REVerse engineering of audio-VIsual coNtent Data

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REVerse engineering of audio-VIsual coNtent Data
General Information
Features
FP7 FET EU-Project, 05/2011-04/2014, 1.6 Million €
Scientific impact: A total of 100 publications in international
journals and conferences
• Reconstruction of the process history of A/V content via signal
processing, machine learning and information theory under the
assumption that actions leave characteristic footprints
Final project rating: “excellent”
• IDMT contributions:
1.Analysis of process operators and chains:
Web: http://www.rewindproject.eu/
• Sampling plagiarism detection
Partner
Type
Country
• Inverse decoder (a) MP3, (b) AAC and (c) MP3PRO
Politecnico di Milano (Polimi) - Lead
Academic
Italy
Consorzio nazionale interuniversitario
per le telecomunicazioni (cnit)
Academic
Italy
• Audio tampering detection and authentication using
(a) ENF & stable tones, (b) microphone classification,
(c) inverse decoder, (d) Benford’s Law
Fraunhofer IDMT
Research Institute
Germany
Imperial College London
Academic
UK
Universidade de Vigo (Uvigo)
Research Institute
Spain
• Storage and retrieval of content and related XML annotations
Universidade Estadual de Campinas
(Unicamp)
Academic
Brasil
• Graph processing and search support for processing chains
2.Evaluation:
Analysis of process operators and chains
Plagiarism detection - example
• Evaluation of detectors
• Development of a service for automatic testing:
• Support for distributed, automatic testing of components
Audio tampering detection / authentication
• ENF & stable tones
Use Case: Audio editing – Sample plagiarism
• Phase analysis / discontinuity checking (extraction, phase estimation,
finding discontinuities, segmentation)
Detector Candidate: Audio – Sampling plagiarism detector
• ENF temporal pattern matching
Typical chain:
• Microphone classification / discrimination
Aquire & Code – Crop Sample & Process Mix – Code
• Inverse decoding: Frame offset detection
• Application of Benford‘s Law (e.g. MDCT coefficients)
• Synergetic combination of all aforementioned approaches
• Attacker aware approaches (ENF concealing, removal, substitution, …)
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Time [ sec ]
Inverse decoder
Automatic Testing Service
Detection of compression traces and parameters from previously
encoded (MP3/AAC/MP3PRO), now decoded audio material via
translation back to its bitstream representation
• Action-based annotation approach (actions and thus contentannotation pairs as nodes) using XSD; XSD for detector interfaces and
use case tests; mapping to annotations via XPATH
• Determine decoder framing grid (for MP3: MPQF + MDCT + Statistics)
and frame offsets
• Service for bulk upload & download, previewing, authorization,
search and visualization of processing chains
• Block type detection, and estimation of quantization information
from quantized spectral values  bitrate estimation, stereo coding
type detection and other parameters
• Client-Server setup for distributed, automatic evaluation: No
integration of detectors necessary
• Service could be extended to on-the-fly test content generation