DIGITAL FORENSIC RESEARCH CONFERENCE

MP4 Video Authentication Using File

Structure and Metadata

By

Jake Hall

Presented At

The Digital Forensic Research Conference

DFRWS 2015 USA Philadelphia, PA (Aug 9th - 13th)

DFRWS is dedicated to the sharing of knowledge and ideas about digital forensics research. Ever since it organized

the first open workshop devoted to digital forensics in 2001, DFRWS continues to bring academics and practitioners

together in an informal environment. As a non-profit, volunteer organization, DFRWS sponsors technical working

groups, annual conferences and challenges to help drive the direction of research and development.

http:/dfrws.org

MP4$Video$Authen/ca/on$Using$File$Structure$and$Metadata$ $$

Jake$Hall$

MP4/3GP$Video$

•  Video$Coding$Formats$– H.264$– MPEGE4$Part$10$

– Advanced$Video$Coding$(AVC)$•  File$Container$Format$– MP4$– 3GP,$3G2$

Movie$Atoms$

•  QuickTime$File$Format$Specifica/on$•  Allow$the$media$and$the$descrip/on$to$be$stored$separately$$

•  Size$>$Type$>$Data$•  Parent$/$Child$Nes/ng$Conven/on$

Original$Go$Pro$Hero$3+$Black$

Parsing$$

•  4$bytes$@$0x00$–$size$of$atom$–$32$bytes$•  4$bytes$@$0x04$–$type$of$atom$–$^yp$

•  File$Type$Compa/bility$

Parsing$

•  4$bytes$@$0x20$–$size$of$atom$–$22742$bytes$•  4$bytes$@$0x24$–$type$of$atom$–$moov$•  4$bytes$@$0x28$–$size$of$atom$–$108$bytes$•  4$bytes$@$0x2C$–$type$of$atom$–$mvhd$–$Movie$Header$Atom$

$$^yp$@$0x00$moov$@$0x20$•  mvhd$@$0x28$•  udta$@$0x94$

•  FIRM$@$0x9C$•  LENS$@$0xB0$•  CAME$@$0xE8$•  SETT$@$0x100$•  AMBA$@$0x110$•  free$@$0x190$

•  trak$@$0x214$•  tkhd$@$0x21C$•  tref$@$0x278$

•  tmcd$@$0x280$•  edts$@$0x28C$

•  elst$@$0x294$•  mdia$@$0x2B0$

•  mdhd$@$0x2B8$•  …$

71$atoms$in$total$

Using$Atomic$Parsley$to$Render$Original$Go$Pro$

Examples$of$Unique$Atom$Data$

Adobe$Premiere$Structure$Change$

Original$vs.$Premiere$

ffmpeg$Structure$Change$

Original$vs.$ffmpeg$

Comparison$With$Other$Devices$Panasonic$Lumix$$$$$$$$DMC$TSE5$ LG$G3$

Samsung$$Galaxy$S5$

Samsung$$Galaxy$S4$

Samsung$$Galaxy$S3$

Notes$

•  Forensic$Analysis$of$Video$File$Formats$by$Gloe,$Fischer,$Kirchner$– hkp://dx.doi.org/10.1016/j.diin.2014.03.009$

•  QuickTime$File$Format$Specifica/on$– hkp://developer.apple.com/library/mac/documenta/on/QuickTime/QTFF/qnf.pdf$

•  Atomic$Parsley$– hkp://github.com/wez/atomicparsley$