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On 18/09/2012 22:31, Alan Browne wrote:
> http://bits.blogs.nytimes.com/2012/0...e-marketplace/
>
>
> or http://tinyurl.com/8g8udyp
>
> and http://vimeo.com/49199110 (arguments aren't that convincing)
>
> (It's only $890. Probably more in NZ... )

Any digital faker worth their salt will get all the original camera
image details that the program says it checks exactly right. Unless it
does something else that is undocumented in their press release it isn't
likely to do much more than catch cack handed Photoshop amateurs.

--
Regards,
Martin Brown

In article <>,
Alan Browne <> wrote:
>On 2012.09.18 18:17 , Martin Brown wrote:
>> On 18/09/2012 22:31, Alan Browne wrote:
>>>
>http://bits.blogs.nytimes.com/2012/0...e-marketplace/
>>>
>>>
>>>
>>> or http://tinyurl.com/8g8udyp
>>>
>>> and http://vimeo.com/49199110 (arguments aren't that convincing)
>>>
>>> (It's only $890. Probably more in NZ... )
>>
>> Any digital faker worth their salt will get all the original camera
>> image details that the program says it checks exactly right. Unless it
>> does something else that is undocumented in their press release it isn't
>> likely to do much more than catch cack handed Photoshop amateurs.
>
> From the video it's clear to me that it's purpose is mostly to raise
>doubt (or avoid it). _any_ amount of _any_ change will be detected by
>that program because of the way it analyzes. That does not mean to say
>it proves that the content of the image is faked. Just not camera original.
>
>Even if one were to resize (in PS) and then bring that file to court,
>that program will flag it. That's fine. If the defense want to see the
>camera original then that program can validate it. And that may be
>enough for that purpose.

It should be possible to build a circuit into the sensor chip that
digitally "signs" each image. If the production facility could be
trusted to randomly generate the private keys and delete them after
burning them into each chip, there should be no way short of chip
surgery to generate correctly signed digital images that do not
derive from something "seen" by that sensor. The sensor could be
considered a sort of "trustworthy witness." Unfortunately,

1) You could always contrive a way to show the sensor a scene generated
by other means

2) A friend who works in the industry assures me that the required level
of chip surgery does exist. Still, it should out of reach for a
typical sleazy divorce case. And when it comes to something like
topless pictures of princess Kate, are people going to insist on
seeing the digitally signed RAW camera files before they get all
excited?

--
"Remember when teachers, public employees, Planned Parenthood, NPR and PBS
crashed the stock market, wiped out half of our 401Ks, took trillions in
TARP money, spilled oil in the Gulf of Mexico, gave themselves billions in
bonuses, and paid no taxes? Yeah, me neither."

In article <k3avme$fo8$>, Paul Ciszek
<> wrote:

> It should be possible to build a circuit into the sensor chip that
> digitally "signs" each image.

it's been done:
<http://www.canon.co.jp/imaging/osk/osk-e3/index.html>

and it's been hacked:
<http://www.elcomsoft.com/canon.html>

other versions:
<http://cpn.canon-europe.com/content/...age_verificati
on/canon_data_verification_system.do>

<http://www.dpreview.com/news/2004/1/29/canondvke2>