[FFmpeg-user] Low light settings.

[jiran.coline at laposte.net]

Hi, 

I try to encode 8-bits, 4K at 100 Mbps videos with HEVC. 
The result is really nice when there is enough light (even with default options), but as soon as the light decreases (or when there is too much dark elements in the scene), I can't get a nice output video : it has a lot of pixel stretching OR a very high bitrate (with the CRF option). 

I tried -tune grain or aq-mode=3, i tried to denoise my scene (it works a little bit), but honestly, the results are not really good. 

Can you help ? Thanks !