Video Analysis Tool Box for Digital Video Forensics By Susinda
Perera Department of Computer Science and Engineering, University
of Moratuwa, Supervised by Dr. Chathura De Silva PhD
(NUS-Singapore), MEng (NTU-Singapore), BSc Eng.(Hons) (Moratuwa)
Senior Lecturer Department of Computer Science and Engineering,
University of Moratuwa, 02-02-2014 Slide 2 Agenda Project Intro
Implementation Video Stream Analyzer Video Stabilizer Compressed
domain video analysis Demo Video Stream Analyzer Video Stabilizer
Slide 3 Problem Statement Can we trust digital videos? Are they
real, computer generated or tampered Extract some wanted
Information from video Difficult due to unclearness of video Slide
4 Can we trust digital videos? Figure 1 1 : A still from
controversial video aired on Channel 4 Source YouTube
http://www.youtube.com/watch?v=rjVxyG_7mTkhttp://www.youtube.com/watch?v=rjVxyG_7mTk
Slide 5 Can we trust digital videos? Figure 1 2 : A still from
eagle catching kid Source
http://www.cbc.ca/news/canada/montreal/child-snatching-eagle-video-created-as-student-project-1.1268125
Slide 6 Unclear Videos Slide 7 Solution Video Stream analysis tool
To ensure the authenticity and integrity Video Enhancement tool To
improve the visual quality Slide 8 Market Analysis Video Stream
Analyzing Tools Elecard StreamEye Elecard StreamEye Tektronix MPEG
Software Tools Tektronix MPEG Software Tools MPEG-2 Transport
Stream packet analyser MPEG-2 Transport Stream packet analyser
TSReader TSReader MTS4EA Elementary Stream Analyzer MTS4EA
Elementary Stream Analyzer Slide 9 Screenshots from Elecard
StreamEye Slide 10 Some Features Of Video Stream Analyzing Tools
Navigation and display of media stream picture-by-picture (I, P,
B). Display of the current frame. Display of the time, type, size
and number of a current frame in a stream, decoding order and
offset from the file beginning. Display of the bit rate (declared
in the sequence header) and a calculated bit rate. Display of
detailed information about macroblocks in MPEG-1 (ISO/IEC 11172-2),
MPEG 2 (ISO/IEC 13818-2), MPEG-4 (ISO/IEC 14496-2) and AVC/H.264
(ISO/IEC 14496-10) video streams. Information about motion vectors
Frame-accurate positioning. Display of the stream and gathering of
statistics relating to the entire file. Slide 11 What is missing in
existing tools All high end tools are commercial ones, Expensive
Almost all tools are designed for DVB purposes Lack of detailed
analyzing features for video forensic Lack of textual
representation Slide 12 Video Forecsic /Enhancement Software
Cognitech Ocean Systems dTective Salient Stills VideoFOCUS
StarWitness Avid Technology, Inc. Intergraph Video Analyst TREC,
Inc. Forevid MotionDSP Ikena Amped FIVE Kinesense Slide 13 Slide 14
Features Of Video Enhancement Tools Video Stabilization Denoising
Deblur Filters Detection Filters Enhancement Histogram Editor
Segmentation Tracking Transform Zoom Velocity Reconstruction Slide
15 Implementation of Video Stream Analyzer Slide 16 Literature
Review Market Analysis Most of tools are for DVB, not for forensic
purposes Lack of textual output Possible resources [31- 35] Video
Player libraries / source codes Decoder Libraries/Source Codes
MPEG2Event[33]is a possible candidate Slide 17 Video Stream
Analyzer Implementation Based on MPEG2Event[33] library Mpeg
demuxer ffmpeg for stream information A simple thread sync model to
get motion vectors Quartztype library for video player
implementation C# inbuilt xml libraries for xml manipulation Slide
18 What is MPEG stream MPEG Bit-Stream Structure (Source [1] )
Slide 19 GOP Structure and Display order GOP Structure and
Transmission Order. (Source: [2]) Slide 20 Video Stream Analyzer
https://code.google.com/p/mymscproject/source/browse/tr
unk/Experiments/Mpeg2Event/Downloads/VideoAnalyzerSe tup.msi?r=174
Slide 21 Video Stream Analyzer Features Free and open source
Textual output (xml) of analysis reports For further analysis All
most all the features in slide 10 Motion vector display Frame
navigation Bit stream index/ Display index view User data display
Motion vector summary xml output Full video summary xml output
Slide 22 Video Stream Analyzer -outputs Slide 23 Motion Vectors
Summary I 0 false true I 0 1 0 false true I 0 2 0 false true I
Slide 24 MacroBlocks Summary Slide 25 Implementation of Video
Enhancement tool Slide 26 Video Enhancement Tool Objective Enhance
the visual quality Video Stabilization Noise removal Color
Correction Slide 27 Video Stabilization Removing annoying shaky
motion from videos helpful in identifying people, number plates,
etc. from low-quality video cameras Three aspects Inter frame
motion estimation Motion smoothing and compensation Filling up the
missing image areas. Main references [3], [4], [5] Slide 28 Video
Stabilization Inter Frame Motion Estimation Result of video
stabilization. Top row: Original input sequence, middle row:
stabilized sequence which still has missing image areas, and bottom
row: stabilized and completed sequence. The grid is overlaid for
better visualization. (Source [3]) Slide 29 a) Natural scene, b)
when camera is moved, c) when image is shifted to compensate the
motion. Handling camera motion Slide 30 Motion Model Slide 31
Motion Estimation Slide 32 Stabilization Slide 33 Motion Smoothing
A stabilized motion path is obtained by removing undesired motion
fluctuation. Assumed that the intentional motion in the video is
usually slow and smooth Uses Gaussian kernel in most literatures
Applies Gaussian kernel to neighboring N frames Gaussian kernel +
curve fitting methods Slide 34 Motion Smoothing Let N t =
{j|t-k
