I took a video of myself for a wedding greeting with my phone (LG Nexus 5 [Android]) sitting (the phone that is) in a windshield suction holder. The video is 3'42" long and when downloaded to my PC from Google Photos it was 55 MB, more or less as expected.
I then wanted to edit out the beginning and end of the clip where I stand up from my chair to start at stop the video shooting. At first I downloaded Lightworks, cut out the beginning and end and exported the sequence (for YouTube 720. My only other option not having the pro version was for Vimeo). The new file being 5% shorter took up 181 MB.
OK, so clearly there is some format/compression thing going on that I'm trying to avoid going too deep into. Instead I found out I could just cut the beginning and on my phone hoping to preserve the native formatting/compression. The editing tools there were rather coarse but it did the job. It then took forever to save the edited video. The new shortened video (still 5% shrunken) takes up 905 MB of space.
My question is. Is there a simple (and free) way to simply cut down the length of a video clip while preserving the formatting and compression so that the file will just shrink in size proportionally to the shrinkage of duration?
Looking forward to you advice.