I'm not sure about particular package you're talking about, but usually ffmpeg library and any PHP wrapper above it is used (at least php-ffmpeg), general command for CLI looks like this (you can take random time for your videos)
ffmpeg -i $uploaded_file -ss 00:00:01.000 -vframes 1 output.png
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I'm not sure about particular package you're talking about, but usually ffmpeg library and any PHP wrapper above it is used (at least php-ffmpeg), general command for CLI looks like this (you can take random time for your videos)
ffmpeg -i $uploaded_file -ss 00:00:01.000 -vframes 1 output.png