Forensic Video Analysis : Real Videos vs Fake Videos - Video Forensics

Forensic Video Analysis
Forensic Video Analysis
Forensic Video Analysis: Video Forensics

Now in December 2018, almost every person has a camera and mobile so everyone can create videos, make images. We in our daily life make a lot of images and videos and this is the reason that now in many court cases videos are given as an evidence in court. If a Case running in court and videos are given as a evidence then these videos will get tested in a lab that they are original or fake then the lab gives the results about videos and case will move forward on the base of lab decision.

Do you ever think that in Lab what process was done through which they check that the video presented is fake or original?
If we talk about video editing in past, where editing is very difficult, when for editing a little part of the video many hours used and video editing word is connected to Hollywood movies but if we talk about video editing in today than we see then today video editing is easy, many free and easily downloadable algorithms are available that can run on a normal computer, that algorithms get face details and swap faces. 

I am talking about Deep Fakes which was recently very popular and if you can give this algorithm two videos with two different faces than this algorithm automatically change faces of both persons. That seems like a weird thing when we think about it, because in past, it was not normally available as it is now, this is the reason today video forensics get very important, because many face swap type algorithms are available in the market so there are many chances that the presented video is also fake, So how they check that the video is real or fake.

The first and most useable technique is seeing, First of all they see the video clearly, watch every area and every part of video to see that is there something looking weird, or some different because when someone doing normal video editing the area which is edited, pixels are not exactly matching  and if some new video editor do video editing then we also see difference in edges, so they get to know that this video was fake and was original. Humans eyes are working in a limit at that condition but If a good level video editor do editing then its difficult for the human eye to see the edited area. In that conditions, computers were used, basically, in computers, there are algorithms that see every pixel of the image and if on some point they see the difference they understand that this image is edited. If you talk about the camera than two adjacent pixels are not too different and when this is implemented on videos than frames from videos were check that the video is original or fake.

The second technique is a very interesting technique because In this technique compares algorithms were used. When someone used video or audio editing software then after editing when software saves the image then that image was saved in a specific format and normally left his footprint with the image. If someone edits a photo in adobe photoshop then there are many chances that in the code of photo somewhere fingerprints of adobe photoshop is present. When a normal eye sees that image, then the images look real not edited but when you see about compereshan elements of the image you know that through which software this photo was edited. It's easy to find that image is edited when someone edits them with a popular software or algorithm but when a low known software or custom algorithm was used then this technique is not fully worked because its very difficult to know about every software, normally only popular software are tested.

When they can't know that in which software image is edited, they ask a question that this video is edited or raw, they asked this because in courts normally evidences videos come directly from CCTV cameras or mobile phones, so when they see in the coding of video then they clearly know that the video is edited from which device because every image sensor when record a video or image, record it in a specific way and almost all camera's normally used in market, footprints are different. When they know that the image or video is created from which device than they get assured that the image or video is edited or not because when someone edits an image or video its footprint from the device from which it was created were not remain.

When this technique gets failed they take help from physics and science and using them they see the direction of lights in image or video, If on somewhere light direction is different from other points then they get know that on that point image was edited.
These are the techniques that are used to check about videos that they are real or fake and the first technique (seeing) is the commonly used technique to check videos, they are real or fake. Hope you learn something new, If you like this then leave a beautiful comment, Subscribe us by email and don't forget to share because sharing is caring. Thanks
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