Creating a very simple revision system for photos in python

[Tim Golden]

On 11/03/2011 16:05, Chris Hulan wrote:
> On Mar 11, 9:56 am, Thomas W<thomas.weh... at gmail.com>  wrote:
>> I`m thinking about creating a very simple revision system for photos
>> in python, something like bazaar, mercurial or git, but for photos.
>> The problem is that handling large binary files compared to plain text
>> files are quite different. Has anybody done something like this or
>> have any thoughts about it, I`d be very grateful. If something like
>> mercurial or git could be used and/or extended/customized that would
>> be even better.
>>
>> We are talking about large numbers of photos and some of them are
>> large in size as well, but the functionality does not have to be a
>> full fledged revision system, just handle checking out, checking in,
>> handling conflicts, rollbacks etc, preferrably without storing
>> complete copies of the files in question for every operation.
>>
>> Thanks for any input. :-)
>
> Most traditional revision systems excel at managing text, but suck at
> binary.
> I recall that Picassa has a revision system
>
> It occurs to me you could use Uuencoding to make binaries more
> amendable to
> handling by text-oriented revision systems

I'm not sure there's much point in doing that. Certainly Subversion,
and I imagine the other main RCS, handle binary data perfectly well;
I mean, they don't stop when they come across a NUL byte or anything
like that. You can't do much with the result except retrieve it, but
I'm not sure that uuencodeing (or any other encoding) adds anything
there, either.

FWIW TortoiseSvn offers an image-diff utility which superimposes the
two versions of an image with an alpha blend (if that's what it's
called). It's basically the electronic equivalent of holding two
sheets of paper up to the light. Don't know if this helps the OP,
mind you.

TJG