https://bugs.koha-community.org/bugzilla3/show_bug.cgi?id=38655
--- Comment #17 from David Cook <[email protected]> --- (In reply to Mark Hofstetter from comment #15) Thanks, Mark. I'll have to set aside some time to go through your comment in depth. (In reply to Ujwal from comment #16) > So a PDF doc will have to be spilt into images per page and stored in a IIIF > server ? PDF doc split into pages - yes. Stored in a IIIF server - probably/potentially. There are ways of avoiding a IIIF server if it adds too much complication, although that adds complications of its own ;). > Yes I think a poor mans DRM would be OK .... If the images cannot be > downloaded that would be great. The library we are talking about is > basically a charity and the annual membership fee is USD 10 per year. From a technical standpoint, it is very difficult if not impossible to prevent images from being downloaded, because the image needs to be rendered on the user's screen. Once it's been rendered on the screen, it's possible for it to be captured in some way by that user. However, what we can do is add layers of security on top to make it more difficult to download those images. The same concept is used in all forms of security. For example, you put a lock on door handle to your house to prevent someone from just opening the door and walking in. But a determined thief will just break the lock or break a window and enter. So then maybe you add bars to the window and get a deadbolt for the door which is not so easy to break. That prevents that determined thief, but an even more determined thief will break a hole in the wall and enter that way. Ultimately, it's about measuring risk and implementing proportionate counter-measures. In this case, I think you have 3 key elements. First, only allowing authenticated users to view the ebook content (although you/we should keep in mind self-registrations and whether they should be able to view). Second, splitting the PDF into images, so that you're not transmitting the entire ebook to the user's computer at once. Third, using a web viewer like the IIIF Universal Viewer, typically prevents people from right clicking to save the full sized image (it's always possible to add some additional UI-based security on top of the viewer as well). Even if someone did a screenshot for the page, they'd have to manually do it for every page to try to reconstruct the entire ebook. While it is possible, it is not very likely. (There are also methods for automating it, but that would require a determined and experienced person looking to abuse the system and steal the ebooks.) -- You are receiving this mail because: You are watching all bug changes. _______________________________________________ Koha-bugs mailing list [email protected] https://lists.koha-community.org/cgi-bin/mailman/listinfo/koha-bugs website : http://www.koha-community.org/ git : http://git.koha-community.org/ bugs : http://bugs.koha-community.org/
