This document discusses capabilities and limitations of AI in detecting video manipulations such as deepfakes. It describes how AI can help identify manipulated videos through techniques like reverse video search, near duplicate detection, and video forensics. While AI shows promise in combating disinformation, current methods still have limitations and complete automation remains a challenge. A portfolio of tools is needed since no single technique can fully solve the problem.

1. Video & AI: capabilities and limitations of AI
in detecting video manipulations
Athens, Nov. 2019
Research Director, CERTH-ITI
Dr. Vasileios Mezaris

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• Deep fakes are new…
• …but fakes are not a new phenomenon!
AI as facilitator of disinformation
Haiti earthquake video hoax (Jan. 2010): Video from a previous
earthquake in California published by major media, slightly modified
(cropped) and re-circulated in social media as a Haiti video; picked-
up and aired by mainstream media for hours
Presidential fake picture (Jan. 2013): Video frame of a surgery
operation in Mexico in 2008, was sold to and was mistakenly
published by a top newspaper, supposedly depicting the
Venezuelan president Hugo Chavez under surgery in a Cuban
hospital.
https://www.youtube.com/watch?v=JbzVhzNaTdI

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• What makes deep fakes different?…
• Easier to create high-quality(?) fakes -> more people can do it
• Easier to create multiple fakes -> more media items can be created in
support of a disinformation campaign; can give rise to Distributed Denial of
Truth (DDoT) attacks
• …and what remains the same?
• A deep fake is usually an altered version of an original video; only the
means of introducing the alteration differs
• The techniques typically applied for detecting video-borne disinformation
are still useful (but there is also room for developing techniques specifically
tailored to detecting deep fakes)
AI as facilitator of disinformation
www.invid-project.eu

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• How can AI help?
• Understand the structure of the video; select characteristic frames for
visual inspection or reverse search on the web
• Find near-duplicate videos, or semantically-related videos (of the same or
similar incidents)
• Video forensics
AI for combating disinformation

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• Tool for verification of selected newsworthy videos
InVID Verification Plugin
• Free! Get it from: https://www.invid-project.eu/verify
Continues to be developed; now with new look in v0.71 (released June 7, 2019)
•
• Check prior video
use: reverse video
search on the Web
• Check contextual
information: Social-
media-based
contextual analysis
• View location, time
and other video
metadata
A browser plugin to debunk fake news
and to verify videos and images
>15.000
users
• Keyframe/image inspection by magnifying glass
• Check image (keyframe) forensics

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• Tool for advanced video verification
• Check prior video use at the video-segment level:
InVID Verification Application
•
•
• Reverse video search also in the InVID repository; inspection by parallel playback
of query and duplicate video
• Check video origin and rights:
• Video logo detection
• Video rights management
• Check video forensics:
• Video forensic filters
• Frame-level video inspection
• Check additional contextual
information
• Store the automatic analysis results and manually add evaluation
comments and notes
• Free demo version accessible at: http://invid.condat.de

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InVID Verification Plugin – Reverse search
https://www.youtube.com/watch?v=OVAxQA3gMEo
“Video, the crowd in panic flees
from Notre Dame in Paris after
the attack of an armed man”

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InVID Verification Plugin – Reverse search
https://www.youtube.com/watch?v=OVAxQA3gMEo
“Video, the crowd in panic flees
from Notre Dame in Paris after
the attack of an armed man”

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InVID Verification Plugin – Reverse search
https://www.youtube.com/watch?v=OVAxQA3gMEo
“Video, the crowd in panic flees
from Notre Dame in Paris after
the attack of an armed man”

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InVID Verification Plugin – Reverse search
https://www.youtube.com/watch?v=OVAxQA3gMEo
“Video, the crowd in panic flees
from Notre Dame in Paris after
the attack of an armed man”

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InVID Verification Plugin – Reverse search
https://www.youtube.com/watch?v=OVAxQA3gMEo
“Video, the crowd in panic flees
from Notre Dame in Paris after
the attack of an armed man”

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• Video forensics – a quick AI-based approach
• Filters generating heat maps (e.g. Cobalt: compares the original video with
a modified version of it, re-quantized using MPEG-4 at a different quality
level, and generates the error video)
• Use deep learning architectures (e.g. GoogLeNet, ResNet) to learn from
both the video itself, and the outputs of these filters
• No knowledge of the generator’s characteristics is assumed
• Results are promising, but not a complete, deployable solution yet [1][2]
AI-based video forensics
[1] M. Zampoglou, F. Markatopoulou, G. Mercier, D. Touska, E. Apostolidis, S. Papadopoulos, R. Cozien,
I. Patras, V. Mezaris, I. Kompatsiaris, "Detecting tampered videos with multimedia forensics and deep
learning", Proc. 25th Int. Conf. on Multimedia Modeling (MMM2019), Thessaloniki, Greece, Springer
LNCS vol. 11295, pp. 374-386, Jan. 2019.
[2] "Video verification in the fake news era", V. Mezaris, L. Nixon, S. Papadopoulos, D. Teyssou (Editors),
Springer, 2019.

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AI-based video forensics
Detected
Fakes
Fakes not
detected
(lower
resolution)
Videos from the InVID Fake Video Corpus
1280x720p480x360p
320x240p 320x240p

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• Video forensics – a steganalysis- & AI-based approach
• Steganalysis features are extracted from each frame [3]
• Sliding windows of 128x128 pixels are considered
• High pass filtering of pixel values, then calculate and quantize residuals; co-
occurrence matrices are calculated
• A recurrent autoencoder is trained on pristine frames of the video
• The trained autoencoder assesses the remaining frames of the video
• Forged spatial regions in manipulated frames are singled out as anomalous
• Good results plus localization of the forgery; but sensitive to encoding
AI-based video forensics
[3] D. D’Avino, D. Cozzolino, G. Poggi, L. Verdoliva, “Autoencoder with recurrent neural networks for
video forgery detection”. In: Electronic Imaging 2017.7 (2017), pp. 92–99.

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• Video forensics – a steganalysis- & AI-based approach
AI-based video forensics
Video from the UNINA dataset
http://www.grip.unina.it/

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• Looking at the greater picture – directions & thoughts on deep
fakes and AI-based video forensics
• Manipulated videos and deep fakes still usually come from an original: if
you find the original out there, you have documented the faking
• Reverse video search is still a powerful tool
• AI has great potential; is already used in different techniques for
combatting disinformation, and will be used even more for video forensics
and detecting deep fakes
• But, no single tech seems to be the solution; we need a portfolio of tools [4]
• Complete automation is a challenge!
AI-based video forensics
[4] "Video verification in the fake news era", V. Mezaris, L. Nixon,
S. Papadopoulos, D. Teyssou (Editors), Springer, 2019.

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Dr. Vasileios Mezaris
Information Technologies Institute
Centre for Research and Technology Hellas
Thermi-Thessaloniki, Greece
Tel: +30 2311 257770
Email: bmezaris@iti.gr, web: http://www.iti.gr/~bmezaris/
For more information on the InVID project, visit www.invid-project.eu
Follow InVID on Twitter @InVID_EU
Contact

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This work was supported in part by the EU’s Horizon 2020
research and innovation programme under grant agreement
H2020-687786 InVID.
Acknowledgement