[KimDaBa] new feature: IPTC keywords

[Marco Molteni]

On Sun, 23 Oct 2005 15:11:16 -0400
Robert L Krawitz <rlk at alum.mit.edu> wrote:

[..]

>    From an IPTC point of view, the keywords must stay in the image
>    since the beginning, without the need of an export phase. Otherwise
>    the potographer would have to remember that he cannot upload photos
>    directly but that he has to export them before.
> 
> BTW, how does this interact with the new Canon cameras that can verify
> that a photo is not modified (presumably using a cryptographic
> checksum or the like)?

I don't know, I wasn't aware of this feature.

But I don't see a problem: keywords, be it jpeg or iptc, are stored
in a specific area of the file, so it is always possible to go back
to the file image without keywords.

But it is amazing, since I always though about something similar.
Too bad Canon beated me to it ;-)

My idea was: how to go back to a unique property of film as opposed
to digital: the fact that if you don't trust a print you can analyze
the negative to see if there are modifications (putting aside the fact
that a negative too can be modified).

I though that the only way was for the camera to store a list of serial
numbers and associated message digest (say MD5 or SHA or whatever).

But then I hit a block because the question is: how do you trust the
list that comes out of the camera? Did Canon solved this?