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Things I Learned: ffmpeg Video clips; Also KR4I QSO from US-0757

This is the POTA activation that just keeps giving.

Going through all the recordings of the blustery day POTA from US-0757, I wanted to make a few shorter clips. Consequently, I dusted off my nascent ffmpeg skills. One of the tings I had to find was how to make a video clip. Here's the command I'm using to divide my larger recordings into smaller ones:

fmpeg -i us_0757_waves.mp4 -ss 00:00:00 -t 00:00:48 -c:v copy -c:a copy sm0gjn.mp4

The -i argument is the input recording. -ss denotes where in the recording in hh:mm:ss format I want the clip to start and the -t argument indicates in hh:mm:ss format how long I want the clip to last. The -c arguents are telling ffmpeg to copy both video (:v) and audio (:a). The copy argument says to copy these thingis for the duration of the clip into the file name copying the 'copy' argument, (cm0gjn), in this case.

The clip procesing takes about two seconds, and for me anway, is so much faster than using any GUI video editing program I've found. 

I might take this and start to set up an automated clip per QSO. Let's try a few here. The following table shows all the QSOs with their UTC time for the activation

QSO Log

Callsignrx RSTtx RSTTime (GMT)Frequency
sm0gjn3393392024/11/18 15:49:0014057.4
na7jd4495992024/11/18 15:53:0014057.4
n1xk3395192024/11/18 15:55:0014057.4
ve7osh3392292024/11/18 16:01:0014057.4
kf0ge5594492024/11/18 16:03:0014057.4
k9osc4495392024/11/18 16:05:0014057.4
kk7nnc5795392024/11/18 16:15:0014057.4
n6dxn5595592024/11/18 16:03:0014057.4
kr4i4494892024/11/18 16:30:0014057.4
ve6lk5595392024/11/18 16:32:0014057.4
n0aie5895492024/11/18 16:42:0014057.4
kn7d5795592024/11/18 16:43:0014057.4

I already posted the QSO for SM0GJN, so let's try a different one. How about Kr4i? That was at UTC 16:30. Let's see how long this takes. It's 14:26 PST right now. At 14:30, I've made the clip and I'm uploading. At 14:34, I've filled in the YouTube forms and published the clip. Adding it below now.



And that's that. At 14:37 I'm done copying the short to this post.

What you're hearing in the video:

I got the idea for recording POTA activations from K4SWL. I haven't quite perfected my method yet, but I'm getting better at it. Here's what I'm doing. I'm dialing my phone into the Utah SDR, then turning on the screen recorder to record the screen as well as any media audio output, (the Utah SDR), and the phone's microphone. I listen to TouCans' audio output via a pair of Bose Bluetooth noise canceling headphones. the signal audio you'll here is from Utah. The waves crashing were under me in San Francisco.



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