To edit 4K video with OpenShot smoothly without crash and choppy, you can follow this video to compress 4K video to 1080p for OpenShot editing.
Official Guide(More details here): http://www.pavtube.com/4k-to-openshot.html
Pavtube Video Converter: http://www.pavtube.com/video_converter/
Pavtube Video Converter for Mac: http://www.pavtube.com/video-converter-mac/
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