Here is one study on the methodology for extracting the gunshot signal.
Identification of shockwave and muzzle blast in a gunshot signal using frequency analysis techniques | IEEE Conference Publication | IEEE Xplore
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thanks!
while reading this type of articles, one has to keep in mind that there are several possibilities:
- non-suppressed gun, supersonic ammunition, short barrel: muzzle flash is visible, explosion can be heard, bullet breaks through sound barrier
- same as 1, longer barrel: less/no muzzle flash
- non-suppressed gun, subsonic ammunition, short barrel: muzzle flash may be seen, explosion can be heard, bullet does not break through sound barrier
- same as 3, longer barrel: same, but muzzle flash is less likely
- suppressed gun, supersonic ammunition: muzzle flash is very unlikely, explosion is more a poof than a bang, bullet breaks through sound barrier
- suppressed gun, subsonic ammunition: muzzle flash is very unlikely, explosion is not heard, bullet does not break through sound barrier
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I am looking at the second toll building behind Crooks and wondering if the vents over there could be used to fire? Instead of laying on the hot roof?
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I will look into it and let you know
Yeah and she has been bugging me for a long time. Not hard to get a make on her if one knows how. I kept thinking why is she out there?? Thanks been looking for that picture.
the SWAT team had been activated on higher alert already 6-7 minutes before the first shots were fired…
given that they were standing next to the tents and did not want to draw too much attention to their presence to keep the general public under control, it would make sense that they sent out one of them to go have a look.
in the bodycam footage it is clear that immediately after the 1st shot he positioned himself, took aim by the 3rd shot and fired immediately after the burst of 5 went off, so his response time was about 4 seconds…
I think such a response time is fairly quick when starting from walking around to hitting the man on the roof and/or his rifle…
and then, about 7-9 seconds later he looks through his scope to assess the damage, and here, I think he shot the 10th round to finish the man off.
I do not think the 10th shot came from any of the barn snipers as the damage to the body would have been considerably worse if he had been hit with a sniper rifle round (typically a .300 winchester magnum), and they were using suppressed rifles, and that round would likely have been subsonic…
this may seem many assumptions in 1 sentence, but it is clear they had suppressors on their sniper rifles and I believe that snipers 1 and 2 (the ones that had their line of sight hindered by the tree) returned fire almost immediately after the first round came in
I must admit that the following picture is more crooksy than the last picture
I never noticed it before, but it is highly unlikely that the middle picture was shot on that roof as there is some grass to be seen near his neck…
so, about this middle picture, the question becomes: why did that man suffer this damage?
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It doesn’t look like there’s much on the south side of that building. There’s a good chance the electric lines would also be in the way. The rooftop would probably be the best option for that building. Here’s some of my drone footage.
I suspect it was taken after he was removed from the roof and being body bagged. Or, if they bagged him on the roof once they got him to the ground someone wanted pictures and they unzipped him for the photo shoot. It looks like someone’s holding his head up for the photo. No doubt in my mind, it’s the same guy from the roof (who I believe to be Crooks).
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There are no “input parameters” for the 220ms. It is a direct MEASUREMENT of reality. See my post:
Which contains the video and the exact timings etc.
I also showed this visually in my audio software in this post
No, it’s the trees in the background; the photo has simply been cropped and rotated 90 degrees.
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I don’t expect it to make much of a difference, but I would like to update my TDOA model to use more accurate elevation data for the recording sources and gunshot locations. Would someone here be able to provide lat/lon/altitude data for:
- “Ross!” recording (PP source # 5?)
- “He’s got a gun” along fence (PP source #2)
- Dayve Stewert (PP source #6)
- Police cruiser that pulled up to entrance of AGR 6
- Podium microphone
- shooter’s position on roof of AGR 6
- Alternate shooter position: AGR 6 wall vent
- Grass area between North bleacher and inner fence (shot 9)
- Hercules 1 position on top of South Barn
If you don’t have accurate lat/lon data, that’s fine, I’m mostly interested in the altitudes since I think I’ve already got accurate lat/lon in my model now.
Hi Tibbs,
You know, I have been looking for the original video from the owner, who I call the guy with the “red checkered shirt” see my post below. Does anybody know this guy or the guy with the big black hat? We absolutely need original videos taken by the people who were at the rally. All hands-on deck: Does anybody know red checkered shirt guy? We need his original video!!!
@cmartenson I just published the latest update to my TDOA analysis, and I think I’ve made a compelling technical argument for the precise location of all 10 shots. I’ve put a huge amount of effort and hours to get to this point, so I would really appreciate it if each of the participants in this forum topic would take the time to watch the video and provide feedback, if any.
And thank you @vt1 for providing the formula for calculating the crack-boom time difference. Once I implemented that in the model, everything fell into place.
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It isnt weird that swat is out there. And her. It is weird that she is out there.
Nobody else around and… there she is, looking at AGR. And she leaves with USSS.
Does your result also apply if shots 1 to 3 were fired with a different rifle and different ammunition?
I watch them, Greg, all of them. I greatly appreciate all the hard work you put into this, and especially for posting your videos. That sets you apart. This latest video is by far your best yet. Kudos!
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To test that theory, I would would need to modify the model as follows:
- Choose alternate location (such as wall_vent)
- Use podium mic crack-boom times to determine velocities for those first three shots as if they were fired from the alternate location
- Apply appropriate crack-boom corrections to the recorders. For example, if the shots came from the wall_vent, the crack-boom corrections would only be applied to TMX and DJstew since the police cruiser was behind the line of fire and would not hear the crack.
Ground truth would be roof shooter @ shot 4 (unless you don’t think that shots 4-8 came from there, which would add another layer of complexity to the situation).
I will make those changes and give it a try.