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Detecting If a Photo Has Been Edited -- How?

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Anonymous
July 30, 2005 6:17:17 PM

Archived from groups: rec.photo.digital (More info?)

Let me start by saying I do not intend to enter any of these contests,
much less violate their rules -- I'm just curious as to how they
enforce them.

It you read the rules for this photo contest website you will see they
prohibit many image editing techniques.
http://www.dpchallenge.com/challenge_rules.php

My question is, how do they know? How would they know if I enhanced
the image using various Photoshop techniques?

For example, "spot editing" is prohibited in one of their contest
classes. How would they know if I darkened or lightened a selected
area if it is done so it's not obvious when viewing the image? This
is but one example of many I can think of.

Ken

More about : detecting photo edited

Anonymous
July 30, 2005 6:30:44 PM

Archived from groups: rec.photo.digital (More info?)

I dunno, my father-in-law could tell by sight where the lines were
where I had dodged and cloned out some artifact lines from a
photomerege....

Another time, I used clone to get rid of 10 houses from a sunset
landscape, and I could still tell too. I bet someoene looking for it
would have caught it too. Resized to 50% the effect was un-noticable
though.

Does that mean that I cant merge photo's to make a landscape and enter
that? That's silly. I took all of the images. George Lucas took the
wheel of a speeder with vaseline on the lens. That was "cheating". Now
we just cheat digitally. Who cares as long as the picture rocks! People
buying stock dont car that you airbrushed Gwen Stefani's pimple scars
out. Why should they care about removing houses and power lines?

People are weird.

The outdoor photographer annual landscape special had a peice about a
guy who take two exposures of the same subject, one normal, and one
with weird ISO/exposure/out of focus, and sandwiches them together and
prbably gets thousands for his photos. But he'd probably be excluded
from these contests. It's a joke. Art is art.
Anonymous
July 30, 2005 6:38:00 PM

Archived from groups: rec.photo.digital (More info?)

Ken Hall wrote:

> Let me start by saying I do not intend to enter any of these contests,
> much less violate their rules -- I'm just curious as to how they
> enforce them.
>
> It you read the rules for this photo contest website you will see they
> prohibit many image editing techniques.
> http://www.dpchallenge.com/challenge_rules.php
>
> My question is, how do they know? How would they know if I enhanced
> the image using various Photoshop techniques?
>
> For example, "spot editing" is prohibited in one of their contest
> classes. How would they know if I darkened or lightened a selected
> area if it is done so it's not obvious when viewing the image? This
> is but one example of many I can think of.
>
> Ken


I recall seeing on the news recently some image scientist expert saying he
had developed some software to detect image editing, useful e.g. to know if
someone had altered a security videotape, etc. Perhaps the contest has such
software, or similar software. But otherwise I should think it would be
next to impossible unless the image editing done was overtly obvious.
Related resources
Anonymous
July 30, 2005 7:03:00 PM

Archived from groups: rec.photo.digital (More info?)

On Sat, 30 Jul 2005 14:38:00 -0500, Proteus <nospam@nowhere.net>
wrote:

>I recall seeing on the news recently some image scientist expert saying he
>had developed some software to detect image editing, useful e.g. to know if
>someone had altered a security videotape, etc. Perhaps the contest has such
>software, or similar software. But otherwise I should think it would be
>next to impossible unless the image editing done was overtly obvious.

I wondered it their might be telltale signs in the histogram?

Ken
Anonymous
July 30, 2005 8:05:27 PM

Archived from groups: rec.photo.digital (More info?)

"Ken Hall" <kenhall2REMOVE@houston.rr.com> wrote in message
news:krjne1dtqppqsvltch0i3a5rlih3ddip97@4ax.com...
> Let me start by saying I do not intend to enter any of these contests,
> much less violate their rules -- I'm just curious as to how they
> enforce them.
>
> It you read the rules for this photo contest website you will see they
> prohibit many image editing techniques.
> http://www.dpchallenge.com/challenge_rules.php
>
> My question is, how do they know? How would they know if I enhanced
> the image using various Photoshop techniques?
>
> For example, "spot editing" is prohibited in one of their contest
> classes. How would they know if I darkened or lightened a selected
> area if it is done so it's not obvious when viewing the image? This
> is but one example of many I can think of.

Don't know but here is a fun site:
http://www.museumofhoaxes.com/tests/hoaxphototest.html
Anonymous
July 30, 2005 9:19:25 PM

Archived from groups: rec.photo.digital (More info?)

Ken Hall wrote:
> Let me start by saying I do not intend to enter any of these contests,
> much less violate their rules -- I'm just curious as to how they
> enforce them.
>
> It you read the rules for this photo contest website you will see they
> prohibit many image editing techniques.
> http://www.dpchallenge.com/challenge_rules.php
>
> My question is, how do they know? How would they know if I enhanced
> the image using various Photoshop techniques?
>
> For example, "spot editing" is prohibited in one of their contest
> classes. How would they know if I darkened or lightened a selected
> area if it is done so it's not obvious when viewing the image? This
> is but one example of many I can think of.

Might be they just demand an original RAW file / slide / negative from
the contest winners to compare with the entered image? This would give
an idea of what changes were made to the entered image, like spot clones
and levels/color corrections.

Is it practicably possible to edit a RAW file and save it in the same
RAW format?

Bob ^,,^
July 30, 2005 10:09:21 PM

Archived from groups: rec.photo.digital (More info?)

wavelength wrote:


>
> Another time, I used clone to get rid of 10 houses from a sunset
> landscape, and I could still tell too. I bet someoene looking for it
> would have caught it too. Resized to 50% the effect was un-noticable
> though.
>
> Does that mean that I cant merge photo's to make a landscape and enter
> that? That's silly. I took all of the images.

Yet what you ended up with in print didn't exist in front of the camera.
Those houses where there and there is no place someone could go to actually
view what you "photographed". Even a person standing there next to you
wouldn't have seen when ended up in that image.

Let's say you cloned a shot with Briney Spears at your birthday party, would
you call that a "photograph"?


> George Lucas took the
> wheel of a speeder with vaseline on the lens. That was "cheating".

That's different, when he photographed was actually there in front of the
camera. Using the above example, IF Briney Spears -was- at your birthday
party, smearing vasoline on the lens wouldn't change the fact what you
photographed was actually there in front of the camera.


>Who cares as long as the picture rocks!

Not me but some people do. But I don't care for people doing photo merges
(or cloning out houses/people) and then acting like it's a "photograph". As
long as the person describes it as an "edited digital image" or something
along those lines, anything goes. If you claim it's an "actual photograph"
or something along those lines, no cloning out parts of the image or
merging in something from another.


> People
> buying stock dont car that you airbrushed Gwen Stefani's pimple scars
> out. Why should they care about removing houses and power lines?

What happens when you start cleaning up images is you're presenting a "too
perfect" world. It's like the airbrushed women in magazines, you look at
enough of them and NO woman on the planet will be good enough in 3D. Same
with landscapes, remove all phone lines, trash etc and you've created a
place that doesn't exist.

> But he'd probably be excluded
> from these contests. It's a joke. Art is art.

Actually it's the difference between digital imaging and photography.

--

Stacey
Anonymous
July 31, 2005 12:58:59 AM

Archived from groups: rec.photo.digital (More info?)

No, there is no difference any more.

The guy in the magazine used to sandwich the film together, or do a
multiple exposure. That was still photography because it was "film"
right? What's the differnce now?

The film is 1's an 0's. and the Darkroom is on your computer. It's
still using captured light to create an image.

As for the "too perfect" world syndrome. Maybe you're living in the
"too perfect" and I'm dealing with reality. The idea of perfect and
pristine photographs is seemingly what you want, and maybe I do to.
Guess I'm just a realist, though. Sometimes you have to make lemonade
out of those lemons. Prissy quibbles about "too perfect" be damned. I
make my photographs what I want them to be, IN and OUT of the camera.
Anonymous
July 31, 2005 1:34:44 AM

Archived from groups: rec.photo.digital (More info?)

"Ken Hall" <kenhall2REMOVE@houston.rr.com> wrote in message
news:krjne1dtqppqsvltch0i3a5rlih3ddip97@4ax.com...
> Let me start by saying I do not intend to enter any of these contests,
> much less violate their rules -- I'm just curious as to how they
> enforce them.
>
> It you read the rules for this photo contest website you will see they
> prohibit many image editing techniques.
> http://www.dpchallenge.com/challenge_rules.php
>
> My question is, how do they know? How would they know if I enhanced
> the image using various Photoshop techniques?
>
> For example, "spot editing" is prohibited in one of their contest
> classes. How would they know if I darkened or lightened a selected
> area if it is done so it's not obvious when viewing the image? This
> is but one example of many I can think of.
>
> Ken
Ken,
Most of the online photo contests have some general rules about editing
photos.
The rules are in place so that it will be a photo contest, not an editing or
art (photomanipulation) contest.
The ones that I have entered or checked out all allow what are considered to
be normal photo enhancement, such as cropping, contrast enhancement,
sharpening, or noise reduction.
In other words, the same kinds of adjustments that are ordinarily used in a
regular darkroom to produce a print from a negative should be OK on a
digital photo.
I expect that compliance is mostly voluntary and that no special checking is
performed on the entries.
Any entries that are obviously manipulated would simply be discarded by the
judges.
If you want to experiment on your own I would suggest bringing an editied
photo into Paintshop Pro and splitting the image using each of RGB, CYMK,
and HSL.
Check each layer of the separations for any "fingerprint" in the edited
area, results might be interesting.
You might try smoothing the image, then comparing the result with the
original to look for sharp transitions that are "out of place".
Jack
Anonymous
July 31, 2005 1:41:22 AM

Archived from groups: rec.photo.digital (More info?)

Ken Hall wrote:

> ...
> My question is, how do they know? How would they know if I enhanced
> the image using various Photoshop techniques?
> ...

I think this is an extremely important question but not because
of cheating in photo contests.

The real issues to my mind have to do with manipulation of
the truth. If a prosecutor creates a phony image of evidence
against someone, an innocent man could be convicted. If a
defendant creates a phony image giving him an alibi, a guilty
man could go free.

In the 1930's, Stalin's minions doctored photos from the
revolutionary period to edit Trotsky out of history. Soviet
policy from then on was to alter the record of the past for
present political aims. The same was done in Nazi Germany.

Imagine how easy it would be to do these things today. And
no doubt there are governments that still do them. Let's hope
that our own governments are not among them.

I'm not an expert on this topic. My guess is that very sophisticated
analysis of images is possible to detect color, luminance, line,
shape, volumen, and transition changes that are not likely to
be authentic. But I also guess that very sophisticated cheaters
could produce images that would be very difficult to detect
by these means.

I personally hope the analyzers win and the cheaters lose
this arms race.

Alan

P.S.

Ken,

I recommend you modify the X-no-archive flag in your postings
so that your postings don't disappear from the web. Wouldn't you
rather be known for your actual unedited post than for the excerpts
from your postings that others make? Just as you don't want images
to be doctored, so too why would you want your postings to be
doctored or doctorable - which is what happens when you use
X-no-archive as you have done.
July 31, 2005 4:53:47 AM

Archived from groups: rec.photo.digital (More info?)

"Stacey" <fotocord@yahoo.com> wrote in message
news:3l2c4iF10k0buU1@individual.net...
> wavelength wrote:
>
>
>>
>> Another time, I used clone to get rid of 10 houses from a sunset
>> landscape, and I could still tell too. I bet someoene looking for it
>> would have caught it too. Resized to 50% the effect was un-noticable
>> though.
>>
>> Does that mean that I cant merge photo's to make a landscape and enter
>> that? That's silly. I took all of the images.
>
> Yet what you ended up with in print didn't exist in front of the camera.
> Those houses where there and there is no place someone could go to
> actually
> view what you "photographed". Even a person standing there next to you
> wouldn't have seen when ended up in that image.
>
> Let's say you cloned a shot with Briney Spears at your birthday party,
> would
> you call that a "photograph"?
>
>
>> George Lucas took the
>> wheel of a speeder with vaseline on the lens. That was "cheating".
>
> That's different, when he photographed was actually there in front of the
> camera. Using the above example, IF Briney Spears -was- at your birthday
> party, smearing vasoline on the lens wouldn't change the fact what you
> photographed was actually there in front of the camera.
>
>
>>Who cares as long as the picture rocks!
>
> Not me but some people do. But I don't care for people doing photo merges
> (or cloning out houses/people) and then acting like it's a "photograph".
> As
> long as the person describes it as an "edited digital image" or something
> along those lines, anything goes. If you claim it's an "actual photograph"
> or something along those lines, no cloning out parts of the image or
> merging in something from another.
>
>
>> People
>> buying stock dont car that you airbrushed Gwen Stefani's pimple scars
>> out. Why should they care about removing houses and power lines?
>
> What happens when you start cleaning up images is you're presenting a "too
> perfect" world. It's like the airbrushed women in magazines, you look at
> enough of them and NO woman on the planet will be good enough in 3D. Same
> with landscapes, remove all phone lines, trash etc and you've created a
> place that doesn't exist.
>
>> But he'd probably be excluded
>> from these contests. It's a joke. Art is art.
>
> Actually it's the difference between digital imaging and photography.
>
> --
>
> Stacey



Come on Stacey.

In the days of real real photography, 10 x8 Glass plates, ISO of 5 or
thereabouts, every landscape photographer was fiddling the results.

They had to, their emulsion could not record clouds in the sky. They used
to buy sky images to combine with their landscape.

If the landscape was a bit too empty, they used to do things like draw in
trees, barns or even windmills onto the plate.

Photographers have always "Enhanced" the image one way or another, ever
since photography was invented.

Digital just makes it easier, even for the talentless, and that is probably
the real problem.

Roy G
Anonymous
July 31, 2005 5:39:26 AM

Archived from groups: rec.photo.digital (More info?)

On Sat, 30 Jul 2005 14:17:17 -0500, Ken Hall <kenhall2REMOVE@houston.rr.com> wrote:

>Let me start by saying I do not intend to enter any of these contests,
>much less violate their rules -- I'm just curious as to how they
>enforce them.
>
>It you read the rules for this photo contest website you will see they
>prohibit many image editing techniques.
>http://www.dpchallenge.com/challenge_rules.php
>
>My question is, how do they know? How would they know if I enhanced
>the image using various Photoshop techniques?
>
>For example, "spot editing" is prohibited in one of their contest
>classes. How would they know if I darkened or lightened a selected
>area if it is done so it's not obvious when viewing the image? This
>is but one example of many I can think of.

Printing out a 10x8 will often show signs of editing.
July 31, 2005 6:21:35 AM

Archived from groups: rec.photo.digital (More info?)

wavelength wrote:

> No, there is no difference any more.
>
> The guy in the magazine used to sandwich the film together, or do a
> multiple exposure. That was still photography because it was "film"
> right?

Not to me, YMMV.. I never considered double exposures real photography.


> Prissy quibbles about "too perfect" be damned. I
> make my photographs what I want them to be, IN and OUT of the camera.

Doesn't mean I have to accept them as "photographs".

What's wrong with explaining you -digitally altered- an image when you
display it if you aren't afraid someone would think less of it if they knew
this? Why do you think these contests ask that you don't do this, yet
people are trying to figure out if they'll get caught cloning out or
merging images trying to come up with something interesting? Is it THAT
difficult to capture something interesting without resorting to this?

--

Stacey
July 31, 2005 9:49:23 AM

Archived from groups: rec.photo.digital (More info?)

With the way our current administration lies to the people on a host of
issues, doctoring photos would be second nature to our government.

"Alan Meyer" <ameyer2@yahoo.com> wrote in message
news:1122784882.745617.295870@g44g2000cwa.googlegroups.com...
> Ken Hall wrote:
>
> > ...
> > My question is, how do they know? How would they know if I enhanced
> > the image using various Photoshop techniques?
> > ...
>
> I think this is an extremely important question but not because
> of cheating in photo contests.
>
> The real issues to my mind have to do with manipulation of
> the truth. If a prosecutor creates a phony image of evidence
> against someone, an innocent man could be convicted. If a
> defendant creates a phony image giving him an alibi, a guilty
> man could go free.
>
> In the 1930's, Stalin's minions doctored photos from the
> revolutionary period to edit Trotsky out of history. Soviet
> policy from then on was to alter the record of the past for
> present political aims. The same was done in Nazi Germany.
>
> Imagine how easy it would be to do these things today. And
> no doubt there are governments that still do them. Let's hope
> that our own governments are not among them.
>
> I'm not an expert on this topic. My guess is that very sophisticated
> analysis of images is possible to detect color, luminance, line,
> shape, volumen, and transition changes that are not likely to
> be authentic. But I also guess that very sophisticated cheaters
> could produce images that would be very difficult to detect
> by these means.
>
> I personally hope the analyzers win and the cheaters lose
> this arms race.
>
> Alan
>
> P.S.
>
> Ken,
>
> I recommend you modify the X-no-archive flag in your postings
> so that your postings don't disappear from the web. Wouldn't you
> rather be known for your actual unedited post than for the excerpts
> from your postings that others make? Just as you don't want images
> to be doctored, so too why would you want your postings to be
> doctored or doctorable - which is what happens when you use
> X-no-archive as you have done.
>
Anonymous
July 31, 2005 10:39:44 AM

Archived from groups: rec.photo.digital (More info?)

I guess I don't have a problem telling anyone I edited to get the final
product. I told all of you didn't I ? :0)

Happy Sunday!!
Anonymous
July 31, 2005 12:11:40 PM

Archived from groups: rec.photo.digital (More info?)

In article <g_qdnUgNN9-MhHHfRVn-3g@giganews.com>, Bob Harrington says...

> Might be they just demand an original RAW file / slide / negative from
> the contest winners to compare with the entered image? This would give
> an idea of what changes were made to the entered image, like spot clones
> and levels/color corrections.
>
> Is it practicably possible to edit a RAW file and save it in the same
> RAW format?

Not every photo is shot as RAW.
--

Alfred Molon
------------------------------
Olympus 4040, 5050, 5060, 7070, 8080, E300 forum at
http://groups.yahoo.com/group/MyOlympus/
Olympus E300 resource - http://myolympus.org/E300/
July 31, 2005 1:59:04 PM

Archived from groups: rec.photo.digital (More info?)

"Ken Hall" <kenhall2REMOVE@houston.rr.com> wrote in message
news:krjne1dtqppqsvltch0i3a5rlih3ddip97@4ax.com...
> Let me start by saying I do not intend to enter any of these contests,
> much less violate their rules -- I'm just curious as to how they
> enforce them.
>
> It you read the rules for this photo contest website you will see they
> prohibit many image editing techniques.
> http://www.dpchallenge.com/challenge_rules.php
>
> My question is, how do they know? How would they know if I enhanced
> the image using various Photoshop techniques?
>
> For example, "spot editing" is prohibited in one of their contest
> classes. How would they know if I darkened or lightened a selected
> area if it is done so it's not obvious when viewing the image? This
> is but one example of many I can think of.
>
> Ken


Hi there.

They don't know.

They rely on honesty from the contestants.

The British Press Photographer of the Year Contest used to ask for the
negatives, just before making their awards. I know a number of local Staff
Photographers who lost out, just because the Picture Library of the Paper
had managed to misfile the Negs.

That just added ammunition to the war which was always raging between the
Staff Photographers and the Editorial Staff.

Roy G
July 31, 2005 6:12:40 PM

Archived from groups: rec.photo.digital (More info?)

What about if the modified timestamp on a JPEG was significantly later than
the time the photo was taken (which is stored within the JPEG)? Of course,
its very easy to change the modified timestamp on a file in Windows (any
many OSs).

Mark.

"Ken Hall" <kenhall2REMOVE@houston.rr.com> wrote in message
news:krjne1dtqppqsvltch0i3a5rlih3ddip97@4ax.com...
> Let me start by saying I do not intend to enter any of these contests,
> much less violate their rules -- I'm just curious as to how they
> enforce them.
>
> It you read the rules for this photo contest website you will see they
> prohibit many image editing techniques.
> http://www.dpchallenge.com/challenge_rules.php
>
> My question is, how do they know? How would they know if I enhanced
> the image using various Photoshop techniques?
>
> For example, "spot editing" is prohibited in one of their contest
> classes. How would they know if I darkened or lightened a selected
> area if it is done so it's not obvious when viewing the image? This
> is but one example of many I can think of.
>
> Ken
August 1, 2005 1:05:10 AM

Archived from groups: rec.photo.digital (More info?)

Old Bugger wrote:

>
> Printing out a 10x8 will often show signs of editing.
>
>

err... how?
If it isn't done well perhaps?
Anonymous
August 1, 2005 3:13:09 AM

Archived from groups: rec.photo.digital (More info?)

On Sun, 31 Jul 2005 21:05:10 +1200, frederick <nomail@nomail.com> wrote:

>> Printing out a 10x8 will often show signs of editing.
>>
>>
>
>err... how?
>If it isn't done well perhaps?

If it isn't done pixel by pixel it isn't hard to tell.
Anonymous
August 1, 2005 6:22:31 AM

Archived from groups: rec.photo.digital (More info?)

> Let's hope that our own governments are not among them.
>
TOO LATE
August 1, 2005 6:38:57 AM

Archived from groups: rec.photo.digital (More info?)

Old Bugger wrote:

> On Sun, 31 Jul 2005 21:05:10 +1200, frederick <nomail@nomail.com> wrote:
>
>>> Printing out a 10x8 will often show signs of editing.
>>>
>>>
>>
>>err... how?
>>If it isn't done well perhaps?
>
> If it isn't done pixel by pixel it isn't hard to tell.

Depends on the size of the origial image file. You could edit a 350Mb image
file, print it to 8X10 at 600DPI and I doubt it would be able to be seen.
--

Stacey
Anonymous
August 1, 2005 11:26:31 AM

Archived from groups: rec.photo.digital (More info?)

I doubt anyone is still on this thread. But this is one of the pictures
that I made using the "photomerge" tool in PS-Elements.

http://photos1.blogger.com/img/59/6096/1024/spanish_pea...

I don't see how my merging 5 full size files together to get a shot
that would probably have been impossible for a panoramic lens is
somehow "cheating" or making the world too perfect. This is not the
picture where I removed some houses btw. :) 

I don't know of a panoramic lens that can take a shot at 200mm, and I
probably wouldn't want to pay for it. My in-laws live there, and they
have never seen a shot quite like it.

I you've ever used photomerge, you should know that it takes at least a
little bit of talent to get a picture to come out evenly exposed across
5 frames.

Again, I'll point to the fact that I got the Idea from a Pro in a photo
magazine who took a shot of a bunch of birds sitting on a log at 400mm,
evenly exposed them, and merged them in post-processing to get a
publishable photograph.

If he can do it and be famous for it. I don't see how it makes an
amatuer a "cheat". But again, by the rules of many of these contests,
this shot, and his shot are taboo.
Anonymous
August 1, 2005 1:57:03 PM

Archived from groups: rec.photo.digital (More info?)

>Ken Hall writes ...
>
>It you read the rules for this photo contest website you will see
>they prohibit many image editing techniques ...
>My question is, how do they know? How would they know if I
>enhanced the image using various Photoshop techniques?

I entered a contest recently where they accept jpegs on a CD or dupe
slides for the initial screening, but if you win you have to supply the
original slide or the original RAW file to gurarantee there was no
manipulation (they allowed tonal corrections but nothing else). So for
their purposes you can just supply a digital RAW file, which is proof
enough for a contest.

For things like evidence in court Canon sells a security kit with the
1D and 1Ds series cameras that basically guarantees at the pixel level
that the file is unchanged from the original, but for contests this
level of guarantee isn't necessary.

Bill
Anonymous
August 1, 2005 1:59:17 PM

Archived from groups: rec.photo.digital (More info?)

> Alfred Molon writes ...
>
>Not every photo is shot as RAW.

Most of the prestigious contests I'm aware of (Nature's Best contest,
BBC/Mobil Gas Wildlife Photographer of the Year contest) require you to
shoot in RAW or with slide film, so jpegs or print films are not
eligible.
Anonymous
August 1, 2005 2:22:34 PM

Archived from groups: rec.photo.digital (More info?)

>Alan Meyer writes ...
>
>I think this is an extremely important question but not because
>of cheating in photo contests.

I agree.

>The real issues to my mind have to do with manipulation of
>the truth. If a prosecutor creates a phony image of evidence
>against someone, an innocent man could be convicted. If a
>defendant creates a phony image giving him an alibi, a guilty
>man could go free.

Here is a link to Canon's solution for law enforcement and courts,
guaranteeing the image is not modified after the original capture ...
http://www.dpreview.com/news/0401/04012903canondvke2.as...

Bill
Anonymous
August 1, 2005 5:31:02 PM

Archived from groups: rec.photo.digital (More info?)

> Zed Pobre writes ...
>
>If it's some form of public key signing technique, then the key has
>to be unique to the camera

Yes, it's unique to each camera ... did you read the link?

>Either way, until the algorithm and design are publically known
>and reviewed, it shouldn't be trusted.

Industry standards are usually defined by committees on the
International Standards Organization or American Standards Association
(ISO or ASA), sometimes ANSI (American National Standards Institute, I
think). They define what is required, issue papers describing the spec
and define tests to show that the product meets that spec. Apparently
Canon has submitted this data verification kit for "ISO 15408
certification" to meet this criteria. You can probably read up on the
spec requirements somewhere to see what the spec encompasses.

Bill
Anonymous
August 1, 2005 7:58:57 PM

Archived from groups: rec.photo.digital (More info?)

>>> Zed Pobre writes
>>>If it's some form of public key signing technique, then the key
>>>has to be unique to the camera

>>Bill wrote
>> Yes, it's unique to each camera ... did you read the link?

> Zed Pobre writes
>I did. Did you?

Yes and the first sentence says "...the DVK-E2 kit is designed to
deliver validation of an unmodified original image from a single camera
body."

I'm interpreting "single camera body" to mean "unique to each camera",
right?

> ... there are a lot of ways to do digital signing wrong

The simple, straight-forward way to prove that Canon has done the
encryption wrong is to shoot an image using this kit, modify the image
and rewrite as a RAW file and then pass it off as unmodified when
'verified' by the kit. If you can do that then you will prove Canon is
wrong. Do you have any links showing that this has been done by
*anyone*? Didn't think so ...

Bill
Anonymous
August 1, 2005 11:33:38 PM

Archived from groups: rec.photo.digital (More info?)

Bill Hilton wrote:
> ...
> The simple, straight-forward way to prove that Canon has done the
> encryption wrong is to shoot an image using this kit, modify the image
> and rewrite as a RAW file and then pass it off as unmodified when
> 'verified' by the kit. If you can do that then you will prove Canon is
> wrong. Do you have any links showing that this has been done by
> *anyone*? Didn't think so ...
> ...

I have to agree with Zed on this one.

There's no doubt that _I_ am not able to pass off as unmodified
one of these Canon images. What I worry about is whether there
are experts who could do it.

The various "authorities" in every advanced country have access
to cryptography experts whose job it is to break encryption
schemes. If somebody sells an encryption scheme that the general
public can't break, but the experts can, then we have the worst
of all possible worlds - modifiable images that the public
accepts as unmodifiable. If, for example, the CIA were to fabricate
photographic evidence of weapons of mass destruction in Iraq (I'm
not saying they would mind you), and if in addition they were
able to certify those fabrications using technology that we all
thought was tamper proof, no one could challenge them.

Recent history is littered with "unbreakable" codes that were,
in fact, broken. Right now, our best defense against code
breakers is public algorithms. If an algorithm is public and
can be tested by anyone, and it still holds up, then it is much
less likely (though still not impossible!) that the secret code
breakers will solve it.

Alan
Anonymous
August 2, 2005 12:17:04 AM

Archived from groups: rec.photo.digital (More info?)

Bill Hilton <bhilton665@aol.com> wrote:
>
>>Alan Meyer writes ...
>>
>>I think this is an extremely important question but not because
>>of cheating in photo contests.
>
> I agree.
>
>>The real issues to my mind have to do with manipulation of
>>the truth. If a prosecutor creates a phony image of evidence
>>against someone, an innocent man could be convicted. If a
>>defendant creates a phony image giving him an alibi, a guilty
>>man could go free.
>
> Here is a link to Canon's solution for law enforcement and courts,
> guaranteeing the image is not modified after the original capture ...
> http://www.dpreview.com/news/0401/04012903canondvke2.as...

Without a better public examination of how that tool works, I hope
that no courts accept it. If all that amounts to is a proprietary
hash generated in the camera, checked against an algorithm provided by
proprietary Windows code, then all it takes to falsify an image is to
reverse-engineer the algorithm.

If it's some form of public key signing technique, then the key has to
be unique to the camera and unextractable by analysis of the
components.

Either way, until the algorithm and design are publically known and
reviewed, it shouldn't be trusted.

--
Zed Pobre <zed@resonant.org> a.k.a. Zed Pobre <zed@debian.org>
PGP key and fingerprint available on finger; encrypted mail welcomed.
August 2, 2005 1:27:23 AM

Archived from groups: rec.photo.digital (More info?)

Old Bugger wrote:

> On Sun, 31 Jul 2005 21:05:10 +1200, frederick <nomail@nomail.com> wrote:
>
>
>>>Printing out a 10x8 will often show signs of editing.
>>>
>>>
>>
>>err... how?
>>If it isn't done well perhaps?
>
>
> If it isn't done pixel by pixel it isn't hard to tell.
>
>
I don't know about that. I just printed a 19 x 13 from a 4500 x 3000
file, I cloned a out few blemishes with a soft edge brush, and I can't
see them in the print at all. Tweaking view display filters might draw
your eye to areas worth closer inspection. Depends what you mean by
editing - I still doubt that my cloning would show, but a missing
building or other recognisable shape might be easy to spot.
Anonymous
August 2, 2005 1:31:07 AM

Archived from groups: rec.photo.digital (More info?)

Bill Hilton wrote:
>>Alfred Molon writes ...
>>
>>Not every photo is shot as RAW.
>
>
> Most of the prestigious contests I'm aware of (Nature's Best contest,
> BBC/Mobil Gas Wildlife Photographer of the Year contest) require you to
> shoot in RAW or with slide film, so jpegs or print films are not
> eligible.
>

Hi Bill,
The Nature's Best contest this year did seem more specific about
raw files. But my egret in flight winner in last year's Nature's Best
was a jpeg. I did submit jpegs this year too. I interpreted raw
to mean the original unmodified file. We'll see....
They did not mind last year.

Personally, some contest's definitions of modifications would
preclude an Ansel Adam's print from ever being entered, and I think
such rules are extreme. Contrast adjustment, dodging, burning
and cloning out dust and scratches, and smoothing noise
should all be allowed in my opinion. That is what is needed to
compress the dynamic range for printing.

Regarding detection of editing, especially smaller things can often
be found (sometimes) by stretching the image hard at various levels
and running unsharp mask and other tools with extreme settings.
Often cloning residuals show up in such tests, especially in shadow
areas. Shadows and shading often are giveaways to wrong lighting
and show something has been added. Adding the full moon to a landscape
image with strong shadows is often done. I recently pointed out
to a gallery owner an obviously fake photo in his gallery
of a full moon through heavily shadowed Delicate Arch in Arches
National Park by a very famous photographer. An impossible shot.
Few people, even photographers seem to understand the subtleties
of lighting, so they often make such mistakes.

Roger
Anonymous
August 2, 2005 1:46:19 AM

Archived from groups: rec.photo.digital (More info?)

Zed Pobre wrote:

> Either way, until the algorithm and design are publically known and
> reviewed, it shouldn't be trusted.
>

Bill, you are getting beat up a little here, but there really
is cause for concern. I recently was stunned to learn that
hackers are so good, they can break into a computer system,
leave trap doors and patch programs such that files sizes,
checksums, and tripwires are unaffected. Remember, if you
have 8 million pixels at 12 bits/pixel, you really need
close to 12 million bytes to describe it perfectly. Anything
less is an approximation. Same with cryptography. Just how
secure is a matter of compute power and time. The fact that
the company is coming out with version 2 might be an indication
of flaws in version 1. How do we know version 2 is good enough?

In courts, photographs have been used as evidence for decades,
and photographs could be faked for that whole time. Courts
require statements from the photographer as to authenticity.
....Probably still will even with this new technology.

Roger
Anonymous
August 2, 2005 2:17:05 AM

Archived from groups: rec.photo.digital (More info?)

Bill Hilton <bhilton665@aol.com> wrote:
>
>> Zed Pobre writes ...
>>
>>If it's some form of public key signing technique, then the key has
>>to be unique to the camera
>
> Yes, it's unique to each camera ... did you read the link?

I did. Did you? Nowhere in the link does it talk about keys, or even
algorithms.

"The kit consists of a dedicated SM (secure mobile) card reader/writer
and verification software. When the appropriate function (Personal
Function 31) on the EOS-1D Mark II or EOS-1Ds is activated, a code
based on the image contents is generated and appended 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 image contents have been manipulated in any way, the
codes will not match and the image cannot be verified as the
original."

That process could describe 'md5sum img_0001.cr2', and a second black
box that runs 'md5sum img_0001.cr2' and compares the two numbers,
which is absolutely useless for fraud protection. You can be generous
and say that it's probably a better system than that, but there are a
lot of ways to do digital signing wrong (insufficient key length,
insufficient protection of the signing key, weak signing algorithm,
incorrect implementation of signing algorithm, etc.). Don't trust
black box crypto. Don't trust the judgement of anyone who does.


>>Either way, until the algorithm and design are publically known
>>and reviewed, it shouldn't be trusted.
>
> Industry standards are usually defined by committees on the
> International Standards Organization or American Standards Association
> (ISO or ASA), sometimes ANSI (American National Standards Institute, I
> think). They define what is required, issue papers describing the spec
> and define tests to show that the product meets that spec. Apparently
> Canon has submitted this data verification kit for "ISO 15408
> certification" to meet this criteria. You can probably read up on the
> spec requirements somewhere to see what the spec encompasses.

Er, no, unless I'm misremembering badly, the ISO 15408 certs cover a
pretty wide range of things, and are based very heavily on exactly how
the submitter claims the product to be tested will always be used and
in what environment. It also is, to the best of my knowledge, a
confidential process. You submit your product for evaluation to a
certified testing lab, and get certified or not. Your techniques
never get opened up to public review, so the even a certified device
is still nothing better than a black box that an "expert" somewhere
examined, against undisclosed assumptions, to see if the product was
compliant with those assumptions.

If you have an absolute faith in the incorruptibility of all members
of all testing labs, and an absolute faith in how appropriate the
submission description was to actual real use, it's fine. I
personally treat ISO 15408 testing as a means for one large
organization to get another large organization to say "Of course it's
safe... trust me. We're perfectly trustworthy. No, you can't
check."

If you want to pull down a toolkit to see for yourself, you can order
one from the ISO 15408 group for $200.

--
Zed Pobre <zed@resonant.org> a.k.a. Zed Pobre <zed@debian.org>
PGP key and fingerprint available on finger; encrypted mail welcomed.
Anonymous
August 2, 2005 2:23:09 AM

Archived from groups: rec.photo.digital (More info?)

On 1 Aug 2005 13:31:02 -0700, Bill Hilton wrote:
>> Zed Pobre writes ...
>>
>>If it's some form of public key signing technique, then the key has
>>to be unique to the camera
>
> Yes, it's unique to each camera ... did you read the link?
>
>>Either way, until the algorithm and design are publically known
>>and reviewed, it shouldn't be trusted.
>
> Industry standards are usually defined by committees on the
> International Standards Organization or American Standards Association
> (ISO or ASA), sometimes ANSI (American National Standards Institute, I
> think).

And, then, implementers roll out "New And Improved" -.a, -.b, -.c, -.g,
etc., versions of the 'standard' and chaos continues unabated.

"Standards are great! And, there are so *many* to choose from!"
unknown (-by me.)

Jonesy
--
Marvin L Jones | jonz | W3DHJ | linux
Pueblo, Colorado | @ | Jonesy | OS/2 __
38.24N 104.55W | config.com | DM78rf | SK
Anonymous
August 2, 2005 11:30:15 AM

Archived from groups: rec.photo.digital (More info?)

On Mon, 01 Aug 2005 22:17:05 GMT, Zed Pobre <zed@resonant.org> wrote:

>Bill Hilton <bhilton665@aol.com> wrote:
>>
>>> Zed Pobre writes ...
>>>
>>>If it's some form of public key signing technique, then the key has
>>>to be unique to the camera
>>
>> Yes, it's unique to each camera ... did you read the link?
>
>I did. Did you? Nowhere in the link does it talk about keys, or even
>algorithms.
>
>"The kit consists of a dedicated SM (secure mobile) card reader/writer
>and verification software. When the appropriate function (Personal
>Function 31) on the EOS-1D Mark II or EOS-1Ds is activated, a code
>based on the image contents is generated and appended 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 image contents have been manipulated in any way, the
>codes will not match and the image cannot be verified as the
>original."
>
>That process could describe 'md5sum img_0001.cr2', and a second black
>box that runs 'md5sum img_0001.cr2' and compares the two numbers,
>which is absolutely useless for fraud protection. You can be generous
>and say that it's probably a better system than that, but there are a
>lot of ways to do digital signing wrong (insufficient key length,
>insufficient protection of the signing key, weak signing algorithm,
>incorrect implementation of signing algorithm, etc.). Don't trust
>black box crypto. Don't trust the judgement of anyone who does.
>
>
>>>Either way, until the algorithm and design are publically known
>>>and reviewed, it shouldn't be trusted.
>>
>> Industry standards are usually defined by committees on the
>> International Standards Organization or American Standards Association
>> (ISO or ASA), sometimes ANSI (American National Standards Institute, I
>> think). They define what is required, issue papers describing the spec
>> and define tests to show that the product meets that spec. Apparently
>> Canon has submitted this data verification kit for "ISO 15408
>> certification" to meet this criteria. You can probably read up on the
>> spec requirements somewhere to see what the spec encompasses.
>
>Er, no, unless I'm misremembering badly, the ISO 15408 certs cover a
>pretty wide range of things, and are based very heavily on exactly how
>the submitter claims the product to be tested will always be used and
>in what environment. It also is, to the best of my knowledge, a
>confidential process. You submit your product for evaluation to a
>certified testing lab, and get certified or not. Your techniques
>never get opened up to public review, so the even a certified device
>is still nothing better than a black box that an "expert" somewhere
>examined, against undisclosed assumptions, to see if the product was
>compliant with those assumptions.
>
>If you have an absolute faith in the incorruptibility of all members
>of all testing labs, and an absolute faith in how appropriate the
>submission description was to actual real use, it's fine. I
>personally treat ISO 15408 testing as a means for one large
>organization to get another large organization to say "Of course it's
>safe... trust me. We're perfectly trustworthy. No, you can't
>check."
>
>If you want to pull down a toolkit to see for yourself, you can order
>one from the ISO 15408 group for $200.


Excellent post.

Joe C.
Anonymous
August 2, 2005 11:31:58 AM

Archived from groups: rec.photo.digital (More info?)

>Roger Clark writes ...
>
>Bill, you are getting beat up a little here ...

I thought I was winning on points ... :) 

>Same with cryptography. Just how
>secure is a matter of compute power and time.

I only worked on one crypto chip in my designer days and I didn't delve
into the guts because I was the project manager (and didn't want to
sign the NDA for other reasons), but the crack for the code we did (in
a small chip) was supposedly several years for a dedicated
super-computer. Typically this would allow you to just read the
encrypted message. For something like an image you'd not only have to
read the code but be able to create a 'fake' image that's optically
believable, re-encrypt it and have it accepted at the other end. This
seems harder to me than just breaking the code to read it.

At any rate Canon is pitching this for law enforcement and courtrooms
(insurance lawsuits) and I doubt most police departments will have
access to years of supercomputer time which they'd use just to tinker
with evidence.

>The fact that the company is coming out with version 2
>might be an indication of flaws in version 1.

A less paranoid view is that there are two reasons for version 2 ... 1)
they added support for three new cameras and 2) they switched to a
Secure Mobile (SM) card reader to make the system lighter and cheaper.
Not as sexy a theory as "might be an indication of flaws" but it makes
more sense to me.

>How do we know version 2 is good enough?

You'll know if either V1 or V2 is not "good enough" once people are
able to crack it and have faked photos 'verified' as authentic. So far
this hasn't happened, as far as I know (Zed is probably off researching
this right now).

>In courts, photographs have been used as evidence for decades,
>and photographs could be faked for that whole time.

Right, and it was easier to fake those than to outwit the Canon data
verification kit, wouldn't you agree?

>Courts require statements from the photographer as to
>authenticity.

Like the guy who swore he had a valid model release from Cameron Diaz
for the topless shots? Photographers would never lie :) 

Bill
Anonymous
August 2, 2005 6:32:26 PM

Archived from groups: rec.photo.digital (More info?)

On Sat, 30 Jul 2005 14:17:17 -0500, Ken Hall wrote:

> It you read the rules for this photo contest website you will see they
> prohibit many image editing techniques.
> http://www.dpchallenge.com/challenge_rules.php

This is what pisses me off about contests now.

If I do a little dodge/burn and a crop on a digital image in PhotoShop I
have to declare this and have it marked against the picture.

However if I took the photograph on film and did exactly the same in a wet
darkroom, I wouldn't need to even bother mentioning it.

OK, it *is* far easier to do edits in PhotoShop, but that does not mean you
can *not* edit film. Double standards if you ask me.

-SL
August 3, 2005 5:06:42 AM

Archived from groups: rec.photo.digital (More info?)

Roger N. Clark (change username to rnclark) wrote:


>
> In courts, photographs have been used as evidence for decades,
> and photographs could be faked for that whole time. Courts
> require statements from the photographer as to authenticity.
> ...Probably still will even with this new technology.
>


I presented some images taken with a nikon 2MP P&S in a recent court case
and no one questioned if the images were edited but I had to testify that I
took these photographs and they were pictures of the actual parts off a
persons car. We won the case so the judge obviously accepted these as "real
photographs" even though they were taken with a digicam, so the
photographers testimony seems to be what they care about?

--

Stacey
August 3, 2005 5:10:00 AM

Archived from groups: rec.photo.digital (More info?)

Bill Hilton wrote:

>>Roger Clark writes ...

>
> At any rate Canon is pitching this for law enforcement and courtrooms
> (insurance lawsuits) and I doubt most police departments will have
> access to years of supercomputer time which they'd use just to tinker
> with evidence.

In my experience, they listen to the testimony of the photographer more than
anything. -Maybe- this encription could be used if the person presenting
the photographs wasn't the actual person who took the pictures or was of
questionable character?



--

Stacey
August 3, 2005 5:13:38 AM

Archived from groups: rec.photo.digital (More info?)

Roger N. Clark (change username to rnclark) wrote:


>
> Personally, some contest's definitions of modifications would
> preclude an Ansel Adam's print from ever being entered, and I think
> such rules are extreme. Contrast adjustment, dodging, burning
> and cloning out dust and scratches, and smoothing noise
> should all be allowed in my opinion. That is what is needed to
> compress the dynamic range for printing.

Exactly. I think it's silly to go this "overboard" on digital images. Then
again I've seen contests where there can be NO cropping and you must show
the film rebate. If you don't like a certain type of contest, don't
compete!



--

Stacey
Anonymous
August 3, 2005 11:02:42 AM

Archived from groups: rec.photo.digital (More info?)

On Wed, 03 Aug 2005 01:10:00 -0400, Stacey <fotocord@yahoo.com> wrote:

>In my experience, they listen to the testimony of the photographer more than
>anything. -Maybe- this encription could be used if the person presenting
>the photographs wasn't the actual person who took the pictures or was of
>questionable character?

Why not both? Trust and Verify

Ken
Anonymous
August 3, 2005 3:15:09 PM

Archived from groups: rec.photo.digital (More info?)

Stacey wrote:
> Roger N. Clark (change username to rnclark) wrote:
>
>>In courts, photographs have been used as evidence for decades,
>>and photographs could be faked for that whole time. Courts
>>require statements from the photographer as to authenticity.
>>...Probably still will even with this new technology.
>
> I presented some images taken with a nikon 2MP P&S in a recent court case
> and no one questioned if the images were edited but I had to testify that I
> took these photographs and they were pictures of the actual parts off a
> persons car.

Your testimony was key.

> We won the case so the judge obviously accepted these as "real
> photographs" even though they were taken with a digicam, so the
> photographers testimony seems to be what they care about?
>

If the bulk of the case rested on photographs- unlikely- then *that*
judge accepted them, probably based on your testimony, and the fact that
the source was digital was possibly wholly irrelevant.

I believe it remains to be seen if there's a consensus on court's
accepting digital photos based on verification schemes. Testimony of
responsible photographers should hold up.

--
John McWilliams

Two vultures board an airplane, each carrying two dead raccoons. The
flight attendant looks at them and says, "I'm sorry, gentlemen, only one
carrion allowed per passenger."
Anonymous
August 3, 2005 3:45:22 PM

Archived from groups: rec.photo.digital (More info?)

"John McWilliams" <jpmcw@comcast.net> wrote in message
news:4pydnf8U64kslGzfRVn-vw@comcast.com...
> Stacey wrote:
> > Roger N. Clark (change username to rnclark) wrote:
> >
> >>In courts, photographs have been used as evidence for decades,
> >>and photographs could be faked for that whole time. Courts
> >>require statements from the photographer as to authenticity.
> >>...Probably still will even with this new technology.
> >
> > I presented some images taken with a nikon 2MP P&S in a recent court
case
> > and no one questioned if the images were edited but I had to testify
that I
> > took these photographs and they were pictures of the actual parts off a
> > persons car.
>
> Your testimony was key.
>
> > We won the case so the judge obviously accepted these as "real
> > photographs" even though they were taken with a digicam, so the
> > photographers testimony seems to be what they care about?
> >
>
> If the bulk of the case rested on photographs- unlikely- then *that*
> judge accepted them, probably based on your testimony, and the fact that
> the source was digital was possibly wholly irrelevant.
>
> I believe it remains to be seen if there's a consensus on court's
> accepting digital photos based on verification schemes. Testimony of
> responsible photographers should hold up.

All evidence must be authenticated before it will be admitted. Digital
photographs are treated no differently than any other form of evidence.
They can be authenticated by the photographer, but also by a percipient
witness, e.g. "I'm going to show you some photographs. Do these accurately
depict what you observed that day?" "Yes, they do."

I once had opposing counsel object to some digital photographs on the ground
that they had been manipulated (they hadn't). The judge overruled the
objection on the ground that (1) I had properly authenticated the
photographs (through a percipient witness, but not the photographer) and (2)
opposing counsel wasn't an expert witness and couldn't offer testimony on
the supposed manipulation.


>
> --
> John McWilliams
>
> Two vultures board an airplane, each carrying two dead raccoons. The
> flight attendant looks at them and says, "I'm sorry, gentlemen, only one
> carrion allowed per passenger."
August 4, 2005 6:34:00 AM

Archived from groups: rec.photo.digital (More info?)

John McWilliams wrote:

> Stacey wrote:
>> We won the case so the judge obviously accepted these as "real
>> photographs" even though they were taken with a digicam, so the
>> photographers testimony seems to be what they care about?
>>
>
> If the bulk of the case rested on photographs- unlikely- then *that*
> judge accepted them, probably based on your testimony, and the fact that
> the source was digital was possibly wholly irrelevant.

It was what tipped the case in our favor. When the Judge gave her ruling she
said "What really bothers me is what I see in these photographs". I believe
without showing this evidence, we would have lost. I think the fact they
were digital didn't even come into it.



--

Stacey
Anonymous
August 4, 2005 8:17:03 PM

Archived from groups: rec.photo.digital (More info?)

Stacey <fotocord@yahoo.com> wrote:
>
> John McWilliams wrote:
>
>> Stacey wrote:
>>> We won the case so the judge obviously accepted these as "real
>>> photographs" even though they were taken with a digicam, so the
>>> photographers testimony seems to be what they care about?
>>
>> If the bulk of the case rested on photographs- unlikely- then *that*
>> judge accepted them, probably based on your testimony, and the fact that
>> the source was digital was possibly wholly irrelevant.
>
> It was what tipped the case in our favor. When the Judge gave her ruling she
> said "What really bothers me is what I see in these photographs". I believe
> without showing this evidence, we would have lost. I think the fact they
> were digital didn't even come into it.

I actually don't have a problem with the court resting a finding on
its perception of the integrity of a photographer; society has long
accepted a back and forth on the trustworthiness of an individual. I
get very worried when I see courts resting a finding on the result of
a technological tool that nobody in the room has ever seen the
workings of, particularly since technology has a long history of
breaking down, particularly when someone *wants* it to break down.
There was already a case in Florida where lots of extra evidence was
ignored in favor of a fingerprint match... and someone went to jail
on what was later determined to be police sloppiness double-checking a
technological failure.

What I worry about in this case is that we'll eventually have a
situation where a police department breaks a signing key and forges
photographic evidence on someone they're *sure* is guilty but isn't
(we'll even disregard the cases of where they simply want someone they
know is innocent to be punished for something unrelated), and then
when conflicting evidence comes out, it will be discarded because the
Canon kit claims the photograph is unaltered, so everyone assumes it
must be unaltered, despite the fact that no independent agent of the
court knows how that device works or how secure it is.

It's a bit like convicting someone on the strength of unproven science
published in a non-peer-reviewed, non-public journal.

--
Zed Pobre <zed@resonant.org> a.k.a. Zed Pobre <zed@debian.org>
PGP key and fingerprint available on finger; encrypted mail welcomed.
August 5, 2005 6:12:50 AM

Archived from groups: rec.photo.digital (More info?)

Zed Pobre wrote:

>
> What I worry about in this case is that we'll eventually have a
> situation where a police department breaks a signing key and forges
> photographic evidence on someone they're *sure* is guilty but isn't
>

Or vice versa. Hacking something like this would easily be posible if enough
money was at stake! I don't like it either.
--

Stacey
August 5, 2005 12:14:40 PM

Archived from groups: rec.photo.digital (More info?)

Stacey wrote:
> John McWilliams wrote:
>
>
>>Stacey wrote:
>>
>>>We won the case so the judge obviously accepted these as "real
>>>photographs" even though they were taken with a digicam, so the
>>>photographers testimony seems to be what they care about?
>>>
>>
>>If the bulk of the case rested on photographs- unlikely- then *that*
>>judge accepted them, probably based on your testimony, and the fact that
>>the source was digital was possibly wholly irrelevant.
>
>
> It was what tipped the case in our favor. When the Judge gave her ruling she
> said "What really bothers me is what I see in these photographs". I believe
> without showing this evidence, we would have lost. I think the fact they
> were digital didn't even come into it.
>
>
>


Was there no reasonable expectation you of having ulterior motives to
alter the evidence? If not, then your testament regarding the validity
of those images should be allowed to stand as presented.

--
jer
email reply - I am not a 'ten'
!