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Wednesday, May 29, 2013

Playing well with others

Here's an interesting scenario that I came across today.

One of the leading manufacturers of body worn audio/video recorders for law enforcement outputs AVI files from it's software using an MJPEG codec. Their proprietary video's frame rate varies - so the frame rate in the resulting file tends to vary too.

In general, our edit bay technology was designed for the broadcast industry (Avid, Adobe, Sony, etc). They don't like variable frame rate media. Thus, dropping these videos on a timeline, making corrections and other edits, then outputting to some MPEG file for inclusion in a detective's PowerPoint becomes problematic. Frame counts don't match. Frames get dropped/added according to the output codec. Ghosting can happen.

A discussion ensued. Edits were being done to the AVI transcoded copy that was being used for demonstrative purposes. The original files were unchanged and remain in their proprietary format - available for the court if necessary. So ... the question - does it make a difference if the frame counts don't quite match (demonstratives vs. originals) as long as the essential details of the case are preserved?

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