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Ask Slashdot: How To Determine If a Video Has Been Faked?
BStorm writes "The Toronto Mayor Rob Ford has been making headlines around the world, for allegedly smoking crack. This story was first broken by gawker.com, which is now crowd-funding $200,000 to buy the video in question. What do you look for to determine if a video has been faked? Of course I am only interested in the technical details and not the tawdry details related to this case ;) I live in Toronto, so the video still frame posted on Gawker certainly does look like Rob Ford."
If you want to edit or create videos, there's no better software than Windows Movie Maker. Create real or faked videos - it's all possible.
I usually look at the pixels. I've seen a lot of them in my time, so I can usually tell when they're fake.
http://www.geek.com/news/why-it-was-impossible-to-fake-the-1969-moon-landing-1537386/
It's fairly similar reasons why the Ford Video is real, and explains why His Immensity hasn't had anything to say since the story broke.
Shoes for Industry. Shoes for the Dead.
Most of the time when a picture or video has been faked or photoshopped, you can probably tell if you look at it carefully. Their usually isn't something quite right, about it, that most people will miss.
For example odd lighting. If you superimpose an image chances are you do not have the lighting just right.
Picture Fragments. Sometimes if you look at photoshopped pics (Even professional ones) you might find extra or removed limbs or fingers. Or some impossible feat of a part of the body that somehow is in front of something that couldn't possible be.
Extra Sharp or Blurry: Sometimes thing of interest that is added in later is taken with better skills than the background so you will see a blurry picture with a sharp object. Or they will cover up the whole picture by making everything blurry. If the image seems like it was taken from an iPhone but it was super blurry more than what the device does you can probably expect it has been altered somehow.
Dithering/Anti-Alias methods: Most digital cameras on full resolution tend to have some dithering to the colors (Those sparkly bits that don't seem to exist in real life) Then some equipment scales it down a bit and adds some Anti-Aliasing to make the colors more smooth and natural looking. If you add a fake element chances are those methods will be different. Say a smooth well anti-aliased pipe, with a dithered person.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
With jpeg(and I think at least some of the mpeg flavors), quantization matrices can be your friend.
Different hardware and software uses different matrices. This isn't a slam-dunk(if somebody just lightened the image a bit to bring out the detail, the quantization matrix would scream "Photoshop!", despite that being pretty innocuous); but it makes it rather harder for a clueless faker to simulate a 'right off the camcorder' "authentic" video if the last compression was almost certainly performed with editing software.
Depending on the details of the format, there are likely to be a variety of other things that are optional or implementation-specific(at least within certain ranges) that can be examined to try to source a given file. If implementation(or quality level/encode settings)-specific details vary between sections of the video, or between parts of individual frames, that's probably a bad sign.
If you have enough footage, and ideally access to the alleged source hardware, you can also attempt to characterize physical defects in the sensor. All digital image sensors, to one degree or another, exhibit imperfect linearity. Some pixels are 'hot', some are abnormally insensitive, this is especially visible on long exposures, or in very dark scenes, where the hot pixels tend to stand out. Onboard image processors have gotten increasingly good at squelching minor sensor noise, so this isn't easy; but a given CCD or CMOS sensor will have a noise pattern that is extremely difficult to replicate. It's just an open question whether you'll actually be able to see enough noise to identify it.
Q: Has the person appearing on it sued the pants off the holders?
Yes: Probably fake
No: Most likely genuine
What Mayor Ford doesn't want to admit is that the video is real, but it was taken while he was in the middle of secret negotiations with rival Toronto and Scarborough gangs. Ford was trying to broker a peace treaty and also recruit the gang members to work as the city's new sanitation engineering team, allowing him to cut the fat at city hall and pass on the savings to the taxpayers he respects.
Due to the tense nature of the meetings and the highly strung personalities present, Ford was loathe to bring something so provocative and weapon-shaped as his asthma inhaler, so he had no choice but to settle for a large glass pipe filled with prescription corticosteroids.
To minimize the possibility of rival gangs finding out about the meetings, all discussions were conducted in code. When he said "Justin Trudeau’s a fag", what he really meant was "I agree with your interpretation of paragraph seventeen, but I still feel that it contradicts the spirit of section seven which is also laid out in the preamble" and "those kids are just effing minorities" was a code phrase for "We cannot compromise on the issue of banked sick days, and have you ever been to the Russian Tearoom on Adelaide? Their curried chicken salad is to die for."
It's all quite obvious when you look at it. It's just the vast left wing media conspiracy that is trying to blow it out of proportion and make it look like something inappropriate.
Gawker is spending $200,000 to get a rise out of embarrassing a politician. It would be far to use it for something such as donating to the EFF, fighting the next SOPA or some other similar cause. Donating personal money for this cause is something only a tool would do.
You submit it to Mythbusters.
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Does the video include footage of a female having an orgasm?