The spectrogram capabilities of my DAW are very limited so I looked around for a free utility and, not finding anything suitable, decided to build my own utility for creating a spectrogram.
Here's what I'm seeing in the relevant section of audio referenced in the "Video [that] claims shooter dressed as police".
* This audio was filtered to remove as much of the crowd noise as possible. * Lower frequency sounds (the muzzle reports) are graphed at the top - higher energy sounds towards at the bottom. * More work to be done adding time and frequency indexes, zooming, anotating etc but it looks promising.
This is just a progress report. I will document the complete methodology as time allows.