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now:

I have a video .mp4 file, it's 792,4 Mb, made with KDEnlive

with this simple command line

ffmpeg -i original_file.mp4" shrinked_file.mp4

it goes down to 186,6 Mb 😵

#video

I watched them both and I don't perceive any difference !

How is this even possible ??
pick your poison:

`ffmpeg -codecs`

Whatever is default for your ffmpeg I guess :)
I have no idea whatsoever what all that stuff means !!
well, I found something

the viseo is h.264 in both files

BUT

the original bitrate is 3477
in the shrinked version, it's 742

Audio is mpeg-4 AAC for both

BUT

The original kbps is 241
the shrinked one os 128

But I swear I see no difference when I watch it !!
now do h.265/HEVC and VP9 :)
ehm...

would you paste me the command line ?

I can't figure it out myself

KDEnlive requires about 40 minutes to export in h.265/HEVC
Ah… yeah. It's computation power versus file size :)

Also kdenlive is probably running without gpu acceleration and not multithreaded but that's another can of worms.

ffmpeg -i INPUT -c:v libx265 -an -x265-params crf=25 OUT.mp4

crf is Constant Rate Factor (basically quality) from 0 (best quality) to 51 (lowest filesize)
jeez

the previous conversion run at 2.7 speed

this one is running at 0.31 speed !

This video thing is a black hole !! 🤐