This is an example of a before and an after image of an illustration of a camera obscura from a seventeenth century manuscript that was restored by Durova. The original is from the Library of Congress, and they are a truly magnificent resource because they provide best quality tiff scans and this allows for quality restorations.
Best practice has it, that when you restore a picture you provide both the original and the restored version. This allows other people to have their go at a restoration if they think they can do better then a Wikipedia featured picture. The problem is that they cannot.
They cannot because as a collaborative platform for restoring images MediaWiki sucks. MediaWiki does not allow people to save tiff files and this is really sad because there is a fledgling community of people restoring all kinds of files. As best practice has it, the original file and the restoration are saved but in a compressed format and consequently, the files do not qualify as the basis to get an even better result.
With the great cooperation with organisations like the Bundesarchiv, we are in a great position to entice archives to provide us on request with full size original scans that need to be restored. We would restore these images to their former glory and everybody is a winner.
It is beyond a doubt that the restoration work done by our volunteers looks smashing. But to impress the people from archives, the technical quality has to be as good. Restorations that are compressed just do not cut it.
Providing tiff support in MediaWiki improves the appreciation of the restoration work and, it makes MediaWiki a platform that can be used by the people who collaborate on these restorations.
Thanks,
GerardM
8 comments:
Can't PNG replace TIFF for this purpose?
Nice blog...
TIFF is considered the gold standard by many people who restore images. This is perception by others. In the mean time it may make a difference. But that is not for me to say.
Thanks,
GerardM
PNG is suitable for some types of images such as maps. With photography TIFF format is preferable.
As far as I remember, the reason TIFF is not allowed is that TIFF is a container format which can contain a whole bunch of different things, including some things that might be problematic for security or stability reasons.
Some kind of TIFF validator would solve that problem, ensuring that uploaded TIFFs were good and contain just regular image-y stuff.
While TIFF is something of a standard it isn't a very good one. Main problem is that it is more of a collection of (mostly) closely related formats rather than a clear single one.
It's popularity amoung certian groups is probably due to legacy issues.
From mediawikis POV it would be a major security issue to implement.
Durova writes:
"PNG is suitable for some types of images such as maps. With photography TIFF format is preferable."
I'm curious as to specifically why that is. What's different between maps and photographs as far as these two formats go? For that matter, what's different between the two formats? They're both lossless so they should both produce the same pixels in the end.
The only drawback to PNG for photos that I know of is that its file size may be larger. Its compression is lossless, but more optimized for diagram-like than photo-like images. TIFF is actually often much worse because no compression may be used. PNG is a well-defined standard, but TIFF has so many variants that it is almost never completely supported. One other thing TIFF has but PNG doesn't is support for multiple images inside a single file.
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