Welcome to the Jungle

Understanding video standards is fundamental to aspect ratio correction. Back in the predominantly analog days we had three main standards referenced or used for most video recordings; NTSC, PAL, and SECAM. Then in the early ‘90’s came the first digital multimedia frameworks to reach the average consumer; QuickTime and, shortly thereafter, Video for Windows (VfW).

Today we have dozens of multimedia frameworks, digital video and digital display standards, all of which lead to a great deal of confusion regarding the plethora of acronyms and what they truly mean. AVC or H.264? HEVC or H.265? CIF or SIF? Don’t even get me started on the profiles and parameters available for each standard, as the combinations are truly mindboggling. When it comes to proper Display Aspect Ratio (DAR) though, it really boils down to “Are the originally recorded pixels square or non-square?”

I was out in Indianapolis last week to assist with the LEVA Level 1 training course. Another great week of forensic video and DME training provided by LEVA, and hosted by the University of Indianapolis.

It was an action packed week both in the classroom and out with students learning and practicing DME fundamentals, and the City bustling with NBA playoff and Indy 500 activities. Thank you to LEVA, their staff, my employer Ocean Systems, and the students for such an incredible opportunity.

Safe travels home everyone and have a great holiday weekend!

The multimedia evidence community has been really buzzing the last couple of years in regards to how useful FFmpeg and Libav can be for dealing with proprietary video formats. Both tools are extremely useful in several aspects of a forensic DME workflow. With that said, however, whether it’s FFmpeg, Libav or another 3rd party tool, there are limitations and causes for concern when using them to process proprietary video file formats.

Although disc-based storage is not as widely used as it once was for digital evidence archiving, it remains a viable solution when properly implemented and managed. In fact, many of the world’s largest technology companies are using and/or exploring disc-based storage systems for long-term offline storage of petabytes of customer data (e.g. Facebook uses 10,000 Blu-ray discs to store 'cold' data). They do so, however, in a managed environment with a thorough understanding of the medium’s strengths and limitations.

Many in law enforcement use write-once disc-based media for MASTER evidence storage, as it continues to be recommended via various industry best practice documents. Unfortunately, not everyone involved in the evidence chain understands the limitations and best practices as they relate to the care and handling of disc-based media. Adhesive labels, permanent markers, and ballpoint pens have destroyed more evidence than I care to even think about.