How to recognize a fake picture

"Khuc Ngoc Vinh" wrote in message

Hi everyone,
I know Photoshop can be used to render the original picture in many ways. But I wonder if there is any program or tool to recognize a picture changed by a tool like Photoshop. Is this a complicated problem? Thanks in advance!

What do you mean "Fake".

A Picture is a Picture.

In the first instance what is "Real" about Photographs. They are, or were, just a Chemical reaction produced by the effect of light striking a sensitive material. Everything about them depends on the light and the sensitive material, and everything is variable.

So what is, or was, "Real" or "True"?

Ever since the invention of photography, people have been adjusting or improving Prints, and if they wanted they could re-photograph the print to produce a new negative, which could have made it look "Real".

Photoshop just makes it a bit easier, and a lot more convenient. There is no need to work in a Wet Dark Room, it can all be done in the light.

Why bother wondering what was done, or if anything was done.

Just enjoy the picture, or not, as the case may be.

Would you call any of the Old Master’s Paintings a Fake, just because the scene depicted, never really existed.

Was Michealangelo present at the Last Supper? How did he know what it looked like?

I personally would take great offense if anyone called any of my pictures, (Photoshopped or not), a Fake, .

Roy G

Khuc Ngoc Vinh wrote:

Hi everyone,
But I wonder if there is any program or tool to recognize a picture changed by a tool like Photoshop. Is this a complicated problem?

Hi there!

Sometimes you can easily distinguish which of the parts of the image were changed if you have the digitally composed original (rather than scanned from a printed version). This is done by applying a hue/saturation adjustment layer, and trying pulling the slide of saturation to the end (oversaturate the image). Now the parts that were added from another image will be saturated differently. The thresholds will mostly show up. However, if a cloning is done using the pixels of the same image, sometimes it is impossible to have the threshold so apparent. In cases were composition is done after unification of color scheme in both pictures, this test may also fail. However, try tweaking with adjustment layers’ other effects to see if any weird change may happen in certain areas. Other tries may include layer blending modes.

In all cases expert eye maybe so important.

Mohamed Al-Dabbagh
Senior Graphic Designer

Thanks a lot!
"Mohamed Al-Dabbagh" wrote in message

Khuc Ngoc Vinh wrote:

Hi everyone,
But I wonder if there is any program or tool to recognize a picture changed
by a tool like Photoshop. Is this a complicated problem?

Hi there!

Sometimes you can easily distinguish which of the parts of the image were changed if you have the digitally composed original (rather than scanned from a printed version). This is done by applying a hue/saturation adjustment layer, and trying pulling the slide of saturation to the end (oversaturate the image). Now the parts that were added from another image will be saturated differently. The thresholds will mostly show up. However, if a cloning is done using the pixels of the same image, sometimes it is impossible to have the threshold so apparent. In cases were composition is done after unification of color scheme in both pictures, this test may also fail. However, try tweaking with adjustment layers’ other effects to see if any weird change may happen in certain areas. Other tries may include layer blending modes.
In all cases expert eye maybe so important.

Mohamed Al-Dabbagh
Senior Graphic Designer

Oh, sorry for my word. My question is just to ask how to recognize the picture changed "a lot" by a tool like Photoshop, which becomes very "different" from the original.

"Roy" wrote in message

"Khuc Ngoc Vinh" wrote in message

Hi everyone,
I know Photoshop can be used to render the original picture in many ways. But I wonder if there is any program or tool to recognize a picture changed by a tool like Photoshop. Is this a complicated problem? Thanks in advance!

What do you mean "Fake".

A Picture is a Picture.

In the first instance what is "Real" about Photographs. They are, or were, just a Chemical reaction produced by the effect of light striking a sensitive material. Everything about them depends on the light and the sensitive material, and everything is variable.

So what is, or was, "Real" or "True"?
Ever since the invention of photography, people have been adjusting or improving Prints, and if they wanted they could re-photograph the print to produce a new negative, which could have made it look "Real".
Photoshop just makes it a bit easier, and a lot more convenient. There is no need to work in a Wet Dark Room, it can all be done in the light.
Why bother wondering what was done, or if anything was done.
Just enjoy the picture, or not, as the case may be.

Would you call any of the Old Master’s Paintings a Fake, just because the scene depicted, never really existed.

Was Michealangelo present at the Last Supper? How did he know what it looked like?

I personally would take great offense if anyone called any of my pictures, (Photoshopped or not), a Fake, .

Roy G

"Khuc Ngoc Vinh" wrote in
news:dan8la$2dbd$:

Hi everyone,
I know Photoshop can be used to render the original picture in many ways. But I wonder if there is any program or tool to recognize a picture changed by a tool like Photoshop. Is this a complicated problem? Thanks in advance!

Program No, It used to be easy to find changes in an image but almost impossible now, you can no longer trust photographs, miricales are indeed very easy and the impossible only takes a little time.

—
f=Ma well, nearly…

"Roy" wrote in message

"Khuc Ngoc Vinh" wrote in message

Hi everyone,
I know Photoshop can be used to render the original picture in many ways. But I wonder if there is any program or tool to recognize a picture changed by a tool like Photoshop. Is this a complicated problem? Thanks in advance!

What do you mean "Fake".

A Picture is a Picture.

In the first instance what is "Real" about Photographs. They are, or were, just a Chemical reaction produced by the effect of light striking a sensitive material. Everything about them depends on the light and the sensitive material, and everything is variable.

So what is, or was, "Real" or "True"?
Ever since the invention of photography, people have been adjusting or improving Prints, and if they wanted they could re-photograph the print to produce a new negative, which could have made it look "Real".
Photoshop just makes it a bit easier, and a lot more convenient. There is no need to work in a Wet Dark Room, it can all be done in the light.
Why bother wondering what was done, or if anything was done.
Just enjoy the picture, or not, as the case may be.

Would you call any of the Old Master’s Paintings a Fake, just because the scene depicted, never really existed.

Was Michealangelo present at the Last Supper? How did he know what it looked like?

I personally would take great offense if anyone called any of my pictures, (Photoshopped or not), a Fake, .

Roy G

The OP did not use the word "fake." Nor the words "Real" or "True." Your point is more easily made and more universal by noting the mere fact that a camera and your brain see a scene entirely differently. The camera sees; the brain interprets.

But the OP’s question addresses a totally different problem. To wit: whether the content or objects have been moved, inserted, obliterated, caricaturized, etc to suggest that something was or was not there in the original scene. It has become a vital issue in everyday journalism or law where it is critical whether an image has been edited to the point that it has been — "altered" — where the purpose is to vet the "authenticity" of photographic evidence or photo journalism.
Example: was that photo of Saddam Hussein in underwear "authentic" or was it edited to paste his head on another body?
Was that really Tom Cruise throwing a paint bomb at a psychiatrist’s office? etc. . . .

The question remains: Is there a foolproof method of vetting a photograph submitted as legal evidence or photo journalism?

I don’t know and am eagerly following this thread to find out.

"Trust everybody, but cut the cards!" — W.C. Fields

.. . . . patrick

"patrick" wrote in message

"Roy" wrote in message

"Khuc Ngoc Vinh" wrote in message

Hi everyone,
I know Photoshop can be used to render the original picture in many ways. But I wonder if there is any program or tool to recognize a picture changed by a tool like Photoshop. Is this a complicated problem? Thanks in advance!

What do you mean "Fake".
Roy G

The OP did not use the word "fake." Nor the words "Real" or "True." . . . . patrick

Ooops! Yes, it is, indeed in the subject line. The point remains . . . . .. . . . patrick

I recently saw a clip on Discovery Channel (www.discoverychannel.ca) where a group at Dalhousie University had a program to quickly analyze images and easily detect digital alterations. I’ll post a link if I can find it.

"Kingdom" wrote in message

"Khuc Ngoc Vinh" wrote in
news:dan8la$2dbd$:

Hi everyone,
I know Photoshop can be used to render the original picture in many ways. But I wonder if there is any program or tool to recognize a picture changed by a tool like Photoshop. Is this a complicated problem? Thanks in advance!

Program No, It used to be easy to find changes in an image but almost impossible now, you can no longer trust photographs, miricales are indeed very easy and the impossible only takes a little time.

—
f=Ma well, nearly…

"Kingdom" wrote in message

"Khuc Ngoc Vinh" wrote in
news:dan8la$2dbd$:

Program No, It used to be easy to find changes in an image but almost impossible now, you can no longer trust photographs, miricales are indeed very easy and the impossible only takes a little time.

Or you can use the saturation trick described by Mohamed Al-Dabbagh, or in some cases if there is a physical date stamp in the image, compare it to the modified date of the file? heh heh…

On Sat, 09 Jul 2005 13:18:44 GMT, Kingdom
wrote:

Program No, It used to be easy to find changes in an image but almost impossible now, you can no longer trust photographs, miricales are indeed very easy and the impossible only takes a little time.

Actually, if you didn’t have the original, you could *never* trust photographs. Or art for that matter. 🙂

—

Hecate – The Real One

Fashion: Buying things you don’t need, with money
you don’t have, to impress people you don’t like…

On Sat, 09 Jul 2005 17:48:52 GMT, "Morituri-|-Max" wrote:

"Kingdom" wrote in message

"Khuc Ngoc Vinh" wrote in
news:dan8la$2dbd$:

Program No, It used to be easy to find changes in an image but almost impossible now, you can no longer trust photographs, miricales are indeed very easy and the impossible only takes a little time.

Or you can use the saturation trick described by Mohamed Al-Dabbagh, or in some cases if there is a physical date stamp in the image, compare it to the modified date of the file? heh heh…

It also depends on how well it’s done. Most people who try to fake an image make one big mistake – the lighting doesn’t match. It can be subtle, but a trained eye can usually spot it.

—

Hecate – The Real One

Fashion: Buying things you don’t need, with money
you don’t have, to impress people you don’t like…

Mohamed Al-Dabbagh wrote:

Khuc Ngoc Vinh wrote:

Hi everyone,
But I wonder if there is any program or tool to recognize a picture changed by a tool like Photoshop. Is this a complicated problem?

Hi there!

Sometimes you can easily distinguish which of the parts of the image were changed if you have the digitally composed original (rather than scanned from a printed version).

You can also get a pretty good guess at what parts of the image are authentic by looking at noise. Cloning/painting/etc will tend to destroy noise, or change its profile. Objects moved from one picture to another (And especially between one device and another) show clear differences in the patterns and distribution of noise.

Cheres,
Nicholas Sherlock

Hecate wrote in
news::

On Sat, 09 Jul 2005 13:18:44 GMT, Kingdom
wrote:

Program No, It used to be easy to find changes in an image but almost impossible now, you can no longer trust photographs, miricales are indeed very easy and the impossible only takes a little time.

Actually, if you didn’t have the original, you could *never* trust photographs. Or art for that matter. 🙂

—

Hecate – The Real One

Fashion: Buying things you don’t need, with money
you don’t have, to impress people you don’t like…

For that reason they are no longer relied apon in court and can be easily chalenged, this is a double edged sword in that very reasonable photographs can be challenged, just enough to introduce doubt.

—
f=Ma well, nearly…

In article <dan8la$2dbd$>,
"Khuc Ngoc Vinh" wrote:

I know Photoshop can be used to render the original picture in many ways. But I wonder if there is any program or tool to recognize a picture changed by a tool like Photoshop. Is this a complicated problem? Thanks in advance!

It is an impossible problem.

A digital image is nothing but a series of numbers. There is not necessarily anything characteristic of an image which has been manipulated in any way; there’s no way to look at a digital image and tell whether or not those numbers have been changed by a computer.

—
Art, photography, shareware, polyamory, literature, kink: all at http://www.xeromag.com/franklin.html

tacit wrote:

It is an impossible problem.

A digital image is nothing but a series of numbers. There is not necessarily anything characteristic of an image which has been manipulated in any way;

Incorrect!

A digital image is a series of numbers? YES. But it is not a random sequence (noise). Once you say IMAGE, then there is a lot to be done without even looking at it. There are many intelligent software to deal with image, in a whole, without specifying certain selected areas, such as shadows and highlights, autocolor, finding edges, and many other techniques. These algorithms can easily keep track of the image lighting contours and try to decide which of the image parts are different, and in which way. Mathematics has dealt with image in an enormous number of ways, and days always carry new discoveries in this respect.

Mohamed Al-Dabbagh
Senior Graphic Designer

"Mohamed Al-Dabbagh" wrote in message

Once you say IMAGE, then there is a lot to be done
without even looking at it. There are many intelligent software to deal with image, in a whole, without specifying certain selected areas, respect.

Mohamed Al-Dabbagh
Senior Graphic Designer

Mohamed

I would be interested to know of any software which is capable of detecting such alterations!! The reason I ask is that I am aware that some of the British Police Scenes of Crime departments are currently changing to Digital cameras, I am told that after any investigation, the images are copied intact from the camera to a CD by some new sealed device, and forwarded to a processing centre??
The camera-man does not even get to see the image until it is processed – printed and sent back to him. I believe they consider this an adequate means of ensuring the veracity of the image!
Clearly it cannot ensure that, but at the moment there seems no alternative, unless conventional film is used, and of course, that could be tampered with in any case.
One service is using Nikon cameras and the camera connects directly to the device, which copies to a CD and erases the original?
Hope there is some sort of backup!

Harry

Harry Limey wrote:

I would be interested to know of any software which is capable of detecting such alterations!! The reason I ask is that I am aware that some of the British Police Scenes of Crime departments are currently changing to Digital cameras, I am told that after any investigation, the images are copied intact from the camera to a CD by some new sealed device, and forwarded to a processing centre??

Well Harry,

You have to remember that digital sequence of photos are only accurate within the limit of resolution of the frame. Most digital images sequences that come from video cameras are stored in JPEG lossy format frames. The great thing here is that FORGING a video camera output could be easily verified. I don’t know exactly nor heard about specific software. There are many criteria upon which architecture of this software is built such as:

1- Smooth lighting contours
2- Motion blur
3- Mixing of color schemes (quite apparent in skin tones) 4- Hairy details loss
5- Shadows generated by the objects
6- Highlights
7- Soft edges (feathers) cleanliness
8- Stains and artificial noise (such as watermarks)
9- Ambient environment correct reflections in the objects 10- Motion blur of the reflected environment
11- Black matte
12- White matte (using soft light layer blending mode)

However I am still be amazed for some really fabulous composition of movies like what I saw in (Hollow Man), the transformations scenes! Even in this highly perfected case, there are some people who will discover the procedure of composing it!

Mohamed Al-Dabbagh
Senior Graphic Designer

"tacit" wrote in message

In article <dan8la$2dbd$>,
"Khuc Ngoc Vinh" wrote:

I know Photoshop can be used to render the original picture in many ways. But I wonder if there is any program or tool to recognize a picture changed
by a tool like Photoshop. Is this a complicated problem? Thanks in advance!

It is an impossible problem.

A digital image is nothing but a series of numbers. There is not necessarily anything characteristic of an image which has been manipulated in any way; there’s no way to look at a digital image and tell whether or not those numbers have been changed by a computer.

Usually there is no way to tell by looking, but there are some powerful image analysis techniques to tell whether an image is a composite of others, and if not a composite, then if it has likely been manipulated otherwise. It’s about the statistical distribution of many factors.

In article <dan8la$2dbd$ says…

Hi everyone,
I know Photoshop can be used to render the original picture in many ways. But I wonder if there is any program or tool to recognize a picture changed by a tool like Photoshop. Is this a complicated problem? Thanks in advance!

For a program, that will show that an image has been "altered," you might want to look at ThumbsPlus (www.cerious.com). It will display a little "i" in the preview of the image, if it has been altered. Now the problem: this could be just a simple adjustment of color, or density – hardly a major revision. It could include the placement of another face onto a subject – a very major revision.

Unfortunately, as others have stated, you need to do a very precise viewing and analysis of the image. The "i" would only indicate that SOMETHING had been done. You would then have to scrutinize the image for exactly WHAT was done, and someone, who is good and carefuly, will leave few indications that a change was, in fact, done.

Good luck,
Hunt

Harry Limey wrote:

"Mohamed Al-Dabbagh" wrote in message

Once you say IMAGE, then there is a lot to be done
without even looking at it. There are many intelligent software to deal with image, in a whole, without specifying certain selected areas, respect.

Mohamed Al-Dabbagh
Senior Graphic Designer

Mohamed

I would be interested to know of any software which is capable of detecting such alterations!! The reason I ask is that I am aware that some of the British Police Scenes of Crime departments are currently changing to Digital cameras, I am told that after any investigation, the images are copied intact from the camera to a CD by some new sealed device, and forwarded to a processing centre??

Concerns about alterations arise in court, where one side is purporting to demonstrate something or other.

It’d be odd that a Police dept. would have such concerns when they’re in control of the process from start to finish.

—

John McWilliams

"Harry Limey" <harrylimey[@]lycos.co.uk> wrote in message

"Mohamed Al-Dabbagh" wrote in message

Once you say IMAGE, then there is a lot to be done
without even looking at it. There are many intelligent software to deal

with

image, in a whole, without specifying certain selected areas, respect.

Mohamed Al-Dabbagh
Senior Graphic Designer

Mohamed

I would be interested to know of any software which is capable of

detecting

such alterations!! The reason I ask is that I am aware that some of the British Police Scenes of Crime departments are currently changing to

Digital

cameras, I am told that after any investigation, the images are copied intact from the camera to a CD by some new sealed device, and forwarded

to

a processing centre??
The camera-man does not even get to see the image until it is processed – printed and sent back to him. I believe they consider this an adequate

means

of ensuring the veracity of the image!
Clearly it cannot ensure that, but at the moment there seems no

alternative,

unless conventional film is used, and of course, that could be tampered

with

in any case.
One service is using Nikon cameras and the camera connects directly to the device, which copies to a CD and erases the original?
Hope there is some sort of backup!

Harry

There is at least one digital camera manufacturer who sells a line of camera that record directly onto miniCD-ROM. I suppose you could always alter one and re-record it but it would be harder. I think that there’s also a push to get manufacturers to add something like a digital signature to the image that would — at least to some degree — validate it as an original file.

Norm

On Sun, 10 Jul 2005 00:12:07 GMT, Kingdom
wrote:

Actually, if you didn’t have the original, you could *never* trust photographs. Or art for that matter. 🙂

For that reason they are no longer relied apon in court and can be easily chalenged, this is a double edged sword in that very reasonable photographs can be challenged, just enough to introduce doubt.

Yes, I agree. However, it has always been true that the camera only sees what the photographer points it at, and only what he wants to include. I think the difference is that the general public has become far more aware of that than they used to be.

—

Hecate – The Real One

Fashion: Buying things you don’t need, with money
you don’t have, to impress people you don’t like…
—

Hecate – The Real One

Fashion: Buying things you don’t need, with money
you don’t have, to impress people you don’t like…

On Sun, 10 Jul 2005 09:34:24 -0700, John McWilliams
wrote:

I would be interested to know of any software which is capable of detecting such alterations!! The reason I ask is that I am aware that some of the British Police Scenes of Crime departments are currently changing to Digital cameras, I am told that after any investigation, the images are copied intact from the camera to a CD by some new sealed device, and forwarded to a processing centre??

Concerns about alterations arise in court, where one side is purporting to demonstrate something or other.

It’d be odd that a Police dept. would have such concerns when they’re in control of the process from start to finish.

Not really. It’s called Chain of Evidence. They have to prove in court that the image was taken in, at, and with , the conditions they claim it was and then not further altered in any way. It’s the same with all evidence.

—

Hecate – The Real One

Fashion: Buying things you don’t need, with money
you don’t have, to impress people you don’t like…

In article ,
"Mohamed Al-Dabbagh" wrote:

tacit wrote:

It is an impossible problem.

A digital image is nothing but a series of numbers. There is not necessarily anything characteristic of an image which has been manipulated in any way;

Incorrect!

A digital image is a series of numbers? YES. But it is not a random sequence (noise). Once you say IMAGE, then there is a lot to be done without even looking at it. There are many intelligent software to deal with image, in a whole, without specifying certain selected areas, such as shadows and highlights, autocolor, finding edges, and many other techniques. These algorithms can easily keep track of the image lighting contours and try to decide which of the image parts are different, and in which way. Mathematics has dealt with image in an enormous number of ways, and days always carry new discoveries in this respect.

For example there are techniques that can sometimes detect differences in the original sampling frequency of different parts of an image, revealing regions that have been replaced or transformed. Even if the whole thing has been resized after the fact, all resampling algorithms leave traces — essentially an invisible moiré pattern — that can be investigated by computers using mathematical methods like Fourier analysis. So while I agree with Tacit to the extent that a general solution covering all possible kinds of photomanipulation doesn’t exist, *most* of the commonly used techniques create evidence that the human eye, sophisticated image-processing systems, or both can detect — given sufficient resources and effort.

—
Odysseus

On 9 Jul 2005 03:26:29 -0700, "Mohamed Al-Dabbagh" reverently intoned upon the aether:

Khuc Ngoc Vinh wrote:

Hi everyone,
But I wonder if there is any program or tool to recognize a picture changed by a tool like Photoshop. Is this a complicated problem?

Hi there!

Sometimes you can easily distinguish which of the parts of the image were changed if you have the digitally composed original (rather than scanned from a printed version). This is done by applying a hue/saturation adjustment layer, and trying pulling the slide of saturation to the end (oversaturate the image). Now the parts that were added from another image will be saturated differently. The thresholds will mostly show up. However, if a cloning is done using the pixels of the same image, sometimes it is impossible to have the threshold so apparent. In cases were composition is done after unification of color scheme in both pictures, this test may also fail. However, try tweaking with adjustment layers’ other effects to see if any weird change may happen in certain areas. Other tries may include layer blending modes.
In all cases expert eye maybe so important.

Mohamed Al-Dabbagh
Senior Graphic Designer

Interesting technique, elegantly simple. Albeit, form a critical perspective all this really tells us is that a localized change occurred. This could be a soft edged selection used on a curves mask or cloning from an extraneous image. Still, it is very good starting place.

I think this is a test a forger could potentially craft an image to pass.

enjoy,

Sean

"In the End, we will remember not the words of our enemies, but the silence of our friends."

– Martin Luther King Jr. (1929-1968)

New Website
http://www.envisagement.com/
Last Updated 23 June 2005

I think this is a test a forger could potentially craft an image to pass.

Discussing techniques that focus specifically on how to detect fake images also provides help on how to make better fake images.

Usenet is the wild west of the Internet, and I’m rather proud of the fact that we are free to discuss anything we want. This is why I don’t plonk Scruff or Mike C, for example.

In that vein, here’s a suggestion of my own. Keep in mind that your ideas and suggestions might be used later to deceive someone.

If, in spite of this, you still decide to contribute your expertise to the discussion, I have no objection.
—

Mike Russell
www.curvemeister.com

On Wed, 13 Jul 2005 22:39:04 GMT, "Mike Russell" reverently intoned upon the
aether:

In that vein, here’s a suggestion of my own. Keep in mind that your ideas and suggestions might be used later to deceive someone.

I call that art. ;o) Actually, I occasionally fake things when paid or when my own work is outstanding modulo a few problems. The only place I worry about accuracy is when doing science or journalism. Otherwise, I just call my work photo illustration and skip all the issues.

And from a scientific perspective, I think I could craft an image in front of a jury that would be realistic beyond a reasonable doubt.

If, in spite of this, you still decide to contribute your expertise to the discussion, I have no objection.

In truth, I was actually looking at this suggestion as a way of checking for the quality of a manipulated image. Little things like this while not really visible (a small deviations in the signal), it is potentially something that could crop up in a billboard due to deviations in print runs for the different panels. Albeit, I have never been published in such a large format.

And in the end, unless it is a minor flaw in an otherwise great image or a rare scene, most manipulation is a waste of time as reshooting can be a lot faster. But when you do manipulate images (beyond mere color, contrast, and sharpness) it is nice to do it well.

The basics:

– Similar noise characteristics for all image elements. This can vary as images shift from focus to defocus (blurred).

– Similar lighting. Albeit, the use of flash in photography can make the lighting unreal in an unmanipulated image.

– Proper scale. Think shots with the full moon faked in.

– Similar color temperature. Again, the use of flash can create deviations in this. But dragging the shutter can somewhat ameliorate this in camera.

– Appropriate depth of field (DoF) that mimics the camera lens.

One could go on, but in the end it comes down to telling story (illustration) versus showing the reality (which the camera does not capture in truth). After all, the camera never lies, but it often deceives.

As for Mike C., I enjoy his play. But then, I can also admit 10 years ago he would have made me very angry.

enjoy,

Sean

"In the End, we will remember not the words of our enemies, but the silence of our friends."

– Martin Luther King Jr. (1929-1968)

New Website
http://www.envisagement.com/
Last Updated 23 June 2005

Mike Russell wrote:

In that vein, here’s a suggestion of my own. Keep in mind that your ideas and suggestions might be used later to deceive someone.

Hi Mike!

Science is always a sword of double edges. So you can use it in evil and good. Expertise, for example, in forging images or discovering forgery could help both of good and sick user to do what they like. Well, virtually everything in this world has this characteristic. Electricity can revive AND can kill. Expect that everything about image forgery has been tackled in a way or another. Still, we need to know about these things in-depth, and I really thank OP. Fortunately, 95% of image forgery could be discovered. But look at the bright side of story: we always face the problem of composing an image out of some images to produce an excellent work for publishing. The perfect image composition will produce a perfect work.

You are one of the best people in curves mastering, your work and expertise can also be a sword of double edges. It can, also, be used to add perfection to the composed (forged) images. If you know that your work and research was used to hurt people, because some sick user made advantage out of it, will you stop teaching people or stop research in curves? I doubt that!

Mohamed Al-Dabbagh
Senior Graphic Designer

"Mohamed Al-Dabbagh" wrote in message

Mike Russell wrote:

In that vein, here’s a suggestion of my own. Keep in mind that your ideas
and suggestions might be used later to deceive someone.

Hi Mike!

Science is always a sword of double edges. So you can use it in evil and good. Expertise, for example, in forging images or discovering forgery could help both of good and sick user to do what they like. Well, virtually everything in this world has this characteristic. Electricity can revive AND can kill. Expect that everything about image forgery has been tackled in a way or another. Still, we need to know about these things in-depth, and I really thank OP. Fortunately, 95% of image forgery could be discovered. But look at the bright side of story: we always face the problem of composing an image out of some images to produce an excellent work for publishing. The perfect image composition will produce a perfect work.

You are one of the best people in curves mastering, your work and expertise can also be a sword of double edges. It can, also, be used to add perfection to the composed (forged) images. If you know that your work and research was used to hurt people, because some sick user made advantage out of it, will you stop teaching people or stop research in curves? I doubt that!

Yes, curves may be used for good or evil, but that does not free us, as technology holders, from the responsibility of deciding what specific use our expertise will be put to. Each of us should decide that for ourselves, and not simply be drawn into a new technical problem for its own sake.

One thing that I can contribute to this thread is the concept of using encryption-based digital signature technology – like that already used to ensure the integrity of financial transfers – to create signed digital photographs. If a camera at a crime scene, for example, is connected to the internet, the image captured by the camera may be digitally signed using the private key of the photographer, and a key generated by a time server.

This would establish, within the limits of encryption technology, that a particular person took a particular image at a particular time. This, combined with their testimony of the photographer regarding the picture, would establish a chain of custody. The validity of the signed electronic document would guarantee that the bits had not been modified since their capture by the camera.

The result would be more airtight than film, which might have been modified or replaced at some point during the taking of the original photograph, e.g. the developing, and storage of the film and prints.

In addition, any other digital data, such as recorded material, images of fingerprints, or scanned documents, can be included in the same signed document. The security requirements for chain of custody would be minimal. As long as the digital material is not lost or destroyed, it’s chain of custody is provable in a way that is very difficult to achieve with physical evidence.

Far from being less reliable as evidence than film, digital has huge potential for being much more reliable, and at lower cost and security requirements, than physical evidence.
—

Mike Russell
www.curvemeister.com

"Mike Russell" wrote in message

"Mohamed Al-Dabbagh" wrote in message

Mike Russell wrote:

In that vein, here’s a suggestion of my own. Keep in mind that your ideas
and suggestions might be used later to deceive someone.

Hi Mike!

Science is always a sword of double edges. So you can use it in evil and good. Expertise, for example, in forging images or discovering forgery could help both of good and sick user to do what they like. Well, virtually everything in this world has this characteristic. Electricity can revive AND can kill. Expect that everything about image forgery has been tackled in a way or another. Still, we need to know about these things in-depth, and I really thank OP. Fortunately, 95% of image forgery could be discovered. But look at the bright side of story: we always face the problem of composing an image out of some images to produce an excellent work for publishing. The perfect image composition will produce a perfect work.

You are one of the best people in curves mastering, your work and expertise can also be a sword of double edges. It can, also, be used to add perfection to the composed (forged) images. If you know that your work and research was used to hurt people, because some sick user made advantage out of it, will you stop teaching people or stop research in curves? I doubt that!

Yes, curves may be used for good or evil, but that does not free us, as technology holders, from the responsibility of deciding what specific use our expertise will be put to. Each of us should decide that for

ourselves,

and not simply be drawn into a new technical problem for its own sake.
One thing that I can contribute to this thread is the concept of using encryption-based digital signature technology – like that already used to ensure the integrity of financial transfers – to create signed digital photographs. If a camera at a crime scene, for example, is connected to the internet, the image captured by the camera may be digitally signed

using

the private key of the photographer, and a key generated by a time

server.

This would establish, within the limits of encryption technology, that a particular person took a particular image at a particular time. This, combined with their testimony of the photographer regarding the picture, would establish a chain of custody. The validity of the signed

electronic

document would guarantee that the bits had not been modified since their capture by the camera.

The result would be more airtight than film, which might have been

modified

or replaced at some point during the taking of the original photograph,

e.g.

the developing, and storage of the film and prints.

In addition, any other digital data, such as recorded material, images of fingerprints, or scanned documents, can be included in the same signed document. The security requirements for chain of custody would be

minimal.

As long as the digital material is not lost or destroyed, it’s chain of custody is provable in a way that is very difficult to achieve with

physical

evidence.

Far from being less reliable as evidence than film, digital has huge potential for being much more reliable, and at lower cost and security requirements, than physical evidence.
—

Mike Russell
www.curvemeister.com

"Mike Russell" posted:
"…
One thing that I can contribute to this thread is the concept of using encryption-based digital signature technology
…."

Canon already has a kit to do something similar for image verification in "legal situations" … although I believe it uses a slightly different scheme. It apparently calculates some kind of digital signature from the image file, and records that signature as part of the image. The existence of any change(s) to the image are revealed when the image is compared to the signature.

"RSD99" wrote in message

"Mike Russell" wrote in message

"Mohamed Al-Dabbagh" wrote in message

Mike Russell wrote:

In that vein, here’s a suggestion of my own. Keep in mind that your ideas
and suggestions might be used later to deceive someone.

Hi Mike!

Science is always a sword of double edges. So you can use it in evil and good. Expertise, for example, in forging images or discovering forgery could help both of good and sick user to do what they like. Well, virtually everything in this world has this characteristic. Electricity can revive AND can kill. Expect that everything about image forgery has been tackled in a way or another. Still, we need to know about these things in-depth, and I really thank OP. Fortunately, 95% of image forgery could be discovered. But look at the bright side of story: we always face the problem of composing an image out of some images to produce an excellent work for publishing. The perfect image composition will produce a perfect work.

You are one of the best people in curves mastering, your work and expertise can also be a sword of double edges. It can, also, be used to add perfection to the composed (forged) images. If you know that your work and research was used to hurt people, because some sick user made advantage out of it, will you stop teaching people or stop research in curves? I doubt that!

Yes, curves may be used for good or evil, but that does not free us, as technology holders, from the responsibility of deciding what specific use our expertise will be put to. Each of us should decide that for

ourselves,

and not simply be drawn into a new technical problem for its own sake.
One thing that I can contribute to this thread is the concept of using encryption-based digital signature technology – like that already used to ensure the integrity of financial transfers – to create signed digital photographs. If a camera at a crime scene, for example, is connected to the internet, the image captured by the camera may be digitally signed

using

the private key of the photographer, and a key generated by a time

server.

This would establish, within the limits of encryption technology, that a particular person took a particular image at a particular time. This, combined with their testimony of the photographer regarding the picture, would establish a chain of custody. The validity of the signed

electronic

document would guarantee that the bits had not been modified since their capture by the camera.

The result would be more airtight than film, which might have been

modified

or replaced at some point during the taking of the original photograph,

e.g.

the developing, and storage of the film and prints.

In addition, any other digital data, such as recorded material, images of fingerprints, or scanned documents, can be included in the same signed document. The security requirements for chain of custody would be

minimal.

As long as the digital material is not lost or destroyed, it’s chain of custody is provable in a way that is very difficult to achieve with

physical

evidence.

Far from being less reliable as evidence than film, digital has huge potential for being much more reliable, and at lower cost and security requirements, than physical evidence.
—

Mike Russell
www.curvemeister.com

"Mike Russell" posted:
"…
One thing that I can contribute to this thread is the concept of using encryption-based digital signature technology
…"

Canon already has a kit to do something similar for image verification in "legal situations" … although I believe it uses a slightly different scheme. It apparently calculates some kind of digital signature from the image file, and records that signature as part of the image. The existence of any change(s) to the image are revealed when the image is compared to the signature.

Could be as simple as a checksum on each color.

.. . .. patrick

On Sat, 16 Jul 2005 01:41:21 GMT, "patrick" wrote:

Canon already has a kit to do something similar for image verification in "legal situations" … although I believe it uses a slightly different scheme. It apparently calculates some kind of digital signature from the image file, and records that signature as part of the image. The existence of any change(s) to the image are revealed when the image is compared to the signature.

Could be as simple as a checksum on each color.

….which could be easily altered…

—

Hecate – The Real One

Fashion: Buying things you don’t need, with money
you don’t have, to impress people you don’t like…

"patrick" wrote in message

"…
One thing that I can contribute to this thread is the concept of using encryption-based digital signature technology
…"

Canon already has a kit to do something similar for image verification

in

"legal situations" … although I believe it uses a slightly different scheme. It apparently calculates some kind of digital signature from

the

image file, and records that signature as part of the image. The

existence

of any change(s) to the image are revealed when the image is compared

to

the signature.

Could be as simple as a checksum on each color.

. . .. patrick

The model description is ‘Data Verification Kit DVK-E2’ … and the description is

= = = = = Begin Quote = = = = =
The Canon EOS-1Ds Mark II and EOS 20D digital cameras can prove it’s images are unaltered, original files. The Data Verification Kit DVK-E2, consisting of a dedicated memory card, a Secure Mobile (SM) card reader, and special software for Windows 2000/XP is able to verify that EOS-1Ds Mark II and EOS 20D image files are absolutely unaltered. The system is so precise, that even the slightest discrepancy is detected. This may well be a landmark for digital imaging in law enforcement and other documentary uses.

When the EOS-1Ds Mark II and EOS 20D user shoots with the verification system activated (P.Fn-31), a code is automatically generated based on the image contents and attached to the image. When the image is viewed, the data verification software determines the code for the image and compares it with the attached code. If the photo has been retouched in any way, the codes will not match, thus verifying that the image is not the original. = = = = = End Quote = = = = =

Review at
http://www.popphoto.com/article.asp?section_id=4&article _id=1161&page_numbe r=2&preview=

http://www.dpreview.com/news/article_print.asp?date=0401&amp ;article=04012903ca nondvke2

http://www.livejournal.com/~cannibal/163674.html?mode=reply

Searching for an ‘exact match on the string

Data Verification Kit DVK-E2

Came up with over a hundred hits, some of them fairly ‘technical.’ I think that it is probably a little more complicated than just a simple checksum.

"RSD99" wrote in message

"patrick" wrote in message

"…
One thing that I can contribute to this thread is the concept of using encryption-based digital signature technology
…"

Canon already has a kit to do something similar for image verification

in

"legal situations" … although I believe it uses a slightly different scheme. It apparently calculates some kind of digital signature from

the

image file, and records that signature as part of the image. The

existence

of any change(s) to the image are revealed when the image is compared

to

the signature.

Could be as simple as a checksum on each color.

. . .. patrick

The model description is ‘Data Verification Kit DVK-E2’ … and the description is

= = = = = Begin Quote = = = = =
The Canon EOS-1Ds Mark II and EOS 20D digital cameras can prove it’s images
are unaltered, original files. The Data Verification Kit DVK-E2, consisting
of a dedicated memory card, a Secure Mobile (SM) card reader, and special software for Windows 2000/XP is able to verify that EOS-1Ds Mark II and EOS
20D image files are absolutely unaltered. The system is so precise, that even the slightest discrepancy is detected. This may well be a landmark for
digital imaging in law enforcement and other documentary uses.
When the EOS-1Ds Mark II and EOS 20D user shoots with the verification system activated (P.Fn-31), a code is automatically generated based on the image contents and attached to the image. When the image is viewed, the data verification software determines the code for the image and compares it with the attached code. If the photo has been retouched in any way, the codes will not match, thus verifying that the image is not the original. = = = = = End Quote = = = = =

Review at
http://www.popphoto.com/article.asp?section_id=4&article _id=1161&page_numbe r=2&preview=

http://www.dpreview.com/news/article_print.asp?date=0401&amp ;article=04012903ca nondvke2

http://www.livejournal.com/~cannibal/163674.html?mode=reply
Searching for an ‘exact match on the string

Data Verification Kit DVK-E2

Came up with over a hundred hits, some of them fairly ‘technical.’ I think that it is probably a little more complicated than just a simple checksum.

Terrific! I was getting the impression that the problem was ironclad. That’s a great service that Canon is providing both photo journalists and the legal system.
I’m impressed! Thanks for the leads.
.. . . . patrick

"Hecate" wrote in message

On Sat, 16 Jul 2005 01:41:21 GMT, "patrick" wrote:

Canon already has a kit to do something similar for image verification

in

"legal situations" … although I believe it uses a slightly different scheme. It apparently calculates some kind of digital signature from

the

image file, and records that signature as part of the image. The

existence

of any change(s) to the image are revealed when the image is compared

to

the signature.

Could be as simple as a checksum on each color.

…which could be easily altered…

How about each individual camera is programmed to add a digital signature using, say, some sort of public key cryptography, to each image which includes various information about the picture, maybe checksums of several different sorts? As long as the digital signature isn’t forgeable (which any good implementation of public key cryptography isn’t), there’d be at least some way to demonstrate which camera took the picture and maybe some additional information as well.

Norm

"patrick" wrote in message

"RSD99" wrote in message

"patrick" wrote in message

"…
One thing that I can contribute to this thread is the concept of using encryption-based digital signature technology
…"

Canon already has a kit to do something similar for image verification

in

"legal situations" … although I believe it uses a slightly different scheme. It apparently calculates some kind of digital signature from

the

image file, and records that signature as part of the image. The

existence

of any change(s) to the image are revealed when the image is compared

to

the signature.

Could be as simple as a checksum on each color.

. . .. patrick

The model description is ‘Data Verification Kit DVK-E2’ … and the description is

= = = = = Begin Quote = = = = =
The Canon EOS-1Ds Mark II and EOS 20D digital cameras can prove it’s images
are unaltered, original files. The Data Verification Kit DVK-E2, consisting
of a dedicated memory card, a Secure Mobile (SM) card reader, and special software for Windows 2000/XP is able to verify that EOS-1Ds Mark II and EOS
20D image files are absolutely unaltered. The system is so precise, that even the slightest discrepancy is detected. This may well be a landmark for
digital imaging in law enforcement and other documentary uses.
When the EOS-1Ds Mark II and EOS 20D user shoots with the verification system activated (P.Fn-31), a code is automatically generated based on the
image contents and attached to the image. When the image is viewed, the data verification software determines the code for the image and compares it with the attached code. If the photo has been retouched in any way, the
codes will not match, thus verifying that the image is not the original. = = = = = End Quote = = = = =

Review at
http://www.popphoto.com/article.asp?section_id=4&article _id=1161&page_numbe r=2&preview=

http://www.dpreview.com/news/article_print.asp?date=0401&amp ;article=04012903ca nondvke2

http://www.livejournal.com/~cannibal/163674.html?mode=reply
Searching for an ‘exact match on the string

Data Verification Kit DVK-E2

Came up with over a hundred hits, some of them fairly ‘technical.’ I think
that it is probably a little more complicated than just a simple checksum.

Terrific! I was getting the impression that the problem was ironclad. That’s a great service that Canon is providing both photo journalists and the legal system.
I’m impressed! Thanks for the leads.
. . . . patrick

"patrick" wrote in message

"RSD99" wrote in message

"patrick" wrote in message

"…
One thing that I can contribute to this thread is the concept of using encryption-based digital signature technology
…"

Canon already has a kit to do something similar for image verification

in

"legal situations" … although I believe it uses a slightly different scheme. It apparently calculates some kind of digital signature from

the

image file, and records that signature as part of the image. The

existence

of any change(s) to the image are revealed when the image is compared

to

the signature.

Could be as simple as a checksum on each color.

. . .. patrick

The model description is ‘Data Verification Kit DVK-E2’ … and the description is

= = = = = Begin Quote = = = = =
The Canon EOS-1Ds Mark II and EOS 20D digital cameras can prove it’s images
are unaltered, original files. The Data Verification Kit DVK-E2, consisting
of a dedicated memory card, a Secure Mobile (SM) card reader, and special software for Windows 2000/XP is able to verify that EOS-1Ds Mark II and EOS
20D image files are absolutely unaltered. The system is so precise, that even the slightest discrepancy is detected. This may well be a landmark for
digital imaging in law enforcement and other documentary uses.
When the EOS-1Ds Mark II and EOS 20D user shoots with the verification system activated (P.Fn-31), a code is automatically generated based on the
image contents and attached to the image. When the image is viewed, the data verification software determines the code for the image and compares it with the attached code. If the photo has been retouched in any way, the
codes will not match, thus verifying that the image is not the original. = = = = = End Quote = = = = =

Review at
http://www.popphoto.com/article.asp?section_id=4&article _id=1161&page_numbe r=2&preview=

http://www.dpreview.com/news/article_print.asp?date=0401&amp ;article=04012903ca nondvke2

http://www.livejournal.com/~cannibal/163674.html?mode=reply
Searching for an ‘exact match on the string

Data Verification Kit DVK-E2

Came up with over a hundred hits, some of them fairly ‘technical.’ I think
that it is probably a little more complicated than just a simple checksum.

Terrific! I was getting the impression that the problem was ironclad. That’s a great service that Canon is providing both photo journalists and the legal system.
I’m impressed! Thanks for the leads.
. . . . patrick

yeah good answer
interesting thread

On Sun, 17 Jul 2005 15:50:03 GMT, "Norm Dresner" wrote:

Could be as simple as a checksum on each color.

…which could be easily altered…

How about each individual camera is programmed to add a digital signature using, say, some sort of public key cryptography, to each image which includes various information about the picture, maybe checksums of several different sorts? As long as the digital signature isn’t forgeable (which any good implementation of public key cryptography isn’t), there’d be at least some way to demonstrate which camera took the picture and maybe some additional information as well.

That would make far more sense. IMHO, the only way it could work is with some form of cryptography.

—

Hecate – The Real One

Fashion: Buying things you don’t need, with money
you don’t have, to impress people you don’t like…

On Sun, 17 Jul 2005 15:51:20 -0400, "KatWoman" wrote:

Terrific! I was getting the impression that the problem was ironclad. That’s a great service that Canon is providing both photo journalists and the legal system.
I’m impressed! Thanks for the leads.
. . . . patrick

I’m not so sure you’ll find very many photojournalists who are interested <g> but for law enforcement and legal work, that looks really good.

—

Hecate – The Real One

Fashion: Buying things you don’t need, with money
you don’t have, to impress people you don’t like…