a given exposure value (EV) for a given setting. Any change in any one of the three elements will have a measurable and specific impact on how the remaining two elements react to expose the film frame or image sensor and how the image ultimately looks. For example, if you increase the f-stop, you decrease the size of the lens’ diaphragm thus reducing the amount of light hitting the image sensor, but also increasing the DOF (depth of field) in the final image. Reducing the shutter speed affects how motion is captured, in that this can cause the background or subject to become blurry. However, reducing shutter speed (keeping the shutter open longer) also increases the amount of light hitting the image sensor, so everything is brighter. Increasing the ISO, allows for shooting in lower light situations, but you increase the amount of digital noise inherent in the photo. It is impossible to make an independent change in one of the elements and not obtain an opposite effect in how the other elements affect the image, and ultimately change the EV."

If you’re just starting out in photography, do yourself a favor and work through the Photography Basics page over on Exposure Guide. It’s a fantastic resource.

Find more cool stuff at PetaPixel.

Friday, October 5, 2012

How do we store/manage all this digital media/data?

On October 23rd, LEVA is opening the doors of our exhibit hall and presentation rooms for our Digital Asset Management Expo at the Bahia Resort Hotel in San Diego. From 8:00 am to 6:00 pm, all law enforcement officials are encouraged to join us absolutely free of charge. Visit with our twenty-six exhibitors and attend presentations on the latest digital asset management technologies for law enforcement. The goal of this event is to help agencies everywhere answer the question, “How do we store/manage all this digital media/data?”

Topics presented will include;

· Digital audio enhancement & clarification
· 3D laser scanning for crime scene mapping & documentation
· Network based surveillance video systems
· Cost effective digital asset management platforms
· High definition in-car video recording
· High definition body-worn video recording
· Forensic video analysis solutions
· File based media movement & storage

Rooms at the Bahia hotel are still guaranteed available at the government rate ($133 per night) for a limited time. A lunch buffet will be served in the exhibit hall for $10 for those law enforcement professionals joining us for the day. If your agency has questions about handling, managing or storing digital evidence or data in its many forms, this is the place to be!

Please feel free to contact LEVA President Blaine Davison at president@leva.org or Training Vice President Jan Garvin at training@leva.org with any other questions regarding the event.

Thursday, October 4, 2012

Free J2K plugins

j2k is a free Photoshop and After Effects plug-in set for reading and writing the JPEG 2000 file format, the successor to JPEG.

Also known as JP2, JPEG 2000 uses wavelet compression as opposed to the DCT compression used in standard JPEG. The end result is "better image quality" in a smaller file. JP2 also includes mandatory metadata such as information about an image's color space.

The After Effects and Premiere Pro versions have the ability to Auto Proxy, meaning that when working at half or quarter resolution j2k will only need to read in a fraction of the file, resulting in dramatic speedups.

Find out more by clicking here.


Wednesday, October 3, 2012

Why don't cameras capture dynamic range as our eyes do?

Here's an interesting discussion on human vision, perception, and equipment.


Tuesday, October 2, 2012

Get a look at the new Acrobat XI

Click here to register for the webinar and get introduced to Adobe's newest version of Acrobat (XI). From what I've heard, it's gonna rock your presentations.

NYPD to boost gang unit over social media violence

Interesting timing, but this just in from WRAL (New York), " ... The New York Police Department is planning to double the size of its gang unit to 300 detectives to combat teen violence fueled by dares and insults traded on social media. ... Under the new plan, the NYPD gang unit will work more closely with other divisions that monitor social media for signs of trouble. ... Kelly cited a recent case in which investigators used Facebook to track a turf war between two Brooklyn crews named the Very Crispy Gangsters and the Rockstars. The case resulted in dozens of arrests for shootings and other mayhem ..."

Eventually, these cases will make it to court ... Images will need to be authenticated, processed, etc. Something to consider.


Monday, October 1, 2012

Interesting development - authentication of images

Here's an interesting development in the on-going struggle to scientifically authenticate images for use in court.

Last week, I took a look at the Four and Six product. Over the weekend, Amped Software announced a product specifically aimed at the context/content issues raised in authenticating digital images for use in court. Amped's Authenticate product looks to be what we've all been waiting for - a multi-pronged approach to examine the range of authentication questions in an scientifically supported way. If their other products are any indication of how this one will eventually shake out, you'll get a comprehensive report that features academic references/sources - an essential part of Frye and Daubert.

If you're wondering who's behind all the science and technology, check out this list. It continues to grow as they reach out further into the academic circles of the countries in which they sell their products. Nevertheless, it's quite impressive.

So, since this is a restricted product, if you're interested in learning more, you'll have to reach out to Amped directly through your LE e-mail account and face a little screening.

No word yet on pricing, so stay tuned ...


Friday, September 28, 2012

Free Video Previewer

This came in via the Yahoo forensic audio group (Thanks to Douglas Lacey): "URI DFC's Video Previewer is a free application that quickly processes a video and shows its key frames in a PDF file. It is particularly useful in investigations where watching a video is time consuming. It allows specification to select frames at equally spaced intervals, or to perform intelligent selection of frames based on scene changes. The Video Previewer is a free, unsupported, tool."

Click here to find out more and download the free application.


Thursday, September 27, 2012

FourMatch - the marketing review

I realize that I'll probably upset some people with the comments that I'm about to make. But, I saw the marketing graphics for the new FourMatch Photoshop plug-in from Four and Six ... and I was a little shocked. Read the graphic; Assess reliability of social media images. In the same picture, Authenticate images instantly.

Now, what does that mean to you? The picture of the person with the mobile phone, the text ... with FourMatch, I should be able to authenticate pictures that I find on social media ... right?


From their own blog, "It currently can only analyze images from digital cameras, mobile devices, and tablets ..."

Remember Beckley? Beckley involved the police's use of images from Facebook. The police downloaded pictures from the suspect's Facebook account to use during sentencing - showing gang affiliation - for a sentence enhancement. Big problem. The defendent claimed that the image had been manipulated.

In California, authentication requires either the person in the scene to say ... yes, that's me and that's the scene as I remember it. Or, the photographer says ... yes, that's my picture and it shows the scene accurately, etc. Or, some independent person applies some scientific method to authenticate the image - like you and I.

1. to establish as genuine.
2. to establish the authorship or origin of conclusively or unquestionably, chiefly by the techniques of scholarship: to authenticate a painting.
3. to make authoritative or valid.

With that in mind, I became interested in the FourMatch project/product. I need something to authenticate images from social media sites. Something that the court will recognize as accurate - and something that will work within the scientific method. Does FourMatch fit the bill for me? Unfortunately, no.

Of the five factors within the scientific method, FourMatch fails two rather significant ones.

First, I can refute the results presented in the window - in a manor of speaking. Here's my test. Let's say that I take a picture with my own phone. I upload the picture to my Facebook account. I download the picture to my computer. I load the downloaded image into Photoshop and use FourMatch - it flags it with the yellow ... probably not authenic, been processed flag. What?! It's my photo.

I'm the photographer, it's my phone, and it's my Facebook account. Who is right? Me, or the FourMatch determination that it's been manipulated and might not be authentic? I worry that, given the people involved in the project, that more weight would be given to the results of the plug-in's tests than my own testimony that it's my picture. But nevertheless, the content and context wasn't changed in any way. The only thing that happened was the upload - where Facebook recompresses the image. Facebook does that to every image. With this in mind, how can the marketing statement in the graphic (above, from their web site) be true?

In a blog post, the creators say, "It provides objective evidence that a file was not touched by any software application since the time it was first captured." If this is the case, that the plug-in works only on images that are direct from the camera and untouched by any application (as noted above, from their blog) - then you can't use the plug-in to authenticate or even assess images from social media. Social media sites recompress images on upload.

Then, there's the error rate issue. What's the instance of false negatives or false positives? FourMatch is a database driven product. It looks at the image vs. a database of camera info. For my assessment, using a popular US purchased mobile phone to take an image, the signature from the phone's imager will likely be found in the FourMatch database and it should give the image the green light. Yet, what about images from other phones, more obscure phones (not contained within the database) that are flagged yellow - further review. This is the same problem that I had with JPEG Snoop. Does the yellow, needs additional inquiry flag qualify as a false negative? Sure, for the Facebook tests FourMatch is right - it's been touched. But, it's possible to authenticate the image by other means. Again, does this qualify as a false negative? Would you be comfortable arguing this point in court?

If you hadn't read this, and you owned FourMatch ... it yellow-flagged your image, would you use the image in your case? Would you confidently proceed? Or, would you move on? In triage - it says the image has been processed, touched by software. What would you do?

So, does FourMatch provide objective evidence that a file wasn't touched by any software since capture? For the most part, yes - as long as the capture device's information is in the FourMatch database. In my tests, the database's problems were centered around mobile phones. Precisely the types of photos that we're concerned with. More people are ditching their point-and-shoot cameras in favour of the camera in their mobile. After all, who wants to carry around two pieces of gear when the cell phone pics can be directly uploaded to social media. People tend to flow to the easiest option. Remember, social media images largely come from we the people, not photojournalists with professional cameras.

Does FourMatch live up to it's own marketing slogan, assess the reliablility of social media images? No - it can't. Social media images are recompressed - touched by software.

If FourMatch really did work to authenicate social media images, it would be worth the price. I'd even pay a little more. But, most of my authenication requests come from folks who do not have the camera - or the allegations involve content/context issues (the other 2 of the 3 F's). As such, I'd have trouble justifying the expense for a database oriented triage tool.

For media outlets looking to verify the integrity of photos received from their field photographers and other sources ... I'm sure that this is a great tool and the editors will appreciate its ease of use. Generally, the cameras used by photojournalists will be present in the FourMatch database. But for law enforcement and criminal justice employees looking to authenticate social media images ... sorry. Wrong product.

Wednesday, September 26, 2012

Kinesense Player Manager special offer

Last month, I've reviewed the Kinesense Player Manager. Well, this month, the company is sweetening the deal ... offering a discount for folks who download and try the product.

Introductory offer: Download a Free 30 day Trial and get a 50% discount on your first order! The Player Manager is available as a single CPU licence (Normal price $500/ €389/ £298). Enterprise wide licences are available (discount pricing applies).

How cool is that?!

Tuesday, September 25, 2012

Authentication of images

Four and Six announced the release of their product recently. According to the company, "... Last month, I wrote a blog post about using the “3 F’s” to determine the authenticity of a photo. FourMatch is a tool for examining the first of these F’s, the File. Unlike many of the techniques we’ve detailed in this blog over the past year, FourMatch does not examine the photo itself, so it doesn’t look for inconsistencies in the image. Tools to handle these other F’s—Footprints and Flaws—will come later."

Ok. I'm not ready to publish my opinion on the product yet. However, I'll invite you to poke around their web site and ask these simple questions, given tight budgets and cutbacks, is FourMatch worth the $890 price tag? Does it add enough value to your workflow to justify the initial purchase price, plus the annual maintenance fees? Again, I'm not even hinting at my own opion in this matter - just asking you to formulate yours.


Monday, September 24, 2012

Fixing Field Shift

Often times, compression schemes conspire to ruin your ability to discern license plate number or other important details. Sometime, tearing - or field shifting - can get in the way of producing a clear image for court or for a BOLO flyer. Thankfully, there's an easy fix.

Here we have a typical traffic camera view. The camera is positioned so license/number plate details can be captured. But, the speed of the car, with the recording technology, makes it such that quickly viewing and recognizing the plate info is not possible (or accurate).

In AmpedFIVE, the fix is easy.

From the Filter Panel, select Field Shift.

The Filter Settings allow you to nudge the fields (both Upper and Lower) both Horizontally and Vertically. The results are updated in real time. In this case, the solution is just a few clicks away.

For presentation purposes, I used the Compare Original filter, then wrote out the file to post here. I think that you'll agree, fixing field shift problems in less than a minute - in a reliable and repeatable way, one that's supported by science and academic references - is a really cool thing given our growing workloads.


Friday, September 21, 2012

Image processing is a subclass of signal processing

"... we may acquire a natural image, process it to enhance the picture, compress it for transmission, and then encode and transmit it in some fashion over a digital network. On the other end, the image is decoded, decompressed, and displayed to create another signal (the visible light of the display). But that isn’t the end of the story: the signal is then received by the eyes, processed further, and interpreted in some fashion by our brain. From acquisition to interpretation, the initial signal may be transformed, modified, and retransmitted numerous times. In this example, the signal underwent more than 10 transformations ..."

When a signal has continuous domain and range, we usually call it analog. When a signal has discrete domain and range, we call it digital.

"... The spacing of discrete values in the domain of a signal is called the sampling of that signal. This is usually described in terms of some sampling rate–how many samples are taken per unit of each dimension. Examples include “samples per second”, “frames per second”, etc.

The spacing of discrete values in the range of a signal is called the quantization of that signal. Quantization is usually thought of as the number of bits per sample of the signal. Examples include “black and white images” (1 bit per pixel), “16-bit audio”, “24-bit color images”, etc ..." - B. Morse, BYU, On Signals and Images

Thursday, September 20, 2012

Update to AmpedFIVE

There a new update to AmpedFIVE that addresses the issue of the potential for the addition of colour information when performing unsharp mask or laplacian sharpening. Build 4156 adds the choice between Intensity and Color mode in Unsharp Masking and Laplacian Sharpening.

We've done this exercise in my Photoshop classes. How do you perform USM without adding colour to your image? How do you answer the answer, "Did you add anything to this image?" if you use USM in your workflow - and don't control the processes in some way so as to limit the adjustments to only the lightness/intensity information.

There's a number of ways to accomplish this task in Photoshop, as long as you know what's happening. You can work in LAB, and only sharpen the L channel. You can work on an adjustment layer and control the effect with the appropriate blending mode. In AmpedFIVE, it's now much easier - just select Intensity when performing your sharpening. How cool is that?!


Wednesday, September 19, 2012

The nature of perception

From David Kelley's classic, The Evidence of the Senses: " ... The normal adult human is not a tabula rasa. We bring to perception an enormous fund of background knowledge, and the act of perceiving is usually guided by the conscious purposes of expanding or applying that knowledge. Consider, for example, the role of attention. At any moment, the way in which one directs his attention affects what is perceived from among all the things that could be perceived, given present stimulation. It is doubtful that an act of attention is necessary for perceiving every object. Stimuli such as sudden chills, loud explosions, or noxious odors intrude themselves upon us quite apart from any conscious choice. But attention certainly can make the difference between perceiving or not perceiving an object-the classic examples being one's awareness of his clothes or of a low hum in the background. And the degree of attention to an object has a marked effect on the character of one's perceptual awareness of it. Thus there are major differences in the scope, clarity, and specificity of awareness-that is, in how much of the object is perceived-along a continuum of attention from objects at the edge of the visual field, to pocket change fingered absentmindedly, to the road ahead while one is driving, to a pen one has found at last among the litter on the desk, to the face of another person in conversation, to the riveting sound of a scratching at one's door late at night. ..."

The history of what a person attends to affects what it is possible for him to perceive in a given situation. Attention is the major factor in perceptual learning.

As you can see now, after a few posts on David Kelley's book, that the science of perception - and the philosophy of perception - are quite different.