[SOLVED]Use ffplay to check how much to brighten video before using ffmpeg?

[yetanotherlogin]

Hello,

I have a video which is a bit dark that I'd like to re-encode and brighten up with ffmpeg.

As a smarter/faster alternative to running ffmpeg in trial/error mode, is there a way to simply use ffplay to find how much to brighten things up, before running ffmpeg with the same settings?

"ffplay -h" returns so much infos that it's hard for newbies

Thank you.

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Edit: This did the job:

ffmpeg -i input.mp4 -c:v libx264 -vf lutyuv=y=val*1.4,format=pix_fmts=yuv420p -c:a copy -f mp4 output.mp4

[evgraff]

Also interested in this question, tell us how to do it.