4k video exports 4x larger than original?


#1

Ahoy!
using geforce experience i recorded 11:32mins of 4k-60fps-130Mbps which takes up 10.2gb (an understandable size given my demand.) and once ive placed it into shotcut, added a 6 second into video and exported it all. my final file size for the 11:38min clip is now 46.7gb! the video quality is exactly the same as the original which is fine but that file size is ungodly!

my export settings are as followed:
H.264 Highprofile
res - 3840x2160 - 16:9 - 59.995fps
scan mode - progressive
field order - bottom first
deinterlacer - yadif, temporal, spatial (best)
interpolation - hyper/lanczos (best)
parallel processing - enabled

codec - libx264
rate control - quality based vbr
quality - 100%
gop - 13
b frames - 2

audio is left as default. no need to change it.

i would very much like to keep the best quality possible hence the ‘quality-100%’ however i couldnt find much about ‘gop’ or ‘b frames’ so that may need tweaking.

any help to reduce the size down would be very much appreciated thanks!


#2

Here’s your main problem.

Remember the original source video is ALREADY COMPRESSED.
If you unpack it while editing then repack it with essentially zero compression (100% Quality) then of course it will be much larger. You can’t ADD image quality by giving it less compression after the fact.