Monthly Archives: October 2014

Measuring and graphing I-frame gaps in videos

I’ve been mired in IPTV related work for a while now, popping my head up occasionally to grab a breath and take a look at some other neglected things in my day-to-day job. It isn’t long before I’m back into it though, and all the time I’m picking up more knowledge about the world of TV.

One thing that was brought to me recently was some failures related to a network PVR system having trouble ingesting encrypted video content. According to the support team for the software, I-frames in the content were too far apart to ingest properly. The person working on the issue at our company was interested in seeing just how far apart they were, so I set to creating a little script to do just that.

It turned out to be relatively simple using ffprobe, which is part of the ffmpeg suite. Using that data, it’s then possible to plot the I-frame gaps with gnuplot.

iframe-distance-plot

I-Frame gaps

Continue reading