Stopping people from uploading pornographic images

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mattcooper
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Stopping people from uploading pornographic images

Post by mattcooper »

Hello everyone! I'm currently developing a software package in php, part of which allows people to upload images to a database. I am concerned that some users may abuse this by uploading pornography, which would be publicly viewable.

Having hunted high and low for ways of detecting whether an image is pornographic (based on flesh tones, I would have thought), I am now stumped, as can't find one!

Can anybody help?
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Chris Corbyn
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Post by Chris Corbyn »

I think you just need to moderate it....

It'd be nigh on impossible to detect pornography - I could just upload in black & white anyway if you're working on flesh tones. Besdies with such a variation in skin tones across the globe it's off to a bad start :idea:
Last edited by Chris Corbyn on Thu Mar 17, 2005 6:20 am, edited 1 time in total.
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onion2k
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Post by onion2k »

I would imagine its not possible. Firstly because you can have images that are mostly flesh tones that aren't porn (eg, a portrait), and secondly because some porn have people wearing clothes.

If you're that worried about it, build it so that all images uploaded have to be checked by a moderator before they're available on the site. Or, alternatively, have a system so that people can click a 'complain about this image' button that takes it off the site until its been checked by a moderator.

Whatever happens you're going to need a human checking things.
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mattcooper
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All very good points..

Post by mattcooper »

I kind of knew that this would be a tough one! Will go with the "complain about this image" option, which I think is the best compromise.

Unless anyone else has a pearl of wisdom!!!

Keep 'em coming!

Thank you for replies so far.
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JayBird
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Post by JayBird »

...or you cold use some kind of approval system.

All images are queued for approval before they appear in the gallery. Then you can view the queue, and choose to either allow or disallow each of the images
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feyd
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Post by feyd »

moderated system, and a "notify moderator" link/thing are both good ideas to use.
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mattcooper
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OK, but...

Post by mattcooper »

Thank you for all suggestions so far..!

The software allows the user viewing a demo site to upload images to a database, then select an image for inclusion in a demo page. The images would remain in the database for a finite length of time, then be deleted. However, if before the delete happens a new user visits the demo site and there is a pornographic image in the database, they will be able to view it and our site will lose credibility. Unfortunately we don't have the time to moderate the images!

Are there no image filters in existence that I can use?? something that could flag suspect images as potential porn?

Keep thinking! :D
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Ambush Commander
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Post by Ambush Commander »

Nope. That's why google image searches (relies on text, so picture can be totally irrelevant) are so bad and captchas are so effective (heck, everyone uses them). A swift, no-nonsense, instant ban policy will help though.
Roja
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Re: OK, but...

Post by Roja »

mattcooper wrote:Unfortunately we don't have the time to moderate the images!
You have three choices, no more, no less:

1. Spend the time to moderate the images. This is your investment to acheive/maintain the "credibility" of your site (as you put it).

2. Let users moderate the images. This allows you to build a web of trust with key users, has them invest themselves in the site, and builds the credibility by consensus - not by force and automation.

3. Do nothing regarding moderation, and simply ban people who break the rules when you find them.

In any case, if you choose to do moderation, having only moderated images displayed will help remove the potential for loss of credibility.. if it means a 24 hour turnaround time before the images are available, so be it.

In either case, you can't automate away the need for humans. :)
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feyd
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Post by feyd »

it would require an extremely powerful analyzer.. and even then, it may have false positives and remove things like artwork, which are perfectly legal. The filter required would take probably a supercomputer level machine to process in near realtime.

You could make the images only available to their session, (excluding the "defaults" that already exist in the database) on the demo..
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