internally signed JPEG files
Sascha René Leib
sascha.leib at web.de
Sun Apr 13 15:27:03 CEST 2003
sorry if this has been discussed here already, I am new to this list,
but before I spend my weekend coding I rather ask if somebody has
already done this before.. :-)
I am planning to add a GPG/PGP signature to a JPEG file. However, the
usual procedure of posting a hash key with the file does not appear
very user-friendly to me, that's why I would rather like to go another
way. In short:
- create a signature for the JPEG-Data stream
- insert this signature in a new marker segment in the JPEG file.
Since JPEG viewers should ignore unknown marker segments, this should
not affect average end-users who can still view them conveniently in
their web browsers, etc. For interested viewers, it should be easy to
verify the origin and integrity of the file using a yet-to-write tool,
or potentially even browser plugins.
Do you know if anyone has already taken some efforts into this
direction, or do you know anything I ought to know?
PS: of course, the same should also work with other "tagged" file
formats, e.g. from the IFF-family (TIFF, ILBM, AIFF,...)
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