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Things I Learned: Cropping QSL Videos Using ffmpeg

 I'm working on creating video clips of each QSO during a POTA/SOTA activation.

I was inspired by K4SWL's YouTube channel. Thomas records his entire activations without edits. For various reasons, my outings so far have required edits. I've been recording using my cell phone and a variety of things happen because of that. For example, I can't ignore incoming texts because I'm the 'guy in the chair' for three kids. I don't, however, need to publish those messages either, so for some clips, I need to crop the top of the phone screen away. That's where this ffmpeg post came in handy.

To clip off the notifications in the top of the screen, I used

ffmpeg -i serccrab.mp4 -ss 00:02:11 -t 00:01:14 -vf "crop=in_w:in_h*.80" -c:a copy ki6pxv_sh2.mp4

Where the extra argument 

-vf "crop=in_w:in_h*.80"

Clips off the top 20% of the screen. Here's the QSO. You'll hear the phone vibrate, but the message across the top of the screen isn't visible anymore. in_w and in_h stand for stand for the width and height of the video respectively in pixels.

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